Laparoscopic colorectal resection for cancer: effects of conversion on long-term oncologic outcomes.

BACKGROUND: The effects of conversion to open surgery during laparoscopic resection for colorectal cancer on long-term oncologic outcomes still are unclear.

METHODS: All 450 laparoscopic colorectal resections for cancer performed at a single center between 1994 and 2008 and included in a prospectively maintained database were considered. Patients who required conversion to open surgery (CONV) were matched 1:2 with laparoscopically completed cases (LAP) and 1:5 with open surgery cases (OPEN) for age, American Society of Anesthesiologists (ASA) score, year of surgery, tumor location, and tumor stage. Fisher's exact, chi-square, and Wilcoxon tests were used as appropriate. Kaplan-Meier curves were compared to analyze survival.

RESULTS: In this study, 31 CONV cases were independently compared with 62 LAP and 155 OPEN cases. Compared with the LAP and OPEN patients, the CONV patients were characterized by a numerically higher rate of preoperative comorbidity (61.3% vs LAP, 51.6; P = 0.4 and OPEN, 48.4%; P = 0.2), male gender (77.4% vs LAP, 59.7%; P = 0.09 and OPEN, 58.1%; P = 0.05), and a significantly higher mean body mass index (29.6 vs LAP, 26.8; P = 0.012 and OPEN, 28.8; P = 0.3). The pathologic tumor stage, location, and chemotherapy and radiotherapy rates were comparable among the groups. After a median follow-up period of 4.1, 4.2, and 4.6 years, the 5-year disease-free survival rate was significantly lower for the CONV patients (40.2%) than for the LAP (70.7%, P = 0.01) or the OPEN (63.3%, P = 0.04) patients. However, the 5-year cancer-specific survival rates were similar among the CONV (94.4%), LAP (86.1%, P = 0.36), and OPEN (84.9%, P = 0.14) patients.

CONCLUSIONS: Conversion to open surgery does not affect oncologic outcomes, although CONV patients have increased comorbidity rates affecting long-term mortality.