Could a wait and see policy be justified in T3/4 rectal cancers after chemo-radiotherapy?

Usefulness of close surveillance for rectal cancer patients after neoadjuvant chemoradiotherapy

It is controversial whether patients who achieve clinical complete remission (cCR) of rectal cancer should be treated with the “watch and wait” (W&W) or radical resection (RR) strategy. Our study aimed to compare the survival outcomes and ostomy rate of the W&W and RR strategies. Between January 2008 and December 2015, we investigated 26 patients who achieved pathologic complete remission after undergoing RR and 36 patients who adopted the W&W strategy because of cCR. The tumor regrowth, salvage surgery, recurrence, disease-free, and overall survival (OS) rates were assessed. In our study, recurrences occurred in nine and two patients from the W&W and RR groups, respectively. Each patient in the RR group had a temporary or permanent ostomy, but only three (8.3%) had an ostomy in the W&W group. The 5-year recurrence rate was 25.0% in the W&W group and 7.7% in the RR group. Six patients (16.7%) had tumor regrowth in the W&W group, and all were resectable when regrowth. The 5-year OS rates between the two groups were nonsignificant. There is no specific risk factor for recurrence and OS. Under close surveillance, the W&W group achieved similar OS to the RR group and benefited from a lower ostomy rate.

A Pilot, Prospective, Observational Study to Investigate the Value of NGS in Liquid Biopsies to Predict Tumor Response After Neoadjuvant Chemo-Radiotherapy in Patients With Locally Advanced Rectal Cancer: The LiBReCa Study

Introduction

Circulating tumor DNA (ctDNA) correlates with the response to therapy in different types of cancer. However, in patients with locally advanced rectal cancer (LARC), little is known about how ctDNA levels change with neoadjuvant chemoradiation (Na-ChRT) and how they correlate with treatment response. This work aimed to explore the value of serial liquid biopsies in monitoring response after Na-ChRT with the hypothesis that this could become a reliable biomarker to identify patients with a complete response, candidates for non-operative management.

Materials and Methods

Twenty-five consecutive LARC patients undergoing long-term Na-ChRT therapy were included. Applying next-generation sequencing (NGS), we characterized DNA extracted from formalin-fixed paraffin embedded diagnostic biopsy and resection tissue and plasma ctDNA collected at the following time points: the first and last days of radiotherapy (T0, Tend), at 4 (T4), 7 (T7) weeks after radiotherapy, on the day of surgery (Top), and 3–7 days after surgery (Tpost-op). On the day of surgery, a mesenteric vein sample was also collected (TIMV). The relationship between the ctDNA at those time-points and the tumor regression grade (TRG) of the surgical specimen was statistically explored.

Results

We found no association between the disappearance of ctDNA mutations in plasma samples and pathological complete response (TRG1) as ctDNA was undetectable in the majority of patients from Tend on. However, we observed that the poor (TRG 4) response to Na-ChRT was significantly associated with a positive liquid biopsy at the Top.

Conclusions

ctDNA evaluation by NGS technology may identify LARC patients with poor response to Na-ChRT. In contrast, this technique does not seem useful for identifying patients prone to developing a complete response.

[Rectal Cancer: Organ preservation and neoadjuvant treatment escalation]

Standard treatment consisting of chemoradiotherapy followed by radical surgery with total mesorectal excision, results in good oncologic local control but high morbidity and poor functional results. Since chemoradiotherapy results in 15% pathological complete response, even reaching up to 30% in case of association with neoadjuvant chemotherapy, radical surgery has been recently debated for good responders. Therefore, a de-escalation strategy, by omitting radical surgery in good responders, has recently been developed with two different options: a watch and wait strategy, requiring an accurate clinical and radiological definition of complete response and a local excision strategy including patients with sub-complete response. Ongoing trials focus on response optimization by chemotherapy intensification or radiotherapy dose escalation. However, many questions are still to be answered regarding definition of complete response, follow-up strategy, morbidity of salvage surgery in case of recurrence as well as long-term oncological and functionnal results.

Could the conservative approach be considered safe in the treatment of locally advanced rectal cancer in case of a clinical near-complete or complete response? A retrospective analysis

Background

Conservative approach has emerged as an option for the management of rectal cancer (RC) patients with a near or complete clinical response after neoadjuvant chemoradiotherapy (nCRT). The aim of this study is to assess the impact of the conservative approach by comparing patients’ survival outcomes and quality of life with those who had surgical resection.

Methods

A single-institution and retrospective study including RC patients who reached a near complete or complete clinical response after nCRT from January 2010 to September 2019. Conservative approaches included local excision or watch and wait strategy; surgery approaches included anterior resection or abdominal-perineal resection.

Local regrowth (LR), overall survival, disease free survival, metastasis free survival and colostomy free survival were evaluated through Kaplan-Meier curves and compared trough log-rank tests. Quality of life was measured by the following validated questionnaires: EORTC QLC30, EORTC QLQ – CR29 and Fecal Incontinence Quality of Life scale.

Results

Overall 157 patients were analyzed: 105 (66,9%) underwent radical surgery and 52 (33,1%) had a conservative approach. With a median follow-up of 51 months, 2 patients in the surgical group had a local recurrence and 8 in the conservative group had a LR, respectively. Distance metastasis occurred in 7 and 1 patients of surgical and conservative group, respectively. No differences were detected in terms of survival outcomes except for colostomy free survival (p: 0,01). The conservative group showed better intestinal (p < 0.01) and sexual (p: 0,04) function and emotional status (p: 0,02).

Conclusions

Conservative approach seems to be safe in terms of survival outcomes with a significant advantage on quality of life in RC patients who achieved clinical complete response after nCRT.

Surgical oncology in the age of multimodality therapy for cancer of the upper and lower gastrointestinal tract

INTRODUCTION

To date, all efforts to fight gastrointestinal cancer, regardless of its origin and entity, have resulted in complex therapeutic regimens involving a combination of systemic therapy, radiation therapy and surgery. It is generally accepted across all disciplines that not one, but the combination and the proper timing of all modalities result in the best oncologic outcome.

AREAS COVERED

Here, we provide insight into the current and future value of multimodal therapeutic approaches for upper and lower gastrointestinal cancer. Various aspects of treatment as well as open questions regarding indication and timing of multimodal strategies are addressed in this review.

