Primary pleural epithelioid sarcoma of the proximal type: a diagnostic and therapeutic challenge

Abstract

Epithelioid sarcoma (ES) is an uncommon soft tissue neoplasm first described in 1970. It is a unique soft tissue neoplasm of adolescents and younger adults which usually presents as a subcutaneous and deep dermal mass in the distal portions of the extremities. The proximal-type variant of this rare soft tissue neoplasm was only recently reported. The proximal form typically arise in proximal extremities and in the deep parts of pelvis, perineum and genital tract. The proximal type variant has distinct histological characteristics and aggressive clinical course as compared to the distal ES. Inactivation of INI1 has been reported in both distal and proximal variants and can help to make the diagnosis. Furthermore, the proximal variant has a possible association with malignant rhabdoid neoplasm. We describe here a case of primary pleural ES of the proximal type and highlight its diagnostic and therapeutic challenges.

Molecular and immunophenotypic characterization of SMARCB1 (INI1) - deficient intrathoracic Neoplasms

“…MRT of the mediastinum is a rare aggressive tumor, with less than 30 cases reported in adults 25 . The same accounts for proximal type epithelioid sarcoma in the mediastinum with even fever reported cases [26][27][28] . For a better differentiation of these two entities, molecular work-ups might be helpful.…”

SMARCB1/INI1-deficient tumors of adulthood

“…We located 25 cases of adult SMARCB1/INI1-deficient sarcomas that were described in 18 reports ( Table 3 ) 42 , 50 , 93 – 108 . Median age at the time of diagnosis was 36 years old.…”