How to Achieve a Higher Pathologic Complete Response in Patients With Locally Advanced Rectal Cancer Who Receive Preoperative Chemoradiation Therapy

Can pretreatment blood biomarkers predict pathological response to neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer?

Aims: To investigate the value of previously described pretreatment hematological and biochemical biomarkers as predictors of pathological response. Methods: The authors performed a retrospective analysis of 191 patients with locally advanced rectal cancer who underwent long-course neoadjuvant chemoradiotherapy at two Portuguese centers. The authors performed logistic regression analysis to search for predictive markers of pathological complete and good response. Results: High platelet-neutrophil index (p = 0.042) and clinical tumor stage >2 (p = 0.015) were predictive of poor response. None of the analyzed biomarkers predicted pathological complete response in this study. Conclusion: A high platelet-neutrophil index before neoadjuvant chemoradiotherapy could help predict poorer pathological response in patients with locally advanced rectal cancer. However, no other blood biomarker predicted incomplete or poor response in this study.

Predictors of Pathologic Response After Total Neoadjuvant Therapy in Patients With Rectal Adenocarcinoma: A National Cancer Database Analysis

Purpose/objectives

Induction chemotherapy followed by chemoradiation and surgical resection in rectal cancer, known as total neoadjuvant therapy (TNT), is associated with improved pathologic complete response (pCR) rates. The National Cancer Database was utilized to identify factors associated with pCR and survival following treatment with TNT compared to standard neoadjuvant chemoradiation (nCRT).

Materials/methods

The National Cancer Database was queried from 2004 to 2015 for patients with locally advanced, non-metastatic rectal cancer. We identified 16,299 patients receiving neoadjuvant chemotherapy and radiation followed by definitive surgical resection. Patients were stratified by treatment received, either TNT (n=350) or nCRT (n=15,949). Multivariate binomial regression analysis and propensity matching were used to evaluate predictors of pCR. Kaplan-Meier and Cox multivariate analysis of survival were performed.

Results

Median follow-up was 38 months vs 53 months in the TNT vs nCRT groups, respectively. There were more patients with T4 or node-positive disease in the TNT group. There was a trend towards improved pCR in the TNT group (p=0.053). Patients achieving pCR had improved 5-year overall survival (OS) of 85.1%. The 5-year OS was not improved for TNT (76.2%) over nCRT (69.9%) (p=0.19). Pelvic nodal pCR was significantly higher in the TNT group (72%). When stratified by clinical stage, patients with cT3 (p=0.038) or cN1 (p=0.049) disease had improved OS with TNT.

Conclusions

Compared to nCRT, TNT is correlated with higher rates of complete pelvic nodal clearance in patients with locally advanced rectal adenocarcinoma. The use of TNT showed improved survival in patients with cT3 and cN1 disease, indicating a potential benefit for patients with less advanced disease.

Pretreatment blood biomarkers predict pathologic responses to neo-CRT in patients with locally advanced rectal cancer

Aim: To evaluate the value of pretreatment blood biomarkers in predicting pathologic responses to neoadjuvant chemoradiotherapy (neo-CRT) in patients with locally advanced rectal cancer. Materials & methods: We conducted logistic regression analysis and receiver operating characteristic to assess the predictive value of blood biomarkers. The outcome was defined by the pathologic complete response and good response. Results: Carcinoembryonic antigen (CEA) (p < 0.001), neutrophil-to-lymphocyte ratio (p = 0.024), platelet-to-lymphocyte ratio (p = 0.006) and lymphocyte-to-monocyte ratio (LMR) (p < 0.001) were significant predictors of pathologic complete response, with area under the curve of 0.785, 0.794, 0.740 and 0.913, respectively; CEA (p = 0.007) and LMR (p < 0.001) correlated significantly with good response, with area under the curve of 0.743 and 0.771, respectively. Conclusion: Lower LMR and higher CEA, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio before treatment could predict poorer pathologic response to neo-CRT in patients with locally advanced rectal cancer.