Adjuvant chemotherapy with vincristine, cyclophosphamide, and doxorubicin after radiotherapy in local-regional nasopharyngeal cancer: results of a 4-year multicenter randomized study.

Abstract

To evaluate the effect of adjuvant chemotherapy in patients with local-regional nasopharyngeal carcinoma (NPC) (squamous or undifferentiated) in complete remission at the end of curative radiotherapy (RT) 229 patients were randomized from 1979 to 1983 in a multicenter study to no further therapy (116 patients) or a combination of vincristine, cyclophosphamide, and Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH) (VCA) for six monthly cycles (113 patients). The RT and RT + VCA groups were well balanced for median age (50 v 49 years), histology (undifferentiated carcinoma, 73% v 70%), tumor extent (tumor limited to nasopharynx, 57% v 57%), and nodal extent (negative nodes 26% v 24%, nodes in the lower cervical levels, 17% v 16%). RT was delivered to the nasopharynx, the base of the skull, and bilateral cervical nodes using a split course technique over 10 weeks up to the dose of 60 to 70 Gy in involved sites and 50 Gy to negative nodes. Response to RT was evaluated within 65 days post-RT treatment. Analysis at 48 months did not show significant difference between the two treatment groups in terms of relapse-free survival (RT, 55.8%, RT + VCA, 57.7%, P = .45) and overall survival (RT, 67.3%, RT + VCA, 58.5%, P = .13). The pattern of relapse was similar in the two treatment arms. Distant metastases were the cause of treatment failure in about 50% of relapsing patients. Although the results of the present study did not show any benefit from VCA administered after curative RT, combined systemic chemotherapy should be further explored due to the high incidence of local and distant failure after intensive RT.