Revisiting the performance of cyst fluid carcinoembryonic antigen as a diagnostic marker for pancreatic mucinous cysts: a comprehensive 20-year institutional review

OBJECTIVE

Elevated pancreatic cyst fluid carcinoembryonic antigen (CEA) has been routinely used to classify mucinous cysts. This study incorporates original data that established the CEA ≥192 ng/mL threshold with over 20 years of additional data and reassesses the diagnostic performance of CEA for differentiating mucinous from non-mucinous cysts.

DESIGN

1169 pancreatic cysts (1999-2021) with CEA results were identified. 394 cases had histological confirmation as the diagnostic standard. Additionally, 237 cysts without histological confirmation demonstrated KRAS, GNAS, or RNF43 mutations by molecular testing and were combined with the histologically confirmed cysts for separate analysis on a total cohort of 631 cysts.

RESULTS

Median CEA was significantly higher in mucinous cysts (323.9 ng/mL, n=314) versus non-mucinous cysts (204.6 ng/mL, n=80) (p<0.001). Receiver operating characteristic curve analysis demonstrated an optimal CEA cut-off of 20 ng/mL (area under the curve: 80%), though the specificity was lower than desired (sensitivity 89%, specificity 64%). At the previously established threshold of 192 ng/mL, sensitivity and specificity were 56% and 78%, respectively. To achieve a specificity of 85% as originally reported, a CEA threshold of 250 ng/mL was needed; the 13 false positive cases at this threshold included 4 benign simple cysts, 2 squamoid cysts, 1 serous cystadenoma, 1 lymphoepithelial cyst and 5 more uncommon entities. All results remained similar within the total cohort after including additional cases with KRAS/GNAS/RNF43 mutations only.

CONCLUSION

Cyst fluid CEA continues to be a useful test in the diagnosis of mucinous pancreatic cysts but does not appear as specific as previously reported. Raising the CEA threshold to 250 ng/mL to maintain specificity for differentiating mucinous from non-mucinous cysts may be considered.

COVID-19 pandemic impact on cytopathology practice in the post-lockdown period: An international, multicenter study

BACKGROUND

In a previous worldwide survey, the authors showed a drastic reduction in the number of cytological specimens processed during the coronavirus disease 2019 "lockdown" period along with an increase in malignancy rates. To assess the continued impact of the pandemic on cytological practices around the world, they undertook a second follow-up worldwide survey collecting data from the post-lockdown period (2020).

METHODS

Participants were asked to provide data regarding their cytopathology activity during the first 12 weeks of their respective national post-lockdown period (2020), which ranged from April 4 to October 31. Differences between the post-lockdown period and the corresponding 2019 period were evaluated, and the authors specifically focused on rates of malignant diagnoses.

RESULTS

A total of 29 respondents from 17 countries worldwide joined the survey. Overall, a lower number of cytological specimens (n = 236,352) were processed in comparison with the same period in 2019 (n = 321,466) for a relative reduction of 26.5%. The overall malignancy rate showed a statistically significant increase (12,442 [5.26%] vs 12,882 [4.01%]; P < .001) during the same time period. Similar results were obtained if both malignancy and suspicious for malignancy rates were considered together (15,759 [6.58%] vs 16,011 [4.98%]; P < .001).

CONCLUSIONS

The data showed a persistent reduction in the cytological specimen volume during the post-lockdown period (2020). However, the relative increase in the cytological workload in the late part of the post-lockdown is a promising finding of a slow return to normality.

Next-generation sequencing in the evaluation of biliary strictures in patients with primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis (PSC) is a well-described risk factor for the development of cholangiocarcinoma (CCA). Early detection of CCA in these patients is of great importance because it expands options for therapeutic interventions, including liver transplantation. Current diagnostic tests for the evaluation of biliary strictures are limited to biliary brushing (BB) cytology and fluorescence in situ hybridization (FISH). Next-generation sequencing (NGS) has become an important diagnostic tool in oncology and may be a useful tool for diagnosing CCA on BBs. It is not clear how NGS performs when it is added to BB cytology and FISH in patients with PSC.

METHODS

This study reports the authors' experience with NGS performed as a prospective cotest with cytology and FISH on BBs obtained from 60 patients with PSC followed at Massachusetts General Hospital. A duct with malignancy was defined as a high-risk (HR) stricture with either high-grade dysplasia or CCA.

RESULTS

NGS was better than FISH and cytology in detecting HR strictures, which showed multiple genetic mutations in all cases. NGS provided specific mutational information, and NGS results were reproducible in longitudinal samples.

CONCLUSIONS

Adding NGS to BB cytology and FISH in the evaluation of biliary strictures for patients with PSC may provide additional information that could help to inform clinical management.

Global impact of the COVID-19 pandemic on cytopathology practice: Results from an international survey of laboratories in 23 countries

BACKGROUND

To the authors' knowledge, the impact of the coronavirus disease 2019 (COVID-19) pandemic on cytopathology practices worldwide has not been investigated formally. In the current study, data from 41 respondents from 23 countries were reported.

METHODS

Data regarding the activity of each cytopathology laboratory during 4 weeks of COVID-19 lockdown were collected and compared with those obtained during the corresponding period in 2019. The overall number and percentage of exfoliative and fine-needle aspiration cytology samples from each anatomic site were recorded. Differences in the malignancy and suspicious rates between the 2 periods were analyzed using a meta-analytical approach.

