Tegafur/Uracil

The efficacy of adjuvant chemotherapy for high-risk stage II colon cancer (CC) has not been well established. Using propensity score matching, we previously reported that the 3-year disease-free survival (DFS) rate was significantly higher in patients treated with uracil and tegafur plus leucovorin (UFT/LV) against surgery alone. We report the final results, including updated 5-year overall survival (OS) rates and risk factor analysis outcomes.

In total, 1902 high-risk stage II CC patients with T4, perforation/penetration, poorly differentiated adenocarcinoma/mucinous carcinoma, and/or < 12 dissected lymph nodes were enrolled in this prospective, non-randomized controlled study based on their self-selected treatment. Oral UFT/LV therapy was administered for six months after surgery.

Of the 1880 eligible patients, 402 in Group A (surgery alone) and 804 in Group B (UFT/LV) were propensity score-matched. The 5-year DFS rate was significantly higher in Group B than in Group A (P = 0.0008). The 5-year OS rates were not significantly different between groups. The inverse probability of treatment weighting revealed significantly higher 5-year DFS (P = 0.0006) and 5-year OS (P = 0.0122) rates in group B than in group A. Multivariate analyses revealed that male sex, age ≥ 70 years, T4, < 12 dissected lymph nodes, and no adjuvant chemotherapy were significant risk factors for DFS and/or OS.

The follow-up data from our prospective non-randomized controlled study revealed a considerable survival advantage in DFS offered by adjuvant chemotherapy with UFT/LV administered for six months over surgery alone in individuals with high-risk stage II CC.

Japan Registry of Clinical Trials: jRCTs031180155 (date of registration: 25/02/2019), UMIN Clinical Trials Registry: UMIN000007783 (date of registration: 18/04/2012).

The purpose of this study is to examine the appropriateness of MRI navigation surgery following chemoradiotherapy (CRT), including lateral pelvic lymph node dissection (LLND) for middle to low rectal cancer.

Forty-three consecutive patients with cT2-4b rectal cancer within 10 cm from the anal verge who underwent laparoscopic radical surgery following CRT (45-50.4Gy + S1 80mg/m2) from January 2014 and February 2020 were analyzed. We decided on the operative procedure, including LLND, based on the restaging MRI. We examined the rates of 3-year postoperative local pelvic recurrence, permanent stoma, and recurrent risk factors (Group S). We also compared the results to that of the fourteen patients who enrolled in the previous phase II trial and underwent laparoscopic radical surgery following CRT (40Gy + S-1 (80mg/m2) or UFT (300 mg/m2)) for consecutive cT2-4b rectal cancer below the peritoneal reflection. The operative procedure was decided at the initial MRI diagnosis, and the LLND was not performed (Group P).

We had no local pelvic recurrence in Group S, and the three-year local pelvic recurrence-free survival was significantly better in Group S than P (100 % in S 85.1 % in P, p < 0.05). The permanent stoma rate was not different between the Groups, irrespective of the significantly high rate of cCRM(+) in Group S. The Cox proportional hazards model for significant factors of recurrence on the univariate analysis revealed that ycM and ycEMVI scores were independently significant (p < 0.001).

MRI navigation surgery, including LLND for rectal cancer following chemoradiotherapy, improves local control and functional preservation.