The Bethesda System for Reporting Thyroid Cytopathology is largely based on data from adult studies. Although thyroid nodules in children are rare, the rate of malignancy is high. The authors' aim was to analyze the cytomorphology and mutational profiles in pediatric thyroid fine-needle aspirations (FNAs).

Thyroid FNAs from patients 21 years old or younger were identified from the authors' pathology archive, categorized using the Bethesda System for Reporting Thyroid Cytopathology, and correlated with histological and molecular follow-up.

A total of 179 samples from 142 patients were identified, including 96 cases (54%) with histological follow-up and 66 cases (37%) with molecular data. The diagnoses included 21 (12%) unsatisfactory, 82 (46%) negative, 43 (24%) atypia or follicular lesion of undetermined significance, 19 (11%) suspicious for follicular neoplasm, 6 (3%) suspicious for malignancy, and 8 (4%) positive for malignancy. The rate of malignancy in each category was 0%, 7%, 28%, 58%, 100%, and 100%, respectively. Of the 66 FNAs with molecular data, there were 11 (17%) positive for mutations. All mutation-positive FNAs were papillary thyroid carcinomas (PTCs) on resection. The overall sensitivity and specificity in this population were 80% and 100%, respectively.

This study demonstrates that thyroid FNA in children is a sensitive and highly specific tool. There was a 17% positivity rate for a genetic mutation, which correlated with malignancy in all cases. In comparison to adults, there was a higher prevalence of RET/PTC mutations and lower prevalence of BRAF mutations, which may in part explain the less aggressive nature of PTCs reported in children. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

To evaluate the efficacy and the limitation of fine-needle aspiration (FNA) biopsy in thyroid bed lesions, a retrospective review was performed of the medical records of thyroid cancer patients who underwent ultrasound-guided FNA biopsy of the thyroid bed at The University of Texas MD Anderson Cancer Center over a 5-year period.

Data were reviewed on 220 FNA biopsies taken from thyroid bed lesions in 195 patients who had undergone thyroidectomy for thyroid carcinoma. Thyroid bed FNA results were compared with clinical follow-up, including neck dissection results.

Recurrent carcinoma was diagnosed by FNA biopsy in 139 of 220 (63%) cases. Neck dissections were performed for 112 sites identified by FNA biopsies, and recurrent carcinoma was confirmed in 110 sites. The concordance between positive and/or suspicious FNA diagnosis and positive neck dissection results was 98% (118 of 120 cases). A false-positive FNA occurred in one patient with follicular thyroid carcinoma. The other discrepancy was attributed to failure to remove the lesion by neck dissection. The diagnostic accuracy of thyroid bed FNA was 100% in papillary and medullary thyroid carcinoma and 93% in follicular thyroid carcinoma. Suspicious and rare false-negative FNA results were attributed to low cellularity and lack of characteristic cytomorphologic features of thyroid carcinoma.

Ultrasound-guided thyroid bed FNA biopsy is accurate and efficient in triaging patients who require post-thyroidectomy follow-up for recurrent thyroid carcinoma. Caution should be taken in the interpretation of FNA specimens that have low cellularity and lack characteristic cytologic features of thyroid carcinoma. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Margin status is a predictor of outcome for patients with liver malignancies, although what constitutes a negative margin is controversial. Traditionally, the completeness of resection is estimated by surgical histopathology of the resected specimen margin, despite the in situ margin being potentially more important. The true margin is often altered by parenchymal transection techniques. The authors propose that cytologic assessment of the in situ margin is more specific for determining the true margin.

A total of 84 patients with primary or metastatic liver tumors who were undergoing surgical resection were enrolled in this prospective Institutional Review Board-approved study. Specimen and in situ (patient) margins were assessed using a “scrape preparation” cytologic technique and compared with traditional surgical histopathology. Patients were followed for assessment of local disease recurrence.

Follow-up data were complete for 64 patients for a median of 37 months (range, 12 months-56 months). Twenty patients were excluded because of perioperative death (6 patients; 7%) or a follow-up of < 12 months. Seven patients (12.2%) had positive histopathologic specimen margins, but only 1 was found to be positive by cytology (1.8%). No in situ cytologically positive margins were identified along the cut edge of the liver remnant. The rate of intra- or extrahepatic recurrences was 56.7%, whereas the local recurrence rate was 1.8%. One patient with local recurrence demonstrated simultaneous intra- and extrahepatic disease recurrences and had negative margins by all methods of evaluation.

To the authors' knowledge, the current study is the first to demonstrate that in situ margins can be assessed using cytopathology. This method is quick and can be universally applied. Given the difficulty of accurately assessing margins after hepatectomy, cytopathologic evaluation may be more reflective of the true margin. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Although thyroid fine-needle aspiration (TFNA) is an excellent test in evaluating thyroid nodules, there are occasionally false negatives (FN). The clinical impact and pathologic features of FN TFNA is understudied in the peer-reviewed literature.

