Recurrence patterns after postoperative radiotherapy for squamous cell carcinoma of the pharynx and larynx

Conclusions: Distant metastasis was a major pattern of recurrence after postoperative radiotherapy (PORT) for squamous cell carcinoma (SCC) of the oropharynx, hypopharynx, and larynx. PORT provided good loco-regional control, with tolerable toxicities. Advanced pT and pN were unfavorable prognostic factors. Objective: To determine the clinical outcomes, and the patterns and risk factors for recurrence of SCCs of the oropharynx, hypopharynx, and larynx treated with surgery and PORT. Methods: We retrospectively reviewed 84 patients who received PORT after definitive surgery for SCC of the oropharynx, hypopharynx, or larynx between 2000 and 2010. The primary sites were the oropharynx in 25 patients, hypopharynx in 47 patients, and larynx in 12 patients. Results: The 3-year overall survival (OS), progression-free survival (PFS), and loco-regional control (LRC) rates were 64.9%, 56.7%, and 92.1%, respectively. Recurrences were observed in 27 patients: 6 patients had loco-regional recurrence and 23 patients developed distant metastasis. On multivariate analysis, pT4 and pN2c-N3 displayed significantly worse effects on OS (p = 0.02 and p < 0.01, respectively) and PFS (p = 0.02 and p < 0.001, respectively). In the acute phase, 12 patients experienced grade 3 or 4 toxicities. There were no grade 5 toxicities. Late grade 3 toxicity developed in six patients and no grade 4 or 5 toxicities were observed.