Assessment of Optimal Treatment Strategies and Their Outcomes in T3N1 Rectal Cancers

Background: This study compares the outcomes of a surgery first vs a neoadjuvant treatment strategy in T3N1M0 rectal cancers. Methods: This was a single-centre retrospective cohort study of patients admitted for curative treatment of T3N1 rectal cancer. Patients with pre-treatment T3N1 and pathological T3N1 disease were included in the study. Patients were divided into two groups depending on whether they had surgery or neoadjuvant therapy as their initial phase of treatment. Primary outcome measures were local recurrence and distant recurrence. Secondary outcomes were disease-free survival (DFS) and overall survival (OS). Tabulated results were analyzed with appropriate statistical tests. Results: One hundred and ten patients were initially selected. Fourty-eight were finally included after excluding patients who did not meet the staging criteria or were not eligible for curative treatment. Twenty-nine patients underwent surgery, and 19 patients with neoadjuvant therapy as their first treatment. No local recurrence was noted in either group, with a distant recurrence noted in group 2 (6.9%) and group 1 (5.26%) cases among the surgery-first and neoadjuvant-first groups, respectively. Disease-free survival and overall survival were 29.5 and 30 months for the surgery-first group and 22 and 22 months for the neo-adjuvant group, respectively. Conclusions: Outcomes in the surgery-first group were non-inferior to that of the neoadjuvant group. A threatened circumferential resection margin (CRM) on pretreatment staging warrants neoadjuvant therapy to ensure an R0 resection. Extramural vascular invasion (EMVI), being a negative prognostic factor, doesn't preclude a surgery-first approach.