title: Dermatofibrosarcoma protuberans (DFSP): predictors of recurrence and the use of systemic therapy.
abstract: BACKGROUND
  Dermatofibrosarcoma protuberans (DFSP) is an uncommon soft tissue malignancy that typically presents with local invasion but rarely metastasizes. We examine clinicopathologic factors associated with disease-free survival (DFS) in patients with primary and recurrent DFSP and evaluate responses to multimodality therapy.
  
  
  METHODS
  Patients treated for DFSP were identified in a prospectively maintained database. Clinicopathologic factors associated with DFS were analyzed using univariate and multivariate analysis.
  
  
  RESULTS
  A total of 244 patients with DFSP were identified. Median follow-up was 50 months. A total of 14 patients had local recurrence (LR), and 2 patients had distant recurrence (DR), with a median time to recurrence of 35 months. At time of last follow-up, 70% and 47% of patients showed no evidence of disease (NED) in the primary (n = 197) and recurrent groups (n = 47), respectively. On univariate analysis, tumor location and depth were associated with DFS in the primary group, while margin status (R1 vs. R0) was associated with DFS in the LR group. On multivariate analysis, only depth (primary group) and margin status (LR group), remained significant. Also, 22 patients had therapy other than surgical resection: 14 radiotherapy, 4 tyrosine kinase inhibitor (TKI) only, 2 conventional chemotherapy only, and 2 chemotherapy plus TKI. Responses to other therapies were variable.
  
  
  CONCLUSIONS
  DFS after treatment for DFSP is strongly predicted by tumor depth in the primary setting and margin status in recurrent tumors. The treatment for DFSP in the primary or recurrent setting is excision with negative margins, resulting in low recurrence rates and infrequent metastatic spread. Multimodality treatment, especially TKI use, can be effective, but is not curative.
authors.affiliation: Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY, USA. fieldsr@mskcc.org
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Fields
authors.forename: Meera
authors.initials: M
authors.lastname: Hameed
authors.forename: Li-Xuan
authors.initials: LX
authors.lastname: Qin
authors.forename: Nicole
authors.initials: N
authors.lastname: Moraco
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Jia
authors.forename: Robert G
authors.initials: RG
authors.lastname: Maki
authors.forename: Samuel
authors.initials: S
authors.lastname: Singer
authors.forename: Murray F
authors.initials: MF
authors.lastname: Brennan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D018223:Dermatofibrosarcoma / Q000473:pathology / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000628:therapy*; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult