Evaluating the Adoption of Laboratory Practice Guidelines.

CONTEXT.­: To date, the College of American Pathologists (CAP) has developed 17 laboratory practice guidelines (LPGs) including updates. In 2013, the CAP was awarded a 5-year cooperative agreement grant from the United States Centers for Disease Control and Prevention to increase the effectiveness of LPGs. OBJECTIVE.­: To assess the awareness and adoption of 2 CAP LPGs: immunohistochemical (IHC) assay validation and initial workup of acute leukemia. DESIGN.­: Baseline surveys for each LPG were conducted in 2010 and 2015, respectively. To measure the adoption of guideline recommendations and inform future updates, a follow-up study consisting of surveys, telephone interviews, and focus group sessions was conducted in laboratories that indicated they perform IHC testing. A follow-up study for the acute leukemia LPG is planned. RESULTS.­: For the IHC Validation LPG, a total of 1624 survey responses, 40 telephone interviews, and discussions with 5 focus group participants were analyzed. The response rate for the aforementioned 3 modalities was 46%, 13%, and 3%, respectively. All modalities indicated most respondents were aware of the LPG and had adopted most or all of its recommendations. Respondents expressed needs for continued communication, increased specificity, and more prescriptive recommendations when the guideline is updated. CONCLUSIONS.­: While data-driven development of evidence-based LPGs requires significant resources, active data collection to identify gaps and assess adoption contributes to improved laboratory testing practices in support of patient care. The CAP identified sustainable modalities to track metrics and developed multiple tools that should improve guideline development, adoption, and implementation. Of these modalities, written or electronic surveys were the most logistically feasible and had the highest response rate.

Purity Independent Subtyping of Tumors (PurIST), A Clinically Robust, Single-sample Classifier for Tumor Subtyping in Pancreatic Cancer.

PURPOSE: Molecular subtyping for pancreatic cancer has made substantial progress in recent years, facilitating the optimization of existing therapeutic approaches to improve clinical outcomes in pancreatic cancer. With advances in treatment combinations and choices, it is becoming increasingly important to determine ways to place patients on the best therapies upfront. Although various molecular subtyping systems for pancreatic cancer have been proposed, consensus regarding proposed subtypes, as well as their relative clinical utility, remains largely unknown and presents a natural barrier to wider clinical adoption. EXPERIMENTAL DESIGN: We assess three major subtype classification schemas in the context of results from two clinical trials and by meta-analysis of publicly available expression data to assess statistical criteria of subtype robustness and overall clinical relevance. We then developed a single-sample classifier (SSC) using penalized logistic regression based on the most robust and replicable schema. RESULTS: We demonstrate that a tumor-intrinsic two-subtype schema is most robust, replicable, and clinically relevant. We developed Purity Independent Subtyping of Tumors (PurIST), a SSC with robust and highly replicable performance on a wide range of platforms and sample types. We show that PurIST subtypes have meaningful associations with patient prognosis and have significant implications for treatment response to FOLIFIRNOX. CONCLUSIONS: The flexibility and utility of PurIST on low-input samples such as tumor biopsies allows it to be used at the time of diagnosis to facilitate the choice of effective therapies for patients with pancreatic ductal adenocarcinoma and should be considered in the context of future clinical trials.

Prolonged Remission of Cancer of Unknown Primary following Initiation of Eculizumab Therapy for Paroxysmal Nocturnal Hemoglobinuria.

We report the case of a 64-year-old woman who presented with cancer of unknown primary treated with carboplatin and paclitaxel, followed by maintenance erlotinib. Her chemotherapy regimen was discontinued due to the development of profound hemolysis that was later identified to be due to paroxysmal nocturnal hemoglobinuria (PNH). She was started on a complement inhibitory antibody, eculizumab 900 mg every 2 weeks, with marked suppression of hemolysis. Eight years after diagnosis of cancer, the patient remains on eculizumab with no signs of cancer recurrence on regular imaging. Regardless of whether the co-occurrence of cancer and PNH was any more than coincidental in this patient, the uniqueness of the case is emphasized by the remarkable and sustained response of not only PNH but also possibly the associated cancer to eculizumab.

