Improved sphincter preservation in low rectal cancer with high-dose preoperative radiotherapy: the lyon R96-02 randomized trial

Low energy contact X-ray brachytherapy for treatment of rectal cancer: a health technology appraisal by Health Technology Wales

AIM

Health Technology Wales sought to evaluate the clinical and cost-effectiveness of contact X-ray brachytherapy (CXB) for early-stage rectal cancer.

METHODS

Relevant studies were identified through systematic searches of MEDLINE, Embase, Cochrane Library and Scopus. A cost-utility model was developed to estimate the cost-effectiveness of CXB in National Health Service Wales, using results of the Organ Preservation in Early Rectal Adenocarcinoma (OPERA) trial. Patient perspectives were obtained through the Papillon Patient Support group and All-Wales Cancer Network.

RESULTS

The OPERA randomized controlled trial showed that CXB improved complete response and organ preservation rates compared with external-beam boost for people with T2-3b, N0-1, M0 rectal cancer who are fit for surgery. Managing more of this population non-operatively after CXB was estimated to provide 0.2 quality-adjusted life years at an additional cost of £887 per person. CXB was cost effective compared with external-beam boost at a cost of £4463 per quality-adjusted life year gained. This conclusion did not change in scenario analysis and CXB was cost effective in 91% of probabilistic sensitivity analyses. Patients valued receiving clear information on all available options to support their individual treatment choices. The detrimental impact of a stoma on quality of life led some patients to reject the idea that surgery was their only option.

CONCLUSION

This evidence review and cost-utility analysis indicates that CXB is likely to be clinically and cost effective, as part of a watch and wait strategy for adults fit for surgery. Wider access to CXB is supported by patient testimonies.

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

The safety and efficacy of total mesorectal excision (TME) surgery following dose-escalation: Surgical outcomes from the organ preservation in early rectal adenocarcinoma (OPERA) trial, a European multicentre phase 3 randomised trial (NCT02505750)

AIM

Nonsurgical treatment with chemoradiotherapy for rectal cancer is gaining interest as it avoids total mesorectal excision (TME) surgery and stoma. The OPERA trial aims to evaluate whether dose escalation with contact X-ray brachytherapy (CXB) boost improves organ preservation compared to external beam radiotherapy (EBRT) boost. It has been suggested that dose escalation adversely affects surgical outcomes and therefore we report outcomes following TME in OPERA at 36 months.

METHODS

OPERA is a European multicentre phase 3 trial (NCT02505750) which randomises patients with cT2-3a-b, cN0-1, M0 to EBCRT (45 Gy in 25 fractions over 5 weeks with oral capecitabine 825 mg/m2 ) followed by EBRT boost (9 Gy in 5 fractions over 5 days) versus EBCRT followed by CXB boost (90 Gy in 3 fractions over 4 weeks). Patients were assessed at 14, 20 and 24 weeks from the start of treatment. Watch and wait management was adopted for patients who achieved a clinical complete response (cCR) at 24 weeks following treatment. Either local excision (LE) or TME surgery was offered for residual disease or local regrowth, according to patient and surgeon preference. Surgical morbidity and mortality were recorded prospectively.

RESULTS

Between July 2015 and June 2020, 148 patients were randomised of which 141 were evaluable in March 2022. At median follow-up of 38.2 months (range: 34.2-42.5), surgery was performed for 66 (47%) patients. A total of 27 (20%) patients had local excision and 39 (29%) had TME surgery, 22/39 (56%) underwent anterior resection and 17/39 (44%) underwent abdominoperineal excision of the rectum. The R0 resection rate was 87%. There were no deaths, and six patients (15%) had Clavien-Dindo IIIb complications. Whilst there was a statistically significant decrease in the TME rate following CXB boost (HR 0.38, 95% CI: 0.19-0.74, p = 0.00419) there was no difference in surgical outcomes between patients who received EBRT and CXB boost.

CONCLUSION

Dose escalation can facilitate nonsurgical treatment for cT2-3 rectal cancer patients who are fit but wish to avoid TME surgery and stoma. If TME surgery is required, then it can be performed safely and effectively.

Efficacy of hypofractionated preoperative chemoradiotherapy in rectal cancer

The efficacy and toxicity of hypofractionated preoperative chemoradiotherapy (HPCRT) combined with oral capecitabine was evaluated in patients with rectal cancer. HPCRT was delivered by intensity-modulated radiotherapy of either 33 Gy to the whole pelvis or 35 Gy in 10 fractions to the primary tumor and 33 Gy to the surrounding pelvis. Surgery was performed 4-8 weeks after HPCRT completion. Oral capecitabine was administered concurrently. A total of 76 patients were eligible for this study, and patient numbers in clinical stages I, II, III and IVA were 5, 29, 36 and 6, respectively. Tumor response, toxicity and survival were analyzed. A total of 9/76 patients (11.8%) achieved a pathological complete response. Sphincter preservation was achieved in 23/32 (71.9%) and 44/44 (100%) of patients with a distal extent from the anal verge of ≤5 and >5 cm, respectively. A total of 28/76 patients (36.8%) achieved tumor-downstaging and 25/76 (32.9%) achieved nodal (N)-downstaging. The 5-year disease-free survival (DFS) and overall survival rates were 76.5% and 90.6%, respectively. In the multivariate analysis for DFS, pathological N stage and lymphovascular space invasion were notable prognostic factors. A total of 6 patients in stage IVA underwent salvage treatments for lung or liver metastasis after HPCRT completion, and all 6 were alive at the last follow-up. Only 4 patients experienced grade 3 postoperative complications. No grade 4 toxicities were observed. HPCRT of 33 or 35 Gy in 10 fractions showed similar results to those of long-course fractionation. This fractionation scheme could be beneficial for patients with early stage disease, locally advanced rectal cancer, simultaneous distant metastasis requiring early intervention or for patients who wish to avoid multiple hospital visits.

Neoadjuvant chemoradiotherapy with radiation dose escalation with contact x-ray brachytherapy boost or external beam radiotherapy boost for organ preservation in early cT2-cT3 rectal adenocarcinoma (OPERA): a phase 3, randomised controlled trial

BACKGROUND

Organ preservation after reaching clinical complete response on neoadjuvant therapy is gaining interest for rectal cancers, although the role of radiation dose escalation is still not known. We aimed to determine whether a contact x-ray brachytherapy boost, following or preceding neoadjuvant chemoradiotherapy, increases the probability of 3-year organ preservation for patients with early rectal cancers.

METHODS

OPERA was a multicentre, open-label, phase 3 randomised controlled trial done at 17 cancer centres that included operable patients, aged 18 years or older, with cT2, cT3a, or cT3b adenocarcinoma of low-mid rectum, tumours of less than 5 cm in diameter, and cN0 or cN1 smaller than 8 mm. All patients received neoadjuvant chemoradiotherapy and 45 Gy external beam radiotherapy in 25 fractions over 5 weeks with concurrent oral capecitabine (825 mg/m² twice a day). Patients were randomly assigned (1:1) to receive a boost of external beam radiotherapy at 9 Gy in five fractions (group A) or a boost with contact x-ray brachytherapy (90 Gy in three fractions; group B). Randomisation was done centrally using an independent web-based system and stratified by trial centre, tumour classification (cT2 vs cT3a or cT3b), tumour distance from rectum (<6 cm from anal verge vs ≥6 cm), and tumour diameter (<3 cm vs ≥3 cm). Treatment in group B was stratified by tumour diameter, with the contact x-ray brachytherapy boost given before neoadjuvant chemoradiotherapy in patients with tumours smaller than 3 cm. The primary outcome was organ preservation at 3 years, analysed in the modified intention-to-treat population. This study was registered with ClinicalTrials.gov, NCT02505750, and is ongoing.

