Pattern of failure in 5001 patients treated for glottic squamous cell carcinoma with curative intent - A population based study from the DAHANCA group

PURPOSE: To describe the pattern of failure in a national consecutive cohort of patients with glottic squamous cell carcinomas (SCC) treated with primary radiotherapy (RT) with curative intent over a 41-year period.

MATERIALS AND METHODS: All patients undergoing curative treatment for a glottic SCC diagnosed in Denmark between 1971 and 2011 were included and followed from the first contact with the oncology center to death or February 15, 2015.

RESULTS: 5001 patients were identified of whom 98% had primary RT. The median follow-up was 9.1 years/5.7 years (patients alive/patients who died). Ten patients were lost to follow-up. In total 1511 failures were observed; of these 93%, 11% and 5% included T site, N site, and M site, respectively. For patients diagnosed in the 70s and the 00s, respectively, the five-year incidences were: local failure (32% vs 19%), loco-regional failure (34% vs 21%), laryngectomy (26% vs 10%), laryngectomy-free survival (48% vs 62%), disease-free survival (62% vs 68%), and overall survival (62% vs 68%). The five-year incidence of ultimate failure (13-16%) remained statistically unchanged.

CONCLUSION: From the 70s to the 00s a continually improving primary disease-control was observed with a concurrent decrease in the incidence of laryngectomy. The survival rate was significantly higher in the 00s compared to the previous three decades.