De novo compartment deconvolution and weight estimation of tumor samples using DECODER.

Tumors are mixtures of different compartments. While global gene expression analysis profiles the average expression of all compartments in a sample, identifying the specific contribution of each compartment remains a challenge. With the increasing recognition of the importance of non-neoplastic components, the ability to breakdown the gene expression contribution of each is critical. Here, we develop DECODER, an integrated framework which performs de novo deconvolution and single-sample compartment weight estimation. We use DECODER to deconvolve 33 TCGA tumor RNA-seq data sets and show that it may be applied to other data types including ATAC-seq. We demonstrate that it can be utilized to reproducibly estimate cellular compartment weights in pancreatic cancer that are clinically meaningful. Application of DECODER across cancer types advances the capability of identifying cellular compartments in an unknown sample and may have implications for identifying the tumor of origin for cancers of unknown primary.

Stromal Content Is Correlated With Tissue Site, Contrast Retention, and Survival in Pancreatic Adenocarcinoma.

PURPOSE: Desmoplastic stroma is a cardinal feature of primary pancreatic ductal adenocarcinoma (PDAC), but its effects on the biology, prognosis and therapeutic outcomes are not known. We developed an automated method to assess tumor stroma density (TSD) and investigated computed tomography (CT)-correlates of stroma in PDAC. PATIENTS AND METHODS: We collected PDAC samples from rapid autopsy and resection series and digitally annotated samples to quantify TSD. A series of resected patients also underwent preoperative multiphasic CT. RESULTS: Automated and manual assessments of TSD were highly correlated (ρ= 0.65, P < 0.001). Solid organ metastases had a lower median TSD than primary tumors (P < 0.001). Patients with high TSD enjoyed prolonged recurrence free survival (RFS) (P = 0.003; HR = 0.51) and overall survival (P = 0.008, HR = 0.57). In another independent dataset, patients with high TSD had decreased risk for recurrence (P = 0.003, HR = 0.03) and death (P = 0.003, HR = 0.03) at time of resection, however the protective effect diminished over time. Patients with normalized portovenous phase CT tumor enhancement ratio ≥0.40 had a longer RFS following resection (P = 0.020). Normalized portovenous phase CT tumor enhancement ratio was significantly correlated with TSD (P = 0.003). CONCLUSIONS: Objective quantitative assessment of stroma in PDAC revealed several clinically relevant observations. Firstly, stroma was less abundant in metastatic PDAC, the cause of most PDAC mortality. Secondly, high stromal content correlates with favorable outcome in resected cases, implying a protective effect of stroma and suggesting careful consideration of active stromal depletion therapies. Finally, standard multiphase CT imaging correlates with stroma content as well as clinical outcome, indicating that non-invasive assessment of stroma is a feasible sensitivity enrichment approach in PDAC.

Interpathologist Diagnostic Agreement for Non-Small Cell Lung Carcinomas Using Current and Recent Classifications.

CONTEXT.­: Measurement of interpathologist diagnostic agreement (IPDA) should allow pathologists to improve current diagnostic criteria and disease classifications. OBJECTIVES.­: To determine how IPDA for pathologists' diagnoses of non-small cell lung carcinoma (NSCLC) is affected by the addition of a set of mucin and immunohistochemical (IHC) stains to hematoxylin-eosin (H&E) alone, by recent NSCLC reclassifications, by simplification of these classifications, and by pathologists' practice location, pulmonary pathology expertise, practice duration, and lung carcinoma case exposure. DESIGN.­: We used a Web-based survey to present core images of 54 NSCLC cases to 22 practicing pathologists for diagnosis, initially as H&E only, then as H&E plus mucin and 4 IHC stains. Each case was diagnosed according to published 2004, 2011, and 2015 NSCLC classifications. Cohen's kappa was calculated for the 231 pathologist pairs as a measure of IPDA. RESULTS.­: Twenty-two pathologists diagnosed 54 NSCLC cases by using 4 published classifications. IPDA is significantly higher for H&E/mucin/IHC diagnoses than for H&E-only diagnoses. IPDA for H&E/mucin/IHC diagnoses is highest with the 2015 classification. IPDA is estimated higher after collapse of stated diagnoses into subhead or dichotomized classes. IPDA for H&E/mucin/IHC diagnoses with the 2015 World Health Organization classification is similar for community and academic pathologists, and is higher when pathologists have pulmonary pathology expertise, have more than 6 years of practice experience, or diagnose more than 100 new lung carcinoma cases per year. CONCLUSIONS.­: Higher IPDA is associated with use of mucin and IHC stains, with the 2015 NSCLC classification, and with pathologists' pulmonary pathology expertise, practice duration, and frequency of lung carcinoma cases.