FINDINGS

Between June 14, 2015, and June 26, 2020, 148 patients were assessed for eligibility and were randomly assigned to group A (n=74) or group B (n=74). Seven patients withdrew their consent (five in group A and two in group B). 141 patients were included in the primary efficacy analysis, including 69 assigned to group A (29 with tumours <3 cm in diameter and 40 with tumours ≥3 cm) and 72 assigned to group B (32 with tumours <3 cm and 40 with tumours ≥3 cm). After a median follow-up of 38·2 months (IQR 34·2-42·5), the 3-year organ preservation rate was 59% (95% CI 48-72) in group A versus 81% (72-91) in group B (hazard ratio [HR] 0·36, 95% CI 0·19-0·70; p=0·0026). For patients with tumours less than 3 cm in diameter, 3-year organ preservation rates were 63% (95% CI 47-84) in group A versus 97% (91-100) in group B (HR 0·07, 95% CI 0·01-0·57; p=0·012). For patients with tumours of 3 cm or larger, 3-year organ preservation rates were 55% (95% CI 41-74) in group A versus 68% (54-85) in group B (HR 0·54, 95% CI 0·26-1·10; p=0·11). 21 (30%) patients in group A and 30 (42%) in group B had an early grade 2-3 adverse event (p=1·0). The most common early grade 2-3 adverse events were proctitis (four [6%] in group A, nine [13%] in group B) and radiation dermatitis (seven [10%] in group A, two [3%] in group B). The main late side-effect was grade 1-2 rectal bleeding due to telangiectasia, which was more frequent in group B (37 [63%] of 59) than in group A (five [12%] of 43; p<0·0001) and subsided after 3 years.

INTERPRETATION

Neoadjuvant chemoradiotherapy with a contact x-ray brachytherapy boost significantly improved the 3-year organ preservation rate, particularly for patients with tumours smaller than 3 cm who were treated with contact x-ray brachytherapy first, compared with neoadjuvant chemoradiotherapy with a boost via external beam radiotherapy. This approach could be discussed and offered to operable patients with early cT2-cT3 disease who are keen to avoid surgery and seek organ preservation.

FUNDING

The French Programme Hospitalier de Recherche Cinique.

Watch-and-Wait is an Option in Rectal Cancer Patients: From Controversy to Common Clinical Practice

Overview of the introduction of organ preservation in rectal cancer patients and future challenges.

Organ Preservation in Rectal Cancer: An Overview of the Dutch Perspective and Recent Developments

Although current guidelines on rectal cancer treatment often recommend rectal resection with or without neoadjuvant (chemo)radiotherapy, there is growing interest in organ-preserving treatment approaches among patients and clinicians in the Netherlands. Currently, multiple ongoing studies are investigating the value of different non-operative treatment modalities to improve tumour response rates and increase the chance of successful organ preservation. Papillon contact X-ray brachytherapy is a promising treatment modality to improve the chance of organ preservation, which seems especially relevant for elderly and frail patients unable or refusing to undergo total mesorectal excision surgery. The elderly and frail patient with rectal cancer poses a significant challenge and warrants a thorough multidisciplinary approach to provide the most optimal organ-preserving treatment. In this overview, an insight into the Dutch perspectives and developments within the field of organ preservation and the set-up of a Papillon facility to complete the spectrum of organ-preserving treatment options in a tertiary referral centre for rectal cancer treatment has been provided.

Radiotherapy dose escalation using endorectal brachytherapy in elderly and frail patients with rectal cancer unsuitable for surgery: Lessons from studies in fit patients and future perspectives

Epidemiological data indicate that more than 50 % of patients with newly-diagnosed rectal cancer are older than 70 years, with rising numbers expected over the next decades. Treatment decision-making is challenging in elderly and frail patients with rectal cancer, whereas standardized treatment guidelines for this patient cohort are lacking. Elderly and frail rectal cancer patients are often considered by surgeons as unfit to undergo radical surgery as the risk of surgical complications and postoperative mortality rises with increasing age and comorbidity. Furthermore, these patients often receive no treatment at all, resulting in local and/or systemic disease progression with associated symptoms and impaired quality of life (QoL). Recent data from randomized trials in young fit patients with early stage rectal cancer indicate that RT dose escalation can be safely delivered using external beam (chemo)radiotherapy (EBRT) followed by endoluminal radiotherapeutic modalities, such as contact X-ray brachytherapy (CXB) or high-dose rate endorectal brachytherapy (HDR-BT). However, prospective studies testing this therapeutic concept in elderly and frail patients remain limited. Here, we review the current evidence in the epidemiology and the management of elderly and frail patients with rectal cancer. We summarize the potential of RT dose escalation to achieve long-term local control of the primary tumour, prevent disease-related morbidity, improve QoL and even organ preservation. Future perspectives and open questions will be discussed as well.

Correlation between T stage and lymph node metastasis in rectal cancer treated with preoperative chemoradiotherapy

Background:

Depth of tumor is a risk factor for lymph node metastasis in rectal cancer, but impact of yield pathologic T (ypT) stage on lymph node involvement in rectal cancer remains unclear. The aim of this study was to evaluate the correlation between ypT stage and lymph node metastasis.

Methods:

From January 2010 to December 2015, 602 patients who were diagnosed with rectal cancer and treated with neoadjuvant chemoradiotherapy (CRT) followed by radical operation were reviewed retrospectively. The correlations between ypT stage and lymph node status and survival were evaluated.

Results:

On pathology, 179 (29.7%) patients exhibited regional lymph node metastasis. Lymph node metastasis was seen in 8.5% of ypT0 patients, 20% of ypT1, 18.4% of ypT2, 47.5% of ypT3, and 27.3% of ypT4. Positive lymph node metastasis was correlated with ypT stage. In addition, the difference of lymph node metastasis in ypT stage subgroups was statistically significant (p < 0.001). Five-year disease-free survival was significantly different in the ypT stage subgroups (88.7% versus 86.7% versus 82.6% versus 64.7% versus 72.7%, p < 0.001), as was 5-year overall survival (96.2% versus 90.0% versus 95.8% versus 80.0% versus 90.9%, p < 0.001).

Conclusion:

YpT stage is associated with lymph node metastasis in rectal cancer treated with neoadjuvant CRT and radical operation, and ypT0 patients exhibited an 8.5% lymph node metastasis rate. Therefore, the decision for local excision or the watch-and-wait strategy for rectal cancer treated with neoadjuvant CRT and predicted to show a pathologic complete response should be considered with caution.

MORPHEUS Phase II–III Study: A Pre-Planned Interim Safety Analysis and Preliminary Results

Background: We explored image-guided adaptive endorectal brachytherapy patients electing non-operative management for rectal cancer. We present the first pre-planned interim analysis. Methods: In this open-label phase II–III randomized study, patients with operable cT2-3ab N0 M0 rectal cancer received 45 Gy in 25 fractions of pelvic external beam radiotherapy (EBRT) with 5-FU/Capecitabine. They were randomized 1:1 to receive either an EBRT boost of 9 Gy in 5 fractions (Arm A) or three weekly adaptive brachytherapy (IGAEBT) boosts totaling 30 Gy (Arm B). Patient characteristics and toxicity are presented using descriptive analyses; TME-free survival between arms with the intention to treat the population is explored using the Kaplan–Meier method. Results: A total of 40 patients were in this analysis. Baseline characteristics were balanced; acute toxicities were similar. Complete clinical response (cCR) was 50% (n = 10/20) in Arm A and 90% in Arm B (n = 18/20). Median follow-up was 1.3 years; 2-year TME-free survival was 38.6% (95% CI: 16.5–60.6%) in the EBRT arm and 76.6% (95% CI: 56.1–97.1%) in the IGAEBT arm. Conclusions: Radiation intensification with IGAEBT is feasible. This interim analysis suggests an improvement in TME-free survival when comparing IGAEBT with EBRT, pending confirmation upon completion of this trial.