RESULTS

Overall, the sample volume was lower compared with 2019 (104,319 samples vs 190,225 samples), with an average volume reduction of 45.3% (range, 0.1%-98.0%). The percentage of samples from the cervicovaginal tract, thyroid, and anorectal region was significantly reduced (P < .05). Conversely, the percentage of samples from the urinary tract, serous cavities, breast, lymph nodes, respiratory tract, salivary glands, central nervous system, gastrointestinal tract, pancreas, liver, and biliary tract increased (P < .05). An overall increase of 5.56% (95% CI, 3.77%-7.35%) in the malignancy rate in nongynecological samples during the COVID-19 pandemic was observed. When the suspicious category was included, the overall increase was 6.95% (95% CI, 4.63%-9.27%).

CONCLUSIONS

The COVID-19 pandemic resulted in a drastic reduction in the total number of cytology specimens regardless of anatomic site or specimen type. The rate of malignancy increased, reflecting the prioritization of patients with cancer who were considered to be at high risk. Prospective monitoring of the effect of delays in access to health services during the lockdown period is warranted.

Cytology Specimen Management, Triage and Standardized Reporting of Fine Needle Aspiration Biopsies of the Pancreas

The recent advances in pancreas cytology specimen sampling methods have enabled a specific cytologic diagnosis in most cases. Proper triage and processing of the cytologic specimen is pivotal in making a diagnosis due to the need for ancillary testing in addition to cytological evaluation, which is especially true in the diagnosis of pancreatic cysts. Newly proposed terminology for pancreaticobiliary cytology offers a standardized language for reporting that aims to improve communication among patient caregivers and provide for increased flexibility in patient management. This review focuses on these updates in pancreas cytology for the optimal evaluation of solid and cystic lesions of the pancreas.

Clinical evaluation, imaging studies, indications for cytologic study and preprocedural requirements for duct brushing studies and pancreatic fine-needle aspiration: The Papanicolaou Society of Cytopathology Guidelines

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreaticobiliary cytology including indications for endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) biopsy, techniques for EUS-FNA, terminology and nomenclature to be used for pancreaticobiliary disease, ancillary testing and postbiopsy management. All documents are based on expertise of the authors, literature review, discussions of the draft document at national and international meetings and synthesis of online comments of the draft document. This document selectively presents the results of these discussions. This document summarizes recommendations for the clinical and imaging work-up of pancreatic and biliary tract lesions along with indications for cytologic study of these lesions. Prebrushing and FNA requirements are also discussed.

Post-brushing and fine-needle aspiration biopsy follow-up and treatment options for patients with pancreatobiliary lesions: The Papanicolaou Society of Cytopathology Guidelines

The Papanicolaou Society of Cytopathology (PSC) has developed a set of guidelines for pancreatobiliary cytology including indications for endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) biopsy, techniques of EUS-FNA, terminology and nomenclature for pancreatobiliary cytology, ancillary testing and post-procedure management. All documents are based on the expertise of the authors, a review of the literature and discussions of the draft document at several national and international meetings over an 18 month period and synthesis of online comments of the draft document on the PSC web site (www.papsociety.org). This document selectively presents the results of these discussions and focuses on the follow-up and treatment options for patients after procedures performed for obtaining cytology samples for the evaluation of biliary strictures and solid and cystic masses in the pancreas. These recommendations follow the six-tiered terminology and nomenclature scheme proposed by committee III.

Clinical evaluation, imaging studies, indications for cytologic study, and preprocedural requirements for duct brushing studies and pancreatic FNA: the Papanicolaou Society of Cytopathology recommendations for pancreatic and biliary cytology

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreaticobiliary cytology including indications for endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) biopsy, techniques for EUS-FNA, terminology and nomenclature to be used for pancreaticobiliary disease, ancillary testing, and post-biopsy management. All documents are based on expertise of the authors, literature review, discussions of the draft document at national and international meetings, and synthesis of online comments of the draft document. This document selectively presents the results of these discussions. This document summarizes recommendations for the clinical and imaging work-up of pancreatic and biliary tract lesions along with indications for cytologic study of these lesions. Prebrushing and FNA requirements are also discussed.

Cystic pancreatic neuroendocrine tumors: endoscopic ultrasound and fine-needle aspiration characteristics

BACKGROUND AND STUDY AIMS

Limited data are available on the endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) characteristics of cystic pancreatic neuroendocrine tumors (CPanNets). The aims of this study were to describe the EUS and FNA characteristics of pathologically confirmed CPanNets and to compare these characteristics with mucinous cysts from matched patients.

PATIENTS AND METHODS

From an EUS - FNA database (between 1999 and 2011), 19 patients with a pathologically confirmed CPanNet were identified. Patient characteristics, cyst fluid carcinoembryonic antigen (CEA) levels, pathology, and EUS findings were analyzed. For comparison, age- and sex-matched patients with mucinous cysts were randomly chosen from the same database.

RESULTS

Of the 19 patients, two had multiple endocrine neoplasia type 1 and two had metastases. The median diameter of the lesions was 24 mm. EUS revealed unilocular lesions in 7 patients, thinly septated lesions with thin walls in 1, and mixed solid-cystic lesions in 11. EUS - FNA cytology confirmed neoplasm in 12 of the 19 patients (63.2 %). The median cyst fluid CEA level (n = 15) was 1.1 ng/mL (range 0.3 - 500 ng/mL). Compared with matched patients with mucinous cysts, the median cyst fluid CEA was lower (1.1 ng/mL vs. 400 ng/mL), thick walls were more common (66.7 % vs. 13.3 %), and diagnostic cytology was more likely (73.3 % vs. 20.0 %).

CONCLUSIONS

Analysis of EUS and FNA results showed that the cyst fluid from CPanNets had a lower CEA concentration, a higher frequency of thick walls on EUS, and higher diagnostic cytology compared with mucinous cysts. These findings may aid in the diagnosis of CPanNets.

