CURATIVE TREATMENT OF GASTROINTESTINAL CANCER .1. THE SURGEON AS A PROGNOSTIC VARIABLE

Gastric, colon and rectal cancers are different clinical entities but similarities do exist concerning the patterns of treatment failure. Th e surgeon must accept that cure is unlikely for patients with tumors a ggressively spreading along lymphatic, hematogenous and transperitonea l routes. Surgery cannot control occult metastases at key-disseminatin g sites outside the margins of resection. With a balanced risk-benefit ratio in mind the goal of surgery for primary cancer should be contai nment of the malignancy during its complete resection. Tumor biology i s important in assessing prognosis. However, the hypothesis presented in this manuscript suggests that technical factors practiced by the su rgeon constitute an important prognostic variable. These technical fac tors as a group compete with tumor biology as the most important deter minator of prognosis. To optimize the resection of a gastric, colon or rectal cancer some or all of the following strategies should be pursu ed to minimize the risk of local and intraabdominal dissemination: 1. Preservation of mesodermal planes; 2. Extended lymphadenectomy to incr ease the rate of complete resection of lymph node metastases thus decr easing local recurrence rate (Optimal extent of lymphadenectomy remain s to be determined but overly aggressive high mortality resections are to be avoided); 3. Other technical maneuvers to minimize spillage of malignant cells include electrosurgery for both dissection and hemosta sis, preliminary ligation of the major arteries, en bloc resection of involved adjacent structures, and wide exposure using self retaining r etractors. The level of skill with which the surgeon combines all thes e surgical maneuvers will profoundly affect survival. Nevertheless, su rgical technique alone may not be able to eliminate cancer cell spill all together, eliminate the free intraperitoneal cancer cells shed fro m the tumor prior to resection, as well as control occult liver metast asis. Maximally curative surgical effort may require surgically direct ed perioperative chemotherapy (see Part 2) as part of the treatment of resectable disease. Continued studies of the patterns of surgical tre atment failure after presumably curative resection will help to develo p the criteria for selection of patients who will require further ''ad juvant'' treatment.