Multivisceral resection as a key indicator of recurrence in locally advanced colorectal cancers with pathologic T3 tumors.

Purpose: This study aimed to elucidate the clinical outcomes of patients with pathologic T3 (pT3) and pathologic T4 (pT4) tumors who underwent radical resection with multivisceral resection (MVR) and to assess the prognostic significance of MVR in locally advanced colorectal cancers (CRCs) in pT3 and pT4 tumors.

Methods: This multicenter retrospective analysis evaluated the characteristics, clinicopathologic stages, perioperative factors, and clinical outcomes of patients who underwent primary colorectal resection. Patients were divided into 4 groups: those with a pT3 tumor who did not undergo MVR (pT3 - MVR; n = 1108), those with a pT3 tumor who underwent MVR (pT3 + MVR; n = 56), those with a pT4 tumor who did not undergo MVR (pT4 - MVR; n = 306), and those with a pT4 tumor who did underwent MVR (pT4 + MVR; n = 123). Univariate and multivariate regression analyses were performed to identify risk factors for recurrence.

Results: The pT3 + MVR group exhibited a higher 5-year recurrence rate than the pT3 - MVR group, with recurrence rates similar to those of the pT4 - MVR or pT4 + MVR groups (pT3 - MVR, 17.4%; pT3 + MVR, 31.6%; pT4 - MVR, 33.4%; pT4 + MVR, 35.1%). Multivariate analysis identified MVR as an independent risk factor for recurrence, particularly peritoneal dissemination, in pT3 tumors, whereas MVR had less effect on recurrence in pT4 tumors.

Conclusion: pT3 tumors requiring MVR had a higher recurrence rate than pT4 tumors. The surgeon's clinical assessment of potential T4 tumors requiring MVR at the time of surgery was an important prognostic indicator in advanced CRC.