Predicting prognosis according to preoperative chemotherapy response in patients with locally advanced lower rectal cancer

Abstract

BackgroundNeoadjuvant chemoradiotherapy is regarded as the standard of treatment for locally advanced lower rectal cancer, although some of these cases are systemic, and distant control may be inadequate. Neoadjuvant chemotherapy could compensate for such shortcomings, potentially yielding better survival outcomes. We aimed to stratify patients into prognostic groups on the basis of preoperative factors, including response to neoadjuvant chemotherapy.MethodsWe retrospectively analyzed patients with locally advanced lower rectal adenocarcinoma (clinical stage II/III with high-risk features of distant metastasis) who were treated with neoadjuvant chemotherapy (without radiotherapy) followed by curative resection between 2010 and 2017. Reduction in tumor volume (before vs. after neoadjuvant chemotherapy) was measured using magnetic resonance imaging, and a reduction above 60% was defined as a good response. Recurrence and overall survival were evaluated.ResultsThe cohort comprised 102 patients. Good response to neoadjuvant chemotherapy was associated with better 5-year recurrence-free survival (good responders: 81.1%, poor responders: 49.0%; p = 0.001) and 5-year overall survival (good responders: 94.9%, poor responders: 80.6%; p = 0.06). In a multivariate analysis, extramural venous invasion on magnetic resonance imaging after neoadjuvant chemotherapy and a tumor volume reduction rate < 60 were found to be significantly and independently associated with worse recurrence-free survival (hazard ratio: 2.74, 95% confidence interval: 1.36–5.50, p = 0.005 and hazard ratio: 3.48, 95% confidence interval: 1.57–7.72, p = 0.002, respectively). Good responders without extramural venous invasion had the best 5-year recurrence-free and overall survival (89.0 and 93.8%, respectively). Poor responders with extramural venous invasion had the worst 5-year recurrence-free and overall survival (21.4 and 50.0%, respectively).ConclusionsReductions in tumor volume after neoadjuvant chemotherapy were associated with a better prognosis in patients with locally advanced lower rectal cancer. Extramural venous invasion was a preoperative prognostic factor.

How to measure tumour response in rectal cancer? An explanation of discrepancies and suggestions for improvement

“…This evaluation can be performed within days to weeks of the start of the intervention and prior to surgery by assessing volume effects using RECIST criteria with CT or MRI [4,5], MRI based tumour regression grading [6], and mapping macroscopic and microscopic details about tumour architecture [7,8]. Results of prospective trials showed clinical complete response (cCR) or TNM down-staging after CRT is a biomarker of more favourable oncological outcomes in LARC [9][10][11].…”

Prognostic value of serum uric acid and tumor response to induction chemotherapy in locally advanced nasopharyngeal carcinoma

“…In contrast, patients with SD/PD to IC showed that the tumor volume shrank insignificantly or rather increased. Several studies demonstrated the prognostic value of changes in the tumor volume in different types of cancers [ 24 , 25 ]. Therefore, the prognostic value of tumor response to IC in LANPC patients can be elucidated.…”

Tumor Volume Reduction Rate to Induction Chemotherapy Is a Prognostic Factor for Locally Advanced Head and Neck Squamous Cell Carcinoma: a Retrospective Cohort Study

“…In other cancer sites, such as rectal cancer, the extent of tumor volume shrinkage is an established prognostic factor. [17] , [18] In small cell lung cancer, response volume also correlated to outcome of de nitive RT. [19] In locally advanved nasopharyngeal cancer, a study found a cutoff point (12.6%) of tumor volume reduction rate after neoadjuvant chemotherpay to serve as a prognositc value for disease control, including overall survival.…”