A Multidisciplinary Approach for the Personalised Non-Operative Management of Elderly and Frail Rectal Cancer Patients Unable to Undergo TME Surgery

Despite it being the optimal curative approach, elderly and frail rectal cancer patients may not be able to undergo a total mesorectal excision. Frequently, no treatment is offered at all and the natural course of the disease is allowed to unfold. These patients are at risk for developing debilitating symptoms that impair quality of life and require palliative treatment. Recent advancements in non-operative treatment modalities have enhanced the toolbox of alternative treatment strategies in patients unable to undergo surgery. Therefore, a proposed strategy is to aim for the maximal non-operative treatment, in an effort to avoid the onset of debilitating symptoms, improve quality of life, and prolong survival. The complexity of treating elderly and frail patients requires a patient-centred approach to personalise treatment. The main challenge is to optimise the balance between local control of disease, patient preferences, and the burden of treatment. A comprehensive geriatric assessment is a crucial element within the multidisciplinary dialogue. Since limited knowledge is available on the optimal non-operative treatment strategy, these patients should be treated by dedicated multidisciplinary rectal cancer experts with special interest in the elderly and frail. The aim of this narrative review was to discuss a multidisciplinary patient-centred treatment approach and provide a practical suggestion of a successfully implemented clinical care pathway.

Efficacy and Safety of Preoperative Radiotherapy Versus Chemoradiotherapy in Advanced Rectal Cancer: A Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This meta-analysis was conducted to evaluate the safety and efficacy of preoperative radiotherapy (RT) combined with surgery and preoperative chemoradiotherapy (CRT) combined with surgery for locally advanced rectal cancer.

METHODS

PubMed, EMBASE and Cochrane Library were searched to collect published randomized controlled trials of preoperative radiotherapy or preoperative CRT combined with surgery for the treatment of locally advanced rectal cancer. Studies were screened according to inclusion and exclusion criteria, and quality was evaluated; RevMan 5.3 software was used for meta-analysis.

RESULTS

In total, 7 related studies involving 3100 patients with locally advanced rectal cancer were evaluated. The pathological complete response rate, negative lymph node rate, R0 resection rate, and incidence of grade III/IV adverse reactions were lower in the RT group than in the CRT group. In the absence of postoperative chemotherapy, the 5-year local recurrence rate of RT was higher than that of CRT, but there was no significant difference between the groups among those who underwent postoperative chemotherapy. Moreover, there was no significant difference between the groups with regard to the 5-year survival rate, anal-preserving rate, or incidence of anastomotic leakage.

CONCLUSION

Preoperative CRT is better than preoperative RT for the treatment of advanced rectal cancer, though the adverse reaction rate is higher.

Targeted Radiotherapy Using Contact X-ray Brachytherapy 50 kV

Rectal adenocarcinoma is a quite radioresistant tumor. In order to achieve non-operative management (NOM) radiotherapy plays a major role. Targeted radiotherapy aiming at high precision 3D radiotherapy uses stereotactic image-guided external beam radiotherapy machines. To further safely increase the tumor dose, endocavitary brachytherapy (ECB) is an original approach. There are two different ways to perform such an ECB: contact X-ray brachytherapy (CXB) using a 50 kV X-ray generator with an X-ray tube positioned under eye guidance into the rectal cavity and high-dose-rate brachytherapy (HDRB) using iridium-192 sources positioned into the rectal cavity under image guidance. This study focused on CXB. CXB uses a small mobile generator that produces 50 kV X-rays with limited penetration. This technique is well adapted to accessible tumors of limited size and especially needs a high dose rate (≥15 Gy/minutes) for rectal tumors. It is performed on an ambulatory basis. A total dose between 80−110 Gy is delivered in 3−4 fractions over 3 to 6 weeks into a small volume (5 cm3). CXB was pioneered in the 1970s by Papillon using the Philips RT 50TM. Since 2009, the Papillon P50TM has been used in 11 institutions in Europe. The OPERA Phase III trial tested the hypothesis that a CXB boost (90 Gy/3 fr) compared to an EBRT boost (9 Gy/5 fr) for T2−T3 ab < 5 cm and N0−N1 < 8 mm will increase the 3-year organ preservation (OP) rate when combined with 45 Gy/5 weeks with concomitant capecitabine. Out of more than 300 patients with tumors < 3 cm (1962−1992), Papillon reported a long-term local control close to 85%. Similar results were published in Europe and USA at that time. The Lyon R96-2 Phase III trial (2004) demonstrated that, when combined with preoperative EBRT, a CXB boost (90 Gy/3 fr) significantly increased the rate of clinical complete response (cCR) and sphincter preservation, with some patients having OP at 10 years. With more than 2000 patients treated in Europe (2010−2020) using the Papillon 50TM, organ preservation appears possible in close to 80% of cases in selected early T2−T3. The OPERA trial closed after 141 inclusions (2015−2020) after an independent data monitoring committee recommendation because of promising results. At the 2-year follow-up (blinded data), the rate of cCR and OP were 77% and 72%, respectively, for the 141 tumors, and for T < 3 cm (61 pts), they were 86% and 85%, respectively, with good bowel function. The final results should be available in 2022. Organ preservation using NOM appears to be a promising approach for rectal cancer. A CXB boost with chemoradiotherapy in selected early T2−T3 could become an attractive option to achieve a planned OP. This approach should be proposed to well-informed patients after discussion in an MDT.

Structured and shared MRI staging lexicon and report of rectal cancer: A consensus proposal by the French Radiology Group (GRERCAR) and Surgical Group (GRECCAR) for rectal cancer

PURPOSE

To develop French guidelines by experts to standardize data acquisition, image interpretation, and reporting in rectal cancer staging with magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Evidence-based data and opinions of experts of GRERCAR (Groupe de REcherche en Radiologie sur le CAncer du Rectum [i.e., Rectal Cancer Imaging Research Group]) and GRECCAR (Groupe de REcherche en Chirurgie sur le CAncer du Rectum [i.e., Rectal Cancer Surgery Research Group]) were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of reporting template and protocol for data acquisition were collected; responses were analyzed and classified as "Recommended" versus "Not recommended" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts).

RESULTS

Consensus regarding patient preparation, MRI sequences, staging and reporting was attained using the RAND-UCLA Appropriateness Method. A consensus was reached for each reporting template item among the experts. Tailored MRI protocol and standardized report were proposed.

CONCLUSION

These consensus recommendations should be used as a guide for rectal cancer staging with MRI.

Propensity score analysis of radical proctectomy versus organ preservation using contact X-ray brachytherapy for rectal cancer

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Key objective: the goal provides data to evaluate the oncological risk of performing a planned- conservative strategy in selected patients presenting early T2-T3 rectal adenocarcinoma.

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Knowledge generated: This propensity score analysis on 72 patients, comparing neoadjuvant chemoradiotherapy followed by radical surgery with planned organ preservation using combined chemoradiotherapy and contact X-ray brachytherapy boost, showed no detrimental oncological safety results after 5 year follow-up.

•

Relevance: This study supplies additional arguments in favor of organ preservation for selected early rectal T2-T3.

Introduction

Radical proctectomy (RP-TME) with neo adjuvant chemoradiotherapy (nCRT) remains the standard treatment for T2-T3 rectal cancer. Organ preservation (OP) using CRT and a “watch and wait” strategy (W&W) is a field of research. Planned organ preservation can be proposed for early T1-T3 using contact X-ray brachytherapy (CXB). We compared the oncological outcomes of both approaches using a propensity score matched-cohort analysis.

Material and methods

For comparative analyses between patients with nCRT + RP-TME and patients with CXB + CRT, propensity scores were calculated with logistic regression and multiple imputations for missing data. The variables included in the propensity score model were PS status, T-N stage and rectal circumference extension. Patients were matched 1:1 using the nearest neighbor method with a 0.1 caliper restriction. The 5-year Cancer Specific survival was the primary end point.

