A Prognostic Nomogram for T3N0 Rectal Cancer After Total Mesorectal Excision to Help Select Patients for Adjuvant Therapy

Abstract

BackgroundThe recurrence rate of T3N0 rectal cancer after total mesorectal excision (TME) is relatively low, meaning that not all patients need adjuvant therapy (AT) (radiotherapy, chemotherapy, or chemoradiotherapy).MethodsPatients diagnosed with pT3N0M0 rectal cancer after TME were analyzed using the SEER database, of which 4367 did not receive AT and 2794 received AT. Propensity score matching was used to balance the two groups in terms of confounding factors. Cox proportional hazards regression analysis was used to screen independent prognostic factors, which were then used to establish a nomogram. The patients were then divided into three groups with X-tile software according to their risk scores. We enrolled 334 patients as external validation.ResultsThe C-index of the model was 0.725 (95% confidence interval: 0.694–0.756). We divided the patients into three different risk layers based on the nomogram prediction scores, and found that AT did not improve the prognosis of low- and moderate-risk patients, while high-risk patients benefited from AT. External validation data also support the above conclusions.ConclusionThis study developed a nomogram that effectively and comprehensively evaluates the prognosis of T3N0 rectal cancer patients after TME. After using the nomogram, we recommend AT for high-risk patients, but not for low- and moderate-risk patients.

Survival comparison of stage IIA rectal cancer with or without neoadjuvant therapy: a SEER database analysis with propensity score matching

“…There is growing evidence that patients with LARC benefit more from neoadjuvant CRT than surgery alone or postoperative CRT in terms of local control rates and sphincter protection ( 14 ). However, some studies have indicated that T3N0 rectal cancer patients can control local recurrence at a relatively low level with surgery alone, suggesting that these patients may not need neoadjuvant CRT ( 15 ). Although neoadjuvant CRT significantly reduced the risk of local recurrence in LARCs, the benefit of local control did not translate into a survival benefit ( 9 ).…”

“…Although neoadjuvant CRT significantly reduced the risk of local recurrence in LARCs, the benefit of local control did not translate into a survival benefit ( 9 ). Therefore, it remains controversial whether neoadjuvant CRT provides sufficient benefit to outweigh the side effects and inconvenience of treatment for patients with stage IIA rectal cancer ( 15 ).…”

“…Neoadjuvant radiotherapy should be considered if the distance between the tumor and rectal mesenteric fascia is predicted to be <1 mm on preoperative magnetic resonance imaging (MRI) ( 22 ). Studies have shown that in early, favorable cases (e.g., some early cT3N0), TME surgery alone is appropriate ( 15 ). For middle and lower stage II and III rectal cancer, preoperative radiotherapy or CRT can reduce the local recurrence rate without improving OS ( 23 ).…”