Influence of the delay of adjuvant postoperative radiation therapy on relapse and survival in oropharyngeal and hypopharyngeal cancers.

Abstract

To determine whether the delay between surgery and the beginning of radiation therapy influences survival or the risk of local-regional relapse in oropharyngeal or hypopharyngeal squamous cell carcinomas. From 2052 patients referred to the Henri Becquerel Center for the radiation therapy of an oropharyngeal or hypopharyngeal cancer between January 1, 1981 and December 31, 1992, 420 were included in a retrospective study. Exclusion criteria were another cancer, metastasis, incomplete resection, lack of homolateral lymph node resection, or previous chemotherapy. Radiation therapy delivered 45 to 75 Gy on initial location and lymph node. Follow-up was performed until December 31, 1997. A Cox proportional hazard regression analysis was used to evaluate the prognostic factors. The delay between surgery and radiation therapy was not found to be a significant prognostic factor for survival or risk of local-regional relapse. The only parameters found to influence local-regional and survival control were margins' pathologic state (respectively p < 0.0001 and p = 0.015) and T (p < 0.0001) and N (respectively p < 0.0001 and p = 0.0004) stages. In terms of local-regional relapse only, age was a prognostic factor (p = 0.048), and a trend was noted for tumor emboli in vessels or nerves (p = 0.061). In patients with oropharyngeal or hypopharyngeal squamous cell carcinoma, the delay between surgical procedure and radiation therapy does not influence survival or risk of local-regional relapse. Radiation therapy might be subjected to complete healing in these patients.