Results

The Accord 12 phase III trial included 584 patients who treated with nCRT + RP-TME. The CXB cohort included 71 patients with a planned OP. To select OP patient candidate, T4, tumor with extension >66% circumference were eliminated and only patients treated with CXB + CRT were analyzed in the CXB cohort resulting in a total of 374 patients. A one to one paired cohort with 36 patients in each group was derived. These two cohorts were well matched for all confounding factors except for age. The 5-year cancer specific rate showed no significant difference between the two groups (89% in Accord 12 vs 82% in CXB; p = 0.84). At 5 years, rate of metastasis (15% vs 22%, p = 0.54) showed no significant difference. In the CXB group 33/36 patients preserved their rectum.

Conclusion

The organ preservation strategy using CXB boost yielded a 5-year cancer specific survival rate similar to patients treated with RP-TME. In selected early T2-3 rectal adenocarcinoma an organ preservation strategy could be offered as a reasonable option.

GEC ESTRO ACROP consensus recommendations for contact brachytherapy for rectal cancer

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CXB appears to be an efficacious technique for rectal cancer treatment and may allow rectal preservation in selected patients.

•

These GEC ESTRO ACROP recommendations recommend dose schemes in for rectal CXB.

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These recommendations advise reporting of tumour depth to enable future refinement of dose prescription and target definition.

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The routine collection and publication of outcome data including patient reported outcomes (PROs) is recommended.

Purpose

To issue consensus recommendations for contact X-Ray brachytherapy (CXB) for rectal cancer covering pre-treatment evaluation, treatment, dosimetric issues and follow-up. These recommendations cover CXB in the definitive and palliative setting.

Methods

Members of GEC ESTRO with expertise in rectal CXB issued consensus-based recommendations for CXB based on literature review and clinical experience. Levels of evidence according to the Oxford Centre for Evidence based medicine guidance are presented where possible.

Results

The GEC ESTRO ACROP consensus recommendations support the use of CXB to increase the chances of clinical complete remission and cure for patients who are elderly with high surgical risk, surgically unfit or refusing surgery. For palliative treatment, the use of CXB is recommended for symptomatic relief and disease control. The use of CXB in an organ-preservation setting in surgically fit patients is recommended within the setting of a clinical trial or registry.

Conclusions

The GEC ESTRO ACROP recommendations for CXB are provided. Recommendations towards standardisation of reporting and prescription are given. Practitioners are encouraged to follow these recommendations and to develop further clinical trials to examine this treatment modality and increase the evidence base for its use. The routine collection of outcomes both clinical and patient-reported is also encouraged.

The "Immunoscore" in rectal cancer: could we search quality beyond quantity of life?

Because of the function and anatomical environment of the rectum, therapeutic strategies for local advanced rectal cancer (LARC) must deal with two challenging stressors that are a high-risk of local and distal recurrences and a high-risk of poor quality of life (QoL). Over the last three decades, advances in screening tests, therapies, and combined-modality treatment options and strategies have improved the prognosis of patients with LARC. However, owing to the heterogeneous nature of LARC and genetic status, the patient may not respond to a specific therapy and may be at increased risk of side-effects without the life-prolonging benefit. Indeed, each therapy can cause its own side-effects, which may worsen by a combination of treatments resulting in long-term poor QoL. In LARC, QoL has become even more essential with the increasing incidence of rectal cancer in young individuals. Herein, we analyzed the value of the Immunoscore-Biopsy (performed on tumor biopsy at diagnosis) in predicting outcomes, alone or in association with clinical and imaging data, for each therapy used in LARC.

Evaluation and Predictive Factors of Complete Response in Rectal Cancer after Neoadjuvant Chemoradiation Therapy

The response to neoadjuvant chemoradiation therapy is an important prognostic factor for locally advanced rectal cancer. Although the majority of the patients after neoadjuvant therapy are referred to following surgery, the clinical data show that complete clinical or pathological response is found in a significant proportion of the patients. Diagnostic accuracy of confirming the complete response has a crucial role in further management of a rectal cancer patient. As the rate of clinical complete response, unfortunately, is not always consistent with pathological complete response, accurate diagnostic parameters and predictive markers of tumor response may help to guide more personalized treatment strategies and identify potential candidates for nonoperative management more safely. The management of complete response demands interdisciplinary collaboration including oncologists, radiotherapists, radiologists, pathologists, endoscopists and surgeons, because the absence of a multidisciplinary approach may compromise the oncological outcome. Prediction and improvement of rectal cancer response to neoadjuvant therapy is still an active and challenging field of further research. This literature review is summarizing the main, currently known clinical information about the complete response that could be useful in case if encountering such condition in rectal cancer patients after neoadjuvant chemoradiation therapy, using as a source PubMed publications from 2010–2021 matching the search terms “rectal cancer”, “neoadjuvant therapy” and “response”.

Outcomes of robotic partial excision of the levator ani muscle for locally advanced low rectal cancer invading the ipsilateral pelvic floor at the anorectal ring level

PURPOSE

The purpose of this study is to evaluate partial excision of the levator ani muscle (PELM) enables preservation of anal sphincter function although levator ani muscle (LAM) was invaded.

METHODS

Functional outcomes and oncologic outcomes of 23 consecutive patients who underwent robotic PELM for low rectal cancer at the anorectal ring level invading or abutting the ipsilateral LAM are analysed.

RESULTS

Secured resection margins were achieved, especially for the circumferential resection margin. During a median follow-up of 44 months, the 3-year local recurrence rate was 14.4%. Among patients who underwent diverting ileostomy closure, mean Memorial Sloan Kettering Cancer Center Bowel Function Instrument and Wexner scores were 68.3 ± 11.9 and 10.7 ± 5.3, respectively, at 1 year after closure.

CONCLUSION

PELM is a sphincter-preserving alternative to abdominoperineal resection (APR) or extralevator APR for low rectal cancer invading the ipsilateral LAM at the level of the anorectal ring.

Contact X-ray brachytherapy for rectal cancer: Past, present, and future

The Papillon experience and the Lyon R96-02 trial have shown that contact X-ray brachytherapy of 50kV is efficient and safe to achieve long term local control and organ preservation for cT1 and early cT2-3 rectal cancers. The OPERA trial, using the Papillon 50™ machine, brings further support to this preservation strategy for selected T2T3ab lesions. Future trials using a contact X-ray boost will try to consolidate and enlarge its place in organ preservation for rectal cancers.

Intersphincteric resection for low rectal cancer: the risk is functional rather than oncological. A 25-year experience from Bordeaux

AIM

There are few data evaluating the long-term outcomes of intersphincteric resection (ISR), especially the impact of inclusion of more juxtapositioned and intra-anal tumours on oncological and functional outcomes. We compared the oncological and functional results of patients treated by total mesorectal excision and ISR for low rectal cancer over a 25-year period.

METHOD

This is a retrospective study from a single institution evaluating results of ISR over three periods: 1990-1998, 1999-2006 and 2007-2014. Patients treated by partial or total ISR, with or without neoadjuvant chemoradiotherapy, for low rectal cancer (≤ 6 cm from the anal verge) were included. We compared postoperative morbidity, quality of surgery and oncological and functional outcomes in the time periods studied.

RESULTS

Of 813 patients operated on for low rectal cancer, 303 had ISR. Tumour stage did not differ; however, the distance of the tumour from the anorectal junction decreased from 1 to 0 cm (P < 0.001) and the distal resection margin shortened from 25 to 10 mm (P < 0.001) from 1990 to 2014. The postoperative morbidity and quality of surgery did not change significantly over time. The 5-year local recurrence (4.3% vs 5.9% vs 3.5%; P = 0.741) and disease-free survival (72% vs 71% vs 75%; P = 0.918) did not differ between the three time periods. Functional results improved during the last period; however, overall 42% of patients experienced major bowel dysfunction.

CONCLUSION

Pushing the envelope of sphincter-saving resection in ultra-low rectal cancer reaching or invading the anal sphincter did not compromise oncological and functional outcomes. The main limitation of the ISR procedure appears to be functional rather than oncological, suggesting that bowel rehabilitation programmes should be developed.