Molecular diagnostic testing as an adjunct to morphologic evaluation of pancreatic ductal system brushings: potential augmentation for diagnostic sensitivity.

Malignancies arising from the pancreatic and biliary ductal systems present the gastroenterologist and pathologist with diagnostic challenges. Tumors of the pancreatic and/or biliary ductal system may present as either duct strictures or mass lesions. When lesions present as strictures without associated demonstrable masses, brushing cytology may represent the only reasonable diagnostic technique aside from open biopsy. Diagnostic sensitivities for brushing cytology have ranged from 18 to 90%. Positive diagnoses of malignancy are of great clinical value but a negative result is of relatively little clinical aid when the radiographic or clinical findings are suspicious for a malignancy.A variety of techniques have been used in an attempt to improve diagnostic sensitivity for brushing cytology. These have included immunohistochemistry and various molecular diagnostic techniques. Using the high resolution melting curve technique, we performed mutational analysis on 20 bile duct brushing specimens for mutations in p53, K-ras, BRAF, and EGFR genes. Eleven specimens had corresponding surgical specimens, which were similarly analyzed. Our series included twelve adenocarcinomas, one islet cell tumor, one case of dysplasia, and six benign cases. K-ras mutations were found in cytology specimens of 3 out of 12 malignancies. No EGFR or B-raf mutations were detected and only a single p53 mutation in an adenocarcinoma was detected in the corresponding cytology specimen. No mutations were detected in benign lesions or in the dysplasia. Only 8% of specimens from adenocarcinomas had p53 mutations and only 33% of cases had K-ras mutations. Mutational analysis did not appear to improve the cytologic detection of adenocarcinoma by bile duct brushings.

Analytic Validation of Immunohistochemistry Assays: New Benchmark Data From a Survey of 1085 Laboratories.

CONTEXT: - A cooperative agreement between the College of American Pathologists (CAP) and the United States Centers for Disease Control and Prevention was undertaken to measure laboratories' awareness and implementation of an evidence-based laboratory practice guideline (LPG) on immunohistochemical (IHC) validation practices published in 2014. OBJECTIVE: - To establish new benchmark data on IHC laboratory practices. DESIGN: - A 2015 survey on IHC assay validation practices was sent to laboratories subscribed to specific CAP proficiency testing programs and to additional nonsubscribing laboratories that perform IHC testing. Specific questions were designed to capture laboratory practices not addressed in a 2010 survey. RESULTS: - The analysis was based on responses from 1085 laboratories that perform IHC staining. Ninety-six percent (809 of 844) always documented validation of IHC assays. Sixty percent (648 of 1078) had separate procedures for predictive and nonpredictive markers, 42.7% (220 of 515) had procedures for laboratory-developed tests, 50% (349 of 697) had procedures for testing cytologic specimens, and 46.2% (363 of 785) had procedures for testing decalcified specimens. Minimum case numbers were specified by 85.9% (720 of 838) of laboratories for nonpredictive markers and 76% (584 of 768) for predictive markers. Median concordance requirements were 95% for both types. For initial validation, 75.4% (538 of 714) of laboratories adopted the 20-case minimum for nonpredictive markers and 45.9% (266 of 579) adopted the 40-case minimum for predictive markers as outlined in the 2014 LPG. The most common method for validation was correlation with morphology and expected results. Laboratories also reported which assay changes necessitated revalidation and their minimum case requirements. CONCLUSIONS: - Benchmark data on current IHC validation practices and procedures may help laboratories understand the issues and influence further refinement of LPG recommendations.

Analytic Validation of Immunohistochemical Assays: A Comparison of Laboratory Practices Before and After Introduction of an Evidence-Based Guideline.

