Control of local and regional subclinical disease by radiation therapy.

An irradiation dose of 5000 rads in 5 weeks appears to be highly efficient for eradication of subclinical disease in the oropharynx or nasopharnyx. Irradiation alone in the range of 4500 to 5000 rads, five treatments per week, 4 1/2 to 5 weeks, appears to be greater than 90% efficient for eradicating subclinical disease for both squamous-cell carcinoma and adenocarcinoma in regional lymph nodes. The site of origin of the primary squamous-cell carcinoma or adenocarcinoma seems to be independent of the response in the regional lymph nodes. It is unknown whether concomitant elective chemotherapy will modify the dose for control required for subclinical disease in squamous-cell carcinoma or adenocarcinoma.