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

Surgical Outcomes in Total Neoadjuvant Therapy for Rectal Cancer Versus Standard Long-course Chemoradiation: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This systematic review and meta-analysis seeks to evaluate the impact of total neoadjuvant therapy (TNT) for rectal cancers on surgical complications and surgical pathology when compared with standard long-course chemoradiotherapy (LCRT).

BACKGROUND

The oncological benefits of TNT are well published in previous meta-analyses, but there is little synthesized information on how it affects surgical outcomes. A recent study has suggested an increase in local recurrence and higher rates of breached total mesorectal excision (TME) plane in TNT patients.

METHODS

This study conformed to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A search was performed in Medline (via PubMed), Cochrane databases, EMBASE and CINAHL to identify relevant randomized controlled trials (RCTs) comparing outcomes between TNT and LCRT. Meta-analyses of pooled proportions between TNT and LCRT were performed, comparing primary outcomes of surgical mortality, morbidity and all reported complications; surgical-pathology differences, namely mesorectal quality, R0 resection rates, circumferential resection margin positive rates, and sphincter preservation rates. Death and progression of disease during neoadjuvant treatment period was also compared. Risk of bias of RCTs was performed using the Cochrane risk-of-bias tool by 2 independent reviewers.

RESULTS

A total of 3185 patients with rectal cancer from 11 RCTs were included in the analysis: 1607 received TNT and 1578 received LCRT, of which 1422 (TNT arm) and 1391 (LCRT arm) underwent surgical resection with curative intent. There was no significant difference in mortality [risk ratio (RR)=0.86, 95% CI: 0.13-5.52, P =0.88, I2 =52%] or major complications (RR=1.04, 95% CI: 0.86-1.26, P =0.70, I2 =0%) between TNT and LCRT. There was a significantly higher risk of breached TME in TNT group on pooled analysis (RR=1.49, 95% CI: 1.03-12.16, P =0.03, I2 =0%), and on subgroup analysis there is higher risk of breached TME in those receiving extended duration of neoadjuvant treatment (>17 weeks from start of treatment to surgery) when compared with LCRT (RR=1.61, 95% CI: 1.06-2.44, P =0.03). No difference in R0 resection rates (RR=0.85, 95% CI: 0.66-1.10, P =0.21, I2 =15%), circumferential resection margin positive rates (RR=0.87, 95% CI: 0.65-1.16, P =0.35, I2 =10%) or sphincter preservation rates (RR=1.02, 95% CI: 0.83-1.25, P =0.88, I2 =57%) were observed. There was a significantly lower risk of progression of disease to an unresectable stage during the neoadjuvant treatment period in TNT patients (RR=0.60, 95% CI: 0.39-0.92, P =0.03, I2 =18%). On subgroup analysis, it appears to favor those receiving extended duration of neoadjuvant treatment (RR=0.44, 95% CI: 0.26-0.80, P =0.002), and those receiving induction-type chemotherapy in TNT (RR=0.25, 95% CI: 0.07-0.88, P =0.03).

CONCLUSIONS

TNT increases rates of breached TME which can contribute to higher local recurrence rates. TNT, however, improves systemic control by reducing early progression of disease during neoadjuvant treatment period. Further research is warranted to identify patients that will benefit from this strategy.

Total Neoadjuvant Therapy (TNT) with Full Dose Concurrent Chemotherapy in Locally Advanced Rectal Adenocarcinoma Including Signet Ring and Mucinous Cancers

PURPOSE

Total neoadjuvant therapy (TNT) with pre-operative chemotherapy and chemoradiotherapy results in improved survival and is becoming the new standard of care in locally advanced rectal cancer (LARC). We describe our experience with TNT consisting of induction chemotherapy followed by chemoradiotherapy using full dose 5FU without oxaliplatin.

METHODS

Adults with biopsy-proven, newly diagnosed LARC with high-risk characteristics on pelvic MRI (T4a or T4b, extramural vascular invasion, N2, mesorectal fascia involvement, enlargement/tumor deposits on lateral lymph nodes) were included. The TNT protocol comprised of six biweekly courses of modified FOLFOX6 followed by pelvic RT with four concurrent cycles of biweekly 5-FU 2600 mg/m2 + LV 200 mg/m2 without oxaliplatin to complete 20 uninterrupted weeks of full dose 5FU. Surgery was planned 11-13 weeks after completing chemoradiotherapy.

RESULTS

Eighty-four LARC patients, including 26% with signet-ring cell carcinoma, with high-risk MRI characteristics were treated with the TNT protocol with a 96% completion rate. Significant (> grade 3) toxicities included neutropenia (23.8%), diarrhea (14.2%) anemia (10.7%), and two deaths. The median DFS at 2 years was 22.5 months with better survival noted for those who underwent surgery or had cCR (with NOM) compared to those who did not undergo surgery (due to progression, inadequate regression, or patient preference despite residual disease) -mDFS 27.7 months versus 11.4 months, p =  < 0.0001 and mOS 29.2 months versus 15 months p =  < 0.0001.

CONCLUSION

The hybrid TNT regimen was administered without significant dose delays or interruptions. Toxicity was manageable but with two treatment-related deaths. Ability to undergo surgery after TNT predicted for improved DFS and OS.

The Impact on Survival of Neoadjuvant Treatment Interruptions in Locally Advanced Rectal Cancer Patients

The standard oncologic treatment of locally advanced rectal cancer is long-course radio-chemotherapy followed by surgery and adjuvant chemotherapy. This can result in a lengthy total treatment duration, sometimes up to one year from the diagnosis. Interruptions to neoadjuvant treatment can occur for a variety of reasons, forced or unforced. The main purpose of this study is to analyze the survival data of locally advanced rectal cancer patients who received neoadjuvant treatment and to find a cut-off point showing exactly how many days of interruption of neoadjuvant treatment the risk of death or disease relapse increases. We conducted a retrospective study on 299 patients with locally advanced rectal cancer using survival analysis (Kaplan-Meier curve and Cox regression) to determine survival probabilities for overall survival, local control, and disease-free survival. Patients with 0 to 3 days of neoadjuvant therapy interruption had a higher overall survival probability compared to patients with 4 or more days (90.2% compared to 57.9%, p-value < 0.001), hazard ratio 5.89 (p < 0.001). Local control and disease-free survival had a higher probability in patients with 0-2 days of interruption compared to people with 3 or more days (94% vs. 75.4%, and 82.2% vs. 50.5%, respectively, both p-values < 0.001). Patients with tumoral or nodal downstaging experienced fewer days of interruption than patients with no downstage. These findings reinforce the need for radiation oncologists to be well-organized when starting neoadjuvant treatment for rectal cancer, in order to anticipate and prevent potential treatment interruptions and achieve the best therapeutic results.

The role of adjuvant chemotherapy in rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy has emerged as the established treatment for locally advanced rectal cancer. Nevertheless, there remains a debate regarding the necessity of adjuvant chemotherapy for patients with locally advanced rectal cancer who exhibit a favorable tumor response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery. Thus, the objective of this study is to investigate the impact of adjuvant chemotherapy on the oncological prognosis of rectal cancer patients who have a good response to neoadjuvant chemoradiotherapy.

Materials and methods

The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in the Web of Science, PubMed, and Cochrane Library databases. The primary outcomes assessed were 5-year overall survival, disease-free survival, cancer-specific survival, recurrence-free survival, local recurrence, and distant metastasis. The data was summarized using a random effects model.

Results

A meta-analysis was conducted using 18 retrospective studies published between 2009 and 2023. The studies included 9 from China and 5 from Korea, involving a total of 6566 patients with ypT0-2N0 rectal cancer after neoadjuvant chemoradiotherapy. The pooled data revealed that adjuvant chemotherapy significantly improved 5-year overall survival (OR=1.75, 95% CI: 1.15-2.65, P=0.008), recurrence-free survival (OR=1.73, 95% CI: 1.20-2.48, P=0.003), and reduced distant metastasis (OR=0.68, 95% CI: 0.51-0.92, P=0.011). However, adjuvant chemotherapy did not have a significant effect on disease-free survival, cancer-specific survival, and local recurrence in ypT0-2N0 rectal cancer. Subgroup analysis indicated that adjuvant chemotherapy was beneficial in improving overall survival for ypT1-2N0 rectal cancer (OR=1.89, 95% CI: 1.13-3.19, P=0.003).

Conclusion

The findings of the meta-analysis suggest that adjuvant chemotherapy may provide benefits in terms of oncological outcomes for rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy and radical surgery. However, further prospective clinical studies are needed to confirm these findings.

Surgical and short-term oncological safety of total neoadjuvant therapy in high-risk locally advanced rectal cancer

BACKGROUND

Management for locally advanced rectal cancer (LARC) conventionally comprises long-course chemoradiotherapy (LCCRT), total mesorectal excision (TME), and adjuvant chemotherapy. However, the RAPIDO study published in 2021 showed that total neoadjuvant therapy (TNT) led to better oncological outcomes without increased toxicity. We review the surgical and short-term oncological outcomes of patients with high-risk LARC who underwent TNT or LCCRT before TME.

METHODS

Patients with high-risk LARC who underwent TNT or LCCRT before TME between 2021 and 2022 were reviewed.