EXPERT OPINION

In order to further improve the survival and quality of life of patients with gastrointestinal tumors in the future, scientifically proven multimodal therapy concepts are needed first and foremost. In addition, markers are pivotal to assign individual patients to a specific concept and to monitor the success of therapy. The main question is in which situation a neoadjuvant, perioperative or adjuvant radio-, chemo- or immunotherapy is superior. In fact, almost every curatively intended concept still contains surgical resection. Thus, improvement in surgical technique is also critical for multimodality concepts.

A Comprehensive Evaluation of Associations Between Routinely Collected Staging Information and The Response to (Chemo)Radiotherapy in Rectal Cancer

Simple Summary

Rectal cancer patients are often treated with radiotherapy, either alone or combined with chemotherapy, prior to surgery to enable radical surgery on a non-resectable tumor or to lower the recurrence risk. For some patients, the tumor disappears completely after preoperative treatment, while others experience little or no benefit. Accurate prediction of therapy response before treatment is of great importance for a personalized treatment approach and intentional organ preservation. We performed a comprehensive evaluation of the predictive capacity of all routinely collected staging information at diagnosis in a population-based, completely staged patient material of 383 patients representing a real-life clinical situation. Size or stage of the rectal tumor were independent predictors of excellent response irrespective of preoperative treatment, with small/early-stage tumors being significantly more likely to reach a complete response. Levels of the tumor marker carcinoembryonic antigen (CEA) above upper normal limit halved the chance of response.

Abstract

Radiotherapy (RT) or chemoradiotherapy (CRT) are frequently used in rectal cancer, sometimes resulting in complete tumor remission (CR). The predictive capacity of all clinical factors, laboratory values and magnetic resonance imaging parameters performed in routine staging was evaluated to understand what determines an excellent response to RT/CRT. A population-based cohort of 383 patients treated with short-course RT (5 × 5 Gy in one week, scRT), CRT, or scRT with chemotherapy (scRT+CT) and having either had a delay to surgery or been entered into a watch-and-wait program were included. Complete staging according to guidelines was performed and associations between investigated variables and CR rates were analyzed in univariate and multivariate analyses. In total, 17% achieved pathological or clinical CR, more often after scRT+CT and CRT than after scRT (27%, 18% and 8%, respectively, p < 0.001). Factors independently associated with CR included clinical tumor stage, small tumor size (<3 cm), tumor level, and low CEA-value (<3.8 μg/L). Size or stage of the rectal tumor were associated with excellent response in all therapy groups, with small or early stage tumors being significantly more likely to reach CR (p = 0.01 (scRT), p = 0.01 (CRT) and p = 0.02 (scRT+CT). Elevated level of carcinoembryonic antigen (CEA) halved the chance of response. Extramural vascular invasion (EMVI) and mucinous character may indicate less response to RT alone.

Exploring MR regression patterns in rectal cancer during neoadjuvant radiochemotherapy with daily T2- and diffusion-weighted MRI

Background

To date, only limited magnetic resonance imaging (MRI) data are available concerning tumor regression during neoadjuvant radiochemotherapy (RCT) of rectal cancer patients, which is a prerequisite for adaptive radiotherapy (RT) concepts. This exploratory study prospectively evaluated daily fractional MRI during neoadjuvant treatment to analyze the predictive value of MR biomarkers for treatment response.

Methods

Locally advanced rectal cancer patients were examined with daily MRI during neoadjuvant RCT. Contouring of the tumor volume was performed for each MRI scan by using T2- and diffusion-weighted-imaging (DWI)-sequences. The daily apparent-diffusion coefficient (ADC) was calculated. Volumetric and functional tumor changes during RCT were analyzed and correlated with the pathological response after surgical resection.

Results

In total, 171 MRI scans of eight patients were analyzed regarding anatomical and functional dynamics during RCT. Pathological complete response (pCR) could be achieved in four patients, and four patients had a pathological partial response (pPR) following neoadjuvant treatment. T2- and DWI-based volumetry proved to be statistically significant in terms of therapeutic response, and volumetric thresholds at week two and week four during RCT were defined for the prediction of pCR. In contrast, the average tumor ADC values widely overlapped between both response groups during RCT and appeared inadequate to predict treatment response in our patient cohort.

Conclusion

This prospective exploratory study supports the hypothesis that MRI may be able to predict pCR of rectal cancers early during neoadjuvant RCT. Our data therefore provide a useful template to tailor future MR-guided adaptive treatment concepts.

Organ-saving surgery for rectal cancer after neoadjuvant chemoradiation: Analysis of failures and long-term results

BACKGROUND

To analyze long-term results and risk of relapse in the clinical TNM stages II and III, mid-low rectal cancer patients (RC pts), treated with transanal local excision (LE) after major response to neoadjuvant chemoradiation (n-CRT).

METHODS

Thirty-two out of 345 extraperitoneal cT3-4 or N+ RC pts (9.3%) underwent LE.

INCLUSION CRITERIA

extraperitoneal RC, adenocarcinoma, ECOG Performance Status ≤2. Pts with distant metastases were excluded.

RESULTS

All pts showed histologically clear margins of resection and 81.2% were restaged ypT0/mic/1. Nine out of 32 (28.1%) pts relapsed: 7 (21.8%) showed a local recurrence, of which 5 (15.6%) at the endorectal suture, 1 (3.1%) pelvic and 1 (3.1%) mesorectal. Two pts (6.2%) relapsed distantly. Among the pT0/1, 11.5% relapsed vs 100% of the pT2 and pT4 ones. The six pts relapsing locally or in the mesorectal fat underwent a salvage total mesorectal excision surgery. The old patient with pelvic recurrence relapsed after 108 months and underwent a re-irradiation; the two pts with distant metastases were treated with chemotherapy followed by radical surgery.

CONCLUSIONS

Presently combined approach seems a valid option in major responders, confirming its potential curative impact in the ypT0/mic/1 pts. A strict selection of pts is basic to obtain favourable results.