CONTEXT: - Laboratories must demonstrate analytic validity before any test can be used clinically, but studies have shown inconsistent practices in immunohistochemical assay validation. OBJECTIVE: - To assess changes in immunohistochemistry analytic validation practices after publication of an evidence-based laboratory practice guideline. DESIGN: - A survey on current immunohistochemistry assay validation practices and on the awareness and adoption of a recently published guideline was sent to subscribers enrolled in one of 3 relevant College of American Pathologists proficiency testing programs and to additional nonsubscribing laboratories that perform immunohistochemical testing. The results were compared with an earlier survey of validation practices. RESULTS: - Analysis was based on responses from 1085 laboratories that perform immunohistochemical staining. Of 1057 responses, 65.4% (691) were aware of the guideline recommendations before this survey was sent and 79.9% (550 of 688) of those have already adopted some or all of the recommendations. Compared with the 2010 survey, a significant number of laboratories now have written validation procedures for both predictive and nonpredictive marker assays and specifications for the minimum numbers of cases needed for validation. There was also significant improvement in compliance with validation requirements, with 99% (100 of 102) having validated their most recently introduced predictive marker assay, compared with 74.9% (326 of 435) in 2010. The difficulty in finding validation cases for rare antigens and resource limitations were cited as the biggest challenges in implementing the guideline. CONCLUSIONS: - Dissemination of the 2014 evidence-based guideline validation practices had a positive impact on laboratory performance; some or all of the recommendations have been adopted by nearly 80% of respondents.

Professional Practice Evaluation for Pathologists: The Development, Life, and Death of the Evalumetrics Program.

CONTEXT: - In 2008, the Joint Commission (JC) implemented a standard mandating formal monitoring of physician professional performance as part of the process of granting and maintaining practice privileges. OBJECTIVE: - To create a pathology-specific management tool to aid pathologists in constructing a professional practice-monitoring program, thereby meeting the JC mandate. DESIGN: - A total of 105 College of American Pathologists (CAP)-defined metrics were created. Metrics were based on the job descriptions of pathologists' duties in the laboratory, and metric development was aided by experience from the Q-Probes and Q-Tracks programs. The program was offered in a Web-based format, allowing secure data entry, customization of metrics, and central data collection for future benchmarking. RESULTS: - The program was live for 3 years, with 347 pathologists subscribed from 61 practices (median, 4 per institution; range, 1-35). Subscribers used 93 of the CAP-defined metrics and created 109 custom metrics. The median number of CAP-defined metrics used per pathologist was 5 (range, 1-43), and the median custom-defined metrics per pathologist was 2 (range, 1-5). Most frequently, 1 to 3 metrics were monitored (42.7%), with 20% each following 4 to 6 metrics, 5 to 9 metrics, or greater than 10 metrics. Anatomic pathology metrics were used more commonly than clinical pathology metrics. Owing to low registration, the program was discontinued in 2016. CONCLUSIONS: - Through careful vetting of metrics it was possible to develop a pathologist-specific management tool to address the JC mandate. While this initial product failed, valuable metrics were developed and implementation knowledge was gained that may be used to address new regulatory requirements for emerging value-based payment systems.

Cytomorphology of yolk sac tumor of the liver in fine-needle aspiration: a pediatric case.

Yolk sac tumors (YST) in extragonadal locations are rare. Cytologic diagnosis of YST on fine-needle aspiration (FNA) smears may be a challenge to the cytopathologist. Further neo-adjuvant therapy may be based on cytologic diagnosis making accuracy important. We studied FNA material from a hepatic mass in a pediatric patient to further define the cytomorphologic features of hepatic YST. Features include large pleomorphic balls of tumor cells with high nuclear to cytoplasmic ratios, papillary or microglandular pattern of growth, cytoplasmic and intranuclear vacuoles, and prominent nucleoli. Positive immunohistochemical studies included alpha-fetoprotein, cytokeratin AE1/AE3, and CAM 5.2, which are useful in supporting the diagnosis. We report a pediatric patient in whom the diagnosis of hepatic YST was made by cytologic, histologic, and immunohistochemical studies. The subsequent liver biopsy was consistent with the FNA diagnosis. Our findings may further help to characterize the cytomorphologic features of this rare lesion.

