Risk of malignancy associated with diagnostic categories of the proposed World Health Organization International System for Reporting Pancreaticobiliary Cytopathology.

BACKGROUND: The World Health Organization (WHO) has proposed an updated international classification system for reporting pancreaticobiliary cytology. Substantial changes to the prior Papanicolaou Society of Cytopathology (PSC) system have been recommended. Chiefly, the "neoplastic: benign" and "neoplastic: other" categories have been replaced by 2 new categories-"pancreatic neoplasia-low-grade" (PaN-Low) and "pancreatic neoplasia-high-grade" (PaN-High)-stratifying neoplastic mucinous cysts by cytological atypia. Low-grade malignancies are placed in the "malignant" category and benign serous cystadenoma in the "benign/negative" category. Risk of malignancy (ROM) associated with the diagnostic categories of the WHO system has yet to be defined. METHODS: All patients who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for a pancreatic lesion at a single institution from January 2016 to December 2016, prospectively classified using the PSC system, were reclassified using the WHO system. Absolute ROM was determined by histologic outcome and/or clinical follow-up of at least 6 months. RESULTS: A total of 334 EUS-FNA samples from 322 patients were reviewed and reclassified. Absolute ROM for the WHO system was 7.7% for "insufficient/inadequate/nondiagnostic" category, 1.0% for "benign/negative for malignancy," 28.0% for "atypical," 4.8% for "PaN-Low," 60.0% for "PaN-High," 100% for "suspicious for malignancy," and 100% for "malignant;" the absolute ROM for the same cohort using the PSC system was 7.7% for "nondiagnostic" category, 1.0% for "negative (for malignancy)," 28.0% for "atypical," 0.0% for "neoplastic: benign," 30.3% for "neoplastic: other," 100% for "suspicious (for malignancy)," and 100% for "positive or malignant." CONCLUSIONS: The WHO international system achieves improved stratification by associated ROM compared to the PSC system.

Risk of malignancy in the categories of the Papanicolaou Society of Cytopathology system for reporting pancreaticobiliary cytology.

BACKGROUND: Management of pancreatic lesions depends on the risk of malignancy, which is primarily determined from the cytologic and radiologic evaluation findings. The Papanicolaou Society of Cytopathology (PSC) published a classification system for reporting pancreaticobiliary cytology. However, the "neoplastic: other" category can be further stratified by high-grade atypia (HGA). Studies on the risk of malignancy using the PSC system have been limited. MATERIALS AND METHODS: All patients who had undergone endoscopic ultrasound-guided fine-needle aspiration (FNA) for a pancreatic lesion at Massachusetts General Hospital from January 2016 to December 2016 were prospectively classified. The clinical, radiographic, and endoscopic findings, cytologic and histologic diagnoses, and follow-up data from 334 FNA biopsies from 322 patients were reviewed. The neoplastic: other category was subclassified as low-grade atypia or HGA. The absolute risk of malignancy was determined by the histologic outcome or follow-up of ≥6 months. RESULTS: The absolute risk of malignancy was 7.7% for the nondiagnostic category; 1.0% for negative; 28.0% for atypical; 0.0% for neoplastic: benign; 30.3% for neoplastic: other; 90.0% for neoplastic: other with HGA; 100% for suspicious; and 100% for positive. When the neoplastic: other with HGA, suspicious, and positive cytologic diagnoses were considered positive, the sensitivity, specificity, positive predictive value, and negative predictive value for pancreatic FNA biopsy was 92.2%, 98.8%, 98.3%, and 94.3%, respectively. CONCLUSIONS: Categories of the PSC system each carry an implied absolute risk of malignancy, increasing from the negative to positive categories. The presence of HGA identifies lesions at the greatest risk of malignancy in the neoplastic: other category, and its inclusion with suspicious and positive as positive diagnoses optimizes the diagnostic performance of identifying high-risk lesions that warrant surgical excision.

Risk of malignancy in pancreatic cysts with cytology of high-grade epithelial atypia.