A cohort of patients with thyroid cancer was separated into those with referring FN TFNA and those with referring true positive (TP) TFNA. Preoperative characteristics, pathologic finding, and clinical outcomes were compared within the 2 groups.

A total of 192 patients with TP TFNA (n = 162) and FN TFNA (n = 30) were included in the study. There were no significant differences in the demographics or length of follow-up of the 2 groups. The FN TFNA group was more likely to have a larger clinical nodule size and experienced a significant delay from initial TFNA to surgery. The FN TFNA group was more likely to be diagnosed with the follicular variant of papillary thyroid cancer (73.3% vs 25.9%, P < .001), less likely to have positive lymph nodes at surgery (6.7% vs 35.8%, P = .001), and more likely to undergo 2-step surgery (30% vs 9.9%, P = .007). Despite the delay in diagnosis, persistent/recurrent or metastatic disease, incidence of aggressive histologic variants, and pT4 disease was not different in the 2 groups.

The clinical impact of FN TFNA at our high-volume center is minimal. Cancers in this setting are low grade, and outcomes are not adversely affected despite the delay in diagnosis. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

The current study was conducted to describe the clinical features and presentation, cytomorphological characteristics with histological correlation, and prognosis of patients who undergo fine-needle aspiration (FNA) for postradiation sarcoma (PRS).

A retrospective review was performed of 13 individual patients who were pooled from the FNA services of 3 academic institutions between 2001 and 2012. Cases were reviewed for the primary tumor, radiation history, latency period, and other distinguishing clinical features. The frequency of the various cytological preparations as well as the use of immunohistochemistry (IHC) on this material were reviewed. The cytopathology diagnosis was compared with the resection diagnosis, and the survival time was reviewed.

The median age of the patients was 61 years (range, 35 years-94 years) and no significant gender predilection was noted. The median latency period was 11 years (range, 5 years to > 50 years). Patients generally presented with large tumors (median, 8 cm [range, 3 cm-12 cm]), and the median survival was 14 months (range, 6 months-46 months). Nine of 13 patients died of their disease and 1 was lost to follow-up. The tumors were morphologically heterogeneous. IHC played an important role in excluding other diagnoses in those cases in which sufficient material was available.

PRS is a morphologically heterogeneous entity that can be diagnosed by FNA. It is a diagnosis of exclusion that requires a history of therapeutic radiation and often requires IHC to rule out locally recurrent malignancy. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

This retrospective study compared the nondiagnostic rate for endoscopic ultrasound-guided (EUS) fine-needle aspiration (FNA) of pancreatic lesions in 2 settings: 1 with and 1 without on-site evaluation.

The authors reviewed 381 consecutive cases and divided them into groups with and without on-site adequacy evaluation. For the group with on-site evaluation, cytopathology personnel prepared and evaluated Diff-Quik–stained direct smears and rinsed the remaining material in CytoLyt solution (Cytyc Corporation, Marlborough, Mass). The group without on-site evaluation was divided into 2 subgroups: the clinical team either prepared an air-dried smear for each FNA pass and then rinsed the remaining material in CytoLyt, or the entire sample was rinsed in CytoLyt. The cytologic diagnoses were reviewed and the nondiagnostic rates for each group were calculated.

On-site evaluation was provided for 167 cases with a nondiagnostic rate of 25.8% (43 of 167 cases). On-site evaluation was not provided for 214 cases with a nondiagnostic rate of 24.3% (52 of 214 cases). The nondiagnostic rate for the subgroup with air-dried smears prepared by the clinical team was 25.6% (43 of 168 cases) and that for the subgroup with the entire sample rinsed in CytoLyt was 19.6% (9 of 46 cases). There were no significant statistical differences in nondiagnostic rates noted among the different groups or subgroups.

The results of the current study indicate that when experienced operators perform EUS FNA of pancreatic lesions, on-site adequacy evaluation offers no benefit in reducing the nondiagnostic rate. Optimizing visualization of the sampled material by omitting the preparation of direct smears and rinsing the entire sample in liquid-based media demonstrated a trend toward improving the diagnostic rate. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

The human immunoglobulin heavy-chain (IGH) locus at chromosome 14q32 is frequently involved in different translocations of non-Hodgkin lymphoma (NHL), and the detection of any breakage involving the IGH locus should identify a B-cell NHL. The split-signal IGH fluorescence in situ hybridization-chromogenic in situ hybridization (FISH-CISH) DNA probe is a mixture of 2 fluorochrome-labeled DNAs: a green one that binds the telomeric segment and a red one that binds the centromeric segment, both on the IGH breakpoint. In the current study, the authors tested the capability of the IGH FISH-CISH DNA probe to detect IGH translocations and diagnose B-cell lymphoproliferative processes on cytological samples.