A Snapshot of the International Views of the Treatment of Rectal Cancer Patients, a Multi-regional Survey: International Tendencies in Rectal Cancer

BACKGROUND

Management of rectal cancer has a number of potentially appropriate alternatives for each patient. Despite acceptance of standards, practices may vary among regions. There is significant paucity of data in this area. The objective was to create a snapshot of the regional differences.

DESIGN

This online survey included 10 questions. Enquiries focused on controversial topics, on surgeon and hospital volume, surgical margins, appropriateness of surgical approaches and techniques, watch-and-wait strategies, and total neoadjuvant therapy. Major colorectal surgery societies around the world were asked to invite their members to complete the survey.

OUTCOME MEASURES

Frequency of responses across regions within each question was compared by Fisher's exact test.

RESULTS

Seven hundred and fifty-three participants from 60 countries responded. Eight regions were identified, and four had sufficient representation for comparisons. Similarities and differences in the therapies among these regions were identified. Robotic surgery penetrance is higher in North America, and watch and wait is more accepted in South America. Patients in Oceania are more likely to be diverted; Europe has more usage of taTME.

DISCUSSION

This online survey was practical as a mean to provide a rapid assessment of the international picture on consistency and variability of rectal cancer patients' care, and to potentially identify opportunities to standardized care to patients. Medical surveys have inherent limitations; pertinence to our study is selection bias.

CONCLUSIONS

The management of rectal cancer varies among different regions. Identification of differences is important when considering global efforts to improve management and interpret data.

Retrospective study of preoperative chemoradiotherapy with capecitabine versus capecitabine plus oxaliplatin for locally advanced rectal cancer

This study aimed to evaluate whether the addition of oxaliplatin to a neoadjuvant chemoradiotherapy (CRT) regimen could improve survival benefit in locally advanced rectal cancer (LARC) patients. We retrospectively analysed 73 LARC patients (cT2-4 and/or cN1-2) who received preoperative CRT with capecitabine followed by surgery (arm A, 43 patients) or capecitabine plus oxaliplatin followed by surgery (arm B, 30 patients). The main endpoints of the study were pathologic complete response (pCR) rate, overall survival (OS) and disease-free survival (DFS). The secondary endpoints included the sphincter preservation rate and safety. The pCR for arms A and B were 28% and 17% (P = 0.267). In arms A and B, the mean OS was 84.287 months (95% CI 68.413-100.160) and 106.333 months (95% CI 99.281-113.386) (P = 0.185); the mean DFS was 72.812 months (95% CI 56.271-89.353) and 95.073 months (95% CI 83.392-106.754) (P = 0.310); and the sphincter preservation rates were 72% and 67%, respectively (P = 0.619). The incidence of grade 3 toxicity was much higher in arm B than in arm A (57% vs. 21%, P = 0.002). Adding oxaliplatin to a preoperative CRT regimen for LARC did not improve the survival benefits of patients or increase toxicity.

Toxicity outcome of endorectal brachytherapy boost in medically inoperable patients

AIM

This communication reviews results and toxicity of image-guided high-dose-rate endorectal brachytherapy (HDREBT) boost after external beam radiotherapy (ERT) in medically inoperable patients with rectal cancer.

MATERIALS AND METHODS

A total of 18 patients with rectal cancer and clinical stage T2-4N0‑2 treated with HDREBT boost after ERT were retrospectively reviewed.

RESULTS

Following treatment with a median total dose (EQD2, α/β = 10) of 66 Gy (range 48-92 Gy), the incidence of early and late rectal grade 3 toxicity was 11% and 19%, respectively. There was no correlation between the occurrence of acute and late toxicity.

CONCLUSION

With proper technique, a combined approach using EBRT and HDREBT was associated with acceptable toxicity in medically inoperable rectal cancer patients.

A brief history of contact X-ray brachytherapy 50 kVp

Contact X ray brachytherapy 50 kVp was initiated in the 1930s with the Siemens unit and popularized with the Philips unit in the 1950s. A renaissance was seen in the early 2000s with the Intrabeam™ unit for breast IORT. Presently the Papillon™ systems thanks to its high dose rate (>10Gy/mn) can be used to treat breast (IORT), skin, eyelid and rectal cancers. Future developments are expected to consolidate the place of contact radiotherapy as a safe and efficient treatment for accessible early tumors.

Role of radiotherapy in the treatment of rectal cancer in older patients

Striking a balance between cancer treatment and patient-centred care is becoming ever more important in older patients with rectal cancer as the population is ageing. The treatment decision made by the modern multidisciplinary colorectal team will recommend pre-operative chemo-radiotherapy followed by surgery for advance rectal cancer and surgery alone for early rectal cancer, as the "standard of care" is surgery. However, an alternative non-surgical treatment option should be consider for older patients with rectal cancer as the surgical harm can far outweigh the potential benefits. There is published evidence that mortality is higher with increasing age. An alternative treatment option to surgery when patients are not suitable or refusing surgery is to offer them external beam radiotherapy (EBRT) or chemo radiotherapy (EBCRT). A proportion of these patients can achieve a clinical complete response (cCR) which enable adoption of 'watch and wait' strategy to avoid surgery. However, a third of patients who achieved initial cCR can develop local regrowth within the first two years. This require salvage surgery which reduces their chance of organ preservation. Contact X-ray brachytherapy (CXB) or High Dose Rate Endo Brachy Therapy (HDREBT) boost following external beam radiotherapy can improve the initial cCR rate and reduce the risk of local regrowth. Those patients with persistent residual cancer or regrowth after brachytherapy boost following EBCRT or EBRT can have salvage surgery later without compromising their chance of cure. Therefore, patients should be fully aware of their treatment options and have 'a choice' when deciding and consenting their treatment.

Microscopic intramural extension of rectal cancer after neoadjuvant chemoradiation: A meta-analysis based on individual patient data

OBJECTIVE

In selected rectal cancer patients with residual local disease following neoadjuvant chemoradiation (CRT) and the preference of an organ preservation pathway, additional treatment with dose escalation by endoluminal radiotherapy (RT) may ultimately result in a clinical complete response. To date, the widespread introduction of selective endoluminal radiation techniques is hampered by a lack of evidence-based guidelines that describe the radiation treatment volume in relation to the residual tumor mass. In order to convert an incomplete response into a complete one with additional treatment such as dose-escalation with endoluminal RT from a theoretical perspective, it seems important to treat all remaining microscopic tumor cells after CRT. In this setting, residual tumor extension beneath normal appearing mucosa (microscopic intramural spread - MIS) becomes relevant for accurate tumor volume and margin estimation. With the goal of providing evidence-based guidelines that define an appropriate treatment volume and patient selection, we present results from a meta-analysis based on individual patient data of studies that have assessed the extent or range of MIS of rectal cancers after neoadjuvant CRT. This meta-analysis should provide an estimate of the residual tumor volume/extension that needs to be targeted by any additional radiation therapy boost in order to achieve complete tumor eradication after initial incomplete or near-complete response following standard CRT.

METHODS AND MATERIALS

A PubMed search was performed. Additional articles were selected based on identification from reference lists. Papers were eligible when reporting MIS in patients who were treated by total mesorectal excision or local excision/transanal endoscopic microsurgery (TEM) after neo-adjuvant long-course CRT. The mean MIS was calculated for the entire group along with the 70th until 95th percentiles. Additional exploratory subgroup analyses were performed.

RESULTS

Individual patient data from 349 patients with residual disease from five studies were analyzed. 80% of tumors showed no MIS. In order to appropriately treat MIS in 95% of rectal cancer patients after CRT, a margin of 5.5 mm around the macroscopic tumor would suffice. An exploratory subgroup analysis showed that T-stage after CRT (ypT) and time interval between neoadjuvant CRT and surgery are significant factors predicting the extent of MIS (p < 0.001.) The group of ypT1 had the smallest MIS, followed by the ypT3-4 group, while the ypT2 group had the largest MIS (p < 0.001). Regarding time interval between CRT and surgery, a statistically significant difference was seen when comparing the three time-interval groups (less than 8 weeks, 8-12 weeks, and more than 12 weeks), where waiting more than 12 weeks after CRT resulted in the largest MIS (p < 0.0001).