Fine needle aspiration of pancreatic cysts: Use of ancillary studies and difficulty in identifying surgical candidates.

OBJECTIVE: To evaluate ancillary biochemical testing after pancreatic cyst fine needle aspiration (FNA) in the clinical setting. STUDY DESIGN: Findings from 110 pancreatic guided FNA were reviewed cysts evaluated by image- and correlated with histology, clinical follow-up and biochemical analysis of cyst fluid and serum. Adequate followup was available for 95. RESULTS: In terms of identifying cysts requiring surgery, FNA showed 55.3% sensitivity, 95% specificity, 92.9% positive predictive value (PPV) and 64.4% negative predictive value (NPV). FNA showed only nonspecific cyst contents in 51% of cases, but 40% of those patients proved to be surgical candidates at follow-up. Overall, patients with lesions requiring surgery were younger (p = 0.14), more often presented with pain (p = 0.006), had larger cysts (p = 0.05) and less often had a history of chronic pancreatitis (p = 0.12). Among cases in which FNA showed only nonspecific cyst contents, patients with lesions requiring surgery were more often female (p = 0.08), were younger (p = 0.10), had larger cysts (p = 0.06) and had pain at presentation (p = 0.02). Differences in fluid and serum analytes were not statistically significant. CONCLUSION: FNA of pancreatic cysts shows high specificity but poor sensitivity, even with cyst fluid and serum biochemical analysis. FNA of cysts requiring surgery often yielded nonspecific cyst cytology and causing a misinterpretation as pseudocysts. Ancillary biochemical analysis of cyst fluid remains problematic in the clinical setting.

Molecular Testing in Anatomic Pathology and Adherence to Guidelines: A College of American Pathologists Q-Probes Study of 2230 Testing Events Reported by 26 Institutions.

CONTEXT: The appropriate and timely performance of molecular testing in anatomic pathology is an indicator of quality. The National Comprehensive Cancer Network (NCCN) publishes a comprehensive treatment guideline that includes recommendations for ancillary testing. OBJECTIVE: To establish benchmarks for rates of adherence to NCCN testing recommendations through a multi-institutional study. DESIGN: Participants in a 2013 Q-Probes study of the College of American Pathologists reported data from molecular testing on anatomic pathology cases, excluding hematolymphoid neoplasms, breast primary carcinomas, and gynecologic cytology. RESULTS: Twenty-six institutions reported data from 2230 molecular testing events. In a retrospective study limited to colon, lung, and melanoma, there was strict adherence to guidelines in a median 71% (10th to 90th percentile range, 33%-90%) and there was at least loose adherence in a median 95% (10th to 90th percentile range, 57%-100%). There was adequate tissue to complete testing in a median 98% (10th to 90th percentile range, 86%-100%); in aggregate the adequacy rate for cell blocks was lower (84%, P < .001). Median test turnaround time was 8 days (10th to 90th percentile range, 4-13 days). In a prospective collection of all organ sites, there was strict adherence to guidelines in a median 53% (10th to 90th percentile range, 20%-71%), and there was at least loose adherence in a median 94% (10th to 90th percentile range, 75%-100%). Adherence to guidelines was higher for lung specimens and in institutions with more multidisciplinary conferences. CONCLUSIONS: This multi-institutional study provides benchmarking data on appropriateness and timeliness of molecular testing in anatomic pathology.

Turnaround time for large or complex specimens in surgical pathology: a College of American Pathologists Q-Probes study of 56 institutions.