Radiomics features on radiotherapy treatment planning CT can predict patient survival in locally advanced rectal cancer patients

This retrospective study was to investigate whether radiomics feature come from radiotherapy treatment planning CT can predict prognosis in locally advanced rectal cancer patients treated with neoadjuvant chemoradiation followed by surgery. Four-hundred-eleven locally advanced rectal cancer patients which were treated with neoadjuvant chemoradiation enrolled in this study. All patients’ radiotherapy treatment planning CTs were collected. Tumor was delineated on these CTs by physicians. An in-house radiomics software was used to calculate 271 radiomics features. The results of test-retest and contour-recontour studies were used to filter stable radiomics (Spearman correlation coefficient > 0.7). Twenty-one radiomics features were final enrolled. The performance of prediction model with the radiomics or clinical features were calculated. The clinical outcomes include local control, distant control, disease-free survival (DFS) and overall survival (OS). Model performance C-index was evaluated by C-index. Patients are divided into two groups by cluster results. The results of chi-square test revealed that the radiomics feature cluster is independent of clinical features. Patients have significant differences in OS (p = 0.032, log rank test) for these two groups. By supervised modeling, radiomics features can improve the prediction power of OS from 0.672 [0.617 0.728] with clinical features only to 0.730 [0.658 0.801]. In conclusion, the radiomics features from radiotherapy CT can potentially predict OS for locally advanced rectal cancer patients with neoadjuvant chemoradiation treatment.

The impact of total neo-adjuvant treatment on nonoperative management in patients with locally advanced rectal cancer: The evaluation of 66 cases

BACKGROUND

The study aimed to assess if adherence to a total-neoadjuvant-treatment (TNT) protocol followed by observation(watch-and-wait) led to the successful nonoperative-management of low-rectal-cancer.

METHODS

In this study, patients with primary, resectable-T3-T4, N0-N1 distal-rectal-adenocarcinoma underwent-chemoradiotherapy + consolidation-chemotherapy (TNT). During the-TNT-period, endoscopy, MRI, and FDG-PET/CT were performed. We allocated patients with complete-clinical-tumor-regression, who underwent endoscopy every two months, MRI every-four-months, and PET/CT every-six-months-after-treatment, to the observation-group(OG). All other patients were referred for surgery. The OG was followed-up. The primary endpoint was local tumor-ecurrence after allocation to the OG.

RESULTS

Between 2015 and 2018, we enrolled 66-patients. Of 60-patients who were eligible to participate, 39 had complete-clinical-response(cCR) and were allocated to the OG, six underwent local-excision (LE), and 15 underwent total-mesorectal-excision (TME). The median follow-up duration was 22 (9-42) months. The local-recurrence-rate in the OG was 15.3%, and the LE and TME rates were 16.6% and 0%, respectively. All recurrence cases were salvaged through either LE or TME. The-distant-metastasis rate was 5.1%, 16.6%, and 12.5% in the OG, LE, and TME groups, respectively. The endoscopic negative-predictive-value(NPV) was 50%, and the positive-predictive-value(PPV) was 76.9% in the surgery group (LE + TME). MRI; NPV-50%, PPV-76.9%. PET/CT; NPV-100%, PPV-93.3%. Six patients(28.57%) from surgery group achieved complete pathological response (cPR).

CONCLUSION

Our results indicated a high proportion of selected-rectal-cancers with-cCR after neo-adjuvant-therapy could potentially be managed non-operatively, and major surgery may be avoided.

Non-operative management of rectal cancer

Despite advances in technique, surgical resection of rectal cancer remains a morbid procedure that can lead a profound decrease in a patient's quality of life. A novel method of management, termed "Non-operative management" (NOM), mirrors the management of anal carcinoma. Patients undergo definitive treatment with only chemotherapy and radiation, with resection reserved only for salvage. Current data is encouraging- both in reduction in morbidity and similar, if not superior oncologic results. However, there are a number of barriers to the wide adoption of this practice. This manuscript seeks to describe the rationale and execution of NOM as well as present the current data and pitfalls of the approach.

'Watch and wait' in rectal cancer: summary of the current evidence

BACKGROUND

The management of rectal cancer has evolved considerably over the last few decades with increasing use of neoadjuvant chemoradiotherapy (nCRT). Complete clinical response (cCR) and even complete pathological response (pCR) have been noted in a proportion of patients who had surgery after nCRT. This raises the concern that we may have been 'over-treating' some of these patients and lead to an increasing interest in 'watch and wait' (W&W) approach for patients who had cCR to avoid the morbidity associated with rectal surgery.

METHODS

A review of the literature in English pertaining to rectal cancer in the context of W&W, organ preservation and active surveillance.

RESULTS

Evidence available to support W&W approach comes from non-randomised controlled trials (RCTs) with no current consensus on patients' selection criteria, lack of viable predictors of both cCR and pCR and lack of universal definitions of cCR and pCR. Also, there is no agreed protocol for disease surveillance.

CONCLUSION

Even though there has been increasing reports on the outcomes of W&W in rectal cancer, the current evidence cannot support its routine use in clinical practice. This approach should be used in clinical trials settings or after thorough counselling with the patient on the outcomes of various treatment options.

Robotic transanal minimally invasive surgery for rectal cancer after clinical complete response to neoadjuvant chemoradiation

BACKGROUND

Full-thickness local excision (FTLE) for rectal cancer showing clinical complete remission (cCR) after neoadjuvant chemoradiation therapy (NCRT) is associated with good oncological results. The purpose of this study was to report the results of robotic transanal minimally invasive surgery for such patients.

METHODS

Patients were treated with a 5-fluorouracil-based NCRT regimen. The determination of cCR was based on digital rectal examination, colonoscopy, and magnetic resonance imaging.

RESULTS

Six patients underwent transanal FTLE using the da Vinci Xi surgical system. The median operative time was 106.5 minutes, and the estimated blood loss was minimal. The mean length of hospital stay was 4.2 days. After 18.2 months of follow-up, none of the patients developed local recurrences or distant disease.

CONCLUSIONS

With the use of robotic technology, FTLE can be performed with relative ease and can be considered as a viable alternative to radical resection or a "Watch and Wait" strategy.

Decision-Making Strategy for Rectal Cancer Management Using Radiation Therapy for Elderly or Comorbid Patients

Rectal cancer predominantly affects patients older than 70 years, with peak incidence at age 80 to 85 years. However, the standard treatment paradigm for rectal cancer oftentimes cannot be feasibly applied to these patients owing to frailty or comorbid conditions. There are currently little information and no treatment guidelines to help direct therapy for patients who are elderly and/or have significant comorbidities, because most are not included or specifically studied in clinical trials. More recently various alternative treatment options have been brought to light that may potentially be utilized in this group of patients. This critical review examines the available literature on alternative therapies for rectal cancer and proposes a treatment algorithm to help guide clinicians in treatment decision making for elderly and comorbid patients.