CONCLUSION

Based on this meta-analysis, in order to treat the MIS for 95% of rectal cancer patients after CRT, a Clinical Target Volume (CTV) margin of 5.5 mm from the lateral most edge of the macroscopic tumor would suffice. 80% of tumors showed no MIS and would not require an extra CTV margin for treatment. These findings support the feasibility of localized radiotherapy boosts for dose-escalation to improve response among patients with incomplete response after standard CRT and can also be applied in the surgical setting.

Rectal cancer MR staging: pearls and pitfalls at baseline examination

In recent years, rectal MRI has become a central diagnostic tool in rectal cancer staging. Indeed, rectal MR has the ability to accurately evaluate a number of important findings that may impact patient management, including distance of the tumor to the mesorectal fascia, presence of extramural vascular invasion (EMVI), presence of lymph nodes, and involvement of the peritoneum/anterior peritoneal reflection. Many of these findings are difficult to assess in nonexpert hands. In this review, we present a practical approach for radiologists to provide high-quality interpretations at initial baseline exams, based on recent guidelines from the Society of Abdominal Radiology, Rectal and Anal Cancer Disease Focused Panel. Practical pearls and pitfalls are discussed, focusing on optimization of technique including, patient preparation and protocol recommendations, interpretation, and essentials of reporting.

"Watch and Wait" for complete clinical response after neoadjuvant chemoradiotherapy for rectal cancer

The management of rectal cancer has evolved substantially over recent decades, becoming increasingly complex. This was once a disease associated with high mortality and limited treatment options that typically necessitated a permanent colostomy, has now become a model for multidisciplinary evaluation, treatment and surgical advancement. Despite advances in the rates of total mesorectal excision, decreased local recurrence and increased 5-year survival rates, the multimodal treatment of rectal cancer is associated with a significant impact on long-term functional and quality of life outcomes including risks of bowel, bladder and sexual dysfunction, and potential need for a permanent stoma. There is great interest in strategies to decrease the toxicity of treatment, including selective use of radiation, chemotherapy or even surgery. The modern concept of selective use of surgery for patients with rectal cancer are based on the observed pathological complete response in approximately 10-20% of patients following long-course chemoradiation therapy. While definitive surgical resection remains the standard of care for all patients with non-metastatic rectal cancer, a growing number of studies are providing supportive evidence for a watch-and-wait, organ preserving approach in highly selected patients with rectal cancer. However, questions regarding the heterogeneity of patient selection, optimal method for inducing pathological complete response, methods and intervals for assessing treatment response and adequacy of follow-up remain unanswered. The aim of this review is to provide an up-to-date summary of the current evidence for the watch-and-wait management of rectal cancer following a complete clinical response after neoadjuvant chemoradiation.

Neoadjuvant radiotherapy for rectal cancer management

Thirty per cent of all colorectal tumours develop in the rectum. The location of the rectum within the bony pelvis and its proximity to vital structures presents significant therapeutic challenges when considering neoadjuvant options and surgical interventions. Most patients with early rectal cancer can be adequately managed by surgery alone. However, a significant proportion of patients with rectal cancer present with locally advanced disease and will potentially benefit from down staging prior to surgery. Neoadjuvant therapy involves a variety of options including radiotherapy, chemotherapy used alone or in combination. Neoadjuvant radiotherapy in rectal cancer has been shown to be effective in reducing tumour burden in advance of curative surgery. The gold standard surgical rectal cancer management aims to achieve surgical removal of the tumour and all draining lymph nodes, within an intact mesorectal package, in order to minimise local recurrence. It is critically important that all rectal cancer cases are discussed at a multidisciplinary meeting represented by all relevant specialties. Pre-operative staging including CT thorax, abdomen, pelvis to assess for distal disease and magnetic resonance imaging to assess local involvement is essential. Staging radiology and MDT discussion are integral in identifying patients who require neoadjuvant radiotherapy. While Neoadjuvant radiotherapy is potentially beneficial it may also result in morbidity and thus should be reserved for those patients who are at a high risk of local failure, which includes patients with nodal involvement, extramural venous invasion and threatened circumferential margin. The aim of this review is to discuss the role of neoadjuvant radiotherapy in the management of rectal cancer.

Preoperative Volumetric Modulated Arc Therapy With Simultaneous Integrated Boost for Locally Advanced Distal Rectal Cancer

The aim of this study was to evaluate the safety and clinical efficacy of a combined preoperative regimen consisting of volumetric modulated arc therapy–simultaneous integrated boost and capecitabine chemotherapy for distal rectal cancer. A total of 26 patients with locally advanced distal rectal cancer were enrolled from March 2015 to May 2016. The radiation dose fractionation was 58.75 Gy/25 fractions (2.35 Gy/fraction) for rectal tumor and pelvic lymph node metastasis and 50 Gy/25 fractions for pelvic lymph node stations, accompanied with simultaneous capecitabine chemotherapy. Completion of the simultaneous chemotherapy was ensued by 1 week of rest and then another cycle of induction chemotherapy with capecitabine. A radical rectal cancer surgery was performed 6 to 8 weeks after the simultaneous chemoradiotherapy. The primary end points were the complete pathological response rate and the postoperative sphincter preservation rate. All 26 patients completed the neoadjuvant chemoradiotherapy, among which 25 received surgical treatment. The postoperative complete pathological response rate was as high as 32% (8/25), while the sphincter preservation rate was 60% (15/25), the overall tumor/node (T/N) downstaging rate was 92% (23/25), and the R0 resection rate was 100%. During the chemoradiation, the most common adverse events were grade 1 and 2; grade 3 radiodermatitis occurred in 2 cases but no occurrence of acute adverse events occurred that were grade 4 and above. After the surgery, there was one case of ureteral injury and one case of intestinal obstruction, but no perioperative deaths occurred. In conclusion, the chemoradiation regimen of preoperative volumetric modulated arc therapy-simultaneous integrated boost (VMAT-SIB_58.75Gy) and a single cycle of induction chemotherapy with capecitabine for patients with distal rectal cancer is safe and feasible with a satisfactory complete pathological response rate, sphincter preservation rate, and R0 resection rate.

Determining the use of preoperative (chemo)radiotherapy in primary rectal cancer according to national and international guidelines

BACKGROUND

Pre-operative radiotherapy (RT) or chemoradiotherapy (CRT) is frequently used prior to rectal cancer surgery to improve local control and survival. The treatment is administered according to guidelines, but these recommendations vary significantly between countries. Based on the stage distribution and risk factors of rectal cancers as determined by magnetic resonance imaging (MRI) in an unselected Swedish population, the use of RT/CRT according to 15 selected guidelines is described.

MATERIALS AND METHODS

Selected guidelines from different countries and regions were applied to a well-characterized unselected population-based material of 686 primary non-metastatic rectal cancers staged by MRI. The fraction of patients assigned to surgery alone or surgery following pre-treatment with (C)RT was determined according to the respective guideline. RT/CRT administered to rectal cancer patients for other reasons, for example, for organ preservation or palliation, was not considered.

RESULTS

The fraction of patients with a clear recommendation for pre-treatment with (C)RT varied between 38% and 77% according to the different guidelines. In most guidelines, CRT was recommended to all patients who were not operated directly, and, in others, short-course RT was also recommended to patients with intermediate risk tumours. If only non-resectable or difficult to resect tumours were recommended pre-treatment, as stated in many Japanese publications, 9% would receive CRT followed by a delay to surgery.

