1494P - Dermatofibrosarcoma Protuberans might not benefit from Postoperative Radiotherapy after Local Resection with Negative Margin

Date 11 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Soft Tissue Sarcomas
Sarcoma
Surgery and/or Radiotherapy of Cancer
Presenter Juhui Chen
Citation Annals of Oncology (2017) 28 (suppl_5): v521-v538. 10.1093/annonc/mdx387
Authors J. Chen, K.X. Du, J.Y. He, Q.Q. Peng, L.R. Tan, J.L. Li, K.X. Du
  • Department Of Radiation Oncology, Fujian Provincial Cancer Hospital, 350014 - Fuzhou/CN

Abstract

Background

To evaluate the role of postoperative radiotherapy (RT) in the treatment of dermatofibrosarcoma protuberans (DFSP) after local resection with negative margin.

Methods

We retrospectively analyzed 84 consecutively treated DFSP patients who received local resection (≤2cm) with negative margin from 2000 to 2016 in our institution. Statistical analysis was performed with a commercially available statistical software package.

Results

The median follow-up was 60 months (range, 10-201). For patients (28/84) with postoperative RT, four (4/28) patients were found to had local relapse, while three of them had ≤ 1 cm surgical margin. For patients without postoperative RT, four (4/56) patients had local failure. Postoperative RT failed to improve the local recurrence-free survival (LRFS) of DFSP after local resection with negative margin (Fisher=0.431). Patients with fibrosarcomatous DFSP (FS-DFSP) were found to have higher local recurrent rate than DFSP (66.7% vs. 7.4%, Fisher=0.023). Twenty-six patients were examined for ki-67, and positive range is 1-30%. Patients with high ki-67 expression (>15%) were found to have higher local recurrence rate than the others (80.0%vs0%, Fisher=0.000).

Conclusions

Postoperative RT did not improve the LRFS of DFSP after local resection with negative margin. FS-DFSP was more likely to have a local relapse than the other types. Ki-67 might become a good predictor for local control of DFSP.

Clinical trial identification

Legal entity responsible for the study

Kai xin Kaixin Du

Funding

None

Disclosure

All authors have declared no conflicts of interest.