Time to adjuvant chemotherapy and survival outcomes among patients with stage 2 to 3 rectal cancer treated with preoperative chemoradiation

Adjuvant chemotherapy and survival outcomes in rectal cancer patients with good response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery: A retrospective nationwide analysis

Background

For rectal cancer, it remains unclear how to incorporate tumor response to neoadjuvant chemoradiotherapy (nCRT) when deciding whether to give adjuvant chemotherapy. In this study, we aim to determinate the survival benefit of adjuvant chemotherapy for rectal cancer patients with good response (ypT0-2N0) after nCRT and surgery.

Methods

The study cohort included 720 rectal cancer patients who had good response (ypT0-2N0) after nCRT and surgery, who did or did not receive adjuvant chemotherapy between January 2007 and December 2017, from the Taiwan Cancer Registry and National Health Insurance Research database. The Kaplan-Meier method, log-rank tests, and Cox regression analysis were performed to investigate the effect of adjuvant chemotherapy on 5-year overall survival (OS) and disease-free survival (DFS).

Results

Of 720 patients, 368 (51.1%) received adjuvant chemotherapy and 352 (48.9%) did not. Patients who received adjuvant chemotherapy were more likely to be female, younger (≤ 65), with advanced clinical T (3-4)/N (1-2) classification and ypT2 classification. No significant difference in 5-year OS (p=0.681) or DFS (p=0.942) were observed by receipt of adjuvant chemotherapy or not. Multivariable analysis revealed adjuvant chemotherapy was not associated with better OS (adjusted hazard ratio [aHR], 1.03; 95% Confidence Interval [CI], 0.88-1.21) or DFS (aHR, 1.05; 95% CI, 0.89-1.24). Stratified analysis for OS and DFS found no significant protective effect in the use of adjuvant chemotherapy, even for those with advanced clinical T or N classification.

Conclusion

Adjuvant chemotherapy may be omitted in rectal cancer patients with good response (ypT0-2N0) after nCRT and surgery.

A Single Institution Propensity Score Weighted Analysis of Time to Chemotherapy After Minimally Invasive Versus Open Colorectal Surgery

BACKGROUND

Oncologic outcomes for colon cancer are optimal when chemotherapy is started within 6 to 8 weeks after surgery. The study objective was to investigate the impact of operative modality and urgency on the time interval from surgery to adjuvant chemotherapy.

METHODS

This is a retrospective institutional tumor registry cohort study of open and laparoscopic/robotic colorectal resections for stage II-IV cancer between April 2010 and January 2018. Primary outcome was time from surgery to chemotherapy. Predictor variables were adjusted for imbalances by propensity score weighting.

RESULTS

A total of 220 patients met inclusion criteria: 171 elective (108 laparoscopic/robotic and 63 open) and 49 urgent colectomies. After propensity score weighting, there was no significant difference in time to chemotherapy between elective minimally invasive and open surgical approaches (48 days vs. 58 days, P = .187). Only 68.9% of minimally invasive and 50.8% of open colectomy patients started chemotherapy within 8 weeks of surgery. There was a significant difference (P = .037) among surgical sites with rectal resections having the longest (55 days), and right colectomies having the shortest (46 days), time to chemotherapy. Patients who had urgent operations had significantly longer hospital length of stay (P < .001) and higher post-discharge emergency department visit rates (P < .001) than the elective operation group. However, there was no significant difference in time to chemotherapy.

DISCUSSION

Neither operative modality nor operative urgency resulted in a significant difference in postoperative time to initiating chemotherapy. Future efforts should be focused on identifying postoperative recovery criteria and optimum multidisciplinary communication methods that allow recovered patients to start chemotherapy sooner.

Role of real-world evidence in informing cancer care: lessons from colorectal cancer

The term "real-world evidence" (rwe) describes the analysis of data that are collected beyond the context of clinical trials. The use and application of rwe have become increasingly common and relevant, especially in oncology, because there is growing recognition that randomized controlled trials (rcts) might not be sufficiently representative of the entire patient population that is affected by cancer, and that specific clinical research questions might be best addressed by real-world data. In this brief review, our main aim is to highlight the role of rwe in informing cancer care, particularly focusing on specific examples from colorectal cancer. Our hope is to illustrate the ways in which rwe can complement rcts in improving the understanding of cancer management and how rwe can facilitate cancer treatment decisions for real-world patients encountered in routine clinical care.

Impact of Time to Start Systemic Therapy on the Outcomes of Patients with Metastatic Colorectal Cancer Treated with First Line FOLFOX Chemotherapy; a Patient-Level Pooled Analysis of Two Clinical Trials

BACKGROUND

Impact of time to start first-line systemic chemotherapy following diagnosis of metastatic colorectal cancer (mCRC) needs to be studied.

METHODS

This is a pooled analysis of the raw data of the comparator arms of two randomized studies (NCT00272051; NCT00305188). Univariate and multivariate analyses of predictors of overall and progression-free survival were conducted through Cox regression analysis. Factors with statistically significant P value (P < 0.05) in the univariate part of the analysis were included in the multivariate analysis.

