Can neoadjuvant radiochemotherapy improve the results of multivisceral resections in advanced rectal carcinoma (cT4a)

To investigate the influence of neoadjuvant radiochemotherapy (nRCT) in advanced rectal carcinoma (cT4a), the prospectively collected data of all patients treated by extended multivisceral resections during the last 16 years were analysed.

Between 1985 and 2000, 113 patients with clinical T4a rectal carcinoma (invasion of adjacent organs or structures), were treated by extended multivisceral surgery. In 1995 nRCT was introduced as a standardized treatment modality in cT4a carcinomas and applied in 32 patients. Six weeks after completion of nRCT, resection was performed. In all patients at least one additional organ was removed because of clinically evident tumour infiltration. In one third of patients (36/113) more than one organ had to be removed.

The rate of curative (R0) resections was 89% (101/113). It was similar in patients with and without nRCT (91 vs. 89%). In 40 (35%) patients histopathological examination could verify tumour invasion in adjacent organs (34% with vs. 36% without nRCT). The 3-year rate of locoregional recurrence after R0-resection was 12.7%. In multivariate Cox regression analysis the regional lymph node status was the most important prognostic factor (relative risk 5.8, P = 0.007). Neoadjuvant or adjuvant treatment reduced the risk by factor 0.4 (P = 0.211). The 3-year cancer-related survival rate of all patients with curative resection was 72.9%. It was 89.4% in the series treated with nRCT, while it was only 66.7% in patients with neither neoadjuvant nor adjuvant therapy. The relative risk for patients with lymph node metastases was 7.0 (P < 0.001) while it was only 0.2 in patients treated with nRCT (P = 0.049).

Together with curative extended multivisceral resection nRCT can improve prognosis in patients with advanced rectal carcinoma (cT4a).