Neoadjuvant chemotherapy for locally advanced colon cancer did not improve survival but showed some favorable outcomes, phase 3 study results showed.
For patients with locally advanced colon cancer, upfront surgery is standard of care. Adjuvant chemotherapy is added to reduce the risk for recurrence in patients with risk factors. However, neoadjuvant chemotherapy is a widely accepted approach in numerous cancers. Potential benefits of neoadjuvant chemotherapy are the elimination of micrometastases, reduction of tumor size, prehabilitation before surgery, and reduction of adjuvant chemotherapy.
The aim of the phase 3 NeoCol (NCT01918527) study was to assess the impact of neoadjuvant chemotherapy in locally advanced colon cancer compared with standard upfront surgery. The primary endpoint was disease-free survival. Lars Hendrik Jensen, MD, PhD, presented the preliminary results at the 2023 ASCO Annual Meeting, held June 2-6 in Chicago.
The study enrolled 250 patients with T3 (with invasive depth >5 mm) or T4 colon cancer. The participants were randomly assigned 1:1 to upfront surgery (arm A) or neoadjuvant chemotherapy (3 cycles CAPOX) followed by surgery (arm B). Adjuvant chemotherapy in both arms was chosen based on the pathologic stage of the cancer (minus any neoadjuvant cycles).
The primary endpoint of the study was not met. Disease-free survival and overall survival did not differ in arm A versus arm B. The total number of chemotherapy cycles was trend-wise lower in arm B compared with arm A: 4.8 versus 5.9 (P=0.06); the number of postoperative cycles was significantly lower in arm B compared with arm A: 4.1 versus 5.9 (P<0.001). Surgical complications were lower in arm B than arm A, including ileus (3% vs 8%, respectively) and anastomotic leakage (2% vs 8%, respectively). Neoadjuvant therapy resulted in downstaging of the tumor: 10% T2 or lower in arm B compared with 4% in arm A; and 59% N0 in arm B compared with 48% in arm A. In arm B, 59% of patients fulfilled the criteria for adjuvant chemotherapy compared with 73% in arm A. Fewer patients in arm B had neuropathy compared with arm A.
“Neoadjuvant chemotherapy is not superior to standard upfront surgery in locally advanced colon cancer concerning survival,” concluded Dr. Jensen. “However, the neoadjuvant approach may have favorable outcomes in the number of chemotherapy cycles, risk of chemotherapy toxicity, and some surgical complications and in downsizing and downstaging. Therefore, neoadjuvant chemotherapy could be offered as a viable treatment option.”
Copyright ©2023 Medicom Medical Publishers
