Multicentric metachronous primary carcinoma of the upper alimentary tract in 'Biri' smokers.

Three Biri smokers with multicentric primary metachronous squamous cell carcinomas of the upper alimentary tract are presented. The susceptibility of the tissues of the upper alimentary tract to multiple malignancies, and the carcinogenic effect of radiation and Biri smoke on these tissues, are discussed. We have tried to assess the role of continuous Biri smoking in the production of a second malignancy of the upper food passages in patients who received radiotherapy for their first tumour.