Prognostic value of initial recurrence pattern for post-recurrence survival in locally advanced rectal cancer after...

Postoperative recurrence remains a major cause of treatment failure and death in patients with locally advanced rectal cancer (LARC), despite advances in neoadjuvant chemoradiotherapy (NCRT) and radical surgery. This study evaluated the prognostic value of initial recurrence patterns on post-recurrence survival (PRS) and examined clinicopathological factors associated with recurrence-free survival (RFS).

This retrospective study included 437 patients with LARC who underwent NCRT followed by surgery. In the cohort without preoperative metastasis, RFS was analyzed using the Kaplan-Meier method and Cox proportional hazards regression models. Among patients who developed postoperative recurrence, initial recurrence patterns were categorized as isolated lung metastasis, isolated liver metastasis, or complex recurrence based on the first site of recurrence. PRS was analyzed with the Kaplan-Meier method, and prognostic factors were identified through Cox proportional hazards regression models. A 2-year landmark analysis was conducted to assess subsequent overall survival (OS) according to recurrence status within 2 years after surgery.

Among the 437 patients, 347 remained recurrence-free, 28 had preoperative metastasis, and 62 developed postoperative recurrence. In the curative-intent cohort, multivariable Cox regression analysis indicated that pathological tumor deposit (pTD) positivity (HR, 2.37; P = 0.006) and ypTNM stage II-III (HR, 1.923; P = 0.012) were independently associated with shorter RFS. Multivariable Cox regression analysis showed that the initial recurrence pattern was independently associated with PRS. Compared with isolated lung metastasis, complex recurrence was consistently associated with poorer PRS, whereas isolated liver metastasis showed an intermediate prognosis. Kaplan-Meier analysis further revealed notable differences in PRS among recurrence patterns, with isolated lung metastasis having the most favorable outcome and complex recurrence the poorest prognosis. Additionally, recurrence within 2 years after surgery was linked to significantly lower subsequent OS in the 2-year landmark analysis.

The initial postoperative recurrence pattern was independently associated with PRS in patients with LARC following NCRT and surgery. Isolated lung metastasis was associated with relatively better outcomes, while complex recurrence indicated a poorer prognosis. In the curative-intent group, higher ypTNM stage and pTD positivity were independently associated with worse RFS. These findings may help improve postoperative risk stratification and support personalized surveillance and management.