CONTEXT: Turnaround time (TAT) for large or complex surgical pathology specimens is an indicator of efficiency in anatomic pathology and may affect coordination of patient care. OBJECTIVE: To establish benchmarks for TAT and to identify practice characteristics that may influence TAT. DESIGN: Participants in a 2012 Q-Probes quality improvement program of the College of American Pathologists retrospectively reviewed all surgical pathology cases from the prior 6 months to identify up to 50 cases coded as Current Procedural Terminology (CPT) code 88307 (excluding biopsies) or 88309. Participants reported the times and dates of accessioning and final sign-out. RESULTS: A total of 56 institutions reported on 2763 large or complex cases, which included 70% with CPT code 88307 and 30% with CPT code 88309. Cases requiring special handling comprised 51.5%, and 48.5% were routine. Among all institutions the median TAT was 2.72 calendar days (10th-90th percentile range, 6.23-1.22 days). Longer TAT occurred in governmental institutions (median, 6.06 versus 2.13 days; P < .001) and in institutions that mandate overnight fixation for some specimen types (median, 3.83 versus 2.07 days; P = .03). Longer TAT was associated with CPT code 88309 (median, 3.99 versus 2.82 days; P < .001), special handling (median, 4.13 versus 1.94 days; P < .001), frozen section (median, 3.38 versus 2.92 days; P < .001), radical cancer resection (P < .001), and malignant cases (P < .001). Turnaround time was not significantly affected by either pathology training programs or routine weekend sign-out. CONCLUSIONS: This study provides benchmark data for TAT in large or complex surgical pathology specimens. Turnaround time was good overall, but the range among participating institutions was wide.

Virtual microdissection identifies distinct tumor- and stroma-specific subtypes of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) remains a lethal disease with a 5-year survival rate of 4%. A key hallmark of PDAC is extensive stromal involvement, which makes capturing precise tumor-specific molecular information difficult. Here we have overcome this problem by applying blind source separation to a diverse collection of PDAC gene expression microarray data, including data from primary tumor, metastatic and normal samples. By digitally separating tumor, stromal and normal gene expression, we have identified and validated two tumor subtypes, including a 'basal-like' subtype that has worse outcome and is molecularly similar to basal tumors in bladder and breast cancers. Furthermore, we define 'normal' and 'activated' stromal subtypes, which are independently prognostic. Our results provide new insights into the molecular composition of PDAC, which may be used to tailor therapies or provide decision support in a clinical setting where the choice and timing of therapies are critical.

Florid von Brunn nests mimicking urothelial carcinoma: a morphologic and immunohistochemical comparison to the nested variant of urothelial carcinoma.

Florid von Brunn nests may mimic the nested variant of urothelial carcinoma. We examined formalin-fixed, paraffin-embedded tissue from 21 cases of florid von Brunn nests and 11 cases of nested variant of urothelial carcinoma. Morphologic features were recorded in detail. Also, cases were stained with monoclonal antibodies against MIB-1, p53, p27, and cytokeratin 20. Percentage positivity was calculated by counting 300 to 500 cells from each case. Clinical follow-up information was also obtained. Florid von Brunn nests from the bladder were comprised of large nests with regular spacing, and all the nests extended to the same horizontal level at the base of the proliferation. Central lumen formation was often seen within florid von Brunn nests, at times with cystic dilatation, such that there was a spectrum from proliferating von Brunn nests to cystitis glandularis to cystitis cystica. Small, crowded nests with variable spacing and an infiltrative base characterized nested variant of urothelial carcinoma. Four cases showed detrusor muscle invasion on biopsy with an additional case showing detrusor muscle invasion at cystectomy. One additional patient with nested variant of urothelial carcinoma had distant metastases and another had prostatic invasion. Nine of 21 florid von Brunn nests cases were from either the ureter or renal pelvis, whereas all cases of nested variant of urothelial carcinoma arose in the bladder. The ureteral and pelvic florid von Brunn nest cases showed smaller, more variable nests with irregular spacing closely mimicking nested variant of urothelial carcinoma but had a noninfiltrative base and often areas with either a lobular or linear array. Immunohistochemical studies showed nested variant of urothelial carcinoma to have higher MIB-1 expression (8.8% vs. 2.8%, P = 0.01). Nested variant of urothelial carcinoma had nonsignificantly higher p53 positivity (4.2% vs. 1.5%, P = 0.06) and lower p27 positivity (4.7% vs. 7.8%, P = 0.22). Cytokeratin 20 staining was not discriminatory. However, staining with each antibody was widely variable. Wide variation in staining for MIB-1, p53, p27, and cytokeratin 20 was seen in both florid von Brunn nests and nested variant of urothelial carcinoma, such that except for a few cases, a specific cutoff value could not be determined for diagnostic purposes. The findings underscore the importance of morphologic assessment in the distinction of florid von Brunn nests and nested variant of urothelial carcinoma.

