Impact of interval between neoadjuvant chemoradiotherapy and surgery in rectal cancer patients

Determining the optimal interval between neoadjuvant radiochemotherapy and surgery in rectal cancer: a retrospective cohort study

INTRODUCTION

In locally advanced rectal cancer, the optimal interval between completion of neoadjuvant radiochemotherapy (RT-ChT) and surgical resection remains unclear due to contradictory data on the benefits of extending this interval. Therefore, the aim of this retrospective study was to determine the impact of this interval on outcomes in patients treated for rectal cancer at our center.

METHODS

We retrospectively reviewed 382 consecutive patients treated for stage II/III rectal cancer between October 1, 2012, and December 31, 2017. We evaluated four different cut-off points (56, 63, 70, and 77 days) to determine which had the greatest impact on treatment outcomes.

RESULTS

The median time between completion of RT-ChT and surgery was 67.2 days (range, 28-294). Intervals > 8 weeks (56 days) were associated with worse therapeutic outcomes. Specifically, an interval ≥ 77 days was associated with a significant decrease in overall survival (OS; 84% vs. 70%; p = 0.004), which is why we selected this interval for the comparative analysis. Several outcome variables were significantly better in the short interval (< 77 days) group, including margin involvement (5.2% vs. 13.9%; p = 0.01), sphincter preservation (78% vs. 59.3%; p = 0.003), and distant dissemination (22.6% vs. 32.5%; p = 0.04). No significant between-group differences were found in complete/nearly complete response rates (19.2% vs. 24.4%; p = 0.3). Time to surgery was statistically significant on both the univariate and multivariate analyses.

CONCLUSIONS

Our findings suggest that surgery should not be delayed more than 8 weeks (56 days) after neoadjuvant treatment. An interval > 8 weeks should only be considered in patients who demonstrate a good response to neoadjuvant RT-ChT.

Total neoadjuvant treatment to increase the clinical complete response rate for distal locally advanced rectal cancer (TESS): A study protocol of a prospective, open-label, multicenter, single-arm, phase 2 trial

BACKGROUND

Standard treatment of locally advanced rectal cancer (LARC) was neoadjuvant chemoradiotherapy (CRT), followed by total mesorectal excision (TME). Total neoadjuvant treatment (TNT), a new concept, attempts to deliver both systemic chemotherapy and neoadjuvant CRT prior to surgery. Patients treated with neoadjuvant chemotherapy were more likely to show higher tumor regression. The objective of this trial was to increase complete clinical rate (cCR) for LARC patients by optimizing tumor response, using TNT regimen as compared to conventional chemoradiotherapy. TESS, a prospective, open-label, multicenter, single-arm, phase 2 study, is underway.

METHODS

Main inclusion criteria include cT3-4aNany or cT1-4aN+ rectal adenocarcinoma aged 18-70y; Eastern Cooperative Oncology Group (ECOG) performance 0-1; location ≤5 cm from anal verge. Ninety-eight patients will receive 2 cycles of neoadjuvant chemotherapy Capeox (capecitabine + oxaliplatin) before, during, and after radiotherapy 50Gy/25 fractions, before TME (or other treatment decisions, such as Watch and Wait strategy) and adjuvant chemotherapy capecitabine 2 cycles. Primary endpoint is the cCR rate. Secondary endpoints include ratio of sphincter preservation strategy; pathological complete response rate and tumor regression grade distribution; local recurrence or metastasis; disease-free survival; locoregional recurrence-free survival; acute toxicity; surgical complications; long-term anal function; late toxicity; adverse effect, ECOG standard score, and quality of life. Adverse events are graded per Common Terminology Criteria for Adverse Events V5.0. Acute toxicity will be monitored during antitumor treatment, and late toxicity will be monitored for 3 years from the end of the first course of antitumor treatment.

DISCUSSION

The TESS trial aims to explore a new TNT strategy, which is expected to increase the rate of cCR and sphincter preservation rate. This study will provide new options and evidence for a new sandwich TNT strategy in patients with distal LARC.