Fifty cytological specimens from cases of lymphoproliferative processes were tested using the split-signal IGH FISH-CISH DNA probe and the results were compared with light-chain assessment by flow cytometry (FC), IGH status was tested by polymerase chain reaction (PCR), and clinicohistological data.

The signal score produced comparable results on FISH and CISH analysis and detected 29 positive, 15 negative, and 6 inadequate cases; there were 29 true-positive cases (66%), 9 true-negative cases (20%), 6 false-negative cases (14%), and no false-positive cases (0%). Comparing the sensitivity of the IGH FISH-CISH DNA split probe with FC and PCR, the highest sensitivity was obtained by FC, followed by FISH-CISH and PCR.

The split-signal IGH FISH-CISH DNA probe is effective in detecting any translocation involving the IGH locus. This probe can be used on different samples from different B-cell lymphoproliferative processes, although it is not useful for classifying specific entities. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Most malignancies identified by thyroid fine-needle aspiration (FNA) are papillary thyroid carcinoma (PTC). This study sought to determine if clinically adverse features of PTC correlate with the preceding cytologic diagnosis.

Thyroid FNA diagnoses were correlated with subsequent histopathologic findings.

From 6175 thyroid FNAs, histologic follow-up confirmed PTC in 52 of 184 (28%) FNAs with atypia of undetermined significance (AUS), 52 of 190 (27%) FNAs suspicious for follicular neoplasm, 182 of 229 (79%) FNAs that were suspicious for malignancy, and 188 of 198 (95%) FNAs that were malignant (M). Sex, age, and disease multifocality did not differ among FNA diagnosis groups. However, PTCs following an M FNA were more likely to have a higher American Joint Committee on Cancer T and N stage, and have lymphovascular invasion and/or extrathyroidal extension. Two patients had distant metastasis at initial surgery, whereas 16 developed subsequent recurrence and/or metastasis; all had a preceding M FNA. High-risk histologic subtypes of PTC also stratify to the M category, accounting at least partly for the association of cytologic diagnosis with adverse pathological parameters. Conversely, follicular variants of PTC predominate in non-M categories.

The Bethesda System for Reporting Thyroid Cytopathology conveys malignancy risk, but also predicts the presence of pathological risk factors and disease progression when the malignancy is PTC. M diagnoses identify higher risk PTCs, whereas AUS diagnoses identify low-risk PTCs, mostly follicular variants. These findings support the concept of conservative clinical management for some patients with AUS, while suggesting that a central neck dissection may be routinely justified in some patients with a M FNA. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Distinguishing hepatocellular carcinoma (HCC) from adenocarcinoma in fine-needle aspiration biopsies (FNAB) is often diagnostically challenging. Arginase-1 was recently described as a marker of hepatic differentiation in surgical resection specimens. We compared the expression of arginase-1, HepPar-1, and glypican-3 in FNAB of HCC and adenocarcinoma involving the liver.

Ninety-eight FNABs including 37 primary or metastatic HCCs (30 well or moderately differentiated and 7 poorly differentiated) and 61 adenocarcinomas involving the liver were evaluated for immunohistochemical expression of arginase-1, HepPar-1, and glypican-3 using formalin-fixed paraffin-embedded cell block material.

Arginase-1 was more sensitive (81%) than HepPar-1 (70%) or glypican-3 (54%) for HCC. Arginase-1 more often demonstrated diffuse staining, defined as reactivity in >50% of the tumor, in HCC (21 of 37; 57%) compared with HepPar-1 (15 of 37; 41%) and glypican-3 (12 of 37; 32%). Of the 7 poorly differentiated HCCs, 3 (43%) were immunoreactive for both arginase-1 and glypican-3, whereas only 1 (14%) demonstrated HepPar-1 staining. Arginase-1 expression was identified in adenocarcinomas of pancreatic, colorectal, and breast origin, and reactivity was diffuse in 2 pancreatic adenocarcinomas (2 of 15; 13%).

Arginase-1 is a more sensitive marker of hepatic differentiation than either HepPar-1 or glypican-3 in FNAB. In addition, arginase-1 exhibits more diffuse staining in HCC than either HepPar-1 or glypican-3, making interpretation easier in limited FNAB samples. Arginase-1 is not entirely specific for hepatic differentiation, as immunoreactivity can be identified in adenocarcinomas, particularly of pancreatic origin. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Antigen retrieval, a crucial technique for immunostaining, is often carried out on formalin-fixed, paraffin-embedded (FFPE) tissue sections. The role of antigen retrieval in immunostaining of ethanol-fixed smears remains unclear. The authors evaluated the effects of 2 common antigen retrieval procedures, heat-induced antigen retrieval and protease-induced antigen retrieval, for immunostaining using a broad panel of antibodies.

