[Clinical and pathological study of esophageal mucosa with hypopharyngeal cancer]

Hypopharyngeal cancer has been reported to be frequently associated with cancer of the upper gastrointestinal tract, especially the esophagus. We recently reviewed the records of patients who had undergone closed-chest esophagectomy to assess the value of endoscopy with iodine staining as a means of preoperative diagnosis of double cancers in this area and to investigate the characteristics of the hypopharyngeal and esophageal mucosa as sites for multicentric carcinogenesis. The subjects of this study were 30 patients who had undergone closed chest esophagectomy between January 1992 and December 1995 because of hypopharyngeal cancer. The following results were obtained: 1. Preoperative iodine staining often revealed the presence of cancer, with unstained areas covering more than half the circumference of the esophagus and being more than 3 cm in size. 2. Esophageal cancer and hypopharyngeal cancer were detected concurrently in 15 cases (synchronous double cancer) and at different times in 6 cases (metachronous double cancer). Synchronous esophageal cancer was more common in cases of advanced hypopharyngeal cancer, especially Stage IV. 3. When the number of cancer foci, their distribution along the circumference of the esophagus, and the extent of tumor spread in the esophagus were investigated, multiple and localized foci smaller than 1 cm were found to be more common in synchronous cancer, and solitary foci were more common in metachronous cancer. 4. The second primary esophageal cancer often occupied the Im or Ei area, and in metachronous double cancer, it was often localized in the middle and/or inferior segment of the esophagus. 5. In 60% of cases of synchronous double cancer, the esophageal cancer was confined to the mucosa. The esophageal cancer was early stage in 86.7% of cases of synchronous double cancer. These findings allow us to draw the following conclusions: (i) Because esophageal cancer which occurs synchronously with hypopharyngeal cancer tends to recur, it is suggested that a technique that allows complete extraction of the esophagus be selected. (ii) Local treatment such as endoscopic mucosal resection should be selected in metachronous early double cancer. (iii) Unstained areas extending along more than half the circumference of the esophagus and more than 3 cm in size suggest a high probability of the presence of cancer in this area. Adequate examination is needed in such cases. (iv) Screening of the upper gastrointestinal tract is important to detect head and neck cancer. An adequate examination schedule, tailored to the features of individual cases, seems essential.