Comparison of short course radiotherapy with chemoradiotherapy for locally advanced rectal cancers in the elderly: A multicentre, randomised, non-blinded, phase 3 trial

Organ preservation, for rectal cancer: general overview of the latest data from phase III randomized trials

INTRODUCTION

Organ preservation (OP) strategies are gaining interest in improving the quality of life in the management of rectal cancer, particularly for tumors located in the distal or middle rectum. The optimal OP protocol is still not standardized and relies on randomized trials. This review summarizes past and ongoing studies on OP protocols for adenocarcinoma of the distal and middle rectum.

METHOD

We searched for articles and abstracts on randomized clinical trials investigating OP approaches for rectal cancer, including data presented at the LUCARRE Congress held in Nice on November 25, 2023, covering ongoing and recently published trials on rectal preservation.

RESULTS

Our review's findings are presented in four tables: the first evaluates key trials with overall survival (OS) as the primary endpoint; the second provides an overview of past Phase III trials; the third reviews Phase II/III trials that specifically focus on local excisions (LE); and finally, the fourth summarizes ongoing trials. Each table is accompanied by detailed comments elucidating the significance and implications of the presented data, alongside a review of current guidelines.

INTERPRETATION

We highlight the growing interest in OP strategies for rectal cancer management to enhance patients' quality of life. Despite the lack of international consensus on the optimal OP protocol, past and ongoing randomized trials provide valuable findings into the evolving management strategies of rectal cancer treatment. The presented data supports the role of randomized phase III trials to provide evidence for a change in clinical practice.

Efficacy of Neoadjuvant Hypofractionated Chemoradiotherapy in Elderly Patients with Locally Advanced Rectal Cancer: A Single-Center Retrospective Analysis

Background/Objectives: The application of long-course chemoradiotherapy (LCRT) in elderly patients with locally advanced rectal cancer (LARC) can be challenging due to increased risks of complications associated with comorbidities and reduced functional status. This study aimed to assess the efficacy of neoadjuvant hypofractionated chemoradiotherapy (HCRT) in elderly patients with mid-to-low LARC. Methods: We performed a retrospective review of patients diagnosed with LARC from January 2013 to December 2020 and included those aged 70 years or older. Patients were categorized into three groups based on their treatment strategies: neoadjuvant HCRT (33 or 35 Gy in 10 fractions), neoadjuvant LCRT, and upfront surgery. Comparative analyses were performed on clinicopathological characteristics, short-term outcomes, and long-term survival outcomes among these groups. Results: Among the 296 patients included, 30 (10.1%) received HCRT, 195 (65.9%) underwent standard LCRT, and 71 (24.0%) underwent upfront surgery. The baseline characteristics showed that the HCRT group had a higher American Society of Anesthesiologists (ASA) score (ASA score 3 or 4, HCRT 43.3% vs. LCRT 16.9% vs. upfront surgery 15.5%, p = 0.002). The HCRT group showed a significantly lower incidence of radiotherapy-related complications than the LCRT group (16.7% vs. 48.7%, p = 0.001). However, the rate of pathological complete response was significantly lower in the HCRT group (10.0% vs. 15.4%, p = 0.002). The 3-year relapse-free survival (83.0% vs. 77.2% vs. 83.2%; p = 0.411), 3-year local recurrence-free survival (93.1% vs. 93.2% vs. 93.5%; p = 0.464), and 5-year overall survival (65.1% vs. 67.0% vs. 67.7%; p = 0.682) were not significantly different between the three groups. Multivariate analysis also showed that the treatment strategy was not associated with survival outcomes. Conclusions: Neoadjuvant HCRT demonstrated reduced radiotherapy-related complications and acceptable long-term oncologic outcomes. Therefore, neoadjuvant HCRT may be considered as a viable alternative for elderly patients with LARC.

ResNet-Vision Transformer based MRI-endoscopy fusion model for predicting treatment response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer: A multicenter study

Background:

Neoadjuvant chemoradiotherapy followed by radical surgery has been a common practice for patients with locally advanced rectal cancer, but the response rate varies among patients. This study aimed to develop a ResNet-Vision Transformer based magnetic resonance imaging (MRI)-endoscopy fusion model to precisely predict treatment response and provide personalized treatment.

Methods:

In this multicenter study, 366 eligible patients who had undergone neoadjuvant chemoradiotherapy followed by radical surgery at eight Chinese tertiary hospitals between January 2017 and June 2024 were recruited, with 2928 pretreatment colonic endoscopic images and 366 pelvic MRI images. An MRI-endoscopy fusion model was constructed based on the ResNet backbone and Transformer network using pretreatment MRI and endoscopic images. Treatment response was defined as good response or non-good response based on the tumor regression grade. The Delong test and the Hanley–McNeil test were utilized to compare prediction performance among different models and different subgroups, respectively. The predictive performance of the MRI-endoscopy fusion model was comprehensively validated in the test sets and was further compared to that of the single-modal MRI model and single-modal endoscopy model.

