Background: Multiple squamous cell carcinomas in the head and neck are not such a rare phenomenon in patients. To examine if these tumors have the same genetic basis or not, we investigated genetic alterations such as allelic loss in such multiple tumors to see if they showed identical patterns.
Materials and methods: Patterns of the loss of heterozygosity at 3p, 9p and 17p loci were analyzed in multiple head and neck squamous cell carcinomas of the same patient.
Results: Metachronous laryngeal and tongue tumors of a patient were found to have identical patterns of allelic loss, while synchronous tumors of three other patients had different patterns of such loss.
Conclusion: Our data support the idea that field carcinogenesis caused by exposure of oral, laryngeal and pharyngeal mucosa to carcinogens may lead to the independent development of synchronous non-related tumors at different sites of the upper aerodigestive tract.