Concomitant granular cell tumor and balanitis xerotica obliterans of the foreskin: A case report and literature review

AbstractBalanitis xerotica obliterans is a chronic dermatosis that frequently involves the glans penis and the foreskin. Granular cell tumor is a benign tumor that may rarely involve the penis, but involvement of the foreskin is exceedingly rare. It may result in thickening and ulceration of the overlying epidermis, which can mimic squamous cell carcinoma. An association of these two lesions, one very common and one extremely uncommon, arising concomitantly in the penile foreskin has not been previously documented. A 23-year-old patient with phimosis and a subcutaneous foreskin nodule presented for a medical circumcision. The microscopic examination demonstrated balanitis xerotica obliterans and granular cell tumor, occurring in continuity in the foreskin. To our knowledge, this is the first reported example of these two lesions arising simultaneously in the male genitalia

Staging of Prostate Cancer Using Automatic Feature Selection, Sampling and Dempster-Shafer Fusion

A novel technique of automatically selecting the best pairs of features and sampling techniques to predict the stage of prostate cancer is proposed in this study. The problem of class imbalance, which is prominent in most medical data sets is also addressed here. Three feature subsets obtained by the use of principal components analysis (PCA), genetic algorithm (GA) and rough sets (RS) based approaches were also used in the study. The performance of under-sampling, synthetic minority over-sampling technique (SMOTE) and a combination of the two were also investigated and the performance of the obtained models was compared. To combine the classifier outputs, we used the Dempster-Shafer (DS) theory, whereas the actual choice of combined models was made using a GA. We found that the best performance for the overall system resulted from the use of under sampled data combined with rough sets based features modeled as a support vector machine (SVM)

Gene Fusion Characterization of Rare Aggressive Prostate Cancer Variants ‐ Adenosquamous Carcinoma, Pleomorphic Giant Cell Carcinoma, and Sarcomatoid Carcinoma: An Analysis of 19 Cases

Aims We evaluated the molecular underpinnings of rare aggressive prostate cancer variants adenosquamous, pleomorphic giant cell, and sarcomatoid carcinomas. Methods and Results We retrieved 19 tumors with one or more variant(s) and performed ERG immunohistochemistry, a next‐generation sequencing assay targeting recurrent gene fusions, and fluorescence in situ hybridization (FISH) for ERG and BRAF. Divergent differentiation included: sarcomatoid (n=10), adenosquamous (n=7), and pleomorphic giant cell carcinoma (n=7). Five patients had more than one variant. Four had variants only in metastases. ERG rearrangement was detected in 9 (47%, 7 via sequencing, showing TMPRSS2‐ERG and one GRHL2‐ERG fusion, and 2 via FISH, showing rearrangement via deletion). Of these, ERG immunohistochemistry was positive in the adenocarcinoma for 8/9 (89%) but only 5/9 (56%, typically decreased) in the variant. One patient had false‐positive ERG immunohistochemistry in the sarcomatoid component despite negative FISH. Two (11%) harbored BRAF fusions (FAM131A‐BRAF and SND1‐BRAF). Conclusions ERG gene fusions are present in these rare prostate cancer variants with a close frequency to conventional prostate cancer (9/19, 47%). ERG immunohistochemistry usually detects rearrangement in the adenocarcinoma but is less sensitive for the variant histology with weak to negative staining. Adenosquamous and sarcomatoid variants particularly can occur together. Molecular assessment may be an additional tool in select cases to confirm prostatic origin of unusual tumors. The presence of 2 BRAF gene rearrangements suggests that this gene fusion may be enriched in this setting, as RAF kinase fusions have been previously reported in 1‐2% of prostate cancers

Diagnostic criteria for oncocytic renal neoplasms:a survey of urologic pathologists

Renal oncocytoma and chromophobe renal cell carcinoma (RCC) have been long recognized as distinct tumors; however, it remains unknown if uniform diagnostic criteria are used to distinguish these tumor types in practice. A survey was distributed to urologic pathologists regarding oncocytic tumors. Responses were received from 17/26 invitees. Histologically, >1 mitotic figure was regarded as most worrisome (n=10) or incompatible (n=6) with oncocytoma diagnosis. Interpretation of focal nuclear wrinkling, focal perinuclear clearing, and multinucleation depended on extent and did not necessarily exclude oncocytoma if minor. Staining techniques most commonly used included: CK7 (94%), KIT (71%), vimentin (65%), colloidal iron (59%), CD10 (53%), and AMACR (41%). Rare CK7-positive cells (≤5%) was regarded as most supportive of oncocytoma, although an extent excluding oncocytoma was not universal. Multiple chromosomal losses were most strongly supportive for chromophobe RCC diagnosis (65%). Less certainty was reported for chromosomal gain or a single loss. For tumors with mixed or inconclusive features, many participants use an intermediate diagnostic category (82%) that does not label the tumor as unequivocally benign or malignant, typically "oncocytic neoplasm" or "tumor" with comment. The term "hybrid tumor" was used variably in several scenarios. A slight majority (65%) report outright diagnosis of oncocytoma in needle biopsies. The morphologic, immunohistochemical, and genetic characteristics that define oncocytic renal tumors remain incompletely understood. Further studies correlating genetics, behavior, and histology are needed to define which tumors truly warrant classification as carcinomas for patient counseling and follow-up strategies