International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas

The international consensus guidelines for management of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm of the pancreas established in 2006 have increased awareness and improved the management of these entities. During the subsequent 5 years, a considerable amount of information has been added to the literature. Based on a consensus symposium held during the 14th meeting of the International Association of Pancreatology in Fukuoka, Japan, in 2010, the working group has generated new guidelines. Since the levels of evidence for all items addressed in these guidelines are low, being 4 or 5, we still have to designate them "consensus", rather than "evidence-based", guidelines. To simplify the entire guidelines, we have adopted a statement format that differs from the 2006 guidelines, although the headings are similar to the previous guidelines, i.e., classification, investigation, indications for and methods of resection and other treatments, histological aspects, and methods of follow-up. The present guidelines include recent information and recommendations based on our current understanding, and highlight issues that remain controversial and areas where further research is required.

Lymphangioma of the pancreas: a multimodal approach to pre-operative diagnosis

BACKGROUND

Lymphangioma of the pancreas is an extremely rare benign tumour of lymphatic origin, with only four cases diagnosed by EUS-FNA reported to date.

METHODS AND MATERIALS

Five cases of either cytologically or histologically diagnosed pancreatic lymphangioma with pre-operative cytological analysis by EUS-FNAC were reviewed.

RESULTS

All patients were female, with a mean age of 56.4 years. By imaging, the cystic lesions ranged in size from 2 to 7 cm (mean 4.5 cm) and were mainly located in the head of the pancreas. All cysts had thin walls and no cyst demonstrated a mural nodule. Diagnosis based on imaging features was benign in all cases due to the absence of high-risk features. Four samples were sent for biochemical analysis, which showed low CEA levels (range, <0.5-19.4 ng/ml; mean, 5.45 ng/ml) and CA 19.9 and CA 72.4 levels within normal range. All cyst fluids showed numerous small lymphocytes with no atypia; no epithelial cells were present, including no gastrointestinal contamination. Flow cytometry in two cases showed T lymphocytes with a mature phenotype. Surgical resection in two patients confirmed the cytological diagnosis. Benign clinical follow-up was available in three patients at 2, 3 and 3.5 years.

CONCLUSION

A multimodal approach to cytological diagnosis (combining clinical, radiological and cyst fluid gross, biochemical and cytological characteristics) can lead to the diagnosis of this cystic neoplasm and distinguish it from other more common cysts in the pancreas, potentially avoiding the need for unnecessary surgery.

High-grade atypical epithelial cells in pancreatic mucinous cysts are a more accurate predictor of malignancy than "positive" cytology

BACKGROUND

The Sendai guidelines for risk assessment of malignancy in patients with mucinous cysts lists "positive" cytology as a high-risk feature. In the current study, the authors hypothesized that a cytological threshold of high-grade atypical epithelial cells (AEC) is a more accurate predictor of malignancy.

METHODS

The clinical, radiological, and cytological data of 112 patients with histologically confirmed mucinous cysts of the pancreas were reviewed. Cytology slides were blindly reviewed and cells were classified as benign, AEC, or malignant. On histology, neoplasms were grouped as benign (low-grade and moderate dysplasia) and malignant (high-grade dysplasia/carcinoma in situ and invasive carcinoma).

RESULTS

There were 92 patients with an intraductal papillary mucinous neoplasm (IPMN) and 20 with a mucinous cystic neoplasm; 39 were malignant and 73 were benign (42 with low-grade dysplasia and 31 with moderate dysplasia). Only 28% (11 of 39) of the malignant cysts were cytologically malignant with a sensitivity of 29%, a specificity of 100%, and an accuracy of 75%. AEC detected 17 additional cancers (44% of all malignant cysts; 16% more than detected on the basis of "positive" cytology). By using AEC as a surgical triage threshold, the sensitivity was 72%, the specificity was 85%, and the accuracy was 80%, with similar values for small (≤ 3 cm) branch duct IPMN. Nine of 73 (12%) benign cysts were identified with AEC, 4 of which had moderate dysplasia. AEC had a positive predictive value of 87% for the detection of a mucinous cyst with moderate dysplasia or worse.

CONCLUSIONS

AEC are a more accurate predictor of malignancy than "positive" cytology in aspirates of pancreatic mucinous cysts, including small branch duct IPMN. AEC warrant a "suspicious" interpretation for appropriate surgical triage.

Survey of medical training in cytopathology carried out by the journal Cytopathology

This report of the Editorial Advisory Board of Cytopathology gives the results of a survey of medical practitioners in cytopathology, which aimed to find out their views on the current situation in undergraduate and postgraduate training in their institutions and countries. The results show that training in cytopathology and histopathology are largely carried out at postgraduate level and tend to be organized nationally rather than locally. Histopathology was regarded as essential for training in cytopathology by 89.5% of respondents and was mandatory according to 83.1%. Mandatory cytopathology sections of histopathology were reported by 67.3% and specific examinations in cytopathology by 55.4%. The main deficiencies in training were due to its variability; there were insufficient numbers of pathologists interested in cytology and a consequent lack of training to a high level of competence. Pathologists without specific training in cytopathology signed out cytology reports according to 54.7% of responses, more often in centres where training was 3-6 months or less duration. Although 92.2% of respondents thought that specialist cytology should not be reported by pathologists without experience in general cytopathology, that practice was reported by 30.9%, more often in centres with small workloads. The survey report recommends that 6-12 months should be dedicated to cytopathology during histopathology training, with optional additional training for those wanting to carry out independent practice in cytopathology. Formal accreditation should be mandatory for independent practice in cytopathology. When necessary, temporary placements to centres of good practice should be available for trainees intending to practise independently in cytopathology. There should be adequate numbers of pathologists trained in cytopathology to a high level of competence; some of their time could be released by training cytotechnologists and trainee pathologists to prescreen cytology slides and assess adequacy of fine-needle aspiration samples when immediate diagnosis was not required. The survey demonstrated a clear need for European and international guidelines for training in cytopathology.