Papanicolaou-stained ethanol-fixed smears from 36 surgical specimens were immunostained with 43 antibodies. Three widely used heat-induced antigen retrieval solutions, namely, citrate buffer (pH 6.0 and pH 7.0) and ethylenediaminetetraacetic acid solution (pH 8.0) for heat-induced antigen retrieval, and pronase were used. The staining results were compared between the ethanol-fixed smears and the corresponding FFPE tissue sections.

Heat-induced antigen retrieval was essential for all the 9 antibodies examined against nuclear antigens, and for 7 of 26 antibodies against cytoplasmic and cell membrane antigens. Superior results were obtained using lower-pH heat-induced antigen retrieval solutions for ethanol-fixed smears than was the case for FFPE tissue sections; use of citrate buffer (pH 6.0) was optimal for most antibodies. For 17 antibodies against cytoplasmic/cell membrane antigens, satisfactory results were obtained even without antigen retrieval on the ethanol-fixed smears, whereas antigen retrieval was necessary for detection on the FFPE tissue sections. Protease-induced antigen retrieval frequently exerted deleterious effects on ethanol-fixed smears. Despite antigen retrieval, detection of 2 lymphocytic markers failed on ethanol-fixed smears. This limitation was overcome by heat-induced antigen retrieval on formalin vapor-fixed smears.

In ethanol-fixed smears, most of the antibodies can be immunostained successfully without antigen retrieval treatment or mild heat-induced antigen retrieval using citrate buffer (pH 6.0). The optimal antigen retrieval condition for each antibody must be individually determined. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Among sarcomas, a diagnosis of malignant peripheral nerve sheath tumor (MPNST) is often one of exclusion due to the absence of unequivocally characteristic histopathology, a conclusive immunohistochemical profile, or even a unique chromosomal anomaly. Because of this, the fine-needle aspiration (FNA) cytopathology of MPNST is extremely challenging. In the current study, the authors review their FNA experience with this neoplasm.

The authors searched their combined departmental cytology files for all lesions signed out as MPNST or suspicious for MPNST, as well as their own surgical pathology files for any cases of MPNST that had corresponding cytology. FNA was performed using standard techniques.

A total of 55 cases of MPNST, all with tissue confirmation, and 1 misdiagnosed example of melanoma were retrieved from 52 patients (M:F ratio of 1.5:1; average age, 46 years), 26 of whom had a history of neurofibromatosis type 1 (NF-1). Aspirates were from primary (27 cases), locally recurrent (14 cases), or metastatic (10 cases) MPNST; 4 primary tumor aspirates were of ex vivo specimens. Sites included the extremities (22 cases), trunk/pelvis (22 cases), head and neck (6 cases), and deep-seated masses (6 cases). FNA diagnoses were MPNST (24 patients); consistent with MPNST (5 patients); sarcoma, not otherwise specified (10 patients); atypical (3 patients); spindle cell neoplasm (6 patients); malignant neoplasm (1 patient); and nondiagnostic (3 patients). A definitive diagnosis of either MPNST or consistent with MPNST was issued in 30%, 93%, and 70%, respectively, of primary, locally recurrent, and metastatic lesions.

FNA cytopathology is limited as a diagnostic instrument for the initial diagnosis of MPNST, but is exceedingly accurate and valuable in the recognition of metastatic and locally recurrent MPNST. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

The sensitivity of urinary cytology for the diagnosis of urothelial carcinomas is low, particularly in low-grade carcinomas. The UroVysion test is a fluorescent in situ hybridization multiprobe assay that increases the sensitivity of urinary cytology. However, this test is not widely available. P16^INK4a, a protein involved in cell cycle progression, is overexpressed in urothelial carcinoma. Immunocytochemical expression of p16^INK4a has been examined in biopsy samples from urothelial carcinomas, but few studies have addressed this protein in urine cytology.

The authors compared the results of p16^INK4a immunoreactivity in cytology and biopsy samples from 83 cases, including low-grade urothelial carcinomas, reactive epithelial lesions, and negative cases.

p16^INK4a assessment of in urine cytology samples showed a sensitivity of 66.7% and a specificity of 82.8% in the diagnosis of low-grade urothelial carcinomas.

On the basis of these results, the authors propose that immunocytochemical detection of p16^INK4a is a reliable tool in urine cytology, both for the diagnosis of low-grade urothelial carcinomas and for follow-up purposes. More retrospective and prospective studies are required to verify these results. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), a rare subtype of Hodgkin lymphoma, is an indolent tumor with frequent instances of disease recurrence but a favorable prognosis. To the best of the authors' knowledge, there are only limited descriptions of NLPHL in the cytology literature because it was only formally recognized as a distinct entity in 1994.

