Clinical outcome of neoadjuvant chemoradiation in rectal cancer treatment

Abstract

To determine the clinical and pathological outcome of locally advanced rectal cancer patients treated with neoadjuvant chemoradiation (chemoradiotherapy [CRT]) followed by curative surgery and to identify predictive factors of pathological complete response (pCR). Locally advanced rectal cancer patients undergoing CRT followed by curative surgery from January 2012 to December 2017 were included. Patient's demographic data, pretreatment tumor characteristics, type of CRT regimens, type of surgery, postoperative complications, pathological reports and follow up records were analyzed. Univariate and multivariate analyses were applied to identify predictive factors for pCR. Five-year disease free and overall survival were estimated by Kaplan–Meier method and compared between pCR and non-pCR groups. A total of 85 patients were analyzed. Eighteen patients (21.1%) achieved pCR. The sphincter-saving surgery rate was 57.6%. After univariate analyses, tumor length >4 cm ( P = .007) and positive lymph nodes ( P = .040) were significantly associated with decreased rate of pCR. Complete clinical response was significantly associated with higher rate of pCR ( P = .015). Multivariate analyses demonstrated that tumor length >4 cm ( P = .010) was significantly associated with decreased rate of pCR. After a median follow-up of 65 months (IQR 34–79), the calculated 5-year overall survival and disease-free survival rates were 81.4% and 69.7%, respectively. Patients who achieved pCR tend to had longer 5-year disease-free survival ( P = .355) and overall survival ( P = .361) than those who did not. Tumor length >4 cm was associated with decreased rate of pCR in locally advanced rectal cancer who had CRT followed by surgery. Longer waiting time or more intense adjuvant treatment may be considered to improved pCR and oncological outcomes.

Cytokeratin 7 Expression and Mismatch Repair Status for Survival Prediction in Patients With Low Rectal Cancer After Neoadjuvant Therapy

“…Suwanthanma et al reported that tumor length >4 cm was associated with a low rate of pCR in rectal cancer followed by CRT. 36 Hsu et al revealed that, for patients with locally advanced rectal cancer receiving preoperative nCRT, tumor compactness is a useful radiomic parameter for improving the volumetric-based prediction model. 37 Multivariate analysis in our study showed that a larger proportion of tumors in the intestinal lumen (≥1/2) were an independent factor influencing OS and DFS.…”

The immune microenvironment landscape shows treatment-specific differences in rectal cancer patients

“…New clinical trials with different combinations of chemotherapy and, especially, wait intervals provide promising results, in some cases reaching 28% pCR rates ( 6 ). In general, longer waiting time after initial treatment and more intense local therapy are considered to improve pCR and several oncological outcomes ( 9 ).…”