Diagnosis of pancreatic neoplasia with EUS and FNA: a report of accuracy

BACKGROUND

EUS-guided FNA has the potential to provide diagnostic cytologic material from pancreatic lesions that are suspicious for malignancy.

OBJECTIVE

To determine the operating characteristics of EUS-FNA in the diagnosis of pancreatic adenocarcinoma and pancreatic neuroendocrine neoplasms (PENs).

DESIGN

Retrospective analysis of a prospectively maintained database.

SETTING

Academic tertiary-care center.

PATIENTS

This study involved 559 patients undergoing evaluation of pancreatic masses or diffuse pancreatic parenchymal abnormalities.

MAIN OUTCOME MEASUREMENTS

Performance characteristics of EUS-FNA of pancreatic adenocarcinoma and PEN.

RESULTS

From January 1997 to December 2005, 737 patients undergoing initial EUS-FNA evaluation for a pancreatic mass were identified. In the final analysis, 559 patients with 560 FNA-sampled lesions were included. Overall, 442 lesions were pancreatic adenocarcinoma, and 40 were PEN. The sensitivity of EUS-FNA in the diagnosis of pancreatic adenocarcinomas and PENs was 77% (95% CI, 72.8%-80.8%) and 68% (95% CI, 50.8%-80.9%), respectively, using strict cytologic criteria. Reclassification of atypical and suspicious cytologies as diagnostic of malignancy resulted in a sensitivity of 93%, (95% CI, 90.9%-99.7%) in adenocarcinoma and 80% (95% CI, 63.9%-90.4%) in PEN. Tumor size, tumor location, and number of needle passes did not significantly influence diagnosis, but immediate cytologic evaluation was influential.

LIMITATIONS

Retrospective analysis at a single center.

CONCLUSIONS

In a large, well-controlled study, EUS-FNA was found to be an accurate test (80%) for the detection of pancreatic adenocarcinoma by using aspiration cytology. The accuracy of the examination is significantly improved (94%) when atypical and suspicious samples are considered positive. Finally, only 2 to 3 FNA passes may be needed to achieve a good diagnostic yield.

Techniques for thyroid FNA: a synopsis of the National Cancer Institute Thyroid Fine-Needle Aspiration State of the Science Conference

The National Cancer Institute (NCI) sponsored the NCI Thyroid fine-needle aspiration (FNA) State of the Science Conference on October 22-23, 2007 in Bethesda, MD. The 2-day meeting was accompanied by a permanent informational website and several on-line discussion periods between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document summarizes matters addressing manual and ultrasound guided FNA technique and related issues. Specific topics covered include details regarding aspiration needles, devices, and methods, including the use of core needle biopsy; the pros and cons of anesthesia; the influence of thyroid lesion location, size, and characteristics on technique; the role of ultrasound in the FNA of a palpable thyroid nodule; the advantages and disadvantages of various specialists performing a biopsy; the optimal number of passes and tissue preparation methods; sample adequacy criteria for solid and cystic nodules, and management of adverse reactions from the procedure. (http://thyroidfna.cancer.gov/pages/info/agenda/)

Cytological and cyst fluid analysis of small (< or =3 cm) branch duct intraductal papillary mucinous neoplasms adds value to patient management decisions

BACKGROUND/AIM

Management of patients with small (1-3 cm) branch duct intraductal papillary mucinous neoplasms (IPMN) is a challenge. Symptoms, dilated duct, mural nodule or positive cytology have been proposed as parameters for resection. The aim of our study was to compare this proposed algorithm to one that incorporates cytology with less than malignant epithelial cells and cyst fluid carcinoembryonic antigen (CEA).

METHODS

A retrospective study was conducted.

RESULTS

There were 14 nonmalignant and 6 malignant cysts with 3 invasive IPMN. None were associated with a dilated duct and none had positive cytology. Only a mural nodule was significant by univariate analysis for the detection of malignancy (p = 0.01) and invasion (p = 0.009). The detection of atypical epithelial cells or a cyst fluid CEA of >2,500 ng/ml was more accurate for the detection of malignancy than using the recommended algorithm.

CONCLUSIONS

The presence of a mural nodule in a small branch duct IPMN is a predictor of malignancy and invasion by univariate analysis. Recognition of an atypical epithelial cell component in contrast to positive cytology or a cyst fluid CEA of >2,500 ng/ml is more accurate than the recommended algorithm and adds value to the preoperative assessment of clinically diagnosed small branch duct IPMN. and IAP.

Endoscopic ultrasound-guided fine needle aspiration cytology of the pancreas: a morphological and multimodal approach to the diagnosis of solid and cystic mass lesions

Cytological evaluation of pancreatic masses and cysts is the preferred pre-operative diagnostic modality and is increasingly being performed by endoscopic ultrasound. This review focuses on the multimodal approach at the Massachusetts General Hospital that utilizes clinical, cytological, radiological and ancillary studies in rendering a final cytological diagnosis.

Intraductal papillary mucinous neoplasm of the pancreas: cytologic features predict histologic grade

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is an increasingly recognized cystic neoplasm of the pancreas, histologically classified by the degree of epithelial atypia and by the presence or absence of invasion of the cyst wall. To the authors' knowledge, the cytologic features of this neoplasm are poorly characterized, especially with respect to tumor grade.

