Clinical Images  |   August 2020
Undifferentiated Pleomorphic Sarcoma
Author Notes
  • From Ohio University Heritage College of Osteopathic Medicine in Athens. 
  • Financial Disclosures: None reported. 
  • Support: None reported. 
  •  *Address correspondence to Matthew J. Ferry, OMS IV, 5550 Middle Falls St, Dublin, Ohio, 43016-6280. Email:
Article Information
Imaging / Clinical Images
Clinical Images   |   August 2020
Undifferentiated Pleomorphic Sarcoma
The Journal of the American Osteopathic Association, August 2020, Vol. 120, 543. doi:
The Journal of the American Osteopathic Association, August 2020, Vol. 120, 543. doi:
An 86-year-old man presented with an ulcerated plaque on the right antihelix that had been present for several months (image A). Superficial biopsy revealed an atypical spindle cell proliferation, consistent with an atypical fibroxanthoma (AFX). Mohs surgery was performed, and histopathologic analysis showed uniform atypical spindle cells in a storiform pattern filling the dermis to the subcutis, suggesting the diagnosis of an undifferentiated pleomorphic sarcoma (UPS) (image B). 
AFXs are uncommon cutaneous neoplasms of pleomorphic myofibroblast-like cells.1 Whether these lesions represent keratin-positive dermal sarcomas or poorly differentiated carcinomas is debatable. Diagnosis requires exclusion of other undifferentiated spindle and pleomorphic cell neoplasms, such as UPSs, by immunohistochemical analysis.2 These soft tissue tumors present with AFX-like clinical and pathologic findings, but have higher-grade histologic features with greater rates of local recurrence and metastasis.2 While evidence indicates that these neoplasms lie on the same clinicopathologic spectrum, diagnostic criteria separating the 2 remains ill-defined.2 Consequently, clinical experience suggests that such cases should be managed promptly and treated aggressively. Despite clear margins, the tumor recurred in the patient and, ultimately, metastasized. 
Mahalingam S, Shah A, Stewart A. Atypical fibroxanthoma: a case series and review of literature. Auris Nasus Larynx. 2015;42(6):469-471. doi: 10.1016/j.anl.2015.04.001 [CrossRef] [PubMed]
Soleymani T, Aasi SZ, Novoa R, Hollmig ST. Atypical fibroxanthoma and pleomorphic dermal sarcoma: updates on classification and management. Dermatol Clin. 2019;37(3):253-259. doi: 10.1016/j.det.2019.02.001 [CrossRef] [PubMed]