RESULTS

Thirty-five patients (66%) had TNT as per RAPIDO whilst 18 underwent LCCRT. Median follow-up was 16 months (range 5-25). Of the patients who had TNT, median age was 65 years old (range 44-79), 34 (97%) had clinical Stage 3 LARC and median height FAV was 5 cm (range 0.5-14). Nine (26%) required a dose delay/reduction due to treatment toxicity. Seven (50%) showed resolution of previously enlarged lateral nodes. Three (9%) had pathological complete response. Postoperative major morbidity was 23%, of which 4 patients required a reoperation. Six (17%) patients had disease-related treatment failure, with two having disease progression during TNT, two developed local recurrence, and two developed distal metastasis following surgery. Median duration to surgery following completion of chemotherapy was significantly shorter with TNT (36 days versus 74 days) (P < 0.001). There were no other significant differences in outcomes.

CONCLUSION

TNT is clinically safe in high-risk LARC patients with no significant difference to surgical and short-term oncological outcomes compared to LCCRT, although a higher incidence of early surgical morbidity was observed.

Protocol for a national audit of the watch-and-wait approach in patients with rectal cancer in Aotearoa New Zealand: The ACCORD study

AIM

The watch-and-wait approach is increasingly being used in the management of rectal cancer as many patients achieve a clinical complete response after neoadjuvant treatment This national, multicentre, retrospective cohort study aims to understand the use of the watch-and-wait approach in the management of rectal cancer in Aotearoa New Zealand and its associated outcomes.

METHOD

This retrospective cohort study will include patients aged 18 years and over with biopsy proven rectal adenocarcinoma diagnosed between January 2015 and December 2022 who have a clinical complete response following neoadjuvant treatment (including short-course radiotherapy, long-course chemoradiotherapy or total neoadjuvant treatment) and have been managed with a watch-and-wait approach. Data will be collected from centres that manage rectal cancer in Aotearoa New Zealand with the eligible population being identified using data linkage with the National Cancer Registry.

CONCLUSION

This multicentre, national cohort study will investigate the use of the watch-and-wait strategy for rectal cancer in Aotearoa New Zealand. Through novel data linkage approaches, these data and methods will lay the foundation for a future prospective registry and outcome-tracking initiative.

Effect of adjuvant chemotherapy on the oncological outcome of rectal cancer patients with pathological complete response

BACKGROUND

Locally advanced rectal cancer is typically treated using a combination of neoadjuvant chemoradiotherapy and total mesorectal resection. While achieving pathological complete response following neoadjuvant chemoradiotherapy has been recognized as a positive prognostic factor in oncology, the necessity of adjuvant chemotherapy for locally advanced rectal cancer patients with pathological complete response after surgery remains uncertain. The objective of this meta-analysis was to examine the impact of adjuvant chemotherapy on the oncological outcomes of rectal cancer patients who attain pathological complete response after neoadjuvant chemoradiotherapy.

METHODS

This meta-analysis followed the guidelines outlined in the preferred reporting items for systematic review and meta-analysis (PRISMA). The Web of Science, PubMed, and Cochrane Library databases were systematically searched to identify relevant literature.

RESULTS

A total of 34 retrospective studies, including 9 studies from the NCBD database, involving 31,558 patients with pathological complete response rectal cancer, were included in the meta-analysis. The included studies were published between 2008 and 2023. The pooled analysis demonstrated that adjuvant chemotherapy significantly improved overall survival (HR = 0.803, 95% CI 0.678-0.952, P = 0.011), and no heterogeneity was observed (I2 = 0%). Locally advanced rectal cancer patients with pathological complete response who underwent adjuvant chemotherapy exhibited a higher 5-year overall survival rate compared to those who did not receive adjuvant chemotherapy (OR = 1.605, 95% CI 1.183-2.177, P = 0.002). However, the analysis also revealed that postoperative ACT did not lead to improvements in disease-free survival and recurrence-free survival within the same patient population. Subgroup analysis indicated that pathological complete response patients with clinical stage T3/T4, lymph node positivity, and younger than 70 years of age may benefit from adjuvant chemotherapy in terms of overall survival.

CONCLUSIONS

The findings of this meta-analysis suggest that adjuvant chemotherapy has a beneficial effect on improving overall survival among rectal cancer patients with pathological complete response. However, no such association was observed in terms of disease-free survival and recurrence-free survival.

Trends in adoption of total neoadjuvant therapy for locally advanced rectal cancer

BACKGROUND

Total neoadjuvant chemoradiation (TNT), an accepted strategy for the treatment of locally advanced rectal cancer (LARC), was first included in guidelines in 2018. We aimed to describe trends in, and factors associated with TNT receipt.

METHODS

A retrospective cohort study of adult patients with LARC was performed using the national cancer database (2012-2020). TNT status was determined, and temporal trends analyzed. Factors associated with TNT receipt were identified by stage.

RESULTS

A total of 51,407 patients were identified; 57.3 ​% received TNT. Increasing age and comorbidities were associated with higher rates of TNT receipt. Patients with stage III disease were more likely to receive TNT (stage II OR 0.92, 95%CI 0.88-0.96). Patients were 38 ​% more likely to get TNT after guideline inclusion (OR1.38, 95%CI 1.31-1.46).

CONCLUSION

Rates of TNT were consistently above 50 ​% and rose after inclusion in the NCCN guidelines. This study establishes baseline patterns in rates of TNT for future benchmarking.

The Predictors of Complete Pathologic Response in Rectal Cancer during the Total Neoadjuvant Therapy Era: A Systematic Review

The modern rectal cancer treatment paradigm offers additional opportunities for organ preservation, most notably via total neoadjuvant therapy (TNT) and consideration for a watch-and-wait (WW) surveillance-only approach. A major barrier to widespread implementation of a WW approach to rectal cancer is the potential discordance between a clinical complete response (cCR) and a pathologic complete response (pCR). In the pre-TNT era, the identification of predictors of pCR after neoadjuvant therapy had been previously studied. However, the last meta-analysis to assess the summative evidence on this important treatment decision point predates the acceptance and dissemination of TNT strategies. The purpose of this systematic review was to assess preoperative predictors of pCR after TNT to guide the ideal selection criteria for WW in the current era. An exhaustive literature review was performed and the electronic databases Embase, Ovid, MEDLINE, PubMed, and Cochrane were comprehensively searched up to 27 June 2023. Search terms and their combinations included "rectal neoplasms", "total neoadjuvant therapy", and "pathologic complete response". Only studies in English were included. Randomized clinical trials or prospective/retrospective cohort studies of patients with clinical stage 2 or 3 rectal adenocarcinoma who underwent at least 8 weeks of neoadjuvant chemotherapy in addition to chemoradiotherapy with pCR as a measured study outcome were included. In this systematic review, nine studies were reviewed for characteristics positively or negatively associated with pCR or tumor response after TNT. The results were qualitatively grouped into four categories: (1) biochemical factors; (2) clinical factors; (3) patient demographics; and (4) treatment sequence for TNT. The heterogeneity of studies precluded meta-analysis. The level of evidence was low to very low. There is minimal data to support any clinicopathologic factors that either have a negative or positive relationship to pCR and tumor response after TNT. Additional data from long-term trials using TNT is critical to better inform those considering WW approaches following a cCR.

Total neoadjuvant therapy in rectal cancer: the evidence and expectations

Current management of locally advanced rectal cancer achieves high cure rates, distant metastatic spread being the main cause of patients' death. Total neoadjuvant therapy (TNT) employs (chemo)radiotherapy and combined chemotherapy prior to surgery to improve the treatment outcomes. TNT has been shown to reduce significantly distant metastases, increase disease-free survival by 5 - 10% in 3 years, and finally also overall survival (≈ 5% in 7 years). It proved to double the rate of pathologic complete responses, making it an attractive strategy for non-operative management to avoid permanent colostomy in patients with distal tumors. In addition, it endorses adherence to the therapy due to better tolerance and, potentially, shortens its overall duration. A number of questions related to TNT remain currently unresolved including the indications, preferred radiotherapy and chemotherapy regimens, their sequence, timing of surgery, and role of adjuvant therapy. A stratified approach may be the optimal way to go.

Outcomes Following Recent and Distant Neoadjuvant Radiation in Rectal Cancer: An Institutional Retrospective Review and Analysis of NSQIP

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) is the standard of care in locally advanced rectal cancer (LARC). However, radiation therapy is thought to increase operative difficulty due to induction of fibrosis. Total neoadjuvant therapy (TNT) protocols increase the time between completion of radiation and surgical resection which may lead to increased operative difficulty and complications.

METHODS

A single institution retrospective review of patients ≥18 years with LARC undergoing nCRT from 2015 to 2022. Patients were dichotomized in 2 cohorts: <90 days from radiation to surgery (recent radiation), and ≥90 days from radiation to surgery (distant radiation). Institutional data was compared to National Surgical Quality Improvement Program (NSQIP) rectal cancer data from 2016 to 2020. Outcomes included intraoperative complications, 30-day morbidity, and oncologic outcomes.

RESULTS

One hundred forty-six institutional patients included, 120 had recent radiation, 26 had distant radiation. Thirty-day morbidity and intraoperative complications did not differ. There was greater radial margin positivity (7% vs. 24%), fewer lymph nodes harvested (17 ± 5 vs. 15 ± 6), and a lower rate of complete mesorectal dissection (88% vs. 65%,) in distant radiation patients 3059 patients were included in NSQIP analysis, 2029 completed radiation <90 days before surgery and 1030 without radiation 90 days before surgery. Patients without radiation 90 days preoperatively had more radial margin positivity (9.2% vs. 4.6%), organ space infection (8.6% vs. 6.4%), and pneumonia (2.2% vs. 0.9%).

