Dermatofibrosarcoma Protuberans Treatment in South Dakota.

Introduction: Dermatofibrosarcoma protuberans (DFSP) is a rare, locally aggressive dermal soft tissue sarcoma. Local recurrences, reported at rates between 2-19%, risk sarcomatous transformation and increasing risk for metastasis. Swift diagnosis and appropriate management mitigate the risk of advanced local disease, extensive surgical resection, and subsequent risk of metastasis. Clinically, DFSP resembles multiple, common subcutaneous growths. Misdiagnosis leads to incorrect or delayed treatment. This study investigates whether access to dermatology affects outcomes of DFSP treatment in South Dakota by characterizing the rates of appropriate workup, diagnosis, treatment, and recurrence rates among dermatology and non-dermatology providers.

Methods: This study was a retrospective review for 24 adults with a histological DFSP diagnosis. The study evaluated three endpoints: rates of appropriate workup and diagnosis comparing dermatology and non-dermatology providers, rates of appropriate primary treatment between lesions with and without appropriate workup and diagnosis, and rates of positive margins or primary recurrence between lesions with and without appropriate primary treatment.

Results: The results for the first endpoint were not statistically significant (OR = 0.13, 95% CI: 0.012 - 1.33, p = 0.0774). The data rejected the null hypothesis of the second and third endpoints, (OR = 0.065, 95% CI: 0.0062 - 0.674, p = 0.0272), respectively. Clinical tumor size did not independently impact the treatment course for DFSP (OR: 0.43, 95% CI: 0.066 - 2.80, p = 0.657). Finally, there were no metastases in any of the 24 patients.

Conclusion: Patient outcomes are better when providers biopsy DFSPs on initial presentation. Without a biopsy and uncertain diagnosis prior to treatment, providers excise insufficient surgical margins. This increases overall morbidity before achieving clear surgical margins. Higher clinical suspicion for DFSP prompting appropriate biopsy prior to surgical treatment should improve patient outcomes.