Use of ileostomy versus colostomy as a bridge to surgery in left-sided obstructive colon cancer: retrospective cohort study

BACKGROUND

Colorectal cancer causes the majority of large bowel obstructions and surgical resection remains the gold standard for curative treatment. There is evidence that a deviating stoma as a bridge to surgery can reduce postoperative mortality rate; however, the optimal stoma type is unclear. The aim of this study was to compare outcomes between ileostomy and colostomy as a bridge to surgery in left-sided obstructive colon cancer.

METHODS

This was a national, retrospective population-based cohort study with 75 contributing hospitals. Patients with radiological left-sided obstructive colon cancer between 2009 and 2016, where a deviating stoma was used as a bridge to surgery, were included. Exclusion criteria were palliative treatment intent, perforation at presentation, emergency resection, and multivisceral resection.

RESULTS

A total of 321 patients underwent a deviating stoma; 41 (12.7 per cent) ileostomies and 280 (87.2 per cent) colostomies. The ileostomy group had longer length of stay (median 13 (interquartile range (i.q.r.) 10-16) versus 9 (i.q.r. 6-14) days, P = 0.003) and more nutritional support during the bridging interval. Both groups showed similar complication rates in the bridging interval and after primary resection, including anastomotic leakage. Stoma reversal during resection was more common in the colostomy group (9 (22.0 per cent) versus 129 (46.1 per cent) for ileostomy and colostomy respectively, P = 0.006).

CONCLUSION

This study demonstrated that patients having a colostomy as a bridge to surgery in left-sided obstructive colon cancer had a shorter length of stay and lower need for nutritional support. No difference in postoperative complications were found.

Interval time between neoadjuvant chemotherapy and surgery in advanced gastric cancer doesn't affect outcome: A meta analysis

Background

The efficacy of neoadjuvant chemotherapy for advanced gastric cancer is not yet firmly confirmed, but the exciting results demonstrated in several clinical studies have led neoadjuvant chemotherapy as the important treatment methods in guidelines. The 4-6 weeks interval time is currently the most commonly used in clinical treatment, but there are insufficient studies to support this time and the optimal interval has not yet been identified. The aim of this meta-analysis was to investigate the short-term life quality and long-term prognostic impact of the interval time between the end of neoadjuvant chemotherapy and surgery in patients with advanced gastric cancer.

Methods

We conducted a systematic literature search in PUBMED, Embase and Cochrane Liabrary for studies published or reported in English from January 2006 to May 2022. We summarised relevant studies for the time to surgery (TTS), included as retrospective studies and prospective studies. The primary study outcome was the rate of pathological complete response (pCR), and the secondary outcomes included R0 resection rate, incidence of serious postoperative complications, 3-year progression free survival time (PFS) rate and overall survival time (OS) rate. TTS were classified in three groups: 4-6 weeks, <4 weeks and >6 weeks. The ratio ratios (ORs) were calculated and forest plots and funnel plots were made to analysis by using fixed-effect and random-effect models in Review Manager 5.2.

Results

A total of five studies included 1,171 patients: 411 patients in shorter TTS group (<4 weeks), 507 patients in medium TTS group (4-6 weeks) and 253 patients in longer TTS groups (>6 weeks). And The results of our meta-analysis indicate that there are no significant difference between the three groups. The pCR, R0 resection rate, incidence of serious postoperative complications, 3-year PFS and OS were similar between three groups.

Conclusions

Although there many studies exploring the suitable TTS in advanced gastric cancer, but we have not find the evidence to prove the TTS is the risk factor influencing the outcome.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022369009.

Effect of pathological complete response after neoadjuvant chemoradiotherapy on postoperative complications of rectal cancer: a systematic review and meta-analysis

BACKGROUND

Standard total mesorectal resection has become an important treatment option for locally advanced or high-risk rectal cancer after neoadjuvant chemo-radiotherapy. 15-27% of patients can achieve pathological complete response (PCR) after neoadjuvant chemo-radiotherapy (nCRT). However, the relationship between PCR and postoperative complications remains an important unsolved problem. The objective of this study was to determine whether PCR was associated with the rate of postoperative complications.

METHODS

This meta-analysis was implemented following the recommendations from Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We searched electronic literature by PubMed, EMBASE, and Google Scholar. Major outcomes of interest included anastomotic leakage, surgical-site infection, reoperation, and any postoperative complications. Other outcomes comprised postoperative hemorrhage, ileus, and mortality.

