Background: Patients with squamous cell carcinoma of the head and neck have a high prevalence of second primary esophageal squamous cell carcinomas. This study assessed the risk of developing second primary esophageal squamous cell carcinomas in patients with squamous cell carcinoma of the head and neck based on multiplicity of Lugol-voiding lesions observed by chromoendoscopy and patient characteristics.
Methods: Three hundred eighty-nine patients with newly diagnosed squamous cell carcinoma of the head and neck were divided into 4 groups: no Lugol-voiding lesions; several (</=10) small Lugol-voiding lesions; many (>10) small Lugol-voiding lesions; and many irregularly shaped, multiform Lugol-voiding lesions. Relative risk for the development of synchronous second primary esophageal squamous cell carcinomas was investigated by using univariate and multivariate analysis. Metachronous second primary esophageal squamous cell carcinomas was also studied among 227 patients followed more than 1 year after initial examination.
Results: Fifty-four (14%) of the 389 patients were found to have synchronous second primary esophageal squamous cell carcinomas. In particular, 55% of the patients with many irregular-shaped multiform Lugol-voiding lesions had synchronous second primary esophageal squamous cell carcinomas. Univariate analysis showed that the presence of many irregular-shaped multiform Lugol-voiding lesions, drinking habit, male gender, and smoking were significant risk factors for the development of synchronous second primary esophageal squamous cell carcinomas. Multivariate analysis also revealed that many irregular-shaped multiform Lugol-voiding lesions (odds ratio: 21.4; p < 0.001) and drinking habit (odds ratio: 3.3; p < 0.02) were independent risk factors. During follow-up, 7 patients (3%) had metachronous second primary esophageal squamous cell carcinomas; 6 had many irregular-shaped multiform Lugol-voiding lesions and the seventh had many small Lugol-voiding lesions in the background mucosa.
Conclusions: The presence of numerous irregular-shaped multiform Lugol-voiding lesions was closely associated with second primary esophageal squamous cell carcinomas in patients with squamous cell carcinoma of the head and neck. This might be explained by the concept of "field cancerization." Ingestion of alcohol may play an important role in the occurrence of this phenomenon.