BACKGROUND: The risk of malignancy is weighed against the attendant risks of surgery in the clinical management of pancreatic cysts. The latter are a group of histologically diverse and prognostically variable entities, and the risk of malignancy therein is primarily based on imaging characteristics-with or without high-grade atypia. Cytologic criteria for high-grade atypia in intraductal papillary mucinous neoplasms have recently been defined, and its recognition in all pancreatic cysts may help to guide management. METHODS: All patients who underwent endoscopic ultrasound-guided fine-needle aspiration for a pancreatic cyst at Massachusetts General Hospital from June 2015 to October 2016 were prospectively evaluated. Clinical data, radiographic impressions, biochemical analyses, and cytologic diagnoses of 118 pancreatic cyst fine-needle aspiration biopsy specimens from 106 patients were reviewed. Clinical and radiologic data were used as follow-up for 86 patients, and histology was obtained in 20 cases. Cysts were classified by imaging as high-risk, worrisome, or low-risk as defined by the 2012 Fukuoka consensus guidelines. Cytology was categorized as low-grade or high-grade. Malignant histology included mucinous cysts with high-grade dysplasia, invasive adenocarcinomas, and neuroendocrine tumors. The risk of malignancy (ROM) was determined by histological outcome. RESULTS: The presence of high-grade cytology (P < .01) was the only statistically significant predictor of malignancy and was 89% sensitive and 98% specific for malignancy. The positive predictive value (ie, ROM) of high-grade atypia on cytology was 80%. CONCLUSIONS: High-grade atypia is both sensitive and specific for identifying high-risk pancreatic cysts and is associated with a high risk of malignancy, and thus resection is warranted.

Moray micro forceps biopsy improves the diagnosis of specific pancreatic cysts.

BACKGROUND: Making a specific diagnosis of pancreatic cysts preoperatively is difficult. The new disposable Moray micro forceps biopsy (MFB) device allows tissue sampling from the pancreatic cyst wall/septum and aims to improve diagnosis. This study compares the diagnostic performance of the MFB with the current conventional analysis of pancreatic cyst fluid (PCF). METHODS: A total of 48 patients sampled with MFB were identified. Cysts were classified as mucinous on PCF based on extracellular mucin/mucinous epithelium, carcinoembryonic antigen (CEA) levels ≥192 ng/mL, or KRAS/GNAS mutation. A diagnosis of intraductal papillary mucinous neoplasm was supported by GNAS mutation; a diagnosis of serous cystadenoma was supported by Von Hippel-Lindau tumor suppressor (VHL) mutation. A diagnosis of mucinous cystic neoplasm required the presence of subepithelial ovarian-type stroma. A high-risk cyst was defined as a mucinous cyst with high-grade dysplasia or an adenocarcinoma. Comparisons in diagnostic performance between PCF and MFB were made. RESULTS: The mean age of the patients was 69.6 years (range, 27-90 years); 25 of 48 patients (52.1%) were female. Cysts were in the pancreatic head (13 patients), neck (2 patients), body (20 patients), and tail (13 patients), averaging 3.1 cm (range, 1.2-6.0 cm). There was concordance with mucinous versus nonmucinous classification (60.4% for PCF vs 58.3% for MFB; P = .949). Three high-risk cysts were detected by PCF and 2 were detected by MFB (P = .670). However, MFB diagnosed significantly more specific cysts compared with PCF (50.0% for MFB vs 18.8% for PCF; P<.001). CONCLUSIONS: PCF analysis and MFB have comparable performance in distinguishing between mucinous and nonmucinous cysts and for detecting high-risk cysts. However, MFB was found to be superior for diagnosing specific cyst subtypes, thus adding significant value to preoperative patient management. Cancer Cytopathol 2018;126:414-20. © 2018 American Cancer Society.

Automated Extraction of Formalin-Fixed, Paraffin-Embedded Tissue for High-Risk Human Papillomavirus Testing of Head and Neck Squamous Cell Carcinomas Using the Roche Cobas 4800 System.

CONTEXT: -Testing for high-risk human papillomavirus (HR-HPV) in head and neck squamous cell carcinomas (HNSCCs) is important for both prognostication and clinical management. Several testing platforms are available for HR-HPV; however, effective alternative automated approaches are needed. OBJECTIVE: -To assess the performance of the automated Roche cobas 4800 HPV real-time polymerase chain reaction-based system on formalin-fixed, paraffin-embedded HNSCC specimens and compare results with standard methods of in situ hybridization (ISH) and p16 immunohistochemistry. DESIGN: -Formalin-fixed, paraffin-embedded samples of HNSCC were collected from archival specimens in the Department of Pathology, Massachusetts General Hospital (Boston), and prepared using the automated system by deparaffinization and dehydration followed by tissue lysis. Samples were integrated into routine cervical cytology testing runs by cobas. Corresponding formalin-fixed, paraffin-embedded samples were evaluated for HR-HPV by ISH and p16 by immunohistochemistry. Discrepant cases were adjudicated by polymerase chain reaction. RESULTS: -Sixty-two HNSCC samples were analyzed using the automated cobas system, ISH, and immunohistochemistry. Fifty-two percent (n = 32 of 62) of formalin-fixed, paraffin-embedded tumors were positive for HR-HPV by cobas. Eighty-eight percent (n = 28 of 32) of cases were the HPV 16 subtype and 12% (n = 4 of 32) were other HR-HPV subtypes. Corresponding testing with ISH was concordant in 92% (n = 57 of 62) of cases. Compared with the adjudication polymerase chain reaction standard, there were 3 false-positive cases by cobas. CONCLUSIONS: -Concordance in HNSCC HR-HPV status between cobas and ISH was more than 90%. The cobas demonstrated a sensitivity of 100% and a specificity of 91% for detection of HR-HPV. Advantages favoring cobas include its automation, cost efficiency, objective results, and ease of performance.