Primary pancreatic lymphoma evaluated by fine-needle aspiration: findings in 14 cases.

Fine-needle aspiration (FNA) is a popular method for evaluating pancreatic lesions. There is considerable literature on FNA evaluation of primary pancreatic carcinomas, but few studies address the FNA diagnosis of primary pancreatic lymphoma. We reviewed 14 cases of atypical lymphoid processes diagnosed by FNA during a 5-year period, constituting 1.3% of a total of 1,050 pancreatic FNA cases. The diagnoses were as follows: 6 large B-cell lymphomas, 4 follicular lymphomas, 3 suggestive of lymphoma, and 1 unclassified B-cell lymphoma. Lymphoid neoplasms manifested in older people (mean age, 64.7 years) as a solitary mass in the pancreatic head, mimicking primary carcinoma. Clonality was confirmed by flow cytometry in 11 cases and immunohistochemical analysis on cell block material in 2. Obtaining diagnostic material often required several passes (average, 3.9 passes; range, 1-8 passes). We conclude that primary pancreatic lymphomas rarely are diagnosed by FNA, tend to be high grade, and clinically and radiographically might mimic primary carcinoma.

Phimosis as a cause of the prune belly syndrome: comparison to a more common pattern of proximal penile urethra obstruction.

The pathogenesis of the prune belly syndrome (PBS) remains controversial, but two theories predominate. The first theory supports an obstructive phenomenon early in gestation leading to irreversible damage to the genitourinary tract and abdominal wall. The second theory suggests mesodermal injury between the 6th and 10th weeks of gestation as the primary abnormality. This paper reports of two fetuses with the PBS phenotype that were examined postmortem at our institution. Thorough examination of the lower urinary tract allowed demonstration of anatomic obstruction of the urethra in both cases. One case illustrated a relatively common pattern of proximal penile urethral obstruction, a flap-like obstruction between the prostatic and penile urethra. The other case provided what we believe to be the first description of PBS caused by severe phimosis.

Metastases in the pancreas from nonhematologic neoplasms: report of 20 cases evaluated by fine-needle aspiration.

We reviewed fine-needle aspiration (FNA) samples of metastatic tumor in the pancreas from nonhematologic neoplasms over a 5-year period. In 1,050 total procedures, 20 metastases were diagnosed: 9 renal-cell carcinomas (RCCs), 3 melanomas, 2 pulmonary small-cell carcinomas, 2 breast carcinomas, 1 prostate carcinoma, 1 colon adenocarcinoma, 1 pulmonary squamous-cell carcinoma, and 1 gastrointestinal stromal tumor. A wide range of latency from primary diagnosis was noted; the longest was RCC at 12.6 years (range, 5-28). Sites of involvement were: 13 heads, 4 bodies, and 3 tails. Eighteen cases presented as a solitary mass. The average size was 4.7 cm (range, 1.5-9.8), and a case of RCC (9.8 cm) was the largest. In seven cases, the clinical and radiographic impression was of a pancreatic primary. We conclude that metastases to the pancreas are rarely diagnosed by FNA and may clinically mimic a pancreatic primary.

Fine-needle aspiration cytology of endometrioid adenofibroma of the ovary.

We report the fine-needle aspiration (FNA) cytology findings of endometrioid adenofibroma arising in the ovary of a 60-year-old woman who presented with vaginal bleeding. Imaging studies revealed a large pelvic mass, which was sampled by computed tomography-guided FNA and core biopsy. The FNA yielded cellular smears composed of bland endometrioid cells and fragments of ovarian-type stroma. The core biopsy showed a biphasic process comprising bland endometrioid glands in a spindle-cell stroma. Immunohistochemical studies performed on the core showed the stroma to be CD10-negative and smooth muscle actin-positive. Subsequent resection of the tumor confirmed the diagnosis and revealed an adenocarcinoma arising in the tumor that was not sampled by FNA. To our knowledge, the cytologic features of ovarian endometrioid adenofibroma have not been previously described.