In the current study, all cases of NLPHL diagnosed on excisional biopsy (n = 6 cases) at the study institution between 2000 and 2011 that had undergone previous fine-needle aspiration (FNA) were reviewed, with a focus on cytomorphologic features.

Four of 6 cases were termed benign on FNA; however, there was retrospective recognition of characteristic LP cells in all cases. Unlike classical Hodgkin lymphoma, the tumor cells of NLPHL were often found to be mononucleate and presented in a background of small lymphocytes. Other features identified included epithelioid histiocytes and numerous bare atypical nuclei.

Cases of NLPHL are commonly misdiagnosed as benign reactive lymphoid tissue and therefore a careful search using high magnification for LP cells is recommended in the evaluation of lymph node FNAs. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Fine-needle aspiration and bile duct brushing cytology have been traditionally used for early detection of pancreaticobiliary malignancy. Quite frequently, the cytological interpretations of these specimens are indeterminate. In this retrospective study, we evaluated the diagnostic value of detecting K-ras (v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) mutation in pancreaticobiliary cytology specimens that had equivocal cytological diagnoses.

A total of 129 cases that had indeterminate cytology diagnoses, K-ras mutational analysis, and histopathological follow-up were retrieved. The cytological interpretations, histopathological diagnoses, and K-ras mutation results were reviewed and analyzed.

Overall, the sensitivity and specificity of K-ras mutation for detection of pancreaticobiliary malignancy including adenocarcinoma, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm were 57% and 94%, respectively. The positive and negative predictive values of K-ras mutation for the presence of pancreaticobiliary malignancy were 94% and 60%, respectively.

The results demonstrate that K-ras mutation has a high predictive value for malignancy in patients with indeterminate pancreaticobiliary cytology and should be included as an important adjuvant diagnostic marker. It should be noted that a negative K-ras mutation result does not rule out malignancy, and K-ras mutation can be detected, although infrequently, in morphologically benign conditions. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Carbonic anhydrase IX (CAIX) is a hallmark of metabolic change in cancer cells. The aim was to evaluate the utility of CAIX expression for the detection of malignant pleural effusions by enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry.

A total of 97 pleural effusions including 54 benign effusions, 10 atypical effusions, and 33 malignant effusions, classified based on cytological diagnosis and etiology, were subjected to ELISA to measure protein level and to immunocytochemistry in cell blocks to determine CAIX expression.

CAIX levels were significantly higher in the malignant group compared with the benign group. Receiver operating characteristic curve analysis of benign and malignant pleural effusion for CAIX indicated an area under the curve of 0.82 with a value of 1882 pg/dL as the best threshold for distinguishing benign from malignant effusions, which yields a sensitivity, specificity, and accuracy of 63.6%, 94.4%, and 82.8%, respectively. None of the benign effusion expressed CAIX by immunocytochemistry. Malignant effusion cell blocks expressed CAIX in 63.6% of cases with 100% specificity. Upon combination of CAIX level and immunocytochemistry to detect malignant pleural effusions, the sensitivity and accuracy increased to 81.8% and 89.7%, respectively. The CAIX level determined by ELISA and the CAIX expression detected by immunocytochemistry were positively correlated. In atypical effusions, 5 cases (50%) exhibited CAIX levels higher than the cutoff value or were highlighted by CAIX immunocytochemistry.

ELISA and immunocytochemistry methods for determination of CAIX protein are potential additional tests for detection of malignant pleural effusions. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Fine-needle aspiration cytology (FNAC) is a well-accepted procedure for the diagnosis and biological characterization of breast carcinoma. Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status have a strong prognostic and predictive value in invasive breast carcinoma (IBC). ThinPrep (TP) cytology, which uses an alcohol-based fixative, is increasingly being used for immunocytochemistry. In this study, the authors compared the immunocytochemical evaluation of hormone receptors (HR) and HER2 on TP-processed FNAC with the immunohistochemical analysis performed on the corresponding formalin-fixed paraffin-embedded (FFPE) breast tumor specimens, which are considered the gold standard.

FNACs were performed on 116 primary IBCs at the time of diagnosis and subjected to immunocytochemical evaluation of HR and HER2 using the TP method. The same markers were immunohistochemical evaluated on the corresponding FFPE tissue specimens. HER2 fluorescent in situ hybridization analysis was performed only on the equivocal immunohistochemical results.

The HR results of the TP cytology specimens showed a very good agreement with those of the corresponding FFPE tissue samples (Cohen kappa test = 0.92; concordance rate = 98%) for estrogen receptor, and a good agreement (kappa = 0.76; concordance rate = 90.9%) for progesterone receptor. A perfect agreement (kappa = 1) was observed between TP and FFPE tissue samples in evaluating HER2 status.