CONCLUSION

The present study suggests that increased time between radiation and surgery results in more challenging dissection with less complete mesorectal dissection and increased radial margin positivity without increasing technical complications.

Tumour-specific mesorectal excision for rectal cancer: Systematic review and meta-analysis of oncological and functional outcomes

BACKGROUND

Tumour-specific mesorectal excision (TSME) practice for rectal cancer only relies on small retrospective studies. This study aimed to perform a systematic review and meta-analysis to assess the oncological and functional outcomes of TSME practice.

METHODS

A systematic review protocol was drawn to include all the studies that compared partial versus total mesorectal excision (PME vs TME) practised for rectal adenocarcinoma up to 16 cm from the anal verge. A systematic literature search was conducted on EMBASE-Medline, Pubmed and Cochrane Library. Reports were screened for the study's outcomes: oncological radicality, postoperative anastomotic leak risk and functional outcomes. Included studies were appraised for risk-of-bias and meta-analysed. Evidence was rated with the GRADE approach.

RESULTS

Twenty-seven studies were included, consisting of 12325 patients (PME n = 4460, 36.2%; TME n = 7865, 63.8%). PME was performed for tumours higher than 10 cm from the anal verge in 54.5% of patients. There was no difference between PME and TME in circumferential resection margin positivity (OR 1.31, 95%CI 0.43-3.95, p = 0.64; I2 = 38%), and local recurrence risk (HR 1.05, 95%CI 0.52-2.10, p = 0.90; I2 = 40%). The postoperative leak risk (OR 0.42, 95%CI 0.27-0.67, p < 0.001; I2 = 60%) and the major low anterior resection syndrome risk (OR 0.34, 95%CI 0.28-0.40, p < 0.001; I2 = 0%) were lower after PME surgery. No difference was found in urinary incontinence (OR 0.68, 95%CI 0.13-3.67, p = 0.66) and urinary retention after early catheter removal (OR 2.00, 95%CI 0.24-16.51, p = 0.52).

CONCLUSIONS

Evidence from this meta-analysis shows that TSME for rectal cancer has good oncological results and leads to the best-fitted functional results possible for the patient's condition.

Implications of Rectal Cancer Radiotherapy on the Immune Microenvironment: Allies and Foes to Therapy Resistance and Patients' Outcome

Aside from surgical resection, locally advanced rectal cancer is regularly treated with neoadjuvant chemoradiotherapy. Since the concept of cancer treatment has shifted from only focusing on tumor cells as drivers of disease progression towards a broader understanding including the dynamic tumor microenvironment (TME), the impact of radiotherapy on the TME and specifically the tumor immune microenvironment (TIME) is increasingly recognized. Both promoting as well as suppressing effects on anti-tumor immunity have been reported in response to rectal cancer (chemo-)radiotherapy and various targets for combination therapies are under investigation. A literature review was conducted searching the PubMed database for evidence regarding the pleiotropic effects of (chemo-)radiotherapy on the rectal cancer TIME, including alterations in cytokine levels, immune cell populations and activity as well as changes in immune checkpoint proteins. Radiotherapy can induce immune-stimulating and -suppressive alterations, potentially mediating radioresistance. The response is influenced by treatment modalities, including the dosage administered and the highly individual intrinsic pre-treatment immune status. Directly addressing the main immune cells of the TME, this review aims to highlight therapeutical implications since efficient rectal cancer treatment relies on personalized strategies combining conventional therapies with immune-modulating approaches, such as immune checkpoint inhibitors.

Can neoadjuvant chemoradiotherapy combined with immunotherapy benefit patients with microsatellite stable locally advanced rectal cancer? a pooled and integration analysis

Objective

To assess the clinical efficacy of neoadjuvant chemoradiotherapy combined with immunotherapy for patients with microsatellite stable (MSS) locally advanced rectal cancer and provide evidence to support clinical decision-making.

Methods

A systematic search was conducted on the PubMed, Embase, Cochrane Collaboration databases, conference summaries, and Chinese databases for clinical studies that investigated neoadjuvant chemoradiotherapy combined with immunotherapy for the treatment of locally advanced rectal cancer with MSS status. The search spanned from the inception of each database through July 2023. Data from the identified studies were extracted using a pre-designed table, and efficacy outcomes were analyzed. An integrated analysis was conducted using Stata 12.0 software.

Results

Eight studies were included, comprising 204 patients with locally advanced MSS rectal cancer who received chemoradiotherapy combined with immunotherapy. The integrated analysis revealed a pathologic complete remission rate of 0.33, a sphincter preservation rate of 0.86, an R0 resection rate of 0.83, a major pathologic remission rate of 0.33, and a clinical complete remission rate of 0.30.

Conclusion

Neoadjuvant chemoradiotherapy combined with immunotherapy demonstrates significant short-term efficacy in MSS-type locally advanced rectal cancer, notably enhancing the pathologic complete remission and sphincter preservation rates. This combination is a recommended treatment for patients with MSS-type rectal cancer.

The benefits of adjuvant chemotherapy are associated with the kind of neoadjuvant therapy in stage ypI rectal cancer: evidence based on population analysis

PURPOSE

The oncological role of adjuvant chemotherapy (ACT) remains debated in locally advanced rectal cancer (RC) after neoadjuvant therapy (NAT), especially ypI RC. In this study, we used population-based data to evaluate the benefits of ACT in stage ypI RC after NAT and surgery. Moreover, we tried to differentiate what kind of NAT (radiotherapy alone or chemoradiotherapy) was administered because this may affect the further efficacy of ACT.

METHODS

All patients with stage ypI primary rectal malignancy were diagnosed in the SEER database between 2004 and 2017. The Kaplan-Meier method was applied to estimate the effects of ACT in survival analysis. Cox regression was performed to calculate the hazard ratio (HR) and the prognosis factors of survival. Propensity score matching (PSM) was used to balance the parameters between therapy groups.

RESULTS

The overall cohort's median follow-up time was 105 months. For 5-year OS and CSS, there were no significant differences between the ACT ( +) and ACT (-) groups (p = 0.105; p = 0.788). However, subgroup analyses according to the kind of NAT found that ACT improved overall survival (OS) and cancer-specific survival (CSS) in patients who received neoadjuvant radiotherapy (nRT) (p < 0.001, p = 0.015). Among patients who received neoadjuvant chemoradiotherapy (nCRT), no significant survival benefits were found between the ACT ( +) and ACT (-) groups (p = 0.526, p = 0.288).

CONCLUSION

Our population-based cohort study suggested that the efficacy of ACT was associated with the kind of NAT. The ACT provides survival benefits in stage ypI RC for patients who received nRT. However, among patients who received nCRT, ACT did not improve long-term survival.

Eastern Canadian Gastrointestinal Cancer Consensus Conference 2023

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2023 was held in Quebec City, Quebec 2-4 February 2023. The purpose of the conference was to develop consensus statements on emerging and evolving treatment paradigms. Participants included Canadian medical oncologists, radiation oncologists, pathologists and surgical oncologists from across Ontario, Quebec, and the Atlantic provinces. Consensus statements were developed following rapid review presentations and discussion of available literature. The recommendations proposed here represent the consensus opinions of physicians involved in the care of patients with gastrointestinal malignancies who participated in this meeting.

Validated Pretreatment Prediction Models for Response to Neoadjuvant Therapy in Patients with Rectal Cancer: A Systematic Review and Critical Appraisal

Pretreatment response prediction is crucial to select those patients with rectal cancer who will benefit from organ preservation strategies following (intensified) neoadjuvant therapy and to avoid unnecessary toxicity in those who will not. The combination of individual predictors in multivariable prediction models might improve predictive accuracy. The aim of this systematic review was to summarize and critically appraise validated pretreatment prediction models (other than radiomics-based models or image-based deep learning models) for response to neoadjuvant therapy in patients with rectal cancer and provide evidence-based recommendations for future research. MEDLINE via Ovid, Embase.com, and Scopus were searched for eligible studies published up to November 2022. A total of 5006 studies were screened and 16 were included for data extraction and risk of bias assessment using Prediction model Risk Of Bias Assessment Tool (PROBAST). All selected models were unique and grouped into five predictor categories: clinical, combined, genetics, metabolites, and pathology. Studies generally included patients with intermediate or advanced tumor stages who were treated with neoadjuvant chemoradiotherapy. Evaluated outcomes were pathological complete response and pathological tumor response. All studies were considered to have a high risk of bias and none of the models were externally validated in an independent study. Discriminative performances, estimated with the area under the curve (AUC), ranged per predictor category from 0.60 to 0.70 (clinical), 0.78 to 0.81 (combined), 0.66 to 0.91 (genetics), 0.54 to 0.80 (metabolites), and 0.71 to 0.91 (pathology). Model calibration outcomes were reported in five studies. Two collagen feature-based models showed the best predictive performance (AUCs 0.83-0.91 and good calibration). In conclusion, some pretreatment models for response prediction in rectal cancer show encouraging predictive potential but, given the high risk of bias in these studies, their value should be evaluated in future, well-designed studies.

Total neoadjuvant therapy for locally advanced rectal cancer: a narrative review

Locally advanced rectal cancer has traditionally been treated with chemoradiotherapy (CRT) followed by surgery and adjuvant chemotherapy. However, a new strategy, total neoadjuvant therapy, involves the administration of CRT and neoadjuvant chemotherapy with the aim of eradicating micrometastases earlier and achieving greater control of the disease. The use of total neoadjuvant therapy has shown higher rates of pathological complete response and resectability compared with CRT, including improved survival. Nevertheless, distant relapse is the main cause of morbidity and mortality in locally advanced rectal cancer. To address this, new biomarkers are being developed to predict disease response.