RESULTS

Eleven thousand two hundred ninety patients in 9 studies were included in the meta-analysis. The pooled analysis revealed that patients with PCR did not have a higher risk of anastomotic leakage (OR = 1.22, 95% CI 0.92-1.62, p = 0.17), reoperation (OR = 1.13, 95% CI 0.93-1.37, p = 0.22), and any postoperative complications (OR = 1.02, 95% CI 0.91-1.15, p = 0.72) than patients with non-PCR. However, the meta-analysis showed that the PCR group was superior to the non-PCR group in terms of surgical-site infection (9.38% vs. 12.44%OR = 0.68, 95% CI 0.47-0.98; p = 0.04).

CONCLUSION

PCR might not be related to the occurrence of postoperative complications in rectal cancer patients following nCRT. In addition, PCR might be associated with a lower risk of surgical-site infection.

Optimized tools and timing of response reassessment after neoadjuvant chemoradiation in rectal cancer

PURPOSE

Reassessment tools of response to long-course neoadjuvant chemoradiation treatment (nCRT) in patients with locally advanced rectal cancer (LARC) are important in predicting complete response (CR) and thus deciding whether a wait-and-watch strategy can be implemented in these patients. Choosing which routine reassessment tools are optimal and when to use them is still unclear and will be researched in the study.

METHODS

Altogether, 250 patients with LARC who received nCRT from 2013 to 2021 and were followed up were retrospectively reviewed. Common reassessment tools of response included digital rectal examination (DRE), clinical examination and symptoms, endoscopy, biopsy, magnetic resonance imaging (MRI), and blood biomarkers.

RESULTS

Overall, 27.20% (68/250) patients had a complete response and 72.80% (182/250) did not. The combination of MRI, endoscopy, and biopsy showed the best performance in terms of accuracy of 74% and area under the curve (AUC, 0.714, 95% CI 0.546-0.882). Reassessing through DRE and presence of symptoms failed to improve the efficacy of response reassessment. After 100 days, biopsy as an assessment tool would obtain a substantial rise in accuracy from 51.28 to 100% (p = 0.003).

CONCLUSION

The combination of MRI, endoscopy, and biopsy is suitable as the reassessment tool of response for applying a wait-and-watch strategy after long-course nCRT in patients with LARC. The accuracy of biopsy as reassessment tools would be improved if they were used over 100 days after nCRT in patients with rectal cancer.

Survival landscape of different tumor regression grades and pathologic complete response in rectal cancer after neoadjuvant therapy based on reconstructed individual patient data

BACKGROUND

Neoadjuvant therapy can lead to different tumor regression grades (TRG) in rectal cancer after neoadjuvant therapy. The purposes of this study are to investigate the relationships among TRG, pathologic complete response (pCR) and long-term survival, on the basis of reconstructed individual patient data (IPD).

METHODS

The PubMed, Embase, Ovid and Cochrane CENTRAL databases were searched. The primary endpoint was to evaluate the survival landscape of different TRGs after neoadjuvant therapy and the secondary endpoint was to evaluate the associations between pCR and survival. IPD were reconstructed with Kaplan-Meier curves.

RESULTS

The 10-year overall survival (OS) and 5-year disease-free survival (DFS) were clearly higher in the pCR group than in the non-pCR (npCR) group (80.5% vs. 48.3, 90.1% vs. 69.8%). Furthermore, the OS and DFS increased with improvement in tumor regression after neoadjuvant therapy. According to the IPD, the pCR group had longer OS (HR = 0.240, 95% CI = 0.177-0.325, p < 0.001) and DFS (HR = 0.274, 95% CI = 0.205-0.367, p < 0.001) than the npCR group. Better tumor regression was associated with better survival outcomes (p < 0.005). Direct calculation of published HR values yielded similar results.

CONCLUSIONS

Our results indicate a positive relationship between better tumor regressions and improved survival benefits among the npCR group and patients with rectal cancer achieving pCR had much longer OS and DFS than patients achieving npCR, presenting a survival landscape of different TRGs and pCR in rectal cancer after neoadjuvant therapy.

