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Second head and neck cancers and tobacco usage.

OBJECTIVES
To examine the relative incidence of second primary carcinomas in patients who continued smoking compared with those who had ceased smoking.


METHODS
This is a retrospective study based on review of the Wake Forest University-Baptist Medical Center Tumor Registry for the years 1985 through 2000. Ninety-one patients who had had an index head and neck tumor and who developed a second independent head and neck primary tumor, were identified. These cases were grouped into synchronous (different sites within 6 months) and metachronous (different site after 6 months or same site after 3 years) second tumors and were examined with respect to smoking history-specifically whether smoking had continued or ceased after the diagnosis of the index tumor.


RESULTS
Of the 91 patients identified with double head and neck tumors, 88 were tobacco users. Comprising the group of 54 patients with metachronous second primaries were 51 smokers-25 who had continued and 26 who had ceased tobacco use. Of the 26 patients who had quit smoking but had developed a second primary, 13 had stopped smoking even before the index primary had been diagnosed. The remaining 13 had stopped when the index primary was treated.


CONCLUSIONS
A review of 91 patients with double head and neck primary tumors indicate no difference in the frequency of second tumors developing in a group of patients who continued to smoke after diagnosis of their index cancers relative to patients who stopped smoking. This finding suggests a critical cellular level of cumulative and persistent damage. Methods to reverse this genetic alteration are hypothesized to be potentially more significant than smoking cessation efforts in preventing subsequent head and neck cancers.