Early Age of Onset Is an Independent Predictor for a Worse Response to Neoadjuvant Therapies in Sporadic Rectal Cancer Patients

The incidence of rectal cancer (RC) is increasing in the population aged ≤ 49 (early-onset RC-EORC). EORC patients are more likely to present with locally advanced disease at diagnosis than late-onset RC (LORC; aged ≥ 50) patients. As a consequence, more EORC patients undergo neoadjuvant therapies. The response to treatment in EORC patients is still unknown. This study aims to explore the effect of age of onset on the pathological response to neoadjuvant therapies in sporadic locally advanced RC (LARC) patients. Based on an institutional prospectively maintained database, LARC patients undergoing neoadjuvant therapies and radical surgery between January 2010 and December 2022 were allocated to the EORC and LORC groups. The primary endpoint was the rate of incomplete response (Dworak 0-2). A total of 326 LORC and 79 EORC patients were included. Pre-neoadjuvant tumor features were comparable. A significantly higher rate of incomplete response was observed in EORC patients (49% vs. 35%; p = 0.028). From multivariable analysis, early age of onset, smoking and extramural invasion presented as independent risk factors for a worse response. This study demonstrates that an early age of onset is related to a worse response and calls for different multimodal strategies in this group of patients.

The Conditioning of Adjuvant Chemotherapy for Stage II and III Rectal Cancer Determined by Postoperative Pathological Characteristics in Romania

The management of locally advanced rectal cancer (LARC) suffered changes thanks to the development of improved surgical procedures, radiation delivery, and chemotherapy. Although treatment options improved individually, the optimal order is still debated. Neoadjuvant chemo-radiotherapy followed by total mesorectal excision (TME) has been the "golden standard" for locally advanced rectal cancer. There is no common ground in international guidelines on the indications of adjuvant chemotherapy (ADJCHT), with differences between the American, European, and Japanese guidelines. This paper studies the preferences of Romanian oncologists in prescribing ADJCHT. We conducted a single-institution, retrospective study of all nonmetastatic, ECOG 0-1 LARC patients staged II-III who underwent TME and were admitted to the Oncology or Radiotherapy Department of Colțea Clinical Hospital, Bucharest between January 2017 and March 2021. A total of 186 patients were included in the study. A positive correlation was found between ADJCHT and each of the following: (y)pT > 2, (y)pN > 0, and the presence of perineural invasion (PNI+). A strong positive correlation was found between ADJCHT and the presence of at least one risk factor: (y)pT > 2, (y)pN > 0, PNI+, lymphovascular invasion, positive margins, or tumor grade > 1. Tumor downstaging decreased the risk of metastases in the first 2 years and was associated with the use of neoadjuvant radiotherapy, while adding neoadjuvant chemotherapy increased the chance of nodal downstaging. ADJCHT practice for LARC in Romania follows either NCCN or ESMO guidelines, at the discretion of the oncologist, due to the lack of national guideline.

Feasibility of Perineal Defect Reconstruction with Simplified Fasciocutaneous Inferior Gluteal Artery Perforator (IGAP) Flaps after Tumor Resection of the Lower Rectum: Incidence and Outcome in an Interdisciplinary Approach

BACKGROUND

Extralevator abdominoperineal excision (ELAPE) is a relatively new surgical technique for low rectal cancers, enabling a more radical approach than conventional abdominoperineal excision (APE) with a potentially better oncological outcome. To date, no standard exists for reconstruction after extended or extralevator approaches of abdominoperineal (ELAPE) resection for lower gastrointestinal cancer or inflammatory tumors. In the recent literature, techniques with myocutaneous flaps, such as the VY gluteal flap, the pedicled gracilis flap, or the pedicled rectus abdominis flaps (VRAM) are primarily described. We propose a tailored concept with the use of bilateral adipo-fasciocutaneous inferior gluteal artery perforator (IGAP) advancement flaps in VY fashion after ELAPE surgery procedures. This retrospective cohort study analyzes the feasibility of this concept and is, to our knowledge, one of the largest published series of IGAP flaps in the context of primary closure after ELAPE procedures.

METHODS

In a retrospective cohort analysis, we evaluated all the consecutive patients with rectal resections from Jan 2017 to Sep 2021. All the patients with abdominoperineal resection were included in the study evaluation. The primary endpoint of the study was the proportion of plastic reconstruction and inpatient discharge.

RESULTS

Out of a total of 560 patients with rectal resections, 101 consecutive patients with ELAPE met the inclusion criteria and were included in the study evaluation. The primary direct defect closure was performed in 72 patients (71.3%). In 29 patients (28.7%), the defect was closed with primary unilateral or bilateral IGAP flaps in VY fashion. The patients' mean age was 59.4 years with a range of 25-85 years. In 84 patients, the indication of the operation was lower rectal cancer or anal cancer recurrence, and non-oncological resections were performed in 17 patients. Surgery was performed in a minimally invasive abdominal approach in combination with open perineal extralevatoric abdominoperineal resection (ELAPE) and immediate IGAP flap reconstruction. The rate of perineal early complications after plastic reconstruction was 19.0%, which needed local revision due to local infection. All these interventions were conducted under general anesthesia (Clavien-Dindo IIIb). The mean length of the hospital stay was 14.4 days after ELAPE, ranging from 3 to 53 days.

CONCLUSIONS

Since radical resection with a broad margin is the standard choice in primary, sphincter-infiltrating rectal cancer and recurrent anal cancer surgery in combination with ELAPE, the choice technique for pelvic floor reconstruction is under debate and there is no consensus. Using IGAP flaps is a reliable, technical, easy, and safe option, especially in wider defects on the pelvic floor with minimal donor site morbidity and an acceptable complication (no flap necrosis) rate. The data for hernia incidence in the long term are not known.

Clinical complete response maintained for more than 5 years after aggressive chemoradiotherapy for advanced rectal cancer with necrotizing fasciitis: a case report

We report the case of a 65-year-old male diagnosed with advanced rectal cancer associated with necrotizing fasciitis (NF). Since radical surgery, total pelvic exenteration with sacrectomy, was rejected because of detrimental effects on quality of life, chemoradiotherapy (CRT) was chosen as anti-cancer treatment after urgent debridement. Although CRT was paused unintentionally just after delivering the total dose of radiation owing to the relapse of NF, the patient has maintained clinical complete response (cCR) without any distant metastasis for >5 years. Advanced rectal cancer is recognized as an NF risk factor. No definitive treatment strategies have been reported for NF-inducing rectal cancer; however, some reports have demonstrated curative extended surgery. Thus, CRT may be a less-invasive treatment option for NF-inducing rectal cancer, whereas severe adverse effects including re-infection after debridement should be closely monitored.

Radioimmunotherapy in colorectal cancer treatment: present and future

Colorectal cancer (CRC) is a deadly form of cancer worldwide. Patients with locally advanced rectal cancer and metastatic CRC have a poor long-term prognosis, and rational and effective treatment remains a major challenge. Common treatments include multi-modal combinations of surgery, radiotherapy, and chemotherapy; however, recurrence and metastasis rates remain high. The combination of radiotherapy and immunotherapy (radioimmunotherapy [RIT]) may offer new solutions to this problem, but its prospects remain uncertain. This review aimed to summarize the current applications of radiotherapy and immunotherapy, elaborate on the underlying mechanisms, and systematically review the preliminary results of RIT-related clinical trials for CRC. Studies have identified several key predictors of RIT efficacy. Summarily, rational RIT regimens can improve the outcomes of some patients with CRC, but current study designs have limitations. Further studies on RIT should focus on including larger sample sizes and optimizing the combination therapy regimen based on underlying influencing factors.

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.

Selecting a TNT Schedule in Locally Advanced Rectal Cancer: Can We Predict Who Actually Benefits?

Many consider the standard of care for locally advanced rectal cancer (LARC) to be preoperative chemoradiotherapy, radical surgery involving a total mesorectal excision, and post-operative adjuvant chemotherapy based on the pathology of the specimen. The poor impact on distant control is a major limitation of this strategy, with metastasis rates remaining in the 25-35% range and recovery after radical surgery leading to reluctance with prescription and inconsistent patient compliance with adjuvant chemotherapy. A second limitation is the low rate of pathologic complete response (pCR) (around 10-15%) despite multiple efforts to potentiate preoperative chemoradiation regimens, which in turn means it is less effective at achieving non-operative management (NOM). Total neoadjuvant treatment (TNT) is a pragmatic approach to solving these problems by introducing systemic chemotherapy at an early timepoint. Enthusiasm for delivering TNT for patients with LARC is increasing in light of the results of published randomized phase III trials, which show a doubling of the pCR rate and a significant reduction in the risk of subsequent metastases. However, there has been no demonstrated improvement in quality of life or overall survival. A plethora of potential chemotherapy schedules are available around the radiotherapy component, which include preoperative induction or consolidation with a range of options (FOLFOXIRI, FOLFOX, or CAPEOX,) and a varying duration of 6-18 weeks, prior to long course chemoradiation (LCCRT) or consolidation NACT following short-course preoperative radiation therapy (SCPRT) using 5 × 5 Gy or LCCRT using 45-60 Gy, respectively. The need to maintain optimal local control is a further important factor, and preliminary data appear to indicate that the RT schedule remains a crucial issue, especially in more advanced tumors, i.e., mesorectal fascia (MRF) invasion. Thus, there is no consensus as to the optimum combination, sequence, or duration of TNT. The selection of patients most likely to benefit is challenging, as clear-cut criteria to individuate patients benefiting from TNT are lacking. In this narrative review, we examine if there are any necessary or sufficient criteria for the use of TNT. We explore potential selection for the individual and their concerns with a generalized use of this strategy.

