T4N0 Colon Cancer Has Oncologic Outcomes Comparable to Stage III in a Specialized Center

National data indicate that patients with T4N0 colon carcinoma have worse oncologic outcomes than other stage II cases. Our hypothesis was that optimized surgical resection and lymph node staging in a specialized center could eliminate discrepancies in oncologic outcomes within stage II colon carcinomas. Patient characteristics and outcomes after oncologically radical colectomy for pT4N0 were compared to control groups of T1-2N1, T3N1, and T3N0 cases. Group comparisons were adjusted for age, American Society of Anesthesiologists score, tumor location, year of surgery, and duration of follow-up. Cases with at least 12 collected lymph nodes and uninvolved resection margins (R0) were analyzed separately. In addition, the T4a subgroup was compared to both T4b cases with involvement of bowel loops and with infiltration of other organs or structures. T4N0 patients had worse oncologic outcomes than T1-2N1 patients and were comparable to T3N1 patients, regardless of margins status or lymph node collection. When a T4b tumor infiltrated bowel, survival and recurrence rates were similar to T4a cases, while T4b tumors involving other organs were associated with increased recurrence rate and reduced survival. T4N0 colon carcinoma remains associated with poor oncologic outcomes, regardless of treatment in a specialized center. The biologic aggressiveness of T4N0 colon cancers and the different oncologic outcomes according to specific organ infiltration should be taken into consideration in the choice of adjuvant therapies.