Next-Generation Sequencing and Fluorescence in Situ Hybridization Have Comparable Performance Characteristics in the Analysis of Pancreaticobiliary Brushings for Malignancy.

Cytological evaluation of pancreatic or biliary duct brushings is a specific, but insensitive, test for malignancy. We compared adjunctive molecular testing with next-generation sequencing (NGS) relative to fluorescence in situ hybridization (FISH) for detection of high-risk neoplasia or malignancy. Bile duct brushings from 81 specimens were subjected to cytological analysis, FISH using the UroVysion probe set, and targeted NGS. Specimens were placed into negative/atypical (negative) or suspicious/positive (positive) categories depending on cytology and negative or positive categories on the basis of FISH and NGS results. Performance characteristics for each diagnostic modality were calculated on the basis of clinicopathologic follow-up and compared in a receiver operating characteristic analysis. There were 33 high-risk neoplasia/malignant strictures (41%) and 48 benign (59%). NGS revealed driver mutations in 24 cases (30%), including KRAS (21 of 24 cases), TP53 (14 of 24 cases), SMAD4 (6 of 24 cases), and CDKN2A (4 of 24 cases). Cytology had a sensitivity of 67% (95% CI, 48%-82%) and a specificity of 98% (95% CI, 89%-100%). When added to cytology, NGS increased the sensitivity to 85% (95% CI, 68%-95%), leading to a significant increase in the area under the curve in a receiver operating characteristic analysis (P = 0.03). FISH increased the sensitivity to 76% (95% CI, 58%-89%), without significantly increasing the area under the curve. These results suggest that ancillary NGS testing offers advantages over FISH, although studies with larger cohorts are needed to verify these findings.

Performance of the Roche cobas 4800 high-risk human papillomavirus test in cytologic preparations of squamous cell carcinoma of the head and neck.

BACKGROUND: Determining high-risk human papillomavirus (HR-HPV) status of head and neck squamous cell carcinoma (HNSCC) defines a tumor subset with important clinical implications. Cytologic sampling often provides the sentinel or sole diagnostic specimen. The authors assessed the performance characteristics for the Roche cobas 4800 HPV real-time polymerase chain reaction (PCR)-based system (cobas) on cytologic specimens of HNSCC compared with standard methods of in situ hybridization (ISH) for HR-HPV and immunohistochemistry (IHC) for p16 on formalin-fixed, paraffin-embedded (FFPE) tissue. METHODS: Samples of HNSCC were collected by fine-needle aspiration and from surgical biopsies or resections, fixed, and processed with the cobas system. Available corresponding FFPE samples were synchronously evaluated for HR-HPV using ISH and IHC. Discrepant cases underwent additional PCR studies for adjudication. RESULTS: Thirty-six samples from 33 patients were analyzed. Forty-two percent (n = 15) of tumors were positive for HR-HPV according to cobas. Corresponding histology with ISH (n = 30) was concordant in 91% of samples. Compared with the adjudication PCR standard, there were 3 false-positive cases according to cobas. Ninety-two percent (n = 12) of cases were the HPV16 subtype. The overall sensitivity for the cobas system was 100%, and the specificity was 86%. CONCLUSIONS: Concordance in HNSCC HR-HPV status between cobas and ISH/IHC was > 90%, and cobas demonstrated a sensitivity of 100% and a specificity of 86%, broadening options for HR-HPV testing of fine-needle aspiration samples. Advantages for this system include subtyping of HR-HPV and the ability to discern HR-HPV status earlier in a patient's treatment course.