Total Mesorectal Excision Versus Local Excision After Preoperative Chemoradiotherapy in Rectal Cancer With Lymph Node Metastasis: A Propensity Score-Matched Analysis

PURPOSE

To determine whether local excision (LE) outcomes were comparable to total mesorectal excision (TME) outcomes in node-positive (cN+) rectal cancer patients who were good responders.

METHODS AND MATERIALS

This retrospective study included clinical T2-3 and cN+ low rectal cancer patient who received preoperative chemoradiotherapy (PCRT) followed by TME or LE. Clinical stage T1 or T4 tumors, upper-to-middle rectal tumors (>7 cm from anal verge), and synchronous distant metastases were excluded. Lymph nodes ≥5 mm in size were defined as tumor-positive, and patients with metastatic lymph nodes >20 mm in size were excluded. Preoperative chemoradiotherapy comprised radiation (50-50.4 Gy/25-28 fractions over 5 weeks) with 2 cycles of 5-fluorouracil or oral capecitabine. Propensity scores were computed from tumor and patient variables and used for 1-to-1 matched analysis. Local recurrence-free survival, disease-free survival, and overall survival were compared between the 2 matched groups.

RESULTS

Between January 2007 and December 2013, 563 and 55 patients underwent TME and LE, respectively. The median follow-up period was 54 months. In propensity score-matched analysis, 48 patients were included in each group. No statistical differences were observed in 3-year local recurrence-free survival (97.9% vs 97.9%, P = .994), 3-year disease-free survival (91.5% vs 91.4%, P = .968), or 3-year OS (93.7% vs 97.9%, P = .809) between the TME and LE groups.

CONCLUSIONS

In clinical N+ rectal cancer patients, oncologic outcomes of PCRT followed by LE were comparable to those of TME; this finding might be applicable only to those patients with good response in the primary tumor and small lymph node metastases.

Wait-and-see treatment strategies for rectal cancer patients with clinical complete response after neoadjuvant chemoradiotherapy: a systematic review and meta-analysis

Wait-and-see treatment strategies may benefit rectal cancer patients who achieve a clinical complete response (cCR) after neoadjuvant chemoradiotherapy (NCRT). In this study, we analyzed data from 9 eligible trials to compare the oncologic outcomes of 251 rectal cancer patients achieving a cCR through nonsurgical management approaches with the outcomes of 344 patients achieving a pathologic complete response (pCR) through radical surgery. The two patient groups did not differ in distant metastasis rates or disease-free and overall survival, but the nonsurgical group had a higher risk of 1, 2, 3, and 5-year local recurrence. Hence, we concluded that for rectal cancer patients achieving a cCR after NCRT, a wait-and-see strategy with strict selection criteria, an appropriate follow-up schedule, and salvage treatments achieved outcomes at least as good as radical surgery. Long-term randomized and controlled trials with more uniform inclusion criteria and standardized follow-up schedules will help clarify the risks and benefits of wait-and-see treatment strategies for these patients.

Long-term outcomes in patients with ypT0 rectal cancer after neoadjuvant chemoradiotherapy and curative resection

Objective

For patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy (NCRT), significant pathological response of the primary tumor has been proposed to identify candidates for organ preservation. However, this does not address metastatic lymph nodes in the mesorectum. The aim of this study was to assess the incidence of lymph node metastases in ypT0 patients treated with NCRT and curative resection and to explore risk factors associated with survival.

Methods

This was a retrospective study of patients with ypT0 rectal cancer after NCRT and curative resection at a tertiary care center in China from 2005 to 2014.

Results

A total of 60 (18.6%) patients who underwent surgery after NCRT and achieved ypT0 were enrolled in this study; one patient was excluded owing to lack of follow-up. Of these 59 patients, lymph node metastases were found in the mesorectum (ypT0N+) in eight (13.6%) patients. After a median follow-up of 52 months, 5-year recurrence-free survival (82.7% vs. 62.5%, P=0.014) and overall survival (OS) (90.9% vs. 70.0%, P=0.032) were much higher in ypN0 than ypN+ patients. Multivariate analyses showed that ypN+ status (P=0.009) and perioperative blood transfusion (BT) (P=0.001) were significantly independent risk factors associated with recurrence; however, no factor was correlated with 5-year OS.

Conclusions

Patients with ypT0N0 rectal cancer can achieve excellent long-term outcomes; however, positive lymph nodes or tumor deposits can still be found in 13.6% of ypT0 patients. Nodal positivity in the mesorectum and perioperative BT are independent risk factors for recurrence.

Morphologic predictors of pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Purpose

To evaluate the value of morphological parameters that can be obtained conveniently by MRI for predicting pathologically complete response (pCR) in patients with rectal cancer.

Materials and Methods

A cohort of 101 patients was examined using MRI before and after Neoadjuvant chemoradiotherapy (nCRT). Morphological parameters including maximum tumor area (MTA), maximum tumor length (MTL) and maximum tumor thickness (MTT), as well as cylindrical approximated tumor volume (CATV), distance to anal verge (DTA), and the reduction rates were evaluated by two experienced readers independently.

Results

Post-nCRT MTA and MTL, reduction rates and pre-nCRT DTA were proved to be significantly different between pCR and non-pCR with the AUCs of 0.672-0.853. The sensitivity and specificity for assessing pCR were 61.1-89.9% and 59.0-80.7% respectively. No significant correlation between pre-nCRT size measurements and pCR was obtained.

Conclusion

The convenient morphological measurements may be useful for predicting pCR with moderate sensitivity and specificity. Combining these predictors with the aim of building diagnostic model should be explored.

Organ Preservation in Rectal Cancer After Chemoradiation: Should We Extend the Observation Period in Patients with a Clinical Near-Complete Response?

BACKGROUND

To assess whether extending the observation period in patients with a near clinical complete response (near cCR) after chemoradiation (CRT) leads to an impaired oncological outcome.

METHODS

Patients who had a clinical complete response (cCR) 8-10 weeks after CRT restaging with magnetic resonance imaging and endoscopy were offered a watch-and-wait strategy (W&W1), while patients with a near cCR were offered to undergo local excision or a second restaging 6-12 weeks later. Patients who achieved a cCR at the second restaging were also offered a watch-and-wait strategy (W&W2).

