Low-grade endometrial stromal sarcoma-like tumors in male with JAZF1 gene fusions

Paratesticular Endometrial Stromal Sarcoma-Like Sarcoma With EPC1-SUZ12 Fusion

Endometrial stromal sarcoma-like (ESS-like) sarcomas have rarely been described in male patients and represent a subset of "Mullerian analog" tumors. These ESS-like sarcomas most commonly arise in the paratesticular or pelvic regions and often harbor the same signature molecular fusion events that are typical of endometrial stromal sarcoma (ESS) of the uterine corpus. Here we report and describe an ESS-like sarcoma of the paratesticular soft tissue in an 85-year-old man with an EPC1-SUZ12 t(10;17)(p11.22;q12) fusion. This fusion event has been described in a high-grade uterine ESS one time previously where it displayed an aggressive clinical course. However, our patient showed no evidence of metastatic disease prior to surgery or in a short follow-up period after resection.

Spindle Cell Sarcoma With Novel JAZF1::NUDT5 Gene Fusion: Report of a Previously Undescribed Neoplasm

Gene fusions involving JAZF1 are a recurrent event in low grade endometrial stromal sarcoma, and have been more recently described in few instances of endometrial stromal sarcoma-like tumors in the genitourinary tract of men. In this article, we describe a previously unreported spindle cell sarcoma harboring an in-frame JAZF1::NUDT5 gene fusion, arising in the chest wall of a 51-year-old man. The tumor had unique morphologic features resembling both endometrial stromal sarcoma and endometrial stromal sarcoma-like tumors, consisting of a mixture of cytologically bland and pleomorphic spindle cells with brisk mitotic activity, within an alternating myxoid and fibrous stroma. It had diffuse immunohistochemical expression of CD10, CD34 and CD56, and variable expression of androgen receptor. To our knowledge, neoplasms with these clinico-pathologic characteristics and novel gene fusion have not been previously reported in the English language literature.

Soft tissue sarcoma with ZC3H7B::BCOR fusion in a male mimicking low-grade fibromyxoid sarcoma - A case report

Diagnosis of soft tissue tumors is often challenging, given the large number of entities, often with non-specific or overlapping morphology. Although morphology still plays an important part in diagnostic process, additional studies including immunohistochemistry and molecular genetics are often needed to arrive at correct diagnosis. We report a case of 61-year-old male with subcutaneous tumor in right hip area, that was surgically removed. The tumor was composed of uniform bland spindle cells in mild to moderately cellular myxoid nodules, with limited areas of collagenization and the diagnosis of low grade fibromyxoid sarcoma was made. The tumor recurred 3 years after the initial diagnosis and the new sample showed a high-grade round cell sarcoma with limited residual low-grade areas and non-specific immunoprofile after extended immunohistochemical work-up. Molecular analysis demonstrated ZC3H7B::BCOR fusion. Sarcomas with ZC3H7B::BCOR fusion occurring outside of uterus are exceedingly rare. A comprehensive review of previously published cases and a short discussion about classification of the entity is provided, together with data about morphology and immunoprofile of the lesions. The case also underscores the necessity of extended work up of soft tissue tumors with unusual immunohistochemical or morphological features in order to accurately assess their biological potential.

High-grade endometrial stromal sarcoma-like' sarcoma in male: Does it exist? A case report and review of the literature

We report an exceptional case of an undifferentiated round and spindle cell sarcoma, occurring in the periprostatic region of a 54-year-old male, with a 'high-grade endometrial stromal sarcoma-like' (HG-ESS) morphology and harboring a ZC3H7B::BCOR gene fusion identified by RNA-based next-generation sequencing. In this report, we describe the striking overlap of morphologic, immunohistochemical and molecular features of this current case and previously reported similar cases with ZC3H7B::BCOR fusion-positive HG-ESS, and discuss the differential diagnosis and possible pathogenesis of this unusual entity.