International Journal of Surgical Pathology

The paratestis (PT) is defined by the testicular tunics, epididymis, spermatic cord, rete testis, and embryonic remnants. It gives rise to a large diversity of pathologies, including those of soft tissue, which may prompt orchiectomy. We performed a 17-year search of our database for orchiectomies for a PT soft-tissue mass. In a total of 4741 orchiectomy specimens, 138 orchiectomies were performed for primary neoplastic or nonneoplastic masses of the PT soft tissue or had an incidental PT soft-tissue mass. Of these, 65.9% were neoplastic. The mean age was 40.2 years (range: <1 to 87 years) and was similar for neoplastic and nonneoplastic lesions. The most common malignancies were rhabdomyosarcoma (31/63 malignancies), liposarcoma (19/63), and leiomyosarcoma (5/63), with the former occurring in younger patients (average: 18.3 years). No malignancies were incidental. The most common benign neoplasm was spermatic cord lipoma (24/28 of benign neoplasms); however, most were incidental. This was followed by leiomyoma (3/28) and hemangioma (1/28). The most common nonneoplastic lesions were adrenal rests (22/47 nonneoplastic cases); however, all were incidental findings. Of 47 nonneoplastic masses, 22 prompted orchiectomy, and of these, the most common diagnosis was fibrous/nodular periorchitis (11/47). Of 88 nonincidental lesions, 25 were either benign neoplasms (3/25) or nonneoplastic (22/25). These data indicate that PT soft-tissue neoplasms prompting orchiectomy are disproportionately rhabdomyosarcomas, though these are principally in young patients. In older patients, malignancies are more frequently liposarcomas. However, almost one-third of orchiectomies performed for PT soft-tissue masses yield benign lesions, indicating an opportunity to reduce unnecessary procedures.

Background. Renal anastomosing hemangioma (RAH) is a very rare distinct entity composed of anastomosing sinusoidal (spleen-like) capillary-sized vessels lined by flat or hobnail endothelial cells. Most of the published cases of RAH occurred in the setting of end-stage renal disease (ESRD). Methods. We present 2 cases of RAH in ESRD along with a literature review. We compared clinicopathologic features of RAHs in end-stage and non–end-stage kidneys. A meta-analysis was conducted with PubMed and a manual search through references of relevant publications. Individual patient data gathered from the literature were used in the analysis. Results. Our systematic review revealed 49 RAHs, including our 2 cases. Thirty-two (65.3%) cases were in ESRD, only 17 (34.7%) were in patients with non-ESRD. RAHs in ESRD were in younger patients, smaller in size, multifocal, and seen more with renal epithelial neoplasms when compared with RAHs in non-ESRD (P < .05). Extramedullary hematopoiesis was seen mostly in RAHs in ESRD kidneys (85% vs 41.7%) (P = .018). Follow-up data were available for 25 cases with a mean follow-up of 24.58 ± 38.54 months. Recurrence, metastasis, or death have never been described related to RAH in any patients. Conclusions. In conclusion, RAHs are rare and mostly arise in kidneys with end-stage damage. RAHs in ESRD and non-ESRD differ in terms of clinicopathologic features.

Background. Protein kinase C βII promotes melanogenesis and affects proliferation of melanocytic cells but is frequently absent or decreased in melanoma cells in vitro. Objective. To investigate PKC-βII expression and spatial distribution within a lesion in various benign and malignant melanocytic proliferations. Methods. Expression of PKC-βII was semiquantitatively assessed in the various existing compartments (intraepidermal [not nested], junctional [nested], and dermal) of benign (n = 43) and malignant (n = 28) melanocytic lesions by immunohistochemistry. Results. Melanocytes in the basal layer of normal skin or in lentigo simplex stained strongly for PKC-βII. Common nevi lacked completely PKC-βII. All other lesions expressed variably PKC-βII, with cutaneous melanoma metastases displaying the lowest rate of positivity (14%). In the topographical analysis within a lesion, PKC-βII expression was largely retained in the intraepidermal and junctional part of all other lesions (dysplastic nevus, lentigo maligna, and melanoma). Reduced expression of PKC-βII was found in the dermal component of benign and malignant lesions (P = .041 vs intraepidermal). PKC-βII expression in the various compartments did not differ significantly between benign and malignant lesions. Conclusions. The current study revealed a significant correlation between PKC-βII expression and spatial localization of melanocytes, with the lowest expression found in the dermal compartment and the highest in the epidermal compartment.