RESULTS

Overall, 102 patients with a cCR at the first restaging immediately entered the W&W1, while the remaining 68 patients had a near cCR: 19 patients underwent transanal endoscopic microsurgery and 49 patients opted for a second restaging. Additionally, 44/49 (90%) patients showed a cCR at the second restaging and entered the W&W2. Patients in the W&W1 group had a 2-year local regrowth-free rate (LRFR) of 84% and 2-year overall survival (OS) of 99%, while patients in the W&W2 group had a 2-year LRFR of 73% and OS of 98% (p > 0.05). Multivariable Cox regression analyses showed that late inclusion was not a significant predictive factor for higher risk of LR or lower non-regrowth disease-free survival.

CONCLUSIONS

Overall, 90% of patients with a near cCR 8-10 weeks after CRT will proceed to a cCR 6-12 weeks later; therefore, it seems logical to extend the observation period rather than to proceed to surgery. Although there is a non-significant increase in local regrowth rate in these patients, it does not seem to impact the oncological outcome.

Are We Predicting Disease Progress of the Rectal Cancer Patients without Surgery after Neoadjuvant Chemoradiotherapy?

Purpose

There are patients who do not undergo surgery, regardless of tumor response for neoadjuvant chemoradiotherapy (nCRT) in rectal cancer. However, there have been few reports focused on how oncologic outcomes are worse in these patients. We sought to investigate oncologic outcomes for these non-operated patients with rectal cancer after nCRT.

Materials and Methods

A total of 1,063 records of patients with rectal cancer who were treated with nCRT from January 2002 to December 2013 were retrospectively reviewed. We categorized patients into the non-operated group (n=77), transanal local excision (TLE) group (n=54), ortotal mesorectal excision (TME) group (n=932) and compared each group using propensity score matching.

Results

In the non-operated group, the most common reason for no surgery was patient refusal (n=64). Eleven patients were considered to have achieve clinical complete response (cCR), which was an independent prognostic factor of progression-free survival (p=0.045). In patients with disease progression in the non-operated group, the overall survival did not improved according to salvage treatments (p=0.451). The non-operated group showed worse survivals compared to the TLE or TME group before and after matching (p < 0.001). This finding was also noted in the analysis of survival only in patients with cCR.

Conclusion

In this study, non-operated patients did not secure oncologic safety regardless of cCR after nCRT. Our results suggest that a non-operative management must be carefully considered even if cCR is achieved.

Total Mesorectal Excision Versus Local Excision After Favorable Response to Preoperative Chemoradiotherapy in "Early" Clinical T3 Rectal Cancer: A Propensity Score Analysis

PURPOSE

To compare oncological outcomes of total mesorectal excision (TME) and local excision (LE) in patients with "early" clinical T3 rectal cancer who received preoperative chemoradiotherapy (PCRT).

METHODS AND MATERIALS

"Early" clinical T3 rectal cancer was radiologically defined as tumors with extramural extension of <5 mm without mesorectal fascia involvement and lateral lymph node metastasis. Patients with "early" clinical T3 rectal cancer who received PCRT followed by TME or LE between January 2007 and December 2013 were retrospectively analyzed. Propensity scores were generated using patient and tumor characteristics, and a one-to-one case-matched analysis was conducted. Local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) were compared between the TME and LE groups.

RESULTS

Of the 406 enrolled patients, 351 received TME and 55 received LE. The median follow-up period was 45 months. Following propensity score matching, each group contained 55 patients. Among 103 patients evaluable for pathologic tumor response, 82 patients (79.6%) showed complete response or near-complete response. No significant differences were observed between the TME and LE groups in LRFS (3-year LRFS 98.1% vs 94.4%, P=.312), DFS (3-year DFS 92.1% vs 90.8%, P=.683), and OS (3-year OS 98.2% vs 100.0%, P=.895).

CONCLUSIONS

In "early" clinical T3 rectal cancer, PCRT followed by LE showed comparable oncologic outcomes to TME. Because most of the matched cohort consisted of good responders to PCRT, the present results should be applied to a limited population.

On a prolonged interval between rectal cancer (chemo)radiotherapy and surgery

Preoperative radiotherapy (RT) or chemoradiotherapy (CRT) is often required before rectal cancer surgery to obtain low local recurrence rates or, in locally advanced tumours, to radically remove the tumour. RT/CRT in tumours responding completely can allow an organ-preserving strategy. The time from the end of the RT/CRT to surgery or to the decision not to operate has been prolonged during recent years. After a brief review of the literature, the relevance of the time interval to surgery is discussed depending upon the indication for RT/CRT. In intermediate rectal cancers, where the aim is to decrease local recurrence rates without any need for down-sizing/-staging, short-course RT with immediate surgery is appropriate. In elderly patients at risk for surgical complications, surgery could be delayed 5-8 weeks. If CRT is used, surgery should be performed when the acute radiation reaction has subsided or after 5-6 weeks. In locally advanced tumours, where CRT is indicated, the optimal delay is 6-8 weeks. In patients not tolerating CRT, short-course RT with a 6-8-week delay is an alternative. If organ preservation is a goal, a first evaluation should preferably be carried out after about 6 weeks, with planned surgery for week 8 if the response is inadequate. In case the response is good, a new evaluation should be carried out after about 12 weeks, with a decision to start a 'watch-and-wait' programme or operate. Chemotherapy in the waiting period is an interesting option, and has been the subject of recent trials with promising results.

Non-surgical management of rectal cancer. Series of 68 cases, long follow up in two leading centres in Argentina

BACKGROUND

The non-surgical management in a selected group of rectal cancer patients has shown promising results with adequate follow up.

AIMS

describing the results of the non-surgical management in patients with complete clinical response, with a close follow up.

METHODS

Between 2006 and 2015, patients with rectal cancer, stages I-III, without metastasis, treated with neoadjuvant CRT/CT, who had clinical complete response were included. CCR was defined through digital palpation, endoscopy-based criteria and MRI. Follow up was set according to institutional guidelines.

RESULTS

68 patients were included. Initial stage was assessed with MRI in 55/68 pts and EUS 11/68. Considering the recurrence risk factors 57.6% (29/68) were T2-3ab N0, 3.3% (2/68) were T4N0, 29% (20/68) were T3-4 N1-2, with 39.7% with positive MRC. Mean distance to the anal margin was 3cm. Chemoradiation included radiotherapy at 50.4cGy, and concurrent capecitabine. In 22% a fluoropirimidine and oxaliplatin-based schema was used as induction therapy. Median follow up was 37.5 months and response assessment time 9 weeks (5-19). Eleven patients recurred, 6 endoluminally, 3 developed mesorectal recurrence, and two distant failure. Five years DFS and OS were 76.3% and 93.8%.