CONCLUSIONS

According to most guidelines, well over 50% of primary non-metastatic rectal cancer patients from a general population, in which screening for colorectal cancer is not practised, are recommended treatment with pre-operative/neo-adjuvant therapy.

How to Achieve a Higher Pathologic Complete Response in Patients With Locally Advanced Rectal Cancer Who Receive Preoperative Chemoradiation Therapy

The current standard of care for treating patients with locally advanced rectal cancer includes preoperative chemoradiation therapy (PCRT) followed by a total mesorectal excision and postoperative adjuvant chemotherapy. A subset of these patients has achieved a pathologic complete response (pCR) and they have shown improved disease-free and overall survival compared to non-pCR patients. Thus, many efforts have been made to achieve a higher pCR through PCRT. In this review, results from various ongoing and recently completed clinical trials that are being or have been conducted with an aim to improve tumor response by modifying therapy will be discussed.

Obesity as an independent predictive factor for pathologic complete response after neoadjuvant chemoradiation in rectal cancer

PURPOSE

The predictive role of obesity on pathologic complete response (pCR) after neoadjuvant chemoradiation (nCRT) in rectal cancer remains controversial. This study aimed to evaluate the association between obesity and pathologic response in patients with rectal cancer following nCRT.

METHODS

A total of 320 patients with primary rectal cancer who underwent curative resection after nCRT between January 2010 and September 2014 were enrolled in this study. Obesity was defined as body mass index of ≥25 kg/m2. Clinicopathologic characteristics were analyzed to identify independent predictive factors for pCR.

RESULTS

Among the included patients, 23.4% (n = 75) were obese, and 14.7% (n = 47) showed pCR. Baseline characteristics were generally similar between obese and nonobese patients, except that women (P = 0.001) and cT2 tumors (P = 0.001) were more common in the obese group. Multivariate logistic regression analysis revealed that obesity (odds ratio [OR] = 2.051; 95% confidence interval [CI], 1.009-4.168), cT2 (OR, 3.614; 95% CI, 1.166-11.202), and pretreatment carcinoembryonic antigen <5 ng/mL (OR, 2.921; 95% CI, 1.365-6.253) were independent predictors for pCR. Obesity was not associated with disease-free survival or local recurrence-free survival.

CONCLUSION

Obesity was an independent predictive factor for pCR following nCRT in rectal cancer, but was not associated with recurrence. Further studies are needed to clarify the association between obesity and prognosis of rectal cancer after nCRT.

Planned organ preservation for early T2-3 rectal adenocarcinoma: A French, multicentre study

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) and watch-and-wait policy as reported by Habr-Gama are references for organ preservation in rectal cancer. To increase the clinical complete response (cCR) and reduce the local recurrence rates, we report a retrospective analysis of a prospective cohort of selected T2-3 tumours treated in three French institutions using contact X-ray brachytherapy (CXB) with nCRT.

METHODS

Tumour selection was based on digital rectal examination (DRE), rigid rectoscopy, magnetic resonance imaging (MRI) and/or endorectal ultrasound. Adenocarcinoma T2-3 < 5 cm largest diameter, M0 were treated, all with organ preservation intent. CXB delivering 90 Gy/3 fractions/4 weeks was combined with CRT (capecitabine 50). Strict evaluation of tumour response using DRE and rectoscopy ± MRI was performed at regular interval with prolonged surveillance.

FINDINGS

Between 2002 and 2016, 74 consecutive patients were treated (median age: 74 years. T2: 45 and T3: 29). A cCR or near-cCR (mainly rectal wall ulceration) was noted at week 14 in 71 patients (95%). A local excision was performed in 13 patients. Of three partial responses (PRs), one salvage anterior resection was performed. With a median follow-up of 3 years, local recurrence (mainly in the rectal wall) was seen in seven patients. The 3-year local recurrence rate was 10%, and the cancer-specific survival, 88%. Two patients underwent radical proctectomy for PR or local recurrence and 96% preserved their rectum. Grade III acute toxicity was recorded in five patients. Rectal bleeding was the main late toxicity (grade III in 12%). Bowel function was scored as good or excellent in 85% of patients.

INTERPRETATION

Combining CXB and nCRT in selected early T2-T3 rectal cancers may safely provide a high rate of cCR, organ preservation, and good bowel function with a risk of local recurrence below 15%. Such an approach could be offered to operable patients as a planned option for organ preservation.

Impact of VMAT-IMRT compared to 3D conformal radiotherapy on anal sphincter dose distribution in neoadjuvant chemoradiation of rectal cancer

Background

Neoadjuvant radio- or chemoradiation (nIRT) therapy is the standard treatment for loco-regional advanced rectal cancer patients of the lower or middle third. Currently, intensity modulated radiation therapy (IMRT) is not the recommended radiation technique even though IMRT has advantages compared to 3D-radiation regarding dose sparing to organs at risk like small bowel and urinary bladder. So far, the benefit of IMRT concerning the anal sphincter complex is not examined. With this study we intended to evaluate the dose distribution on the anal sphincters of rectal cancer patients treated with IMRT in comparison with 3D-techniques.

Methods

We selected 16 patients for the IMRT-group and 16 patients for the 3D-group with rectal cancer of the middle third who were treated in our institute. All patients received 45 Gy in a chemoradiation protocol. Patients in both groups were matched regarding stage, primary tumor distance to the anal verge and size of the tumor. We delineated the internal and external anal sphincters, the addition of both sphincters and the levator ani muscle in all patients. Subsequently, we evaluated and compared dose parameters of the different sphincters in both groups and analysed the configuration of the isodoses in the area of the caudal radiation field, respectively.

Results

Most of the relevant dose parameters of the caudal sphincters (Dmean, Dmedian, V10–V40) were significantly reduced in the IMRT-group compared to the 3D-group. Accordingly, the isodoses at the caudal edge of the target volume in the IMRT group demonstrated a steep dose fall. The levator ani muscle always was included into the planned target volumes and received the full dose in both groups.

Conclusions

The modern VMAT-IMRT can significantly reduce the dose to the anal sphincters for rectal cancer patients of the middle third who were treated with conventional chemoradiation therapy.

Systematic review of treatment intensification using novel agents for chemoradiotherapy in rectal cancer

BACKGROUND

With the well established shift to neoadjuvant treatment for locally advanced rectal cancer, there is increasing focus on the use of radiosensitizers to improve the efficacy and tolerability of radiotherapy. There currently exist few randomized data exploring novel radiosensitizers to improve response and it is unclear what the clinical endpoints of such trials should be.

METHODS

A qualitative systematic review was performed according to the PRISMA guidelines using preset search criteria across the PubMed, Cochrane and Scopus databases from 1990 to 2017. Additional results were generated from the reference lists of included papers.

RESULTS

A total of 123 papers were identified, of which 37 were included; a further 60 articles were obtained from additional referencing to give a total of 97 articles. Neoadjuvant radiosensitization for locally advanced rectal cancer using fluoropyrimidine-based chemotherapy remains the standard of treatment. The oral derivative capecitabine has practical advantages over 5-fluorouracil, with equal efficacy, but the addition of a second chemotherapeutic agent has yet to show a consistent significant efficacy benefit in randomized clinical assessment. Preclinical and early-phase trials are progressing with promising novel agents, such as small molecular inhibitors and nanoparticles.

CONCLUSION

Despite extensive research and promising preclinical studies, a definite further agent in addition to fluoropyrimidines that consistently improves response rate has yet to be found.

Preoperative radiotherapy and curative surgery for the management of localised rectal carcinoma

BACKGROUND

This is an update of the original review published in 2007.Carcinoma of the rectum is a common malignancy, especially in high income countries. Local recurrence may occur after surgery alone. Preoperative radiotherapy (PRT) has the potential to reduce the risk of local recurrence and improve outcomes in rectal cancer.