Total Neoadjuvant Therapy (TNT) versus Standard Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Total neoadjuvant therapy (TNT) is a novel approach for locally advanced rectal cancer (LARC), which attempts to deliver both systemic chemotherapy and neoadjuvant chemoradiotherapy prior to surgery. However, its efficacy and safety remain controversial in randomized controlled trials (RCTs). We conducted this meta-analysis to assess such concerns.

MATERIALS AND METHODS

Head-to-head phase II/III RCTs were searched in Embase, PubMed, Web of Science, and the Cochrane Library, as well as other sources. The primary endpoint was pathologic complete response (pCR). Secondary endpoints were disease-free survival (DFS), overall survival (OS), local recurrence-free survival, distant metastasis-free survival, and the R0 resection rate.

RESULTS

Eight phase II/III RCTs involving 2,196 patients with LARC were assessed. The primary analysis demonstrated a statistically significant improvement in the pCR rate for TNT treatment (odds ratio, 1.77; 95% confidence interval [CI], 1.28-2.45; p = .0005). TNT treatment also showed improvements in DFS and OS outcomes compared with standard chemoradiotherapy (hazard ratio [HR], 0.83; 95% CI, 0.72-0.96; p = .03 and HR, 0.88; 95% CI, 0.74-1.05; p = .15). In addition, TNT treatment showed significant efficacy in reducing the risk of distant metastasis (HR, 0.81; 95% CI, 0.68-0.95; p = .012).

CONCLUSION

The overall pCR rate may be improved with TNT compared with standard treatment. The TNT strategy may also improve DFS and OS and reduce the risk of distant metastasis.

IMPLICATIONS FOR PRACTICE

Locally advanced rectal cancer (LARC) is a relatively common disease, with a poor prognosis because of its high metastatic potential. The role of total neoadjuvant therapy (TNT) has always been controversial. This meta-analysis found that TNT in LARC is associated with a significant improvement in overall pathologic complete response rate, disease-free survival, overall survival, and distant metastasis-free survival compared with standard treatment. TNT is a promising strategy for LARC, especially for patients who have little desire for surgery.

Timing to achieve the best recurrence-free survival after neoadjuvant chemoradiotherapy in locally advanced rectal cancer: experience in a large-volume center in China

AIM

To identify the optimal interval from the end of neoadjuvant chemoradiotherapy to surgery (CRT-surgery interval) based on long-term oncological outcome of locally advanced rectal cancer (LARC).

METHODS

Retrospective data analysis is reported from patients diagnosed with cT3 or T4 or TxN+ rectal cancer who underwent neoadjuvant treatment and curative-intent surgery between January 2010 and December 2018. With a priority focus on the effect of interval on oncological prognosis, we used recurrence-free survival (RFS) as the primary endpoint to determine the best cutoff point of time intervals. Then, the short-term and long-term outcomes of patients from longer and shorter interval groups were compared.

RESULTS

Data from 910 patients were analyzed, with 185 patients who achieved pCR (20.3%). The trend for increased rates of pCR for groups with a prolonged time interval was not observed (P = 0.808). X-tile determined a cutoff value of 10.5 weeks, and the population was divided into longer (> 10 weeks) and shorter (≤ 10 weeks) interval groups. The shorter interval was associated with a higher wound infection rate (4.7% vs. 1.1%, P = 0.031), but other postoperative complications did not differ between the groups. The 5-year RFS rate was significantly higher in patients in a longer group than those in the shorter weeks group (86.8% vs. 77.8%, P = 0.016). The 5-year OS rates between groups were similar (84.1% vs. 82.5%, P = 0.257). Local recurrence and lung metastases rates were higher in shorter interval group than those of longer group (local recurrence rate: 1.7% vs. 5.1%, P = 0.049; lung metastases rate: 5.7% vs. 10.7%, P = 0.047). Cox multivariate regression analysis confirmed the CRT-surgery interval (HR = 0.599, P = 0.045) to be an independent prognostic factor of RFS.

CONCLUSION

This study is the first, to the best of our knowledge, to define the optimal CRT-surgery interval based on RFS as the primary endpoint. Prolonging the waiting period to 10 weeks after the completion of CRT with additional chemotherapy cycles during the interval period might be a promising option to improve oncological survival in LARC patients treated with CRT and TME without compromising the surgical safety. Further randomized controlled trials investigating this are warranted to prove a clearly causality.