CONCLUSIONS

conservative management was feasible with close follow up in leading cancer centres. In this series, DFS and OS were comparable to the data already reported in the literature.

High nodal positivity rates even in good clinical responders after chemoradiation of rectal cancer: is organ preservation feasible?

AIM

Local excision (LE) is emerging as a treatment option for rectal cancer responding well to chemoradiation. However, it does not address the mesorectal nodal burden. We aimed to identify the factors influencing nodal positivity and subsequently defined a low-risk group by including only patients at low risk.

METHOD

A single-centre, retrospective database analysis was carried out of patients with radically resected rectal cancer after neoadjuvant chemoradiation.

RESULTS

This study included 524 patients with predominantly low rectal tumours. Nodal positivity among ypT0, T1 and T2 groups was 14.7%, 28% and 30%, respectively. Multivariate analysis with stepwise logistic regression identified the following low-risk features: age ≥ 40 years, nonsignet ring cell carcinoma (SRCC) histology and pathological complete response (pCR). Sixty-nine patients fulfilling all three criteria were analysed and the nodal positivity was found to be 10.1%, which implies that, if these patients had been selected for LE, one in 10 would have had positive mesorectal nodes.

CONCLUSION

Even in patients with low-risk criteria (pCR, non-SRCC histology and age ≥ 40 years), the residual positive nodal disease burden is 10%. Whether this high incidence of residual nodal disease translates into a similar risk of locoregional recurrence if an organ-preservation strategy is adopted is unclear.

Watch-and-wait approach versus surgical resection after chemoradiotherapy for patients with rectal cancer (the OnCoRe project): a propensity-score matched cohort analysis

BACKGROUND

Induction of a clinical complete response with chemoradiotherapy, followed by observation via a watch-and-wait approach, has emerged as a management option for patients with rectal cancer. We aimed to address the shortage of evidence regarding the safety of the watch-and-wait approach by comparing oncological outcomes between patients managed by watch and wait who achieved a clinical complete response and those who had surgical resection (standard care).

METHODS

Oncological Outcomes after Clinical Complete Response in Patients with Rectal Cancer (OnCoRe) was a propensity-score matched cohort analysis study, that included patients of all ages diagnosed with rectal adenocarcinoma without distant metastases who had received preoperative chemoradiotherapy (45 Gy in 25 daily fractions with concurrent fluoropyrimidine-based chemotherapy) at a tertiary cancer centre in Manchester, UK, between Jan 14, 2011, and April 15, 2013. Patients who had a clinical complete response were offered management with the watch-and-wait approach, and patients who did not have a complete clinical response were offered surgical resection if eligible. We also included patients with a clinical complete response managed by watch and wait between March 10, 2005, and Jan 21, 2015, across three neighbouring UK regional cancer centres, whose details were obtained through a registry. For comparative analyses, we derived one-to-one paired cohorts of watch and wait versus surgical resection using propensity-score matching (including T stage, age, and performance status). The primary endpoint was non-regrowth disease-free survival from the date that chemoradiotherapy was started, and secondary endpoints were overall survival, and colostomy-free survival. We used a conservative p value of less than 0·01 to indicate statistical significance in the comparative analyses.

FINDINGS

259 patients were included in our Manchester tertiary cancer centre cohort, 228 of whom underwent surgical resection at referring hospitals and 31 of whom had a clinical complete response, managed by watch and wait. A further 98 patients were added to the watch-and-wait group via the registry. Of the 129 patients managed by watch and wait (median follow-up 33 months [IQR 19-43]), 44 (34%) had local regrowths (3-year actuarial rate 38% [95% CI 30-48]); 36 (88%) of 41 patients with non-metastatic local regrowths were salvaged. In the matched analyses (109 patients in each treatment group), no differences in 3-year non-regrowth disease-free survival were noted between watch and wait and surgical resection (88% [95% CI 75-94] with watch and wait vs 78% [63-87] with surgical resection; time-varying p=0·043). Similarly, no difference in 3-year overall survival was noted (96% [88-98] vs 87% [77-93]; time-varying p=0·024). By contrast, patients managed by watch and wait had significantly better 3-year colostomy-free survival than did those who had surgical resection (74% [95% CI 64-82] vs 47% [37-57]; hazard ratio 0·445 [95% CI 0·31-0·63; p<0·0001), with a 26% (95% CI 13-39) absolute difference in patients who avoided permanent colostomy at 3 years between treatment groups.

INTERPRETATION

A substantial proportion of patients with rectal cancer managed by watch and wait avoided major surgery and averted permanent colostomy without loss of oncological safety at 3 years. These findings should inform decision making at the outset of chemoradiotherapy.

FUNDING

Bowel Disease Research Foundation.

Oncologic Outcomes according to the Treatment Strategy in Radiologic Complete Responders after Neoadjuvant Chemoradiation for Rectal Cancer

OBJECTIVE

This study aimed to compare the oncologic outcomes between treatment strategies for rectal cancer [radical surgery, local excision (LE), and the wait-and-see approach] in radiologic complete responders after neoadjuvant chemoradiation (nCRT).

METHODS

We retrospectively reviewed rectal cancer patients and included 52 radiologic complete responders after nCRT defined as no residual tumor or residual fibrosis and no suspicious metastatic lymph nodes on magnetic resonance imaging (MRI). Clinicopathologic features and oncologic outcomes were compared according to the treatment strategies.

RESULTS

The median follow-up period was 41 months (range, 6-80). Twenty-eight patients underwent radical surgery, whereas 16 underwent LE, and 8 were closely monitored without initial surgery. The pathologic complete response rate was 40.9%. Patients who underwent radical surgery showed better prognosis compared to those who underwent LE or wait-and-see (3-year disease-free survival: radical surgery 85.0% vs. LE 62.5%, wait-and-see 75.0%, p = 0.019; 3-year local recurrence-free survival: radical surgery 96.4% vs. LE 67.0%, wait-and-see 75.0%, p = 0.009). After recurrence, patients who underwent salvage surgery showed a relatively good oncologic outcome.

