SUBMUCOSAL TUMOR EXTENSION IN HYPOPHARYNGEAL CANCER

Objectives: To study the incidence and extent of submucosal tumor exte nsion in hypopharyngeal cancer and to evaluate the impact on the tumor recurrence and overall survival rates. Method: Fifty-seven resected s pecimens of hypopharyngeal cancer were studied in detail from January 1986 to December 1989 by use of the whole-organ, step-serial sectionin g technique. Results: Three types of submucosal tumor extension could be identified. Type I extension was characterized by a tumor with a sm ooth round contour that extended submucosally. The mucosa was thereby elevated and was detectable on gross inspection at operation. In type II extension, tongues and islands of tumor infiltrated within the subm ucosa, and these were not noticeable on gross examination. Skip metast asis in the submucosa where the submucosal tumor was completely separa ted from the main tumor bulk was classified as type III extension. Thi rty-three patients (58%) had submucosal tumor extension. The frequenci es (and extents of submucosal tumor extension) in the superior, medial , lateral, and inferior directions were 16% (3-10 mm), 37% (2-37 mm), 26% (2-37 mm), and 28% (3-35 mm), respectively. Two thirds of the subm ucosal extension was type I (22 of 33), and only 1 patient had a true skip lesion submucosally (type III extension). Type II submucosal exte nsion was found in one third of the patients (11 of 33). This occurred significantly more often in the patients who had received radiotherap y before surgery (82% [9/11]; P<.001; 95% confidence interval, 1.28-4. 44). The presence of submucosal tumor extension had no effect on the t umor recurrence and overall survival rates. Conclusions: The incidence of submucosal tumor extensions in hypopharyngeal cancer is high (58%) , but most (67%) of them can be detected grossly at operation. The pre sence of submucosal tumor extension does not adversely affect the surv ival and tumor recurrence rates.