Second course of radiation for new primary head-and-neck cancer: population-based study of survival

To analyze patient and tumor characteristics, and survival of patients who received 2 courses of radiotherapy for different primary head and neck cancers (HNCs).

A total of 234 patients who underwent 2 courses of radiotherapy for different primary, localized, or regional HNCs registered in the population-based Surveillance, Epidemiology, and End Results database were identified.

The latency between first and second irradiated HNCs ranged from 0.3 to 28.8 years (median, 6.3 years). Only 22% of first irradiated HNCs were node positive, and only 22% of second irradiated HNCs were node positive. After the diagnosis of the second irradiated HNC, the 1-, 2-, and 5-year overall survivals were 68%, 40%, and 17%, respectively. The variables of gender, race, latency, and stage of second cancer did not significantly impact survival. At the time of diagnosis of second irradiated HNC, younger age (P = 0.026), later year of diagnosis (P = 0.005), and cancer-directed surgery (P = 0.032) were favorable predictors of improved survival. With Cox regression analyses, younger age (P = 0.060) and cancer-directed surgery for the second irradiated HNC (HR = 0.75, 95% CI: 0.55-1.01, P = 0.062) were borderline significantly favorable risk factors, whereas year of diagnosis (P = 0.13) was not.

From a population-based analysis, patients undergoing a second course of radiation for HNC appear to benefit from cancer-directed surgery, although this did not reach statistical significance with Cox regression analyses. The improved outcome after resection is perhaps attributable to a therapeutic benefit from surgery and/or more indolent disease among those amenable to resection.