Thoracic schwannoma mimicking a Darier-Ferrand dermatofibrosarcoma: Diagnostic and reconstructive challenges

Primitive schwannoma refers to a rare benign tumor that originates from Schwann cells, which surround and insulate peripheral nerve fibers. These tumors are benign, exhibit slow growth, and have a very low risk of malignant transformation. They can remain asymptomatic for years or cause pain, paresthesia, or neurological deficits. When they develop in atypical regions, such as soft tissues or subcutaneous areas, they may be mistaken for other types of tumor masses. This is the case in our study, which reports on a patient referred to us for a thoracic cutaneous tumor with a partial biopsy result suggesting a schwannoma. Treatment involved complete surgical excision. Histological analysis of the surgical specimen revealed a surprising finding: a dermatofibrosarcoma of Darrier and Ferrand (DFSP), often considered a differential diagnosis for schwannoma. This study highlights both the importance of intraoperative frozen section analysis during surgery and the crucial role of the plastic surgeon in managing extensive and deep tissue defects that were unexpected based on the initial clinical diagnosis.