Neoadjuvant Chemotherapy Versus Upfront Surgery for cT2N1 or cT3a-bN0-1 Middle-High Rectal Cancer

Area of Science:

• Oncology
• Surgical Oncology
• Gastrointestinal Oncology

Background:

• Optimal treatment for middle-high rectal cancer (cT2N1 or cT3a-bN0-1) without mesorectal fascia (MRF) involvement is uncertain.
• Neoadjuvant chemotherapy (NCT) and upfront surgery are guideline-suggested options, but comparative survival outcomes are unclear.

Purpose of the Study:

• To compare the survival outcomes of neoadjuvant chemotherapy (NCT) followed by surgery versus upfront surgery for middle-high rectal cancer patients without MRF involvement.

Main Methods:

• Retrospective cohort study of 514 patients treated between January 2016 and June 2023.
• Propensity score matching (PSM) was used to balance baseline characteristics, matching 201 pairs.
• Primary endpoints included disease-free survival (DFS) and metastasis-free survival (MFS).

Main Results:

• NCT followed by surgery was associated with significantly improved DFS (HR 0.50, p=0.008) and MFS (HR 0.50, p=0.01).
• Three-year DFS rates were 90.5% (NCT) vs. 81.6% (surgery); MFS rates were 92.0% (NCT) vs. 84.0% (surgery).
• Overall survival (OS) and local recurrence-free survival (LRFS) did not differ significantly between groups.

Conclusions:

• In this selected cohort, NCT followed by surgery improved DFS and MFS in middle-high rectal cancer patients without MRF involvement.
• OS and LRFS were comparable between the NCT and upfront surgery groups.
• Findings require prospective randomized validation due to the retrospective nature and potential confounding factors.