Efficacy and safety of total neoadjuvant therapy in locally advanced rectal cancer: a meta-analysis

PURPOSE

The standard of care for locally advanced rectal cancer (LARC) has changed from a single radical surgical treatment to the current multimodality treatment (standard chemoradiotherapy (CRT) and total neoadjuvant therapy (TNT)). The efficacy and safety of both TNT and standard CRT are evaluated in randomized controlled trials (RCTs).

METHODS

RCTs were comprehensively searched in Chinese and English electronic databases. The experimental and control groups were TNT and the standard CRT, respectively, included in this meta-analysis. The outcomes were assessed through a fixed-effect or random-effect model of pooled odds (OR) or hazard ratios (HR).

RESULTS

Eleven RCTs, involving 3,101 patients were included in the final analysis. TNT showed increase in the pathological complete response (pCR) (OR = 1.95, 95% confidence interval (CI): 1.57-2.41; P < 0.05) and the R0 resection (OR = 1.19, 95% CI: 0.99-1.43; P = 0.062). There was no significant difference in local recurrence-free survival (LRFS) (HR = 0.97, P = 0.803), but TNT had better 3-year disease-free survival (DFS) (HR = 0.82, 95% CI: 0.72-0.93, P < 0.05), overall survival (OS) (HR = 0.87, 95% CI: 0.74-1.02, P = 0.08) and distant metastasis-free survival (DMFS) (HR = 0.79, 95% CI: 0.67-0.93, P < 0.05) than standard CRT.

CONCLUSIONS

TNT was safe and feasible as it improved pCR and survival outcomes, and reduced the risk of distant metastasis compared with standard CRT. TNT may be a superior strategy for LARC, but more RCTs are needed to prove it.

REGISTRATION AND PROTOCOL

PROSPERO CRD42022327697. We added the Chinese database after registration because of the inclusion of fewer RCTs www.crd.york.ac.uk/PROSPERO/ .

Neoadjuvant immunotherapy for colorectal cancer: Right regimens, right patients, right directions?

Neoadjuvant chemoradiotherapy (NACRT) or chemotherapy (NACT) followed by radical resection and then adjuvant therapy is considered the optimal treatment model for locally advanced colorectal cancer (LACRC). A recent total neoadjuvant therapy (TNT) strategy further improved the tumour regression rate preoperatively and reduced local-regional recurrence in locally advanced rectal cancer (LARC). However, distant metastasis was still high, and little overall survival benefit was obtained from these preoperative treatment models. According to mismatch repair protein expression, MSI-H/dMMR and non-MSI-H/pMMR statuses were defined in colorectal cancer (CRC) patients. Due to the special features of biologics in MSI-H/dMMR CRC patients, this subgroup of patients achieved little treatment efficacy from chemoradiotherapy but benefited from immune checkpoint inhibitors (ICIs). The KEYNOTE-177 trial observed favourable survival outcomes in metastatic CRC patients treated with one-line pembrolizumab with tolerable toxicity. Given the better systemic immune function, increased antigenic exposure, and improved long-term memory induction before surgery, neoadjuvant ICI (NAICI) treatment was proposed. The NICHE trial pioneered the use of NAICI treatment in LACRC, and recent reports from several phase II studies demonstrated satisfactory tumour downsizing in CRC. Preclinical rationales and preliminary early-phase human trials reveal the feasibility of NAICI therapy and the therapeutic efficacy provided by this treatment model. Better tumour regression before surgery also increases the possibility of organ preservation for low LARC. However, the optimal treatment strategy and effective biomarker identification for beneficiary selection remain unknown, and potential pitfalls exist, including tumour progression during neoadjuvant treatment due to drug resistance and surgery delay. Given these foundations and questions, further phase II or III trials with large samples need to be conducted to explore the right regimens for the right patients.

Long-term results of a phase 2 study of neoadjuvant chemotherapy with molecularly targeted agents for locally advanced rectal cancer

BACKGROUND

We previously reported the feasibility and efficacy of neoadjuvant chemotherapy without radiotherapy for locally advanced rectal cancer. Here, we report the results of a long-term follow-up study.

METHODS

This was a multi-institutional, prospective phase 2 study of patients with locally advanced rectal cancer. Patients received neoadjuvant chemotherapy with molecularly targeted agents before undergoing total mesorectal excision. Six cycles of modified FOLFOX (mFOLFOX6) with bevacizumab were administered to KRAS-mutant patients, and mFOLFOX6 with cetuximab was administered to KRAS-wild-type patients. Here, we report the secondary end points of overall survival, relapse-free survival, and local recurrence rate.

RESULTS

Sixty patients were enrolled in this study. R0 resection was achieved in 98.3% (59/60) patients, and pathological complete response was achieved in 16.7% (10/60) patients. After a median follow-up of 5.4 years, the 5 year overall survival was 81.6%, the 5 year relapse-free survival was 71.7%, and the 5 year local recurrence rate was 12.6%. None of the patients who achieved pathological complete response developed recurrence within 5 years.

CONCLUSIONS

The use of molecularly targeted agents in the neoadjuvant setting for locally advanced rectal cancer has an acceptable prognosis.

Predictive and Prognostic Value of Oncogene Mutations and Microsatellite Instability in Locally-Advanced Rectal Cancer Treated with Neoadjuvant Radiation-Based Therapy: A Systematic Review and Meta-Analysis

Markers of pathological complete response (pCR) to preoperative radiation-based therapy in locally advanced rectal cancer (LARC) are strongly needed. This meta-analysis aimed at elucidating the predictive/prognostic role of tumor markers in LARC. We systematically reviewed the impact of RAS, TP53, BRAF, PIK3CA, and SMAD4 mutations and MSI status on response (pCR, downstaging) and prognosis (risk of recurrence, survival) in LARC according to PRISMA guidelines and the PICO model. PubMed, Cochrane Library, and Web of Science Core Collection were systematically searched to identify relevant studies published before October 2022. KRAS mutations were significantly associated with the risk of not achieving pCR after preoperative treatment (summary OR = 1.80, 95% CI: 1.23-2.64). This association was even more significant in patients not receiving cetuximab (summary OR = 2.17, 95% CI: 1.41-3.33) than in patients receiving cetuximab (summary OR = 0.89, 95% CI: 0.39-20.05). MSI status was not associated with pCR (summary OR = 0.80, 95% CI: 0.41-1.57). No effect of KRAS mutation or MSI status on downstaging was detected. Meta-analysis of survival outcomes was not possible due to the large heterogeneity among studies in endpoint assessment. The minimum number of eligible studies to assess the predictive/prognostic role of TP53, BRAF, PIK3CA, and SMAD4 mutations was not reached. KRAS mutation, but not MSI status, proved to be a detrimental marker for response to preoperative radiation-based therapy in LARC. Translating this finding into the clinic could improve the management of LARC patients. More data are needed to clarify the clinical impact of TP53, BRAF, PIK3CA, and SMAD4 mutations.

Patterns of Care for Patients With Locally Advanced Rectal Cancer Treated with Total Neoadjuvant Therapy at Predominately Academic Centers between 2016-2020: An NCDB Analysis

Total neoadjuvant therapy (TNT) has emerged as the preferred approach for locally advanced rectal cancer (LARC), defined as T3/4 or any T with N+ disease. Our objective was to (1) determine the proportion of patients with LARC receiving TNT over time, (2) determine the most common method in which TNT is being delivered, and (3) determine what factors are associated with a greater likelihood of receiving TNT in the United States. Retrospective data was obtained from the National Cancer Database (NCDB) for patients diagnosed with rectal cancer between 2016 and 2020. Patients were excluded if they had M1 disease, T1-2 N0 disease, incomplete staging information, nonadenocarcinoma histology, received RT to a nonrectum site, or received a nondefinitive RT dose. Data were analyzed using linear regression, χ² test, and binary logistic regression. Of the 26,375 patients included, most patients were treated at an academic facility (94.6%). Five thousand three (19.0%) patients received TNT, and 21,372 (81.0%) patients did not receive TNT. The proportion of patients receiving TNT increased significantly over time, from 6.1% in 2016 to 34.6% in 2020 (slope = 7.36, 95% CI 4.58-10.15, R² = 0.96, P = .040). The most common TNT regimen was multiagent chemotherapy followed by long-course chemoradiation (73.2% of cases from 2016-2020). There was a significant increase in utilization of short-course RT as part of TNT from 2.8% in 2016 to 13.7% in 2020 (slope = 2.74, 95% CI 0.37-5.11, R² = 0.82, P = .035). Factors associated with a lower likelihood of TNT usage included age >65, female gender, Black race, and T3 N0 disease. TNT use in the United States has increased significantly from 2016-2020, with approximately 34.6% of patients with LARC receiving TNT in 2020. The observed trend appears to be in line with the recent National Comprehensive Cancer Network guidelines recommending TNT as the preferred approach.

