Clear cell variant of atypical fibroxanthoma and pleomorphic dermal sarcoma: Molecular characterization and review of the literature

Abstract

Atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS) are unusual cutaneous tumors that typically arise in sun-damaged skin of elderly individuals.Several histopathologic variants have been described, but the clear cell variant is particularly rare with only 18 cases of AFX and one case of PDS reported. Here, we present two cases of clear cell AFX and PDS highlighting key histopathologic findings and molecular alterations assessed by next-generation sequencing.

In vivo reflectance confocal microscopy findings in a case of atypical fibroxanthoma

“…To the best of our knowledge, only one previous publication 6 described the RCM features of AFX, the clear cell variant, which is a rarely reported histologic subtype composed of epithelioid or spindle‐shaped cells with clear or vacuolated cytoplasm. The tumoral cells were described as irregularly shaped hyperreflective small cells on RCM.…”

Clear Cell Pleomorphic Dermal Sarcoma: A Case Report and Literature Review

“…Several histologic variants have been identified, such as spindle cell, keloidal, granular cell, clear cell (CC), osteoclast-like giant cell, pigmented hemosiderotic, pseudoangiomatous, and myxoid variants [5]. Among them, the CC variant is particularly rare with only two cases of PDS reported in the literature to date [4]. Here, we present a case of CC-PDS highlighting key histopathologic findings and differential diagnosis with a review of the English literature.…”

“…Therefore, it is clinically important to distinguish between these tumors based on histopathologic features. PDS can be differentiated from AFX by the larger size (>2 cm), and the presence of adverse histopathologic features such as invasion of the subcutaneous tissue, tumor necrosis, and lymphovascular and/or perineural invasion [2] [3] [4]. Several histologic variants have been identified, such as spindle cell, keloidal, granular cell, clear cell (CC), osteoclast-like giant cell, pigmented hemosiderotic, pseudoangiomatous, and myxoid variants [5].…”

“…CC-AFX/PDS is a rare variant with a wide range of histopathological differential diagnosis. To our knowledge, only two CC-PDS cases have been reported in the English literature[4].…”