Anaplastic large cell lymphoma (ALCL) is a T-cell lymphoma which has been recognized to have a variable clinical presentation and a broad spectrum of histomorphologic features. Its variable histomorphologic appearances are sometimes diagnostically challenging for the pathologists since they can mimic sarcomas, melanomas and undifferentiated carcinomas. To our knowledge, a previous case of axillary soft-tissue mass of ALK-positive ALCL with an alveolar growth pattern has been so far reported in the literature. This alveolar appearance is unusual for ALCL. It can impose a diagnostic pitfall, particularly in extranodal soft-tissue masses. We report a case of ALK-negative ALCL that presented as an extranodal soft-tissue neck mass in an adult man. Histologically, it showed a characteristic alveolar growth pattern composed of well-defined nests of dyscohesive highly pleomorphic large neoplastic cells separated by thin fibrovascular septae. Morphologically, it mimicked sarcomas, carcinomas, melanoma and germ cell neoplasms. Initially, a histologic diagnosis of ALCL was not considered. However, the negative immunomarkers for the above mimickers and the strong CD30 positivity have raised the suspicion of anaplastic lymphomas. Further immunohistochemistry studies showed the neoplastic cells to be positive for CD4 and CD43. This case report emphasizes the potential diagnostic pitfalls associated with an ALK-negative ALCL when manifests as a soft-tissue mass with an alveolar growth pattern. Pathologists should be aware of this uncommon growth pattern in ALCLs. They should implement a broad panel of immunomarkers in soft-tissue masses of anaplastic pleomorphic cells with an alveolar morphology.

A patient with postmenopausal bleeding and virilization was found to have bilaterally enlarged ovaries with a yellow cut surface. Histology revealed cortical stromal hyperplasia with stromal hyperthecosis. This hyperplastic condition should not be mistaken for an ovarian neoplasm.

Primary pulmonary myxoid sarcoma (PPMS) is a recently described, exceedingly rare low-grade lung sarcoma that tends to present in young females as an endobronchial mass and shows evidence of an EWSR1-CREB1 fusion. Herein, we present a case of PPMS with fluorescence in situ hybridization (FISH) analysis for EWSR1 and CREB1 rearrangements. An 80-year-old woman presented with an endobronchial, multinodular tumor exhibiting spindle, ovoid and epithelioid cells arranged in reticular/lattice-like and alveolar-like patterns in a myxoid background. The tumor showed focal epithelial membrane antigen immunoreactivity as well as an Alcian blue–positive stroma that was sensitive to digestion with hyaluronidase. EWSR1 and CREB1 rearrangements were detected by break-apart FISH probes. The patient showed persistence of disease 36 months after diagnosis and was discharged to hospice care. We contribute with a report of an additional case of this very unusual entity and perform a brief review of the literature published so far on the subject.

Ossifying fibromyxoid tumor (OFMT) is a mesenchymal neoplasm of uncertain lineage and intermediate biologic behavior. Involvement of the head and neck area is infrequent (10% to 15%) and intraoral presentation is very rare. An OFMT developing in the retromolar trigone of a 13-year-old male is presented, along with a comprehensive review of oral OFMT cases. Among 12 oral OFMTs (including the present case), most patients were male (72.7%), with a mean age of 30.3 (13-67) years. The tumors generally appeared as painless masses of firm or hard consistency (mean diameter 27.7 mm), most commonly located in the soft tissues of the mandible (50%). Common microscopic features included ossification, lack of atypia or high mitotic activity, and immunohistochemical positivity for S100 (5/7), vimentin (6/6), GFAP (3/6), and SMA (2/6). Recurrence was reported only in one case. Further characterization of this rare entity is needed to increase our understanding of its distinct clinical and histopathologic features.

Extensive extracellular mucin deposition is a rare pathological thyroid condition with 6 cases described in literature so far. We report another case of a 67-year-old woman, discussing histopathological features, and review the literature. Our findings showed a diffuse mucin deposition in the stromal compartment of thyroid parenchyma. Histochemical stainings showed positivity for Alcian blue staining, but not for periodic acid–Shiff staining. Our case is peculiar because this mucin deposition was associated with benign nodular hyperplasia, in contrast with the other 6 reports, which described the same stromal alterations associated with benign or malignant thyroid tumors.

Juvenile papillomatosis of the breast (JPB, also known as Swiss cheese disease) is a rare ailment that typically afflicts young females, and presents as a mass-forming lesion. The lesional mass usually comprises multiple cysts and duct stasis, amid a variety of proliferative and nonproliferative epithelial changes. The proliferative changes include papillary hyperplasia, florid hyperplasia, and papillary apocrine hyperplasia. Concurrent carcinoma (either in situ or invasive) is present in approximately 10% of cases at presentation, and subsequent carcinoma (either in situ or invasive) is diagnosed in about 10% of patients. About 20% of patients have a strong family history of breast carcinoma. A total of 10 cases of JPB have been previously reported in males, both children and adults, only one of which, in a 33-year-old, was associated with invasive carcinoma. Here, another case of JPB in a 45-year-old male—one with subsequent sequential diagnoses of ipsilateral intraductal carcinoma, invasive carcinoma, and widely metastatic carcinoma over the course of 15 years—is reported.

