Phase III Randomized Study of Adjuvant Biologic Therapy in Patients With Stages III/IV Head and Neck Squamous Cell Carcinoma

OBJECTIVES:

• Determine the efficacy of adjuvant isotretinoin, interferon alfa, and vitamin E, in terms of incidence of primary disease recurrence and secondary primary tumor development, in patients with stage III or IV squamous cell carcinoma of the head and neck previously treated with definitive surgical excision and/or postoperative radiotherapy.
• Determine the qualitative and quantitative toxicity of this regimen in these patients.
• Compare the overall and disease-free survival of patients treated with this regimen vs those who undergo observation only.
• Determine whether alterations of p53 gene, retinoic acid receptors, retinoid-regulated gene, and interferon-responsive genes are associated with clinical outcome in these patients.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to T stage (T1 or T2 vs T3 or T4), N stage (N0 or N1 vs N2 or N3), prior therapy (complete tumor resection vs resection and radiotherapy/chemoradiotherapy vs radiotherapy or chemoradiotherapy alone), and prior chemotherapy (yes vs no). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive oral isotretinoin once daily, interferon alfa subcutaneously 3 times weekly, and oral vitamin E 3 times daily. Treatment repeats every month for 12 courses (1 year) in the absence of disease recurrence or unacceptable toxicity.
• Arm II: Patients undergo observation only for 1 year. Patients are followed every 3 months for 2 years and then every 6 months for 3 years.

PROJECTED ACCRUAL: A total of 376 patients (188 per treatment arm) will be accrued for this study within 3.75 years.