The efficacy of adjuvant radiotherapy in dermatofibrosarcoma protuberans: a systemic review and meta-analysis

Dermatofibrosarcoma protuberans (DFSP) is a rare and locally aggressive tumour, with a high recurrence rate, even after complete surgical excision. Adjuvant radiotherapy (RT) has been suggested to reduce the risk of local recurrence after inadequate surgical resection in patients with narrow or positive surgical margins. However, the overall efficacy of adjuvant RT has not been well studied because of the rarity of DFSP and lack of an appropriate comparison group.

We sought to evaluate the efficacy of adjuvant RT for DFSP by conducting a systemic review and meta-analysis to provide a more evidence-based measure of its effectiveness.

We conducted a systemic review of articles published before 31 June 2015. Due to the rarity of the disease, we included all studies that reported DFSP patients who received adjuvant RT (postoperatively). The pooled recurrence rates were analysed from these extracted data.

Twelve studies met the inclusion criteria. The pooled estimate of the recurrence rate for all adjuvant radiotherapy was 11.74% (95% CI 7.4-17.38; n = 167). Patients with positive/close had a pooled recurrence rate of 14.23% (95% CI 8.13-22.49; n = 92), whereas there was no recurrence in patients with negative margins. The pooled estimate of the recurrence rate between surgery alone and surgery combined with adjuvant radiotherapy showed no significant difference (odds ratio 0.31, P = 0.07), although there was a trend that adjuvant RT had a lower recurrence rate than surgery alone.

Adjuvant RT might be considered for all patients undergoing surgical excision, even if a negative surgical margin has been achieved. Furthermore, for patients with large or recurrent tumours, especially when wide excision with negative margin would result in a significant functional or cosmetic deficit, postoperative radiotherapy is highly recommended in order to achieve a lower recurrence rate.