Mechanisms of Local Aggressiveness Without Metastasis in Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma characterized by marked local invasiveness and a low but definite risk of metastasis. The biological basis for this discrepancy remains incompletely understood. This review synthesizes current evidence regarding local invasion, metastatic behavior, tumor microenvironment, vascular and lymphatic involvement, and the role of the collagen type I alpha 1 (COL1A1)-platelet-derived growth factor beta (PDGFB) fusion.

A narrative review of peer-reviewed literature was conducted, prioritizing PubMed-indexed studies published between 2010 and 2026, with inclusion of foundational studies where necessary. Emphasis was placed on clinicopathologic behavior, fibrosarcomatous transformation, stromal signaling, lymphovascular invasion, and molecular drivers.

DFSP demonstrates infiltrative growth into the dermis and subcutis, frequently extending beyond clinically apparent margins. The COL1A1-PDGFB fusion drives PDGFRβ signaling and tumorigenesis but does not independently confer metastatic potential. Metastasis is uncommon in conventional DFSP and occurs more frequently in fibrosarcomatous variants. Available evidence supports a model of stromal niche dependence, limited lymphovascular invasion, and incomplete acquisition of dissemination mechanisms.

DFSP appears biologically optimized for local stromal infiltration rather than systemic dissemination. Rare metastatic progression likely reflects the acquisition of additional molecular and microenvironmental features, particularly in fibrosarcomatous transformation. Further investigation into stromal interactions and vascular access mechanisms is warranted.