METHODS

Thirty-three endoscopic ultrasound (EUS)-guided pancreatic fine-needle aspiration biopsy (FNAB) samples and 1 pancreatic duct brush specimen from 25 patients with a histologically confirmed IPMN were retrospectively reviewed. Blinded to tumor grade, background mucin, inflammation, necrosis, overall cellularity, the presence of gastrointestinal-contaminating epithelium, architecture of cell clusters, and nuclear and cellular morphology were evaluated. In cases in which special stains for mucin were performed, the diagnostic utility of these stains was assessed. These cytologic features were subsequently correlated with the histologic diagnosis.

RESULTS

The 34 cytology samples represented 4 adenomas, 15 IPMN-moderate dysplasias, 7 intraductal carcinomas, and 8 IPMNs with invasive carcinoma. Extracellular mucin was present in 97% of all cases; 53% had thick, viscous, "colloid-like" mucin. Special stains for mucin were positive in 6 of 11 cases (54%), helping to identify thin mucin in only 2 cases. Gastrointestinal contamination did not appear to create diagnostic difficulty due to an apparent dual (dysplastic-nondysplastic) epithelial population, but only 4 adenomas were evaluated in this study. Necrosis distinguished IPMN with carcinoma from IPMN-adenomas and IPMN with moderate dysplasia (P < .00001), and was more often observed with invasion than IPMN-carcinoma in situ (P < .05). Tight epithelial cell clusters with hyperchromatic nuclei and a high nuclear to cytoplasmic ratio was more significant in IPMN of at least moderate dysplasia (P = .03). Pale nuclei with parachromatin clearing was found to be a nuclear feature that was suspicious for at least carcinoma in situ (P < .001). In addition, significant background inflammation (neutrophils and histiocytes) was found to be more characteristic of IPMN with at least carcinoma in situ (P = .002).

CONCLUSIONS

The presence of thick, "colloid-like" mucin is noted in half of the IPMN cases, but was not found to be specific to grade. The absence of such mucin does not exclude an IPMN. The presence of tight epithelial cell clusters is consistent with a neoplasm of at least moderate dysplasia, and abundant background inflammation and parachromatin clearing correlated with the presence of at least carcinoma in situ. Necrosis was the only feature found to be strongly suggestive of invasion.

Bronchogenic cyst of the gastric fundus presenting as a gastrointestinal stromal tumor

Gastrointestinal stromal tumors (GIST) of the stomach are being recognized with increasing frequency. The diagnosis is usually made on the basis of appearance on computed tomography (CT) and excision is recommended for GIST larger than 5 cm. We report a 39-year-old woman referred for resection of a presumed GIST of the gastric fundus diagnosed by CT scan and upper gastrointestinal (UGI) series. A laparoscopic resection was performed, but upon pathologic examination the mass proved to be a bronchogenic duplication cyst of the stomach. Bronchogenic and esophageal duplication cysts usually arise in the chest or mediastinum. On rare occasions bronchogenic cysts may lose their connection to the tracheobronchial tree and migrate to a subcutaneous position in the neck or descend into the retroperitoneum. The importance of this case is that it demonstrates a rare yet essential component to the differential diagnosis of lesions of the stomach.

The fine-needle aspiration biopsy cytology of pancreatoblastoma

We describe the clinical, cytological, histological, and immunohistochemical features of primary and metastatic pancreatoblastoma (PBL), a rare primary pancreatic malignancy of both adults and children. An 18-yr-old male patient presented with abdominal pain, weight loss, and diarrhea and had a 9-cm pancreatic mass that was revealed by CT scan. The fine-needle aspiration biopsy (FNAB) smears from the pancreas specimen and the lung metastasis were cellular and were composed of a combination of solid sheets, three-dimensional, loosely cohesive epithelial groups, and primitive spindled mesenchymal tissue with focal cartilage formation. Acinar formations were best appreciated on cell block preparations, and squamoid corpuscles were seen only on cell block. Zymogen granules were demonstrated in a subset of the epithelial cells using periodic-acid Schiff stains with and without diastase and dual acinar-endocrine differentiation was evident using a focused panel of immunohistochemical stains. Acinar-cell carcinoma (ACC) is the most difficult neoplasm to distinguish from PBL, both clinically and cytologically, especially in young children. The key to distinguishing them is to note the presence of squamous corpuscles and/or heterologous elements such as cartilage. Given the increasing utility of FNAB in the investigation of pancreatic masses, it is important for the pathologist to be familiar with the morphological features of this tumor, especially because preoperative diagnosis provides an opportunity for preoperative therapy before resection.

Reducing or eliminating use of the category of atypical squamous cells of undetermined significance decreases the diagnostic accuracy of the Papanicolaou smear

BACKGROUND

The diagnosis of "atypical squamous cells of undetermined significance" (ASCUS) is controversial, not only for the clinical utility of its subcategories (favor reactive vs. favor dysplasia), but for its very existence as an expression of uncertainty. In the current study, the authors investigated the impact of reducing and eliminating this category on the sensitivity and predictive values for detecting squamous intraepithelial lesions (SILs).

METHODS

One hundred cervical Papanicolaou (Pap) smears originally diagnosed as ASCUS, all of which had histologic follow-up, were reviewed blindly and reclassified as either negative (within normal limits/benign cellular changes), low-grade SIL (LSIL), or high-grade SIL (HSIL) by 1 reviewer who eliminated ASCUS as a diagnostic possibility entirely. A second reviewer reinterpreted the cases but attempted to use the ASCUS diagnosis (favor reactive or favor dysplasia) sparingly. All histologic diagnoses were reviewed, and an adjudicated final diagnosis was established. Reviewed smear interpretations were correlated with the histologic diagnosis (original, reviewed, and adjudicated). Statistical analysis was performed using the Fisher exact test.

