Critical appraisal:Strom T, Caudell JJ, Han D, Zager JS, Yu D, Cruse CW, et al 2014

Critical Appraisal

Article being appraised

Strom T, Caudell JJ, Han D, Zager JS, Yu D, Cruse CW, et al. Radiotherapy influences local control in patients with desmoplastic melanoma. Cancer 2014 May 1;120(9):1369-78 Available from: http://www.ncbi.nlm.nih.gov/pubmed/24142775.

Applicable clinical question

What is the optimal management for primary desmoplastic neurotropic melanomas?

Key Facts

Study Design

cohort study

Study aims:

To analyse the impact of adjuvant postoperative RT on local and/or loco-regional recurrence rates.

Number of Patients:

277

Patients who were treated for nonmetastatic desmoplastic melanoma by surgery (wide excision with or without sentinel lymph node biopsy) with or without adjuvant RT were reviewed

164 in the No Radiotherapy group; 113 in the RT postoperative group

Reported outcome(s):

Local control (including local recurrence)
Loco-regional control

Results of outcome(s):

Local control:
- Adjuvant RT was associated with improved local control using log-rank analysis (P=.02) and Cox multivariable analysis (HR, 0.15; 95% CI, 0.06-0.39 [P<.001]).
- 28 of 164 patients (17%) who did not receive RT developed a local recurrence, compared with only 8 of 113 patients (7%) who received postoperative RT.
- 1-year and 5-year actuarial local control rates were 96% and 95%, respectively, for patients treated with adjuvant RT versus 91% and 76%, respectively, for unirradiated patients (log-rank P=.015)
- Among 35 patients with positive resection margins, 3 of 22 patients (14%) who received RT developed a local recurrence compared with 7 of 13 (54%) of those who did not (P=.003).
- The benefit of RT in patients with negative resection margins was not as pronounced; 5 of 89 radiated patients (6%) failed locally versus 19 of 148 unirradiated patients (13%) (P=.09)

Locoregional control:
- Patients treated with RT have significantly improved locoregional control on univariable (P=.02) and multivariable (HR, 0.20; 95% CI, 0.10- 0.40) (P<.001) analysis.
- 40 of 164 patients (24%) who did not receive local/regional RT developed a locoregional failure vs. 15 of 113 patients (13%) who did.
- Of 6 patients who received adjuvant locoregional RT for positive lymph nodes, 1 (17%) developed a regional recurrence, vs. 2 of 27 (7%) with positive lymph nodes who did not receive regional RT.
- Regional lymph node RT significantly associated with positive resection margins (OR, 7.0; 95%CI, 1.4-36.2 [P=.02]).
- Patients with positive resection margins: 23% had a locoregional recurrence with RT vs. 69% without (log-rank P=.002).
- Patients with negative resection margins: 10% experienced locoregional recurrence with RT versus 20% without (P=.06).

Includes an economic evaluation

no