Radiomics Approaches for the Prediction of Pathological Complete Response after Neoadjuvant Treatment in Locally Advanced Rectal Cancer: Ready for Prime Time?

In recent years, neoadjuvant therapy of locally advanced rectal cancer has seen tremendous modifications. Adding neoadjuvant chemotherapy before or after chemoradiotherapy significantly increases loco-regional disease-free survival, negative surgical margin rates, and complete response rates. The higher complete rate is particularly clinically meaningful given the possibility of organ preservation in this specific sub-population, without compromising overall survival. However, all locally advanced rectal cancer most likely does not benefit from total neoadjuvant therapy (TNT), but experiences higher toxicity rates. Diagnosis of complete response after neoadjuvant therapy is a real challenge, with a risk of false negatives and possible under-treatment. These new therapeutic approaches thus raise the need for better selection tools, enabling a personalized therapeutic approach for each patient. These tools mostly focus on the prediction of the pathological complete response given the clinical impact. In this article, we review the place of different biomarkers (clinical, biological, genomics, transcriptomics, proteomics, and radiomics) as well as their clinical implementation and discuss the most recent trends for future steps in prediction modeling in patients with locally advanced rectal cancer.

Effects of wound infection on prognosis after laparoscopic abdominoperineal resection of rectal cancer

Background

In two facilities in Chongqing, this research sought to retrospectively evaluate the effects of perineal wound infection on survival after laparoscopic abdominoperineal resection (LAPR) of rectal cancer.

Methods

To obtain clinical information on patients who underwent LAPR between January 2013 and December 2021, we performed a multicenter cohort study. A total of 473 patients were enrolled: 314 in the non-infection group and 159 in the group with perineal infection. The general data, perioperative conditions, and tumor outcomes between groups were analyzed. The infection rates, recurrence rates, and survival rates of the two centers were compared.

Results

The age, height, weight, body mass index (BMI), preoperative complications, preoperative treatment, and intraoperative conditions of patients in the LAPR infection group were not statistically different from those in the non-infection group. The percentage of men, typical postoperative hospital stay, length of initial postoperative therapy, and recurrence and metastasis rates were all considerably higher in the infection group than those in the non-infection group. Wound infection was an independent factor affecting tumor recurrence and metastasis after LAPR as well as an independent factor shortening patient survival time according to multivariate analysis. The incidence of wound infection, the rate of recurrence, and the rate of mortality did not vary significantly across sites.

Conclusion

Wound infection after LAPR increases the mean postoperative hospital stay, prolongs the time to first postoperative treatment, and decreases the disease-free survival (DFS) and overall survival (OS). Therefore, decreasing the rate of LAPR wound infection is expected to shorten the postoperative hospital stay and prolong the patient DFS and OS. Patients with postoperative infection may require intensive adjuvant therapy.

Total neoadjuvant treatment for MRI-stratified high-risk rectal cancer: a single-center, single-arm, prospective Phase II trial (PKUCH-R02)

Background

Induction chemotherapy combined with neoadjuvant chemoradiotherapy has been recommended for patients with high-risk, locally advanced rectal cancer. However, the benefit of more intensive total neoadjuvant treatment (TNT) is unknown. This study aimed to assess the safety and efficacy of induction chemotherapy combined with chemoradiotherapy and consolidation chemotherapy for magnetic resonance imaging-stratified high-risk rectal cancer.

Methods

This was a single-center, single-arm, prospective Phase II trial in Peking University Cancer Hospital (Beijing, China). Patients received three cycles of induction oxaliplatin and capecitabine (CapeOX) followed by chemoradiotherapy and two cycles of consolidation CapeOX. The primary end point was adverse event rate and the second primary end points were 3-year disease-free survival rate, completion of TNT, and pathological downstaging rate.

Results

Between August 2017 and August 2018, 68 rectal cancer patients with at least one high risk factor (cT3c/3d/T4a/T4b, cN2, mesorectal fascia involvement, or extramural venous invasion involvement) were enrolled. The overall compliance of receiving the entire treatment was 88.2% (60/68). All 68 patients received induction chemotherapy, 65 received chemoradiotherapy, and 61 received consolidation chemotherapy. The Grade 3-4 adverse event rate was 30.8% (21/68). Nine patients achieved clinical complete response and then watch and wait. Five patients (7.4%) developed distant metastasis during TNT and received palliative chemotherapy. Fifty patients underwent surgical resection. The complete response rate was 27.9%. After a median follow-up of 49.2 months, the overall 3-year disease-free survival rate was 69.7%.

Conclusions

For patients with high-risk rectal cancer, this TNT regimen can achieve favorable survival and complete response rates but with high toxicity. However, it is necessary to pay attention to the possibility of distant metastasis during the long treatment period.

Personalized total neoadjuvant therapy (pTNT) for advanced rectal cancer with tailored treatment sequencing based on clinical stage at presentation

BACKGROUND

This study aimed to assess short-term outcomes of a personalized total neoadjuvant treatment (pTNT) protocol, with treatment sequencing based on clinical stage at presentation.

METHODS

A multidisciplinary pTNT protocol was implemented across two metropolitan hospitals. This consists of two-schema based on clinical stage: patients with distant failure risk were offered induction chemotherapy before chemoradiation (nCRT), and patients with locoregional failure risk received nCRT followed by consolidation chemotherapy. Patients underwent surgical resection unless a complete clinical response (cCR) was achieved, in which case non-operative management (NOM) was offered. A prospective cohort analysis of all patients with rectal cancer who underwent pTNT with curative intent between Jan 2019 and Aug 2022 was performed.

RESULTS

Of 270 patients referred with rectal cancer, 102 received pTNT with curative intent and 79 have completed their treatment thus far. Thirty-three patients (41.8%) received induction chemotherapy and 46 (58.2%) received consolidation chemotherapy per protocol. The percentage of patients with EMVI, resectable M1 disease, cT4 disease, and positive lateral lymph nodes were 54.4%, 36.7%, 27.8% and 15.2%, respectively. Overall, 32 (40.5%) patients had cCR and 4 (5.1%) pCR, and 40 (50.6%) patients had non-operative management. Grade 3 toxicity was reported in 10.1% of patients and only three patients (3.8%) experienced Grade 4 chemotherapy-related toxicity, with no treatment related mortality.

CONCLUSION

Early results with a defined two-schema pTNT protocol are encouraging and suggest that tailoring sequencing to disease risk at presentation may represent the optimal balance between local and distant disease control, as well as treatment toxicity.

Cytokeratin 7 Expression and Mismatch Repair Status for Survival Prediction in Patients With Low Rectal Cancer After Neoadjuvant Therapy

BACKGROUND

More than half of the patients with locally advanced low rectal cancer exhibit no or minor response to nCRT. It is important to investigate the predictive and prognostic values of potential biomarkers in patients with locally advanced low rectal cancer receiving nCRT.

MATERIALS AND METHODS

This retrospective study included 162 patients with locally advanced low rectal cancer who underwent nCRT, followed by total mesorectal excision (TME) between 2016 and 2019. Cytokeratin 7 (CK7) expression and mismatch repair (MMR) status were determined by immunohistochemistry (IHC). Categorical variables were compared using the chi-square test. Overall survival (OS) and disease-free survival (DFS) curves were estimated using the Kaplan-Meier and Cox methods.

RESULTS

There were predominance significant differences in distance from anus margin (P < .0001) and circumferential extent of the tumor (P < .0001).CK7 positive expression was detected in 21 of the 162 patients (13%). The univariate and multivariate analysis revealed that patients whose tumors had CK7 positive expression had significantly shorter OS (HR = 3.878, P = .038; HR = 1.677, P = .035) and DFS (HR = 3.055, P = .027;HR = 3.569, P = .038) than those with CK7 negative expression. While patients with CK7 positive expression had a higher proportion of worse TRG compared with CK7 negative patients (P = .001). Patients with deficient mismatch repair (dMMR) just occupied a small proportion (8.6%), but there was still a close connection between the MMR status and recurrence after TME (P = .045). MMR status was an independent risk factor affecting the OS (HR = .307, P < .0001; HR = .123, P < .0001) and DFS (HR = .288, P < .0001; HR = .286, P < .0001) by univariate and multivariate analysis. But no significant difference in the proportion of TRG was observed between patients with dMMR and pMMR (P = .920).

CONCLUSIONS

The result confirms negative prognostic role of CK7-positive and dMMR statuses, which have potential predictive value for neoadjuvant chemoradiotherapy response. This provides opportunity to modify individualized treatment strategies for patients with different CK7 expression levels and dMMR statuses.

Total neoadjuvant treatment and PD-1/PD-L1 checkpoint inhibitor in locally advanced rectal cancer

For local advanced rectal cancer (LARC), total neoadjuvant treatment (TNT) has shown more complete response (CR), reduced risk of distant metastasis (DM) and increase of the sphincter preservation rate. Now it is the one and only recommendation for high-risk group of LARC according to National Comprehensive Cancer Network (NCCN) rectal cancer guideline, while it is also preferentially recommended for low-risk group of LARC. TNT is also beneficial for distant rectal cancer patients who have need for organ preservation. Even though the prognostic value of programmed cell death-ligand 1 (PD-L1) in the neoadjuvant chemoradiotherapy (NACRT) of LARC patients is undetermined yet, the combination of NACRT and programmed cell death-1 (PD-1)/PD-L1 antibodies seem bring new hope for mismatch repair proficient (pMMR)/microsatellite stable (MSS) LARC patients. Accumulating small sample sized studies have shown that combining NACRT with PD-1/PD-L1 antibody yield better short-term outcomes for pMMR/MSS LARC patients than historic data. However, ideal total dose and fractionation of radiotherapy remains one of unresolved issues in this combination setting. Thorough understanding the impact of radiotherapy on the tumor microenvironment and their interaction is needed for in-depth understanding and exquisite design of treatments combination model.