RESULTS

Thirty-eight women had histologically confirmed SIL (21 LSIL cases and 17 HSIL cases [including 1 case of endocervical adenocarcinoma]); 31 of these 38 cases originally were classified as ASCUS, not otherwise specified, 1 case was classified as ASCUS favor reactive, and 6 cases were classified as ASCUS favor dysplasia. The reviewer who used the ASCUS diagnosis sparingly reclassified the smears as negative (62 cases); ASCUS, favor reactive (3 cases); ASCUS, favor dysplasia (13 cases); LSIL (19 cases); and HSIL (3 cases). The reviewer who eliminated the ASCUS category reclassified the smears as negative (59 cases), LSIL (29 cases), and HSIL (12 cases). The rate of SIL/HSIL in those cases interpreted as abnormal was 38%/17% originally, 42%/24% with a reduced ASCUS interpretation, and 37%/17% when the ASCUS category was eliminated. In those ASCUS smears that were reclassified as negative, the SIL/HSIL rate was 35%/13% with the reduced ASCUS interpretation and 39%/17% when the ASCUS category was eliminated. The sensitivity for detecting a SIL/HSIL was reduced from 100%/100% for the original ASCUS interpretation to 42%/53% for the reduced ASCUS interpretation to 39%/41% with the elimination of the ASCUS interpretation.

CONCLUSIONS

Although in the current study utilization of the ASCUS diagnosis was found to result in a 62% negative or reactive outcome on biopsy, a significant number of patients with SIL were detected (38% in the current series, 17% with HSIL). Despite the improved correlation with negative biopsies, reducing or eliminating the ASCUS diagnosis appears to decrease the sensitivity of the Pap smear significantly and appears to be no better than chance at predicting a diagnosis of SIL on biopsy, including HSIL.

Malignant melanoma with a myxoid stroma: a diagnostic pitfall on fine-needle aspiration biopsy

Malignant melanoma (MM), both primary and metastatic, may be associated with a prominent myxoid stromal reaction causing diagnostic confusion on fine-needle aspiration biopsy (FNAB), most often with sarcomas that demonstrate a myxoid stroma, particularly malignant peripheral nerve sheath tumor (MPNST). We present a case of a 32-yr-old man with no past medical history who presented with a unilateral neck mass clinically suspicious for lymphoma. FNAB produced a specimen composed of large sheets of anaplastic cells encased in a myxoid stroma that was S100 and vimentin-positive but HMB-45-negative. A diagnosis of MPNST was made. Excision demonstrated a metastatic MM of unknown primary, with a prominent myxoid stromal reaction. A repeat HMB-45 was again negative. Electron microscopy demonstrated intracytoplasmic melanasomes and cisternae of rough endoplasmic reticulum with intracisternal parallel tubules, confirming the diagnosis. Although HMB-45 is typically negative in both tumors, S100 should be strongly positive in myxoid MM and only focal in MPNST.

Fine-Needle Aspiration Biopsy in the Diagnosis and Classification of Primary and Recurrent Lymphoma: A Retrospective Analysis of the Utility of Cytomorphology and Flow Cytometry

We retrospectively reviewed our experience with the fine-needle aspiration biopsy (FNAB) diagnosis of primary and recurrent lymphoma to assess the ability of cytomorphology with and without ancillary flow cytometry (FCM) analysis to diagnose and subclassify these tumors according to the Revised European-American Lymphoma/World Health Organization classifications. We reviewed 139 consecutive FNABS of 84 primary and 55 recurrent lymphomas. FCM was successful in 105 (75%) cases. The overall results, including cases without FCM, included 93/139 (67%) true positive, 7 (5%) false negative, and 39 indeterminate (27 [19%] suspicious and 12 [9%] atypical) diagnoses of lymphoma. In cases with FCM, there were 80/105 (77%) true positive, no false negative, and 25 indeterminate diagnoses (15 [14%] suspicious and 10 [9%] atypical). The overall results of the 84 primary lymphomas were 55 (67%) true positive, 5 (5%) false negative, and 24 indeterminate (14[16%] suspicious and 10 [12%] atypical) diagnoses for lymphoma. Of the 68 primary lymphomas analyzed with FCM, 50 [74%] were true positives, and 28 were indeterminate (11 [16%] suspicious and 7 [10%] atypical). There were no false negatives. Diagnostic accuracy varied among lymphoma subtypes. Subclassification of the positive cases were initially conclusive in only 55/93 cases (59%). However, a retrospective review of the morphologic together with FCM data in 15 of the 23 unclassified cases improved the overall subclassification of positive cases to 77%. Subclassification was best in small lymphocytic lymphoma/chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, Burkitt's lymphoma, mantle cell lymphoma, and plasmacytoma (all 100%). Subclassification was poor in marginal-zone lymphoma (33%), and initially as well in diffuse large B-cell lymphoma (62%), but it improved on review (95%), as did subclassification of follicular lymphoma (77 to 100% on review). Hodgkin's disease was recognized as malignant in only 44% of the cases (7/16) and was classified as such based on morphology alone. This review of our early efforts to diagnose and subclassify lymphoma with FNAB and FCM indicates that although a diagnosis and proper subclassification of lymphoma can be made with certainty in the majority of cases, recurrent or primary, it requires close coordination of cytomorphology and immunophenotyping data, which often comes with close cooperation of cytopathologists and hematopathologists. A mere cytological diagnosis of positive for lymphoma is no longer acceptable if FNAB is to become an independent diagnostic tool for lymphoma.