Alcohol-based fixation seems not to affect the immunocytochemical evaluation of HR and HER2. Considering the high levels of agreement between the evaluation of HR and HER2, on both cytology specimens and on the corresponding FFPE tissue samples, the authors concluded that the TP technique can be routinely used for the biological characterization of IBC. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Arginase-I is a key urea cycle metalloenzyme that has been used as an immunohistochemistry (IHC) marker for hepatocellular carcinoma (HCC). Previous studies have demonstrated the efficacy of HepPar-1 and glypican-3 (GPC-3) IHC in liver fine needle aspiration (FNA) cytology.

Arginase-1 IHC was performed on FNA cell blocks, and its performance characteristics were compared with HepPar-1 and GPC-3. Ninety-two formalin-fixed, paraffin-embedded cell blocks were selected (HCC [n = 44], cirrhosis [n = 2], focal nodular hyperplasia [n = 3], hepatic adenomas [n = 2], dysplastic nodules [n = 6], and metastatic carcinomas [n = 35]). IHC staining with antibodies directed against arginase-1, HepPar-1, and GPC-3 was performed with appropriate positive and negative controls.

Arginase-1 positivity was demonstrated in 37 of 44 (84.1%) cases of HCC, compared with 32 of 44 cases (72.7%) and 25 of 44 cases (56.8%) for HepPar-1 and GPC-3, respectively. Arginase-1 and GPC-3 expression were not observed in any cases of metastatic carcinoma (0%), whereas HepPar-1 expression was present in 1 case of metastatic carcinoma. In addition, both arginase-1 and HepPar-1 expression were present in all 13 cases (100%) of nonmalignant hepatocellular lesions, whereas GPC-3 expression was absent in all 13 cases (0%).

This study demonstrates that both arginase-1 and HepPar-1 are effective IHC markers of hepatocellular differentiation. Furthermore, arginase-1 demonstrates superior sensitivity compared with GPC-3 and HepPar-1 in the diagnosis of HCC, whereas GPC-3 demonstrates superior specificity, as staining is not observed in benign hepatocellular lesions. Hence, use of arginase-1 with HepPar-1 and GPC-3 can aid in the diagnosis of HCC and separating from metastatic carcinoma. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Intrapancreatic accessory spleen (IPAS) is a rare benign lesion of the pancreas that frequently clinically and radiographically mimics a solid neoplasm. Very rarely, epidermoid cysts may form in IPAS and be mistaken for a cystic neoplasm of the pancreas on radiographic imaging. IPAS and epidermoid cyst involving intrapancreatic cyst (ECIPAS) are benign, and, if recognized, do not require surgical intervention. There are few reports of the cytopathologic features of IPAS diagnosed by fine needle aspiration (FNA).

Here we report a series of 6 cases of endoscopic ultrasound (EUS)-guided FNA of IPAS, 3 of which had histological confirmation, including 1 case of histologically confirmed ECIPAS.

Cytomorphologic features of IPAS include a polymorphous population of hematopoietic cells, including lymphocytes, eosinophils, histiocytes, plasma cells, and red blood cells, admixed with numerous small blood vessels representing splenic sinusoids. CD8 immunostaining of cell block or core biopsy material highlights splenic endothelial cells and confirms the diagnosis. FNA of ECIPAS reveals predominantly macrophages and proteinaceous debris.

Diagnostic pitfalls include pancreatic neuroendocrine tumor. If IPAS is recognized as a diagnostic consideration on EUS-FNA, unnecessary surgical resection may be avoided. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Novel high-throughput molecular technologies have made the collection and storage of cells and small tissue specimens a critical issue. The FTA card provides an alternative to cryopreservation for biobanking fresh unfixed cells. The current study compared the quality and integrity of the DNA obtained from 2 types of FTA cards (Classic and Elute) using 2 different extraction protocols (“Classic” and “Elute”) and assessed the feasibility of performing multiplex mutational screening using fine-needle aspiration (FNA) biopsy samples.

Residual material from 42 FNA biopsies was collected in the cards (21 Classic and 21 Elute cards). DNA was extracted using the Classic protocol for Classic cards and both protocols for Elute cards. Polymerase chain reaction for p53 (1.5 kilobase) and CARD11 (500 base pair) was performed to assess DNA integrity.

Successful p53 amplification was achieved in 95.2% of the samples from the Classic cards and in 80.9% of the samples from the Elute cards using the Classic protocol and 28.5% using the Elute protocol (P = .001). All samples (both cards) could be amplified for CARD11. There was no significant difference in the DNA concentration or 260/280 purity ratio when the 2 types of cards were compared. Five samples were also successfully analyzed by multiplex MassARRAY spectrometry, with a mutation in KRAS found in 1 case.

High molecular weight DNA was extracted from the cards in sufficient amounts and quality to perform high-throughput multiplex mutation assays. The results of the current study also suggest that FTA Classic cards preserve better DNA integrity for molecular applications compared with the FTA Elute cards. Cancer (Cancer Cytopathol) 2012. © 2012 American Cancer Society.

