Prognostic significance of tumor regression in locally advanced rectal cancer after preoperative radiochemotherapy

Abstract

BackgroundThe majority of rectal cancers are discovered in locally advanced forms (UICC stage II, III). Treatment consists of preoperative radiochemotherapy, followed by surgery 6–8 weeks later and finally by postoperative chemotherapy. The aim of this study was to find out if tumor regression affected long-term survival in patients with localy advanced rectal cancer, treated with neoadjuvant radiochemotherapy.Patients and methodsPatients with rectal cancer stage II or III, treated between 2006 and 2010, were included in a retrospective study. Clinical and pathohistologic data were acquired from computer databases and information about survival from Cancer Registry. Survival was estimated according to Kaplan-Meier method. Significance of prognostic factors was evaluated in univariate analysis; comparison was carried out with log-rank test. The multivariate analysis was performed according to the Cox regression model; statistically significant variables from univariate analysis were included.ResultsTwo hundred and two patients met inclusion criteria. Median follow-up was 53.2 months. Stage ypT0N0 (pathologic complete response, pCR) was observed in 14.8% of patients. Pathohistologic stage had statistically significant impact on survival (p = 0.001). 5-year survival in patients with pCR was>90%. Postoperative T and N status were also found to be statistically significant (p = 0.011 for ypT and p < 0.001 for ypN). According to multivariate analysis, tumor response to neoadjuvant therapy was the only independent prognostic factor (p = 0.003).ConclusionsPathologic response of tumor to preoperative radiochemotherapy is an important prognostic factor for prediction of long-term survival of patients with locally advanced rectal cancer.

Total Neoadjuvant Therapy vs Standard Therapy in Locally Advanced Rectal Cancer

“…Pathologic complete response, determined by the lack of viable malignant cells in the surgically resected sample, is proposed as a pivotal prognostic criterion for long-term outcomes in LARC. 14 Patients achieving PCR after neoadjuvant treatment are less likely to have a local tumor recurrence and more likely to have a better survival outcome than patients with an incomplete response. 15 In a pooled analysis of survival outcomes for those attaining a PCR after preoperative chemoradiotherapy, 88.8% remained free of distant metastasis compared with 74.9% of patients without PCR at 5 years.…”

The impact of tumor regression grade on long-term survival in locally advanced rectal cancer treated with preoperative chemoradiotherapy

“…Similar to our findings, Omejc and Potisek reported the rate of pCR to be 14.8%, with a five-year survival rates greater than 90% in those with pCR. 31 In a metaanalysis of 12 large studies, five-year survival rates in patients with pCR were reported as high as 90.2%. Likewise, higher survival rates were observed in patients with pCR.…”

Total neoadjuvant therapy or standard chemoradiotherapy for locally advanced rectal cancer: A systematic review and meta-analysis

“…Previous studies have shown that increasing pCR may help reduce the risk of recurrence and death. Although not sufficient to replace OS, pCR is considered an important prognostic parameter for the long-term outcome of LARC (46). Recent studies have shown that TNT increases the pCR of LARC, especially for high-risk patients, such as T4 and peripheral resection margin involvement.…”