Fine-needle aspiration biopsy of papillary thyroid carcinoma: diagnostic utility of cytokeratin 19 immunostaining

BACKGROUND

Papillary thyroid carcinoma is the most common malignant neoplasm of the thyroid gland, and fine-needle aspiration biopsy (FNAB) often is the initial diagnostic method used in its detection. Prior studies have shown that immunohistochemical staining for various cytokeratins in general, and cytokeratin 19 (CK19) in particular, can be applied as an ancillary technique for diagnosing papillary thyroid carcinoma in histologic specimens. In the current study the authors assessed the diagnostic utility of CK19 to detect papillary carcinoma effectively in cytologic preparations of thyroid FNABs.

METHODS

Immunocytochemical staining with CK19 was performed on cytologic aspirates from 37 papillary thyroid carcinomas and 36 other lesions of the thyroid (14 follicular adenomas, 10 multinodular goiters, 5 cases of Hashimoto thyroiditis, 6 oncocytic [Hürthle cell] neoplasms, and 1 follicular carcinoma). All cases included in the study had a corresponding histopathology specimen.

RESULTS

Positive immunocytochemical reactivity for CK19 was identified in 34 of 37 papillary carcinomas and in 1 of 36 other thyroid lesions (sensitivity of 92% and specificity of 97%). Although the strongest reactivity was obtained in methanol fixed thin layer preparations, the antibody also was effective in detecting papillary carcinoma in alcohol fixed and air-dried smears. The single false-positive case was a follicular adenoma with focal areas of papillary hyperplasia. All other aspirates including those from cases of Hashimoto thyroiditis, multinodular goiter, follicular adenoma, oncocytic neoplasms, and follicular carcinoma were negative.

CONCLUSIONS

CK19 is an effective, highly sensitive, and specific ancillary tool for the diagnosis of papillary carcinoma in thyroid FNABs.

The clinical application and cost analysis of fine-needle aspiration biopsy in the diagnosis of mass lesions in sarcoidosis

BACKGROUND

Sarcoidosis is a prevalent disease of unknown cause characterized by granulomatous inflammation that often creates deep and/or superficial mass lesions. Tissue samples are considered the "gold standard" in diagnosis; however, it is a medically treated disease. We analyzed the utility and relative cost-effectiveness of fine-needle aspiration biopsy (FNAB) in the clinical investigation of patients with both suspected and unsuspected sarcoidosis.

METHODS

All FNAB cases with sarcoidosis either as the cytologic diagnosis or mentioned as part of the differential diagnosis were retrospectively reviewed for clinical history, follow-up, cytologic features, and surgical pathology findings. Comparative analysis of cost of FNAB and excisional biopsy were also made.

RESULTS

Thirty-two FNABs in 28 patients included 17 women and 11 men. Anatomic sites included lymph node (n = 17), lung (n = 5), salivary gland (n = 8), and liver (n = 2). Sarcoidosis had already been diagnosed or was a clinical consideration prior to FNAB in 14 cases. Chest radiograph showed abnormal findings in 19 cases. Angiotensin-converting enzyme (ACE) was measured in seven patients and was elevated in four. All aspirates showed granulomatous inflammation; in 22 patients, special stains or cultures for microorganisms were negative. Simultaneous or subsequent excisional biopsies confirmed the FNAB findings in 17 patients. Institutional ratios of excisional biopsy to FNAB in the diagnosis of sarcoidosis ranged from 4 to 19:1. The cost of FNAB was only 12.5 to 50% that of tissue biopsy.

CONCLUSIONS

FNAB appears to be underutilized in the diagnosis of sarcoidosis. When used in conjunction with radiologic and laboratory data, FNAB may be a reliable and cost-effective method of diagnosis, especially in patients with an established diagnosis of sarcoidosis.

Cytologic features of metastatic sebaceous carcinoma: report of two cases with comparison to three cases of basal cell carcinoma

The cytologic findings of two cases of metastatic sebaceous carcinoma are described and compared to three cases of locally recurrent basal cell carcinoma. Morphological findings for sebaceous carcinoma in fine-needle aspiration biopsy (FNAB) smears included cellular, loosely cohesive cell clusters with central necrosis, squamous pearl formation, and adjacent keratin debris. The tumor cells had moderate amounts of vacuolated cytoplasm, round to oval vesicular nuclei with clumped chromatin, nucleoli, some nuclear overlap, and numerous mitotic figures. An interesting finding was the presence of numerous multinucleated giant cells, probably responding to extravasated lipid or keratin material. In contrast, the FNAB smears of basal cell carcinoma typically were less cellular, with more tightly cohesive and smaller clusters of uniform hyperchromatic basaloid cells with high nuclear to cytoplasmic ratios, and a narrow rim of cytoplasm without vacuolization. The morphologic features of sebaceous carcinoma in FNAB smears appear to be distinct from those of basal cell carcinoma. FNAB can be a useful preoperative diagnostic technique to distinguish these two cutaneous malignancies.

Ultrasound-guided fine-needle aspiration biopsy of the thyroid

BACKGROUND

We reviewed the Massachusetts General Hospital experience with ultrasound-guided fine-needle aspiration biopsies (FNABs) of the thyroid to determine the indications, rate of unsatisfactory smears, correlation with excisional biopsy results, and verification of efficient use of personnel time.

METHODS

All radiologically guided FNABs of the thyroid from January 1993 through June 1997 were reviewed. As a measure of efficient use of technologist time, a sample of times spent by the technologist during the procedure for 20 cases in 1993 and 1997 was compared with that of an equal number of random nonthyroid image guided FNABs.