Cell block (CB) preparation during the endobronchial ultrasound-guided transbronchial fine-needle aspiration (EBUS-TBNA) procedure plays an important role in the diagnosis of lung cancer and recovery of cellular material for molecular characterization of the tumor. However, the efficiency of the conventional method of CB preparation is suboptimal.

In the current study, the “tissue coagulum clot” cell block (TCC-CB) method was used to prepare the CBs and its efficiency was compared with that of the conventional saline rinse cell block (NR-CB) method. A total of 84 consecutive TCC-CBs (106 lymph nodes [LNs] and 14 lung lesions) and 28 consecutive cases of NR-CB (39 LNs and 3 lung lesions) obtained within the same time period were included in the current study.

In the TCC-CB specimens, 94 of 106 LN cases (88.7%) yielded sufficient diagnostic material, as did 11 of 14 lung lesions (78.6%). In the NR-CB group, which was used as the control, 22 of 39 LN specimens (56.4%) and none of 3 lung specimens (0%) were found to provide sufficient diagnostic material. Although the average size of the LNs in the study group were not significantly different from those in the control group (1.76 cm vs 1.82 cm; P > .05), the overall nondiagnostic rates in the TCC-CB and NR-CB groups were 11.2% and 43.6%, respectively (P < .001). The nondiagnostic rates of the lung specimens were 15.4% in the TCC-CB group and 100% in the NR-CB group (P < .05). In addition, immunohistochemistry studies and epidermal growth factor receptor (EGFR)/KRAS mutational analyses were performed in 26 and 14 TCC-CB cases, respectively. With the exception of 1 case, all of them had satisfactory results.

The data from the current study demonstrate that the TCC-CB method significantly increases the cellular yield of CB preparations without compromising cytomorphological characterization of tumor cells. Cancer (Cancer Cytopathol) 2011;. © 2011 American Cancer Society.

Practice patterns regarding on-site assessment of the adequacy of image-guided fine needle aspiration biopsies (FNABs) vary among laboratories, but in many laboratories primary responsibility rests with the cytotechnologists. On-site evaluation provides feedback on the need for additional passes and facilitates triaging of the specimen for time-sensitive ancillary studies. Prior studies have suggested that cytotechnologists can assess the initially obtained specimens correctly, but they are few in number and limited by small size. The purpose of this study was to assess the frequency with which our cytotechnologists were able to correctly assess specimens as adequate using a large-scale database that included a wide range of image-guided FNABs.

The frequency that on-site adequacy assessments of 5241 image-guided FNABs were correct was determined by correlating the cytotechnologists' assessments of adequacy with the final cytologic interpretation. An adequacy assessment was considered correct if the FNAB was ultimately reported as satisfactory and unequivocally benign or malignant. An adequate reading on a case that was ultimately reported as unsatisfactory, atypical, or suspicious was deemed “incorrect.” The effect of imaging modality was also analyzed.

Of 5241 FNABs, 2784 (53%) were interpreted as adequate on site. Of these, 2637 (95%) were correctly considered adequate. Of the common biopsy sites sampled, the adequacy assessments for liver FNABs demonstrated the highest frequency for being correctly considered adequate (97%) and those for kidney FNABs showed the lowest (90%). Imaging modality had no effect on accuracy.

Cytotechnologists are almost always correct when assessing initial FNAB samples as adequate. Cancer (Cancer Cytopathol) 2011. © 2011 American Cancer Society.

The Bethesda System (TBS) for reporting thyroid cytopathology introduced the atypia of undetermined significance/follicular lesion of undetermined significance (AUS) category, but did not provide adequate guidance for the appropriate use of this diagnosis. In the current study, the authors sought to identify an appropriate measure for AUS use based on experience to date with TBS.

The authors reviewed 8 series, including their own laboratory experiences, with a total of 30,466 thyroid aspirates classified within TBS.

The median AUS rate was 9.9% with a range of 3.0% to 18.0%. Use of the individual diagnostic categories within TBS varied up to 12.7-fold. The ratio of “suspicious for follicular neoplasm” plus “suspicious for malignancy” to “malignant” (M) diagnoses varied the least (1.8-fold). The AUS:M ratio provided a suitable measure of assessing AUS use, with a median ratio of 2.0 and a range of 0.5 to 4.9.

Based on available studies, an AUS:M ratio of 1.0 to 3.0 is recommended. AUS:M ratios > 3.0 are likely because of overdiagnosis of AUS or underdiagnosis of M. AUS:M ratios < 1.0 are mostly due to low AUS rates, at the likely expense of sensitivity. Cancer (Cancer Cytopathol) 2012;. © 2011 American Cancer Society.

