Multiple primary cancers associated with esophageal carcinoma.

This study was conducted to examine the characteristics of esophageal cancers with primary synchronous or metachronous cancer in another organ. We retrospectively evaluated 744 patients who underwent esophagectomy for esophageal cancers between 1985 and 1998. The patients were divided into two groups according to whether they had multiple primary cancer (MPC) or nonmultiple primary cancer (NPC). Stage I cancer was significantly more frequent among patients with MPC than among those with NPC (P < 0.0001). Among patients with MPC, another primary cancer was found in the head and neck region in 70 (42.4%), in the stomach in 51 (30.9%), and in the colon, lung, breast, and other locations in the remaining patients. Of the 70 patients with another primary cancer in the head and neck region, 32 (45.7%) had pharyngeal cancer. Furthermore, the incidence of intraesophageal multiple cancer in the patients with primary cancer in the head and neck region was significantly higher than that in those whose other primary cancers were gastric cancer or in those with NPC (P = 0.0135. P < 0.0001). The 5-year survival rate of the patients with MPC was 51.28%, which was significantly higher than that of those with NPC (P = 0.019). In conclusion, a better knowledge of the relationships between esophageal carcinoma and cancers in other organs may lead to earlier detection of other primary cancers and improved therapeutic results.