PATTERNS OF RECURRENCE AFTER NERVE-SPARING SURGERY FOR RECTAL ADENOCARCINOMA WITH SPECIAL REFERENCE TO LOCO-REGIONAL RECURRENCE

PURPOSE: Since the early 1980s to relieve functional disturbances afte r rectal excision, we have been performing nerve-sparing surgery for r ectal cancer. The aim of this study was to analyze patterns of recurre nces, especially concerning causes of local ones. Furthermore, we woul d like to address the criteria we used in patient selection to effect successful nerve-sparing surgery. METHODS: From 1982 to 1991, 306 pati ents underwent nerve-sparing operations, which may be categorized into three types: 1) total autonomic nerve preservation (125 cases), 2) co mplete pelvic nerve preservation (105 cases), and 3) partial pelvic ne rve preservation with removal of parasympathetic nerve (79 cases). Sin gle and multivariant regression analyses mere conducted to investigate patterns of recurrence, especially causes of local ones. RESULTS: Six ty-five patients (21 percent) developed recurrent tumors, 19 of which (6.2 percent) were local. Using Dukes terms, there were five patients with Dukes A, 13 with Dukes B, and 47 (35 percent) with Dukes C stages . Rate of local recurrences was 13 percent in patients with Dukes C tu mor. According to single-variant analysis of Dukes C patients, the fol lowing factors are thought to influence local recurrences: number of l ymph nodes metastases, level of primary growth, and direction of lymph atic spread. Multivariate regression analysis suggested that lymph nod e metastasis was the most important and influencing factor on local re growth (P < 0.002). CONCLUSIONS: Compared with local recurrences in so -called extended surgery, the rate of local recurrences in nerve-spari ng surgery appeared to be lower. Our current policy is aggressive appl ication of nerve-sparing surgery, even to patients with node-positive rectal cancer, taking into consideration the exact extent of cancer sp read. From the viewpoint of neuroanatomy related to mesorectum, we dis cussed patient determination for our nerve-sparing surgery.