At present, thyroid fine-needle aspiration (FNA) specimens are diagnosed using a tiered classification scheme, with the most popular of these being the 5-tiered and 6-tiered systems. In this study, the authors present their institutional experiences using these 2 different systems and evaluate their efficacy based on the surgical follow-up.

Thyroid FNA specimens and their corresponding surgical resection specimens were collected between 2007 and 2009. The following diagnostic categories are used in both systems: unsatisfactory/nondiagnostic, benign, follicular neoplasm/suspicious for follicular neoplasm, suspicious for malignancy, and malignant. An additional category termed atypia of undetermined significance/follicular lesion of undetermined significance was used for atypical cases in the 6-tiered system. Statistical analysis was performed by comparing the different diagnostic categories.

The case cohort included a total of 7686 thyroid FNA specimens representing 3962 nodules and 3724 nodules, respectively, in the 5-tiered and 6-tiered systems. Negative predictive values for the benign categories (96.9% vs 97.5%; P = 1) and positive predictive values for both the follicular neoplasm categories (26.5% vs 32.1%; P = .2531) and the malignant categories (99.1% vs 99.4%; P = 1) were similar. The most significant differences between the 5-tiered and 6-tiered systems were the percentage of cases classified as benign (83.9% vs 55.4%; P < .0001) and as follicular neoplasms (4.6% vs 23.8%; P < .0001). It is interesting to note that fewer patients were referred for surgery in the 5-tiered system compared with the 6-tiered one (9.1% vs 36.5%; P < .0001).

Use of either the 5-tiered or 6-tiered reporting systems for thyroid FNA specimens can potentially affect the clinical management of patients with thyroid nodules. Cancer (Cancer Cytopathol) 2012. © 2011 American Cancer Society.

Recently, the Food and Drug Administration approved the use of the location-guided imaging system FocalPoint GS (FPGS), on SurePath Papanicolaou (Pap) tests for primary screening. The objective of the current study was to evaluate the impact of FPGS on the following: distribution of diagnostic categories; rate of high-risk human papillomavirus (HR-HPV)–positive ASC-US cases; and quality control (QC) data before and after FPGS implementation.

A search of the laboratory information system was performed to identify all SurePath Pap tests processed in our laboratory for the first 19 months after FPGS implementation. We also retrieved all SurePath specimens from a 16-month period prior to FPGS implementation to serve as the control. During the period from Janaury 2008 to April 2009, the FocalPoint Slide Profiler was used.

Implementation of FPGS resulted in a significantly higher percentage of LSIL and ASC-US interpretations, as well as a significant increase in the detection of candidiasis and bacterial vaginosis. The ASC-to-SIL ratio was 1.4 and 1.9 before and after FPGS implementation, respectively. There was a decrease in the HR-HPV positive rate in ASC-US cases, and a decrease in the estimated false-negative fraction after FPGS implementation.

In conclusion, our study seems to demonstrate a favorable performance of FPGS in the routine clinical setting. FPGS may have the potential to be a promising screening tool for gynecologic cytology in a low-risk patient population. Cancer (Cancer Cytopathol) 2012;. © 2011 American Cancer Society.

To the authors' knowledge, the diagnostic value of cell block (CB) as an adjunct to ThinPrep liquid-based cytology (LBC) of bronchial washing specimens in the detection and subclassification of pulmonary neoplasms has not been well evaluated. The objective of the current study was to evaluate the diagnostic utility of CB in this setting.

A total of 74 bronchial washing specimens and concurrently prepared CBs with a diagnosis of malignant or suspicious/atypical obtained from bronchoscopy procedures performed during 2009 were reviewed along with 28 randomly selected negative cases. LBC and CBs were reviewed independently. Deeper levels and ancillary studies were performed on CBs for specific tumor classification if needed. LBC and CB diagnoses were correlated with final histology and/or bronchial brushings.

Use of CBs increased the number of positive diagnoses from 18 (LBC only) to 30 (combined LBC and CB) and 36 (combined LBC and CB with ancillary studies), with increased diagnostic yields of 67% and 100%, respectively. CB without ancillary techniques detected 22 malignancies whereas LBC detected 18 malignancies and CB with ancillary techniques detected 29 malignancies. A specific tumor diagnosis was possible in 22 of 29 (76%) malignancies detected by CB. Bronchial brushings and histology confirmed malignancy in 91% and 92% of cases, respectively.

CB combined with LBC was found to improve the rate of detection of malignancy over LBC alone, especially in cases with suspicious or atypical LBC diagnoses. Increased diagnostic yield is observed when CB is used with or without ancillary studies, but the yield is higher with CB using ancillary studies. CB serves as yet another available source of diagnostic material for immunohistochemical and molecular studies. Cancer (Cancer Cytopathol) 2012;. © 2011 American Cancer Society.