SOX, UFT/LV show similar DFS in high-risk stage III colon cancer
Adjuvant chemotherapy using S-1 plus oxaliplatin (SOX) or tegafur-uracil/leucovorin (UFT/LV) led to similar disease-free survival (DFS) rates in patients with high-risk stage III colon cancer, according to updated results of the ACTS-CC 02* presented at ASCO GI 2019.
This phase III trial evaluated 955 patients with high-risk stage III colon cancer (median age, 65 years) from 260 Japanese institutions. Patients were randomly assigned to receive either SOX** (n=477) or UFT/LV*** (n=478). [ASCO GI 2019, abstract 484]
About half of the patients were diagnosed with stages IIIB or IIIC (49.1 and 49.7 percent, respectively, in the SOX group and 51.3 and 47.5 percent, respectively, in the UFT/LV group).
The overall DFS rates at 3 years were comparable between the SOX and UFT/LV groups (62.7 percent vs 60.6 percent, hazard ratio [HR], 0.90, 95 percent confidence interval [CI], 0.74–1.09; p=0.28), specifically among patients with stage IIIB (68.5 percent vs 69.3 percent, HR, 1.01, 95 percent CI, 0.74–1.37; p=0.95).
While not statistically significant, patients with stage IIIC (55.8 percent vs 50.6 percent, HR, 0.82, 95 percent CI, 0.63–1.06; p=0.12) and stage N2b (54.7 percent vs 46.0 percent, HR, 0.76, 95 percent CI, 0.55–1.05; p=0.10) on SOX exhibited a trend towards better DFS than those on UFT/LV.
“The ACTS-CC 02 trial was designed to verify the superiority of postoperative adjuvant chemotherapy with SOX over LV, one of the standard oral fluoropyrimidine regimens in Japan, in terms of DFS in patients with high-risk stage III colon cancer,” said study lead author Dr Takao Takahashi from the Department of Surgical Oncology at Gifu University Graduate School of Medicine in Gifu, Japan.
“SOX was not shown to be superior to UFT/LV in patients with high-risk stage III colon cancer. However, the oxaliplatin-based regimen was suggested to be effective in more advanced disease, such as stages IIIc and N2b,” he said.
*ACTS-CC 02: A randomized phase III trial of S-1/oxaliplatin (SOX) versus UFT/leucovorin as adjuvant chemotherapy for high-risk stage III colon cancer
**SOX: Initial dose at 100 mg/m2 of oxaliplatin and 80–120 mg/day of S-1 according to body surface area (BSA) on days 1–14, every 21 days, for eight cycles
***UFT/LV: Initial dose at 300–600 mg/day of UFT according to BSA and 75 mg/day of LV on days 1–28, every 35 days, for five cycles