Outcomes of Locally Advanced Rectal Cancer Patients Treated with Total Neoadjuvant Treatment: A Meta-Anaysis of Randomized Controlled Trials

BACKGROUND & AIMS

Determining outcomes using the total neoadjuvant therapy (TNT) in patients with local advanced rectal cancer is important for stratifying patients according to expected outcomes in future studies in the era of treatment combination. The present meta-analysis estimated the pathological complete response, disease-free survival, and overall survival probabilities of rectal cancer patients and identified predictors of outcomes.

METHODS

Studies reporting pathological complete response rate and time-dependent outcomes (progression or death) after total neoadjuvant treatment of locally advanced rectal cancer (LARC) were identified in MEDLINE through January 2022. Three independent observers extracted data on patient populations and outcomes and combined the data using a distribution-free summary survival curve. The primary outcomes were actuarial probabilities of recurrence and survival.

RESULTS

Fourteen RCTs, including 18 TNT arms, met the inclusion criteria. The pooled estimate of pathological complete response (pCR) probability was 23.6%, with moderate heterogeneity between studies. The pooled estimates of actuarial disease-free survival rate were 70.6% at 3 years and 65.4% at 5 years. The pooled estimates of actuarial survival rates were 93% at 3 years and 81.6% at 5 years. In both these outcomes, heterogeneity between studies was highly significant.

CONCLUSION

This meta-analysis showed that Total Neoadjuvant Therapy is an optimal approach for LARC patients. The results provide a useful benchmark for future comparisons of the benefits of combinations of other drug families as target therapies or immunotherapies.

Total neoadjuvant therapy versus standard therapy in locally advanced rectal cancer: A systematic review and meta-analysis of 15 trials

Background

Neoadjuvant chemoradiotherapy (nCRT) before total mesorectal excision (TME) and followed systemic chemotherapy is widely accepted as the standard therapy for locally advanced rectal cancer (LARC). This meta-analysis was to evaluate the current evidence regarding nCRT in combination with induction or consolidation chemotherapy for rectal cancer in terms of oncological outcomes.

Methods

A systematic search of medical databases (PubMed, EMBASE and Cochrane Library) was conducted up to the end of July 1, 2021. This meta-analysis was performed to evaluate the efficacy of TNT in terms of pathological complete remission (pCR), nCRT or surgical complications, R0 resection, local recurrence, distant metastasis, disease-free survival (DFS) and overall survival (OS) in LARC.

Results

Eight nRCTs and 7 RCTs, including 3579 patients were included in the meta-analysis. The rate of pCR was significantly higher in the TNT group than in the nCRT group, (OR 1.85, 95% CI 1.39–2.46, p < 0.0001), DFS (HR 0.80, 95% CI 0.69–0.92, p = 0.001), OS (HR 0.75, 95% CI 0.62–0.89, p = 0.002), nCRT complications (OR 1.05, 95% CI 0.77–1.44, p = 0.75), surgical complications (OR 1.02, 95% CI 0.83–1.26, p = 0.83), local recurrence (OR 1.82, 95% CI 0.95–3.49, p = 0.07), distant metastasis (OR 0.77, 95% CI 0.58–1.03, p = 0.08) did not differ significantly between the TNT and nCRT groups.

Conclusion

TNT appears to have advantages over standard therapy for LARC in terms of pCR, R0 resection, DFS, and OS, with comparable nCRT and postoperative complications, and no increase in local recurrence and distant metastasis.

Understanding the Philosophy, Anatomy, and Surgery of the Extra-TME Plane of Locally Advanced and Locally Recurrent Rectal Cancer; Single Institution Experience with International Benchmarking

Pelvic exenteration surgery has become a widely accepted procedure for treatment of locally advanced (LARC) and locally recurrent rectal cancer (LRRC). However, there is still unwarranted variation in peri-operative management and subsequently oncological outcome after this procedure. In this article we will elaborate on the various reasons for the observed differences based on benchmarking results of our own data to the data from the PelvEx collaborative as well as findings from 2 other benchmarking studies. Our main observation was a significant difference in extent of resection between exenteration units, with our unit performing more complete soft tissue exenterations, sacrectomies and extended lateral compartment resections than most other units, resulting in a higher R0 rate and longer overall survival. Secondly, current literature shows there is a tendency to use more neoadjuvant treatment such as re-irradiation and total neoadjuvant treatment and perform less radical surgery. However, peri-operative chemotherapy or radiotherapy should not be a substitute for adequate radical surgery and an R0 resection remains the gold standard. Finally, we describe our experiences with standardizing our surgical approaches to the various compartments and the achieved oncological and functional outcomes.

Early and late radiation complications after application of preoperative radiation therapy in complex treatment of cancer recti

Objective. To study and assess the rates and degree of severity of early and late radiation complications in patients after application of preoperative radiation therapy in complex treatment of the patients, suffering cancer recti. Materials and methods. Analysis of the treatment results in 113 patients, suffering locally–advanced (сT3с–4N1–2M0) cancer recti, who have obtained preoperative oncotherapy in 2019–2022 yrs in the Department of Radiation Therapy of Zakarpattya Antitumoral Centre, was performed. Results. Most frequent early radiation affection was rectitis, which have occurred – in 86 (76,1%) patients of 113. Early radiation affections of the reproductive system organs were noted in 5 (4,4%) patients. Late radiation affections were registered in 9 (7,9%) patients, mostly frequent in the gut system – in 5 (4,4%) patients. Conclusion. Аnalysis of the complex treatment results, performed in 113 patients with cancer recti, have shown, that preoperative radiation therapy do not enhance the rate of occurrence of early radiation complications and hematological toxicity. The rate of early radiation affections was 76,1%, and of the late – 7,9%.

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

Background and Aim

The effectiveness of total neoadjuvant therapy (TNT) on patients with locally advanced rectal cancer (LARC) is controversy. This study aims to compare the prognostic value of TNT with standard neoadjuvant chemoradiotherapy (CRT) for LARC.

Methods

We searched databases (Embase [Ovid], Medline [Ovid], PubMed, Cochrane Library, and Web of Science) for articles published between January 1, 2000, and March 10, 2022. Studies on evaluating the effects of TNT and standard CRT on the prognosis of LARC were included. The primary outcomes were overall survival (OS) and disease-free survival (DFS).

Results

19 primary studies, involving 10 randomized controlled trials, 3 prospective studies and 6 retrospective studies, with data on 5,074 patients treated for LARC were included in the meta-analysis. Statistical analyses revealed that, compared with standard CRT, TNT significantly improved OS (hazard ratio [HR]=0.77, 95% confidence interval [CI]=0.65–0.90, I² = 30%, P = 0.17), DFS (HR = 0.85, 95% CI = 0.74–0.97, I² = 11%, P = 0.35), distant metastases-free survival (DMFS, HR = 0.76, 95% CI = 0.65–0.90, I² = 0%, P = 0.50), pathological complete response rate (pCR, OR = 1.89, 95% CI = 1.61–2.22, I² = 0%, P = 0.47), and R0 resection rate (OR = 1.33, 95% CI = 1.07–1.67, I² = 16%, P = 0.28), but local recurrence-free survival (LRFS, HR = 1.12, 95% CI = 0.90–1.39, I² = 4%, P = 0.37).

Conclusions

Comprehensive literature research shows that TNT showed excellent short-term efficacy in terms of pCR and R0 resection rate while also improved the long-term outcomes of OS, DFS and DMFS, might become a new standard of treatment in patients with LARC. Even so, more studies and longer follow-up were still warranted.

Safety and feasibility of neoadjuvant chemotherapy as a surgical bridge for acute left-sided malignant colorectal obstruction: a retrospective study

BACKGROUND

For colorectal cancer, preoperative (neoadjuvant) chemotherapy is more effective than postoperative chemotherapy because it not only eradicates micrometastases more effectively but also reduces the risk of incomplete intraoperative resection and tumor cell shedding. For the treatment of acute left-sided malignant colorectal obstruction, colorectal stents as well as stoma are being used to relieve the obstructive colorectal cancer, and as a bridge to surgery, allowing easy mobilization and resection of the colon. Neoadjuvant chemotherapy combined with self-expandable metal stents (SEMS) or neoadjuvant chemotherapy combined with decompressing stoma (DS) can be used as a bridge to elective surgery (BTS) as an alternative to emergency surgery in patients with acute left-sided malignant colorectal obstruction, but its benefit is uncertain. The purpose of this study was to evaluate the safety and feasibility of neoadjuvant chemotherapy as a bridge to surgery in the treatment of acute left-sided malignant colorectal obstruction.

METHODS

Data from patients who were admitted with acute left-sided malignant colorectal obstruction between January 2012 and December 2020 were retrospectively reviewed, and patients with gastrointestinal perforation or peritonitis were excluded. We performed one-to-two propensity score matching to compare the stoma requirement, postoperative complications, and other short-term oncological outcomes between the neoadjuvant chemotherapy group and surgery group.