Reappraisal of Morphological Differences between Renal Medullary Carcinoma, Collecting Duct Carcinoma, and Fumarate Hydratase-Deficient Renal Cell Carcinoma

Renal medullary carcinomas (RMCs) and collecting duct carcinomas (CDCs) are rare subsets of lethal high-stage, high-grade distal nephron-related adenocarcinomas with a predilection for the renal medullary region. Recent findings have established an emerging group of fumarate hydratase (FH)-deficient tumors related to hereditary leiomyomatosis and renal cell carcinoma (HLRCC-RCCs) syndrome within this morphologic spectrum. Recently developed, reliable ancillary testing has enabled consistent separation between these tumor types. Here, we present the clinicopathologic features and differences in the morphologic patterns between RMC, CDC, and FH-deficient RCC in consequence of these recent developments. This study included a total of 100 cases classified using contemporary criteria and ancillary tests. Thirty-three RMCs (SMARCB1/INI1-deficient, hemoglobinopathy), 38 CDCs (SMARCB1/INI1-retained), and 29 RCCs defined by the FH-deficient phenotype (FH/2SC or FH/2SC with FH mutation, regardless of HLRCC syndromic stigmata/history) were selected. The spectrum of morphologic patterns was critically evaluated, and the differences between the morphologic patterns present in the 3 groups were analyzed statistically. Twenty-five percent of cases initially diagnosed as CDC were reclassified as FH-deficient RCC on the basis of our contemporary diagnostic approach. Among the different overlapping morphologic patterns, sieve-like/cribriform and reticular/yolk sac tumor-like patterns favored RMCs, whereas intracystic papillary and tubulocystic patterns favored FH-deficient RCC. The tubulopapillary pattern favored both CDCs and FH-deficient RCCs, and the multinodular infiltrating papillary pattern favored CDCs. Infiltrating glandular and solid sheets/cords/nested patterns were not statistically different among the 3 groups. Viral inclusion-like macronucleoli, considered as a hallmark of HLRCC-RCCs, were observed significantly more frequently in FH-deficient RCCs. Despite the overlapping morphology found among these clinically aggressive infiltrating high-grade adenocarcinomas of the kidney, reproducible differences in morphology emerged between these categories after rigorous characterization. Finally, we recommend that definitive diagnosis of CDC should only be made if RMC and FH-deficient RCC are excluded

Reporting trends, practices, and resource utilization in neuroendocrine tumors of the prostate gland: a survey among thirty-nine genitourinary pathologists

Background: Neuroendocrine differentiation in the prostate gland ranges from clinically insignificant neuroendocrine differentiation detected with markers in an otherwise conventional prostatic adenocarcinoma to a lethal high-grade small/large cell neuroendocrine carcinoma. The concept of neuroendocrine differentiation in prostatic adenocarcinoma has gained considerable importance due to its prognostic and therapeutic ramifications and pathologists play a pivotal role in its recognition. However, its awareness, reporting, and resource utilization practice patterns among pathologists are largely unknown. Methods: Representative examples of different spectrums of neuroendocrine differentiation along with a detailed questionnaire were shared among 39 urologic pathologists using the survey monkey software. Participants were specifically questioned about the use and awareness of the 2016 WHO classification of neuroendocrine tumors of the prostate, understanding of the clinical significance of each entity, and use of different immunohistochemical (IHC) markers. De-identified respondent data were analyzed. Results: A vast majority (90%) of the participants utilize IHC markers to confirm the diagnosis of small cell neuroendocrine carcinoma. A majority (87%) of the respondents were in agreement regarding the utilization of type of IHC markers for small cell neuroendocrine carcinoma for which 85% of the pathologists agreed that determination of the site of origin of a high-grade neuroendocrine carcinoma is not critical, as these are treated similarly. In the setting of mixed carcinomas, 62% of respondents indicated that they provide quantification and grading of the acinar component. There were varied responses regarding the prognostic implication of focal neuroendocrine cells in an otherwise conventional acinar adenocarcinoma and for Paneth cell-like differentiation. The classification of large cell neuroendocrine carcinoma was highly varied, with only 38% agreement in the illustrated case. Finally, despite the recommendation not to perform neuroendocrine markers in the absence of morphologic evidence of neuroendocrine differentiation, 62% would routinely utilize IHC in the work-up of a Gleason score 5 + 5 = 10 acinar adenocarcinoma and its differentiation from high-grade neuroendocrine carcinoma. Conclusion: There is a disparity in the practice utilization patterns among the urologic pathologists with regard to diagnosing high-grade neuroendocrine carcinoma and in understanding the clinical significance of focal neuroendocrine cells in an otherwise conventional acinar adenocarcinoma and Paneth cell-like neuroendocrine differentiation. There seems to have a trend towards overutilization of IHC to determine neuroendocrine differentiation in the absence of neuroendocrine features on morphology. The survey results suggest a need for further refinement and development of standardized guidelines for the classification and reporting of neuroendocrine differentiation in the prostate gland