CONCLUSION

Pursuing LE or the wait-and-see approach instead of radical surgery in rectal cancer patients undergoing nCRT may bring about a detrimental oncologic outcome if clinical complete response is solely determined by MRI.

Comparison of the pathological response of the mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery and long-course chemoradiotherapy in patients with rectal cancer

BACKGROUND

The aim of this study was to compare the pathological response of mesorectal positive nodes between short-course chemoradiotherapy with delayed surgery (SCRT-delay) and long-course chemoradiotherapy (LC-CRT) in patients with rectal cancer.

METHOD

The resected primary tumor specimens following the two different approaches were assessed utilizing the tumor regression grade (TRG 0-4), and each positive lymph node was assessed according to the lymph node regression grade (LRG 1-3), with TRG 4 and LRG 3 indicating total regression. The lymph node sizes were measured to elucidate any correlation with LRG scores.

RESULTS

Seventy-four patients with ypN-positive rectal cancer had 220 positive lymph nodes following the SCRT-delay, and 48 patients had 141 positive lymph nodes following the LC-CRT. The distribution of LRG 1/2/3 in the two groups was 123/72/25 and 60/31/50 (p < 0.001), respectively, and the distribution of TRG 0/1/2/3/4 in the two groups was 36/19/19/0 and 12/15/20/1 (p = 0.005), respectively. The requirements of total regression of positive lymph nodes were a primary tumor degenerated to TRG 3 with a size less than 6 mm in SCRT-delay (sensitivity, 60.9 %) or a primary tumor degenerated to TRG 2-4 with a size less than 5 mm at TRG 2 (sensitivity, 57.6 %) or 6 mm at TRG 3 and 4 (sensitivity, 84.2 %) in LC-CRT as indicated by the receiver operating characteristic curve analysis.

CONCLUSION

The tumor regression effect of LC-CRT on the primary tumor and positive nodes was more favorable than SCRT-delay, and LC-CRT is able to predict the LRG 3 response with a high sensitivity.

[Organ preserving strategies for rectal cancer treatment]

For rectal cancers, the current standard of care consists of chemoradiation followed by radical surgery with total mesorectal excision. Oncologic results are good, especially regarding local recurrence rates, but at the cost of high morbidity rates and poor anorectal, urinary and sexual function results. Since chemoradiation yields 15 to 25% pathological complete response, the role of radical surgery is questioned for patients presenting with good response after chemoradiation and two organ preservation strategies have been offered: watch and wait strategy and local excision strategy. The aim of this review is to give the results of organ preservation after chemoradiotherapy series and to highlight different questions regarding initial patient's selection, complete clinical response definition, risk of mesorectal nodal involvement, follow-up modalities as well as oncologic and functional results.

Organ preservation in rectal cancer: current status and future perspectives

With the introduction of population screening initiatives, more patients may be amenable to local, transanal excision (LE) of early-stage rectal cancer. The most important drawback of LE is the risk of understaging node-positive disease. The most powerful predictors of node-positive disease are lymphatic invasion, submucosal invasion depth and width, tumor budding and poor differentiation. Therefore, LE should be reserved for low-risk T1 tumors in those reluctant or unable to undergo major surgery. Neoadjuvant chemoradiation followed by LE for T2 tumors allows adequate local control, and is currently being compared with anterior resection alone in randomized trials. A mere watchful waiting approach has been proposed in clinical complete responders to chemoradiation. However, given the very poor accuracy of current imaging modalities to predict a true pathological complete response, this strategy should not be offered outside of well-controlled trials.

Local excision for early rectal cancer: transanal endoscopic microsurgery and beyond

The goal of treatment for early stage rectal cancer is to optimize oncologic control while minimizing the long-term impact of treatment on quality of life. The standard of care treatment for most stage I and II rectal cancers is radical surgery alone, specifically total mesorectal excision (TME). For early rectal cancers, this procedure is usually curative but can have a substantial impact on quality of life, including the possibility of permanent colostomy and the potential for short and long-term bowel, bladder, and sexual dysfunction. Given the morbidity associated with radical surgery, alternative approaches to management of early rectal cancer have been explored, including local excision (LE) via transanal excision (TAE) or transanal endoscopic microsurgery (TEM) and transanal minimally invasive surgery (TAMIS). Compared to the gold standard of radical surgery, local procedures for strictly selected early rectal cancers should lead to identical oncological results and even better outcomes regarding morbidity, mortality, and quality of life.

Organ preservation in rectal cancer: have all questions been answered?

Improved treatment strategies have eliminated local control as the major problem in rectal cancer. With increasing awareness of long-term toxic effects in survivors of rectal cancer, organ-preservation strategies are becoming more popular. After chemoradiotherapy, both watchful waiting and local excision are used as possible alternatives for radical surgery. Although these seem attractive strategies, many issues about the safety of organ preservation remain. Additionally, radiotherapy strategies are mainly aimed at intermediate and high-risk rectal tumours, and adaptation of this standard practice for a completely new treatment indication has yet to start. This Review will discuss the options and problems of organ preservation, and address the research questions that need to be answered in the coming years, with a specific focus on radiotherapy.

Clinical tumour size and nodal status predict pathologic complete response following neoadjuvant chemoradiotherapy for rectal cancer

PURPOSE

Pathologic complete response (pCR) to neoadjuvant treatment for rectal cancer has been associated with improved local control, reduced distant disease and a survival advantage when compared with non-complete responders. Approximately 10-25 % of patients undergoing neoadjuvant chemoradiotherapy for rectal cancer achieve pCR; however, predictors for its occurrence are inadequately defined. This study aimed to identify clinical and tumour factors that predict pCR in patients receiving neoadjuvant chemoradiotherapy for rectal cancer.

METHODS

Consecutive rectal cancer patients diagnosed and treated in the Auckland region between 1 January 2002 and 1 February 2013 were retrospectively identified. Cases were stratified by the occurrence of pCR or non-pCR. Predictive capacity of several patient, tumour and treatment-related variables were then assessed by univariate and regression analyses.

RESULTS

Two hundred ninety-seven patients received neoadjuvant chemoradiotherapy, of whom 34 (11.4 %) achieved pCR. There were no significant differences in age, gender, ethnicity, BMI, pretreatment clinical T or N stage, tumour distance from the anal verge, tumour differentiation, chemoradiotherapy regimen and time interval to surgery between the pCR and non-pCR groups. Univariate analysis identified pretreatment serum CEA levels, a reduction in pre- to post-treatment serum CEA and smaller tumours as significant correlates of pCR. Logistic regression analysis found smaller tumour size and pretreatment clinical N stage as independent clinical predictors for achieving pCR.