RESULTS

There were no differences in intraoperative blood loss, operative time, one-year postoperative mortality, and postoperative tumor markers between the two groups. The 1-year recurrence-free survival (RFS) rates of neoadjuvant chemotherapy group and surgery group were 96.8 and 91.3% (p = 0.562). The neoadjuvant chemotherapy group was able to reduce stoma rate 1 year after surgery (p = 0.047). Besides, the neoadjuvant group significantly reduced postoperative bowel function time (p < 0.001), postoperative hospital stay (p < 0.001), total hospital stay (p = 0.002), postoperative complications (p = 0.017), reduction in need to stay in the intensive care unit (ICU) (p = 0.042).

CONCLUSIONS

Neoadjuvant chemotherapy as a bridge to elective surgery in patients with acute left-sided malignant colorectal obstruction is safe and has many advantages. Prospective multicenter studies with large samples are needed to further evaluate the feasibility of neoadjuvant chemotherapy.

Microsatellite instability in rectal cancer: what does it mean? A study of two randomized trials and a systematic review of the literature

Currently, compelling evidence illustrates the significance of determining microsatellite instability (MSI) in colorectal cancer (CRC). The association of MSI with proximal CRC is well established, however, its implications in patients with rectal cancer remain undefined. We therefore aimed to determine the role of MSI with respect to incidence and outcome in patients with rectal cancer, by the examination of patients from two prospective phase III trials: TME trial and PROCTOR-SCRIPT trial (n=1250). No differences in terms of overall survival (HR 1.00, 95%CI 0.69-1.47) and disease-free survival (HR 1.00, 95%CI 0.68-1.45) were observed in patients with MSI compared to microsatellite stable (MSS) rectal cancer. In addition, we performed a literature review to evaluate the overall prevalence, the effect on survival and the response to neo-adjuvant treatment in patients with MSI rectal cancer compared with MSS rectal cancer. The total number of MSI cases in the included studies (including our own) was 1220 (out of 16526 rectal cancer patients), with an overall prevalence of 6.7% (SE 1.19%). Both for overall survival as for disease-free survival there was no impact of MSI status on prognosis (HR 1.00, 95%CI 0.77-1.29 and HR 0.86, 95% CI 0.60-1.22, respectively). The risk ratio for downstaging and pCR showed also no impact of MSI status (RR 1.15, 95% CI 0.86-1.55 and RR 0.81, 95% CI 0.54-1.22 respectively). In conclusion, rectal cancer patients with MSI form a distinct and rare subcategory, however, there is no prognostic effect of MSI in rectal cancer patients.

Total neoadjuvant therapy for the treatment of locally advanced rectal cancer: a systematic minireview

Colorectal carcinoma is the second leading cause of cancer-related deaths, and indeed, rectal cancer accounting for approximately one third of newly diagnosed patients. Gold standard in the treatment of rectal cancer is a multimodality approach, aiming at a good control of the local disease. Distant recurrences are the major cause of mortality. Currently, Locally Advanced Rectal Cancer (LARC) patients undergo a combined treatment of chemotherapy and radiotherapy, followed by surgery. Eventually, more chemotherapy, namely adjuvant chemotherapy (aCT), may be necessary. Total Neoadjuvant Therapy (TNT) is an emerging approach aimed to reduce distant metastases and improve local control. Several ongoing studies are analyzing whether this new approach could improve oncological outcomes. Published results were encouraging, but the heterogeneity of protocols in use, makes the comparison and interpretation of data rather complex. One of the major concerns regarding TNT administration is related to its effect on larger and more advanced cancers that might not undergo similar down-staging as smaller, early-stage tumors. This minireview, based on a systematic literature search of randomized clinical trials and meta-analysis, summarizes current knowledge on TNT. The aim was to confirm or refute whether or not current practice of TNT is based on relevant evidence, to establish the quality of that evidence, and to address any uncertainty or variation in practice that may be occurring. A tentative grouping of general study characteristics, clinical features and treatments characteristics has been undertaken to evaluate if the reported studies are sufficiently homogeneous in terms of subjects involved, interventions, and outcomes to provide a meaningful idea of which patients are more likely to gain from this treatment.

Oncological outcomes of multimodality treatment for patients undergoing surgery for locally recurrent rectal cancer: A systematic review

BACKGROUND

There are several strategies in the management of locally recurrent rectal cancer (LRRC) with the optimum treatment yet to be established. This systematic review aims to compare oncological outcomes in patients undergoing surgery for LRRC who underwent neoadjuvant radiotherapy or chemoradiotherapy (CRT), adjuvant CRT, surgery only or surgery and intraoperative radiotherapy (IORT).

METHODS

A literature search of MEDLINE, EMBASE and CINAHL was performed for studies that reported data on oncological outcomes for the different treatment modalities in patients with LRRC from January 1990 to January 2022. Weighted means were calculated for the following outcomes: postoperative resection status, local control, and overall survival at 3 and 5 years.

RESULTS

Fifteen studies of 974 patients were included and they received the following treatment: 346 neoadjuvant radiotherapy, 279 neoadjuvant CRT, 136 adjuvant CRT, 189 surgery only, and 24 surgery and IORT. The highest proportion of R0 resection was found in the neoadjuvant CRT group followed by neoadjuvant radiotherapy and adjuvant CRT groups (64.07% vs 52.46% vs 47.0% respectively). The neoadjuvant CRT group had the highest mean 5-year local control rate (49.50%) followed by neoadjuvant radiotherapy (22.0%). Regarding the 5-year overall survival rate, the neoadjuvant CRT group had the highest mean of 34.92%, followed by surgery only (29.74%), neoadjuvant radiotherapy (28.94%) and adjuvant CRT (20.67%).

CONCLUSIONS

The findings of this systematic review suggest that neoadjuvant CRT followed by surgery can lead to improved resection status, long-term disease control and survival in the management of LRRC. However, treatment strategies in LRRC are complex and further comparisons, particularly taking into account previous treatments for the primary rectal cancer, are required.

A phase Ib feasibility trial of response adapted neoadjuvant therapy in gastric cancer (RANT-GC)

Current guidelines recommend neoadjuvant (NAC) and/or adjuvant chemotherapy for locally advanced gastric cancers (LAGCs). However, the choice and duration of NAC regimen is standardized, rather than personalized to biologic response, despite the availability of several different classes of agents for the treatment of gastric cancer (GC). The current trial will use a tumor-informed ctDNA assay (Signatera^™) and monitor response to NAC. Based on ctDNA kinetics, the treatment regimen is modified. This is a prospective single center, single arm, open label study in clinical stage IB-III GC. ctDNA is measured at baseline and repeated every 8 weeks. Imaging is performed at the same intervals. The primary endpoint is the feasibility of this approach, defined as percentage of patients completing gastrectomy.

The Long and the Short of it: the Role of Short-course Radiotherapy in the Neoadjuvant Management of Rectal Cancer

Total mesorectal excision is the cornerstone of treatment for rectal cancer. Multiple randomised trials have shown a reduction in local recurrence rates with the addition of preoperative radiotherapy, either as a 1-week hypofractionated short-course (SCRT) or a conventionally fractionated long-course (LCRT) schedule with concurrent chemotherapy. There is also increasing interest in the addition of neoadjuvant chemotherapy to radiotherapy with the aim of improving disease-free survival. The relative use of SCRT and LCRT varies considerably across the world. This is reflected in, and is probably driven in part by, disparity between international guideline recommendations. In addition, different approaches to treatment may exist both between and within countries, with variation related to patient, disease and treatment centre and financial factors. In this review, we will specifically focus on the use of SCRT for the treatment of rectal cancer. We will discuss the literature base and current guidelines, highlighting the challenges and controversies in clinical application of this evidence. We will also discuss potential future applications of SCRT, including its role in optimisation and intensification of treatment for rectal cancer.

Right colon, left colon, and rectal cancer have different oncologic and quality of life outcomes

PURPOSE

Colorectal cancer patients are commonly considered a single entity in outcomes studies. This is particularly true for quality of life (QOL) studies. This study aims to compare oncologic and QOL outcomes between right colon, left colon, and rectal cancer in patients operated on in a single high-volume institution.

METHODS

A prospectively maintained database was queried to identify patients with pathological stages I-III colorectal adenocarcinoma electively operated on with curative intent between 2000 and 2010. Patient characteristics, perioperative and oncologic outcomes, and QOL were compared according to cancer location.

RESULTS

Two-thousand sixty-five (606 right colon cancer [RCC], 366 left colon cancer [LCC], and 1093 rectal cancer [RC]) patients met the inclusion criteria. LCC had better overall survival (OS) and disease-free survival (DFS) in the non-adjusted analysis (p < 0.001) and better OS in multivariate analysis adjusted by age, gender, ASA, chemotherapy, and pathological stage (p = 0.024). Although RCC had worse OS and DFS in non-adjusted survival analysis than LCC and RC, when adjusted for the factors above, RCC had better survival outcomes than RC, but not LCC. COX regression analysis showed age (p < 0.001), gender (p = 0.016), ASA (p < 0.001), pathological stage (p < 0.001), adjuvant chemotherapy (p = 0.043), and cancer location (p = 0.024) were independently associated with OS. Age (p < 0.001), gender (p = 0.030), ASA (p = 0.004), and pathological stage (p < 0.001) were independently associated with DFS. Patients with RC reported more sexual dysfunction and work restrictions than colon cancers (p = 0.015 and p < 0.001, respectively).

CONCLUSION

In an adjusted multivariate analysis, colon cancers demonstrated better survival outcomes when compared to rectal cancers.