Radiotherapy for perineural invasion in cutaneous head and neck carcinomas: toward a risk-adapted treatment approach.

Abstract

We retrospectively reviewed outcomes in patients treated with radiotherapy (RT) for cutaneous head and neck carcinoma with perineural invasion (PNI), with the aim of developing risk-adapted treatment guidelines. A total of 118 patients were treated with RT between April 1992 and July 2000. Ninety-seven patients had PNI discovered through histology (pPNI) and 21 patients had symptoms/signs of PNI (cPNI). All received RT (median dose, 55 Gy; range, 17-74): 114 postoperatively and 4 definitively. Median follow-up was 84 months (range, 4-201). The 5-year local control (LC) rates were 90% with pPNI and 57% with cPNI (p < .0001). The pPNI and cPNI groups also differed in relapse-free survival (76% vs 46%, p = .003), disease-specific survival (90% vs 76%, p = .002), and overall survival (69% vs 57%, p = .03). pPNI patients with BCC histology (n = 42) had better LC (97% vs 84%, p = .02) than pPNI SCC (n = 55). Surgery plus RT provides a high rate of LC in patients with pPNI, particularly those with BCC. Therapeutic improvements are needed for patients with cPNI.