AUTHOR=Zhong Xiaoling , Zeng Guohua , Zhang Lixiang , You Shuyuan , Fu Yuxiang , He Wan , Liao Guixiang 

TITLE=Prediction of pathologic complete response to neoadjuvant chemoradiation in locally advanced rectal cancer

JOURNAL=Frontiers in Oncology

VOLUME=Volume 14 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2024.1361300

DOI=10.3389/fonc.2024.1361300

ISSN=2234-943X

ABSTRACT=Purpose: To investigate the predictive factors of pathologic complete response (pCR) in locally advanced rectal cancer (LARC) patients who had been treated with neoadjuvant chemoradiation (nCRT). Methods and materials: 53 LARC patients (37 males and 16 females; age range 25 to 79 years) were selected in this retrospective study. Clinical characteristics, baseline mrTNM staging, MR gross tumor volumes (GTV) and pCR were evaluated. The diagnostic accuracy of GTV for predicting pCR was calculated. Results: Among 53 LARC patients, 15 patients achieved pCR (28.3%), while 38 patients achieved non-pCR. Only 3(5.7%) out of 53 patients did not downstaged after nCRT. GTV and tumor differentiation were the significant prognostic parameters for predicting pCR. A tumor volume threshold of 21.1 cm 3 was determined as a predictor for pCR, with a sensitivity of 84% and specificity of 47%. In addition, GTV was associated with mrN stage, circumferential resection margin (CRM) status, extramural vascular invasion (EMVI) status and pretreatment serum CEA level. Conclusions: Tumor volume and tumor differentiation have significant predictive values in preoperative assessment of pCR among LARC patients. These findings aid clinicians to discriminate those patients who may probably benefit from preoperative regimens and to make optimal treatment plans.