RESULTS

In univariate analysis, time to start systemic therapy did not affect overall or progression-free survival (P=0.694; P= 0.891 respectively). In multivariate analysis for overall survival, the following factors were predictive of worse overall survival: younger age (P = 0.019), higher ECOG performance score (P = 0.001), more than one site of metastatic disease (P = 0.002), colon site of the primary tumor (P = 0.004), and no oncologic surgery to the primary tumor (P < 0.001). Likewise, in multivariate analysis for progression-free survival, the following factors were predictive of worse progression-free survival: no oncologic surgery to the primary (P < 0.001), more than one organ of metastatic disease (P < 0.001), and no concurrent bevacizumab administration (P = 0.015).

CONCLUSION

Time to start systemic chemotherapy does not appear to impact overall or progression-free survival among mCRC patients.

BACCHUS: A randomised non-comparative phase II study of neoadjuvant chemotherapy (NACT) in patients with locally advanced rectal cancer (LARC)

BACKGROUND

Chemoradiation (CRT) or short-course radiotherapy (SCRT) are standard treatments for locally advanced rectal cancer (LARC). We evaluated the efficacy/safety of two neoadjuvant chemotherapy (NACT) regimens as an alternative prior to total mesorectal excision (TME).

METHODS/DESIGN

This multi-centre, phase II trial in patients with magnetic resonance imaging (MRI) defined high-risk LARC (>cT3b, cN2+ or extramural venous invasion) randomised patients (1:1) to FOLFOX + Bevacizumab (Arm 1) or FOLFOXIRI + bevacizumab (Arm 2) every 14 days for 6 cycles prior to surgery. Patients were withdrawn if positron emission tomography (PET) standardised uptake value (SUV) after 3 cycles failed to decrease by >30% or increased compared to baseline. Primary endpoint was pathological complete response rate (pCR). Secondary endpoints included adverse events (AE) and toxicity. Neoadjuvant rectal (NAR) scores based on "T" and "N" downstaging were calculated.

FINDINGS

Twenty patients aged 18-75 years were randomised. The trial stopped early because of poor accrual. Seventeen patients completed all 6 cycles of NACT. One stopped due to myocardial infarction, 1 poor response on PET (both received CRT) and 1 committed suicide. 11 patients had G3 AE, 1 G4 AE (neutropenia), and 1 G5 (suicide). pCR (the primary endpoint) was 0/10 for Arm 1 and 2/10 for Arm 2 i.e. 2/20 (10%) overall. Median NAR score was 14·9 with 5 (28%), 7 (39%), and 6 (33%) having low, intermediate, or high scores. Surgical morbidity was acceptable (1/18 wound infection, no anastomotic leak/pelvic sepsis/fistulae). The 24-month progression-free survival rate was 75% (95% CI: 60%-85%).

INTERPRETATION

The primary endpoint (pCR rate) was not met. However, FOLFOXIRI and bevacizumab achieved promising pCR rates, low NAR scores and was well-tolerated. This regimen is suitable for testing as the novel arm against current standards of SCRT and/or CRT in a future trial.

Adjuvant treatment for resected rectal cancer: impact of standard and intensified postoperative chemotherapy on disease-free survival in patients undergoing preoperative chemoradiation-a propensity score-matched analysis of an observational database

AIMS

Adjuvant chemotherapy for resected rectal cancer is widely used. However, studies on adjuvant treatment following neoadjuvant chemoradiotherapy (CRT) and total mesorectal excision (TME) have yielded conflicting results. Recent studies have focused on adding oxaliplatin to both preoperative and postoperative therapy, making it difficult to assess the impact of adjuvant oxaliplatin alone. This study was aimed at determining the impact of (i) any adjuvant treatment and (ii) oxaliplatin-containing adjuvant treatment on disease-free survival in CRT-pretreated, R0-resected rectal cancer patients.

METHOD

Patients undergoing R0 TME following 5-fluorouracil (5FU)-only-based CRT between January 1, 2008, and December 31, 2010, were selected from a nationwide registry. After propensity score matching (PSM), comparison of disease-free survival (DFS) using Kaplan-Meier analysis and log-rank test was performed in (i) patients receiving no vs. any adjuvant treatment and (ii) patients treated with adjuvant 5FU/capecitabine without vs. with oxaliplatin.

RESULTS

Out of 1497 patients, 520 matched pairs were generated for analysis of no vs. any adjuvant treatment. Mean DFS was significantly prolonged with adjuvant treatment (81.8 ± 2.06 vs. 70.1 ± 3.02 months, p < 0.001). One hundred forty-eight matched pairs were available for analysis of adjuvant therapy with or without oxaliplatin, showing no improvement in DFS in patients receiving oxaliplatin (76.9 ± 4.12 vs. 79.3 ± 4.44 months, p = 0.254). Local recurrence rate was not significantly different between groups in either analysis.

CONCLUSION

In this cohort of rectal cancer patients treated with neoadjuvant CRT and TME surgery under routine conditions, adjuvant chemotherapy significantly improved DFS. No benefit was observed for the addition of oxaliplatin to adjuvant chemotherapy in this setting.