OBJECTIVES

To determine the effect of preoperative radiotherapy for people with localised resectable rectal cancer compared to surgery alone.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library; Issue 5, 2018) (4 June 2018), MEDLINE (Ovid) (1950 to 4 June 2018), and Embase (Ovid) (1974 to 4 June 2018). We also searched ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) for relevant ongoing trials (4 June 2018).

SELECTION CRITERIA

We included randomised controlled trials comparing PRT and surgery with surgery alone for people with localised advanced rectal cancer planned for radical surgery. We excluded trials that did not use contemporary radiotherapy techniques (with more than two fields to the pelvis).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the 'Risk of bias' domains for each included trial, and extracted data. For time-to-event data, we calculated the Peto odds ratio (Peto OR) and variances, and for dichotomous data we calculated risk ratios (RR) using the random-effects method. Potential sources of heterogeneity hypothesised a priori included study quality, staging, and the use of total mesorectal excision (TME) surgery.

MAIN RESULTS

We included four trials with a total of 4663 participants. All four trials reported short PRT courses, with three trials using 25 Gy in five fractions, and one trial using 20 Gy in four fractions. Only one study specifically required TME surgery for inclusion, whereas in another study 90% of participants received TME surgery.Preoperative radiotherapy probably reduces overall mortality at 4 to 12 years' follow-up (4 trials, 4663 participants; Peto OR 0.90, 95% CI 0.83 to 0.98; moderate-quality evidence). For every 1000 people who undergo surgery alone, 454 would die compared with 45 fewer (the true effect may lie between 77 fewer to 9 fewer) in the PRT group. There was some evidence from subgroup analyses that in trials using TME no or little effect of PRT on survival (P = 0.03 for the difference between subgroups).Preoperative radiotherapy may have little or no effect in reducing cause-specific mortality for rectal cancer (2 trials, 2145 participants; Peto OR 0.89, 95% CI 0.77 to 1.03; low-quality evidence).We found moderate-quality evidence that PRT reduces local recurrence (4 trials, 4663 participants; Peto OR 0.48, 95% CI 0.40 to 0.57). In absolute terms, 161 out of 1000 patients receiving surgery alone would experience local recurrence compared with 83 fewer with PRT. The results were consistent in TME and non-TME studies.There may be little or no difference in curative resection (4 trials, 4673 participants; RR 1.00, 95% CI 0.97 to 1.02; low-quality evidence) or in the need for sphincter-sparing surgery (3 trials, 4379 participants; RR 0.99, 95% CI 0.94 to 1.04; I² = 0%; low-quality evidence) between PRT and surgery alone.Low-quality evidence suggests that PRT may increase the risk of sepsis from 13% to 16% (2 trials, 2698 participants; RR 1.25, 95% CI 1.04 to 1.52) and surgical complications from 25% to 30% (2 trials, 2698 participants; RR 1.20, 95% CI 1.01 to 1.42) compared to surgery alone.Two trials evaluated quality of life using different scales. Both studies concluded that sexual dysfunction occurred more in the PRT group. Mixed results were found for faecal incontinence, and irradiated participants tended to resume work later than non-irradiated participants between 6 and 12 months, but this effect had attenuated after 18 months (low-quality evidence).

AUTHORS' CONCLUSIONS

We found moderate-quality evidence that PRT reduces overall mortality. Subgroup analysis did not confirm this effect in people undergoing TME surgery. We found consistent evidence that PRT reduces local recurrence. Risk of sepsis and postsurgical complications may be higher with PRT.The main limitation of the findings of the present review concerns their applicability. The included trials only assessed short-course radiotherapy and did not use chemotherapy, which is widely used in the contemporary management of rectal cancer disease. The differences between the trials regarding the criteria used to define rectal cancer, staging, radiotherapy delivered, the time between radiotherapy and surgery, and the use of adjuvant or postoperative therapy did not appear to influence the size of effect across the studies.Future trials should focus on identifying participants that are most likely to benefit from PRT especially in terms of improving local control, sphincter preservation, and overall survival while reducing acute and late toxicities (especially rectal and sexual function), as well as determining the effect of radiotherapy when chemotherapy is used and the optimal timing of surgery following radiotherapy.

Contact X-ray Brachytherapy as an Adjunct to a Watch and Wait Approach is an Affordable Alternative to Standard Surgical Management of Rectal Cancer for Patients with a Partial Clinical Response to Chemoradiotherapy

AIMS

Emerging evidence suggests that contact X-ray brachytherapy (CXB) may increase the clinical complete response rate and durability when administered after standard chemoradiotherapy in patients with rectal cancer. The addition of CXB in partial responders is therefore probably cost-effective. The affordability of widening access to CXB in the UK, however, has not been evaluated.

MATERIALS AND METHODS

Decision analytical modelling with Monte Carlo simulation was used to evaluate long-term costs for the management of patients with rectal cancers who were given a CXB boost when a clinical complete response was not initially achieved following chemoradiotherapy in order to facilitate a watch and wait approach. A third-party payer (National Health Service) perspective was adopted, probabilistic sensitivity analysis was carried out and a scenario analysis was performed to investigate the effect of the number of referral centres and number of patients treated with CXB.

RESULTS

We estimate that 818 (95% confidence interval 628-1021) patients per year are eligible for CXB as an adjunct to a watch and wait approach in England and Wales. As this management is less costly than surgical management for each individual patient, the more patients treated, the more affordable the technology. Even if as few as 125 patients are treated nationally in 15 centres, the cost of implementing this technology would be less than £4 million. If the average number of patients treated in each centre is 30, this technology would be cost saving within 5 years.

CONCLUSIONS

The cost of CXB is not prohibitive according to the National Institute for Health and Care Excellence threshold for implementation of new technology and may even be cost saving within 5 years compared with standard surgical management, depending on the uptake of the technology and the number of referral centres.

A novel rectal applicator for contact radiotherapy with HDR 192Ir sources

PURPOSE

Dose escalation to rectal tumors leads to higher complete response rates and may thereby enable omission of surgery. Important advantages of endoluminal boosting techniques include the possibility to apply a more selective/localized boost than using external beam radiotherapy. A novel brachytherapy (BT) rectal applicator with lateral shielding was designed to be used with a rectoscope for eye-guided positioning to deliver a dose distribution similar to the one of contact x-ray radiotherapy devices, using commonly available high-dose-rate ¹⁹²Ir BT sources.

METHODS AND MATERIALS

A cylindrical multichannel BT applicator with lateral shielding was designed by Monte Carlo modeling, validated experimentally with film dosimetry and compared with results found in the literature for the Papillon 50 (P50) contact x-ray radiotherapy device regarding rectoscope dimensions, radiation beam shape, dose fall-off, and treatment time.

RESULTS

The multichannel applicator designed is able to deliver 30 Gy under 13 min with a 20350 U (5 Ci) source. The use of multiple channels and lateral shielding provide a uniform circular treatment surface with 22 mm in diameter. The resulting dose fall-off is slightly steeper (maximum difference of 5%) than the one generated by the P50 device with the 22 mm applicator.

CONCLUSIONS

A novel multichannel rectal applicator for contact radiotherapy with high-dose-rate ¹⁹²Ir sources that can be integrated with commercially available treatment planning systems was designed to produce a dose distribution similar to the one obtained by the P50 device.

Session 4: Trying to augment response with chemotherapy: a triumph of hope over experience?

As part of an approach to improve tumour regression and increase the proportion of patients with complete clinical and radiological response, Dr Perez reviews the methods and evidence base for augmenting therapy and thus augmenting response rates preoperatively. Much of the data reviewed were in the context of patients undergoing a watch-and-wait approach for rectal cancer after initial treatment with chemoradiotherapy.

Session 4: Shaping radiotherapy for rectal cancer: should this be personalized?

Preoperative radiotherapy continues to be widely used in patients with operable rectal cancer. However, the indications and goals for such treatment are evolving. Professor Marijnen reviews the historic and current evidence base for the use of preoperative neoadjuvant radiotherapy and the future challenges in tailoring the therapy according to the patients' needs and tumour stage.