CONCLUSIONS

Smaller tumour size and pretreatment clinical N stage were independent clinical predictors for achieving pCR. Prospective analysis is recommended for more rigorous risk factor assessment.

Current issues in locally advanced colorectal cancer treated by preoperative chemoradiotherapy

In patients with locally advanced rectal cancer, preoperative chemoradiotherapy has proven to significantly improve local control and cause lower treatment-related toxicity compared with postoperative adjuvant treatment. Preoperative chemoradiotherapy followed by total mesorectal excision or tumor specific mesorectal excision has evolved as the standard treatment for locally advanced rectal cancer. The paradigm shift from postoperative to preoperative therapy has raised a series of concerns however that have practical clinical implications. These include the method used to predict patients who will show good response, sphincter preservation, the application of conservative management such as local excision or “wait-and-watch” in patients obtaining a good response following preoperative chemoradiotherapy, and the role of adjuvant chemotherapy. This review addresses these current issues in patients with locally advanced rectal cancer treated by preoperative chemoradiotherapy.

Evolving treatment strategies for colorectal cancer: A critical review of current therapeutic options

Management of rectal cancer has markedly evolved over the last two decades. New technologies of staging have allowed a more precise definition of tumor extension. Refinements in surgical concepts and techniques have resulted in higher rates of sphincter preservation and better functional outcome for patients with this malignancy. Although, preoperative chemoradiotherapy followed by total mesorectal excision has become the standard of care for locally advanced tumors, many controversial matters in management of rectal cancer still need to be defined. These include the feasibility of a non-surgical approach after a favorable response to neoadjuvant therapy, the ideal margins of surgical resection for sphincter preservation and the adequacy of minimally invasive techniques of tumor resection. In this article, after an extensive search in PubMed and Embase databases, we critically review the current strategies and the most debatable matters in treatment of rectal cancer.

Future directions for monitoring treatment response in colorectal cancer

Treatment of advanced colon and rectal cancer has significantly evolved with the introduction of neoadjuvant chemoradiation therapy so much that, along with more effective chemotherapy regimens, surgery has been considered unnecessary among some institutions for select patients. The tumor response to these treatments has also improved and ultimately has been shown to have a direct effect on prognosis. Yet, the best way to monitor that response, whether clinically, radiologically, or with laboratory findings, remains controversial. The authors' aim is to briefly review the options available and, more importantly, examine emerging and future options to assist in monitoring treatment response in cases of locally advanced rectal cancer and metastatic colon cancer.

Neo-adjuvant radiotherapy in rectal cancer

In rectal cancer treatment, attention has focused on the local primary tumour and the regional tumour cell deposits to diminish the risk of a loco-regional recurrence. Several large randomized trials have also shown that combinations of surgery, radiotherapy and chemotherapy have markedly reduced the risk of a loco-regional recurrence, but this has not yet had any major influence on overall survival. The best results have been achieved when the radiotherapy has been given preoperatively. Preoperative radiotherapy improves loco-regional control even when surgery has been optimized to improve lateral clearance, i.e., when a total mesorectal excision has been performed. The relative reduction is then 50%-70%. The value of radiotherapy has not been tested in combination with more extensive surgery including lateral lymph node clearance, as practised in some Asian countries. Many details about how the radiotherapy is performed are still open for discussion, and practice varies between countries. A highly fractionated radiation schedule (5 Gy × 5), proven efficacious in many trials, has gained much popularity in some countries, whereas a conventionally fractionated regimen (1.8-2.0 Gy × 25-28), often combined with chemotherapy, is used in other countries. The additional therapy adds morbidity to the morbidity that surgery causes, and should therefore be administered only when the risk of loco-regional recurrence is sufficiently high. The best integration of the weakest modality, to date the drugs (conventional cytotoxics and biologicals) is not known. A new generation of trials exploring the best sequence of treatments is required. Furthermore, there is a great need to develop predictors of response, so that treatment can be further individualized and not solely based upon clinical factors and anatomic imaging.

Non-operative management for locally advanced rectal cancer: critical review and future perspective

SUMMARY Over the last few decades we have observed important advances in diagnostic imaging, surgery, pathology and multimodal treatments for rectal cancer, as well as increased efforts to reduce treatment-related toxicities and preserve quality of life for curatively treated patients. Neoadjuvant short-course radiotherapy and long-course chemoradiotherapy followed by total mesorectal excision remain widely accepted as the standard of care for patients with locally advanced rectal cancer. However, a carefully selected group of patients achieving a complete response to neoadjuvant chemoradiotherapy may be spared the effects of surgery and achieve satisfactory oncologic outcomes with a ‘wait-and-see’ strategy. Although supported by the results of previous studies, this intriguing paradigm shift needs prospective evaluation within a clinical trial setting and a more accurate prediction and assessment of response by means of tumor biomarkers and diagnostic imaging.

Definitive radical external beam radiotherapy for rectal cancer: evaluation of local effectiveness and risk of late small bowel damage

AIM

To present a retrospective analysis of results of definitive radiotherapy for rectal cancer.

MATERIAL AND METHODS

Forty-one consecutive patients with rectal cancer (32% primary, 61% pelvic recurrence and 7% after R2 resection) who could not be treated with surgery underwent external beam radiotherapy. A median tumour dose of 64 Gy was given with 1.8-2.5 Gy per fraction using 2D or 3D technique. In 46% of patients, concurrent 5-Fu-based chemotherapy was given. The median follow-up was 54 months.

RESULTS

Clinical complete response was achieved in 39% of patients. Five-year cumulative incidence of local failure, overall survival and cancer specific survival were 76%, 26% and 30%, respectively. Of 11 patients with local control, in five cases the tumour was larger than 5 cm and in the other five the tumour was fixed. Two patients, regarded as locally controlled had non-progressive tumour without local symptoms at the last follow-up of 54 and 118 months post-radiotherapy. Late toxicity occurred in 22% of patients, all with acceptable severity. There was no bowel obstruction requiring surgery despite that in 18 patients the small bowel dose was >60 Gy to a mean volume of 51 cm(3).

CONCLUSION

Definitive radio(chemo)therapy provides a chance for local control even in patients with large fixed or recurrent rectal cancer.