386 Prevention of second primary tumors with a second generation retinoid in squamous cell carcinoma of oral cavity and oropharynx: Long term follow-up

Abstract

Retinoids exert a prophylactic action on the development of epithelial cancers when tested on human premalignant lesions, and are now used in the chemoprevention of epithelial cancers, in randomized trials. We prospectively studied 316 patients who developed squamous cell carcinoma of the head and neck, classified as T1/T2, N0/N1 ≤ 3 cm, M0. Patients were randomly assigned to receive orally, either etretinate (a loading dose of 50 mg per day the first month, followed by a dose of 25 mg per day the following months) or a placebo for 24 months. Adjuvant treatment began no later than 15 days after surgery and/or the initiation of radiotherapy. The five-year survival rate and disease free survival rate are similar in the two groups. There are no differences regarding either local, regional and distant relapses (logrank NS). After a median follow-up of 65 months. forty two patients in the etretinate group and forty in the placebo group, developed a second cancer, with respectively 18 and 17 in the head and neck region. Adjuvant treatment was definitively discontinued mainly due to toxicity in 33% of patients in the etretinate group versus 23% in the placebo group (P < 0.05). Etretinate, a second-generation retinoids, does not prevent second primary tumors in patients who have been treated for squamous cell carcinoma of oral cavity and oropharynx. Retinoids exert a prophylactic action on the development of epithelial cancers when tested on human premalignant lesions, and are now used in the chemoprevention of epithelial cancers, in randomized trials. We prospectively studied 316 patients who developed squamous cell carcinoma of the head and neck, classified as T1/T2, N0/N1 ≤ 3 cm, M0. Patients were randomly assigned to receive orally, either etretinate (a loading dose of 50 mg per day the first month, followed by a dose of 25 mg per day the following months) or a placebo for 24 months. Adjuvant treatment began no later than 15 days after surgery and/or the initiation of radiotherapy. The five-year survival rate and disease free survival rate are similar in the two groups. There are no differences regarding either local, regional and distant relapses (logrank NS). After a median follow-up of 65 months. forty two patients in the etretinate group and forty in the placebo group, developed a second cancer, with respectively 18 and 17 in the head and neck region. Adjuvant treatment was definitively discontinued mainly due to toxicity in 33% of patients in the etretinate group versus 23% in the placebo group (P < 0.05). Etretinate, a second-generation retinoids, does not prevent second primary tumors in patients who have been treated for squamous cell carcinoma of oral cavity and oropharynx.