Perivascular epithelioid cell tumors (PEComas) are infrequent neoplasms with peculiar myomelanocytic differentiation. The aggressive abdominopelvic variant is rare, with only a small number of published cases. We present an additional case of this unusual variant, which showed an aggressive histologic and clinical behavior with multiple liver metastases and resistance to several therapies. We also discuss the histological and immunohistochemical profiles as well as the differential diagnosis.

We report a case of colonic adenosquamous carcinoma with MSI-H (microsatellite instability–high) in a 43-year-old male who presented with bowel obstruction due to a circumferential mass involving the descending colon and splenic flexure. Microscopically, it showed poorly differentiated adenocarcinoma with squamous differentiation, tumor infiltrating lymphocytes >3/high-power field, and mild peritumoral lymphocytic response. Immunohistochemistry was equivocal for MLH-1, PMS-2, and MSH-2, with retention of MSH-6 expression. Polymerase chain reaction testing demonstrated MSI-H pattern with instability of BAT-25, BAT-26, and NR-21. Review of the literature revealed only one recently published case of MSI-H adenosquamous carcinoma. The role of MSI in adenosquamous carcinoma pathogenesis is still unknown. In conclusion, MSI testing in colonic adenosquamous carcinoma combined with other MSI-related clinical and histological features is indicated.

Sertoliform cystadenoma is a rare benign tumor of the rete testis with 8 previously reported cases and an additional 14 cases reported in an abstract form. It usually presents with a unilateral scrotal mass, clinically and radiologically indistinguishable from malignant testicular tumors. We report a 39-year-old man who presented with a right testicular mass. The patient underwent radical inguinal orchiectomy. Grossly, no masses were appreciated. After histologic examination with subsequent immunohistochemical staining, a sertoliform cystadenoma of the rete testis was diagnosed.

Spermatocytic tumor, formerly known as spermatocytic seminoma, is an uncommon testicular neoplasm which is a distinct clinicopathologic entity from classic seminoma. These tumors are not associated with germ cell neoplasia in situ, other germ cell tumors, or isochromosome 12p. Although typically, these tumors have an excellent prognosis occasional cases are associated with sarcoma and have a very poor prognosis. We present a case of spermatocytic tumor with sarcoma showing a chondrosarcomatous component, discuss the pathologic findings and differential diagnosis and provide follow-up information.

Only 28 cases of pseudomyxoma peritonei (PMP) arising from urachal neoplasms have been reported. We report one example of this extremely rare disease with KRAS mutational status in its spectrum of pathology. A 45-year-old woman presented with urachal frankly invasive mucinous cystadenocarcinoma confined to the dome of the bladder, which clinically manifested as PMP and was not detected at the first surgery. The primary tumour was revealed 6 months later because of its recurrence as PMP. Microscopic investigation revealed tubular adenoma and cystadenocarcinoma communicating with the bladder lumen and transitioning from the urachal urothelium to the mucinous epithelium. A urachal remnant was identified near the neoplasm. On immunohistochemistry, the tumour proved positive for CK7, CK20, CEA, and CDX2. Staining for β-catenin revealed expression in both the cytoplasm and cell membrane. Mismatch repair protein expression was normal. Somatic KRAS-mutation (G12V) was revealed in tubular adenoma, cystadenocarcinoma, and mucinous carcinoma peritonei and may play an oncogenic role in the malignant transformation of urachal mucosa and the development of PMP.

We describe an atypical teratoid rhabdoid tumor (AT/RT) with a component of low-grade and anaplastic rhabdoid meningioma in a 7-year-old child. The AT/RT was uniformly negative for INI1 and displayed immunoreactivity for vimentin, P53, CD99, cytokeratins with AE1/AE3 antibodies, epithelial membrane antigen, β-catenin, smooth muscle actin, E-cadherin, and S-100 protein. AT/RT was continuous, with small foci of recognizable low-grade and anaplastic meningioma. The low-grade meningioma was INI1 positive with scattered INI1-negative nuclei, whereas the remaining tumor components were INI1 negative. A recurrent tumor 6 months after partial resection contained only INI1-negative AT/RT. This case supports the hypothesis that rare examples of AT/RT may emerge from a preexisting “parent” neoplasm as a result of a second hit mutation.