Immunohistochemical evidence for mesothelial origin of paratesticular adenomatoid tumour

Vacuolated cell pattern of pancreatobiliary adenocarcinoma: a clinicopathological analysis of 24 cases of a poorly recognized distinctive morphologic variant important in the differential diagnosis

Pancreatic ductal adenocarcinoma (PDCA) is characterized by well-defined tubular units in the vast majority of the cases; however, variations in this theme do occur. It is important to recognize the morphologic spectrum of PDCA to avoid misdiagnosis especially in small specimens and also in metastatic foci. Here, we document a morphologic variant of PDCA that is characterized by a distinctive pattern of infiltrating cribriform nests in a distinctive "microcystic" or "secretory" pattern. Twenty-four cases of PDCA have been identified in a review of 505 cases diagnosed with PDCA. Histologically, this pattern was characterized by infiltrating nests of tumor cells with large vacuoles and "signet-ring" like appearance imparting a cribriform growth pattern. The vacuoles were one to five cells in size, often merging to form multilocular spaces separated by a thin rim of cell membrane. Many of these spaces contained CA19.9 positive granular secretory material. The nuclei were often pushed to the periphery and compressed in a pattern resembling adipocytes, although the nuclei were often densely hyperchromatic and displayed significant atypia. Especially in biopsies from the peripancreatic fat and peritoneum, these neoplastic cells had been misdiagnosed as degenerating adipocytes, and in the lymph nodes, they had been misinterpreted as lipogranulomas. Clinical findings of the patients were similar to that of conventional PDCA, except higher incidence of history of smoking (83% vs. 60%; p=0.034). In conclusion, vacuolated cell adenocarcinoma is a distinct morphologic variant of PDCA, and the presence of this peculiar pattern in a metastatic site, although not specific, should raise the suspicion of a PDCA.

Adenomatoid tumor of epididymidis: A case report

Background

Adenomatoid tumors are regarded as distinctive benign mesothelial neoplasms of the paratesticular region, most commonly occuring at the tail of the epididymidis.

Because of its rarity, the clinical and histopathological aspects are discussed.

Case presentation

We present the case of a 41-year-old patient with an adenomatoid tumour located in the tail of the left epididymis that referred to our department with gradual enlarged intrascrotal mass. The diagnosis was achieved by echography, and was confirmed by surgical excision and histological analysis.

Conclusion

Due to its low incidence in intrascrotal pathology, we believe it is important for the physician to be aware of this interesting entity in order to make a differential diagnosis from other inflammatory processes and to adopt the proper surgical approach.

Selected other problematic testicular and paratesticular lesions: rete testis neoplasms and pseudotumors, mesothelial lesions and secondary tumors

The proximity and, in some instances, communication between several structures in the testis and paratestis (rete testis, epididymis, mesothelium, vestigial epithelium and paratesticular soft tissue) result in a plethora of interesting tumors and tumor-like lesions that together pose a formidable diagnostic challenge both because of their morphologic overlap and rarity. The occasional spread of tumors primarily at other sites to this region adds to the potential problem encountered. This review provides an overview of the pathology of nonmesenchymal paratesticular neoplasms and pseudotumors with a focus on the approach to tubulopapillary neoplasms for which diagnostic considerations may include carcinoma of the rete testis, malignant mesothelioma, ovarian-type epithelial tumors, epididymal carcinoma and metastatic carcinomas. The cornerstone of accurate characterization of these lesions is still a comprehensive, traditional clinicopathologic approach, clinical history (of another primary), gross examination (location) and routine light microscopy, but judicious incorporation of contemporary immunohistochemical markers may aid or in some instances be crucial in resolving the problems encountered.