RESULTS

Two hundred-ninety FNABs were identified in 251 patients, representing 12% of all thyroid FNABs and 11% of all radiologically guided FNABs. Indications in the 251 patients included multiple nodules (78), solitary nodules (61), complex nodules (39), prior failed FNAB (39), thyroid bed abnormalities post-thyroidectomy (21), difficult access (7), and investigation of recurrent tumor in residual thyroid lobe (6). Available records indicated 118 lesions were palpable and 45 were nonpalpable; the physical examination characteristics of the remainder (88) were not stated. Diagnoses included 44 unsatisfactory cases (15%), 103 macrofollicular lesions, 20 microfollicular lesions, 26 mixed macro/microfollicular lesions, 5 oxyphilic lesions, 1 trabecular pattern, 15 nonspecific follicular cell pattern, 9 follicular cell atypia, 30 cysts, 11 thyroiditis, 23 malignant tumors, and 3 other (1 parathyroid, 2 lymph node). Eighty-nine FNABs from 76 patients had subsequent surgical biopsy. Excisional biopsies in 14 unsatisfactory FNABs were benign. In the remaining 75 FNABs from 67 patients, 18 malignancies on FNAB were correctly diagnosed, but 3 other papillary carcinomas were only qualified as atypical follicular cells on cytology. No false-positive cases occurred. Of 15 macrofollicular lesions on cytology, 10 were adenomas on excision, only 2 of which were microfollicular adenomas, and 4 were adenomatous nodules. An aspirate of a parathyroid adenoma was misinterpreted as a macrofollicular lesion of the thyroid. Three microfollicular lesions on FNAB proved to be nodular hyperplasia on excision, and the other 11 were adenomas, 5 of them microfollicular. Average technologist time was significantly longer for thyroid FNABs than nonthyroid FNABs in 1993, but in the 1997 sample no significant difference was identified.

CONCLUSIONS

Radiologically guided FNAB of the thyroid is a clinically useful procedure with a high correlation between benign lesions not needing excision (macrofollicular), and lesions that need excision (microfollicular/oxyphilic cell or malignant). Technologist time needed for immediate evaluation tends to decrease with increasing operator experience. Cancer (Cancer Cytopathol)

Urine cytology of primary and secondary urinary bladder adenocarcinoma

BACKGROUND

Primary and secondary adenocarcinomas of the urinary bladder are uncommon, and the urine cytology of these tumors has rarely been described. Familiarity with the cytomorphology of these neoplasms may facilitate their detection in urine cytology specimens.

METHODS

The authors reviewed 46 urine samples (19 voided, 19 instrumented, and 8 bladder washings) from 41 patients with biopsy-proven primary urinary bladder adenocarcinoma (n = 11) or metastatic adenocarcinoma (n = 35) from the prostate (n = 17), colon (n = 10), breast (n = 3), kidney (n = 3), or uterus (n = 1), or from unknown origin (n = 1). Cytomorphology, the role of cytology, and causes for negative diagnoses were evaluated.

RESULTS

Cytologic diagnoses of malignancy, adenocarcinoma not otherwise specified, and adenocarcinoma of a specific type were given in 87%, 28%, and 39% of cases, respectively. Columnar cells, coarse chromatin, and necrosis were found in adenocarcinoma of the colon. Syncytial and acinar arrangements, round or oval nuclei, vesicular chromatin, and prominent nucleoli were commonly found in adenocarcinoma of the prostate. These features permitted us to make a specific diagnosis in 90% of cases of adenocarcinoma of the colon and 41% of cases of adenocarcinoma of the prostate. Cytologic examination failed to lead to a diagnosis of malignancy in 18% of primary adenocarcinoma cases.

CONCLUSIONS

A large number of adenocarcinomas of the colon and prostate have sufficient cytologic features to suggest the correct diagnosis in urine samples. The cytomorphology of primary bladder adenocarcinoma is not as easily characterized. The submucosal nature of some metastatic deposits and tumor differentiation influence the diagnostic accuracy.

Benign glandular cells in posthysterectomy vaginal smears

OBJECTIVE

To investigate the occurrence and origin of benign glandular cells in posthysterectomy vaginal smears and to propose a categorization for these cells under the Bethesda system.

STUDY DESIGN

Among 4,986 posthysterectomy vaginal smears during a 3.5-year period, 82 patients were identified with smears containing benign glandular cells. The review of the smears, related biopsies and charts form the basis of this report. A control group of 236 posthysterectomy smears without glandular cells from the same period was reviewed.

RESULTS

Smears were available for review on 76 of 82 patients. All were within normal limits or showed benign cellular changes. All contained clearly benign glandular cells, most frequently present in groups. In all smears, pale pink-red intracellular mucin was identified either diffusely within the cytoplasm or within vacuoles. The glandular cells appeared as hybrid parabasal-endocervical type, squamous metaplastic or columnar cells. Associated cytologic findings included atrophy, inflammation, blood and repair. Reactive atypia was present in 10 (13%) cases. Biopsies were performed on 40 (48%), all showing benign changes. In four of five cases stained, intracellular mucin was seen within glandular cells. Chart review revealed that the patients' hysterectomies were performed for removal of a malignant tumor in 58 (71%) of the study group and in 100 (42%) in the comparison group and that 48 (58%) of the study group had received radiotherapy and/or chemotherapy, while only 26 (11%) of those in the comparison group had similar therapy.

CONCLUSION

The presence of benign glandular cells in posthysterectomy vaginal smears is an infrequent but not rare finding. This study indicated an association with benign processes and showed a frequent association with prior radiation or chemotherapy. A more appropriate designation under the Bethesda System is "benign cellular changes" rather than "glandular cell abnormalities." An aggressive workup does not appear to be warranted in this group of patients. We speculate that this phenomenon represents a metaplastic process, possibly secondary to radiation or chemotherapy.