Results:

The MRI-endoscopy fusion model demonstrated favorable prediction performance. In the internal validation set, the area under the curve (AUC) and accuracy were 0.852 (95% confidence interval [CI]: 0.744–0.940) and 0.737 (95% CI: 0.712–0.844), respectively. Moreover, the AUC and accuracy reached 0.769 (95% CI: 0.678–0.861) and 0.729 (95% CI: 0.628–0.821), respectively, in the external test set. In addition, the MRI-endoscopy fusion model outperformed the single-modal MRI model (AUC: 0.692 [95% CI: 0.609–0.783], accuracy: 0.659 [95% CI: 0.565–0.775]) and the single-modal endoscopy model (AUC: 0.720 [95% CI: 0.617–0.823], accuracy: 0.713 [95% CI: 0.612–0.809]) in the external test set.

Conclusion:

The MRI-endoscopy fusion model based on ResNet-Vision Transformer achieved favorable performance in predicting treatment response to neoadjuvant chemoradiotherapy and holds tremendous potential for enabling personalized treatment regimens for locally advanced rectal cancer patients.

Comprehensive geriatric assessment guided radiotherapy in elderly patients with locally advanced rectal cancer-exploratory results on nonoperative cohort of a multicenter prospective study

Background

Chemoradiotherapy (CRT) is the main treatment for elderly patients with non-metastatic rectal cancer who are ineligible for or decline surgery, but the optimal modality remains unclear.

Objectives

This study was to validate the safety and efficacy of comprehensive geriatric assessment (CGA) guided radiotherapy in older patients.

Design

An exploratory analysis of a single-arm, multicenter, Phase II trial.

Methods

Patients aged over 70 and diagnosed with rectal cancer were enrolled and evaluated by CGA. CGA-guided radiotherapy was individually conducted in a multidisciplinary setting. Patients in fit, intermediate, and frail groups were scheduled to receive CRT, long-course radiotherapy, and short-course radiotherapy (SCRT) alone respectively. Patients who were unfit for or refused surgery were analyzed for acute toxicities and survival outcomes.

Results

In a total of 109 enrolled patients, 47 individuals who did not undergo surgery were included, with 26, 9, and 12 categorized into fit, intermediate, and frail groups. Only 11 (23.4%) grade 3 or above toxicities were observed overall. Within a median follow-up of 69.0 months, the 3-year overall survival (OS), progression-free survival (PFS), and cancer-specific survival (CSS) rates were 44.3% (95% CI: 32.1%-61.2%), 25.5% (95% CI: 15.7%-41.6%) and 61.0% (95% CI: 47.8%-77.6%) in total. The 5-year OS, PFS, and CSS reached 15.0% (95% CI: 7.4%-30.3%), 14.6% (95% CI: 7.3%-29.4%), and 36.2% (95% CI: 22.0%-59.4%), with no significant difference among the three subgroups. SCRT (p < 0.001) and dose boost (p = 0.045) contributed to lower tumor-related death rates in multiple competing risk regressions.

Conclusion

Radiotherapy guided by CGA was effective and well-tolerated in non-surgical elderly patients. SCRT alone seemed to achieve similar clinical outcomes as CRT in corresponding subgroups. However, given the limited size of this study, further investigation in a larger population is still needed for this strategy.

[Practice-changing clinical trials in gastrointestinal radiation oncology]

Current events in radiotherapy oncology are marked by the results of strategic trials, particularly for esophageal and rectal cancers. For resectable esophageal adenocarcinoma, results of the ESOPEC study showed a benefit in overall survival from the perioperative chemotherapy with fluorouracil plus leucovorin, oxaliplatin and docetaxel compared to chemoradiotherapy (41.4Gy radiotherapy and carboplatin/paclitaxel chemotherapy). In definitive setting, the CONCORDE study did not show any benefit from dose escalation and the standard dose remains 50Gy. For resectable pancreatic cancer, the NRG/RTOG0848 study that compared adjuvant chemotherapy with or without chemoradiotherapy found a significant increase of the 5-year disease-free survival rate in the subgroup of node-negative patients. For rectal cancers, the 7-year update of PRODIGE 23 study confirmed the benefit in disease-free- and overall survival of neoadjuvant folinic acid, fluorouracil, irinotecan and oxaliplatin chemotherapy before chemoradiotherapy of T3, T4 or N+ adenocarcinoma, while the update of the RAPIDO study revealed an unacceptable local recurrence rate in the experimental arm. The update of the OPRA study shows a significantly higher 5-year organ preservation rate in favor of the chemoradiotherapy arm followed by consolidation chemotherapy compared to induction chemotherapy followed by CRT. A phase 2 study, including 41 patients with mismatch repair deficient, locally advanced rectal cancer reported that exclusive treatment with anti-PDL1 immunotherapy (dostarlimab) for 6 months resulted in complete clinical response without the need of additional treatment (neither radiotherapy nor surgery). For anal carcinoma, the analysis of survival and toxicity profiles of patients treated for a small stage T1 or T2 tumor were compared depending on whether they received exclusive radiotherapy or chemoradiotherapy. The addition of chemotherapy to radiotherapy did not show any survival benefit but significantly increased toxicity and the risk of radiotherapy disruption.

Treatment approaches and survival outcomes in elderly colorectal cancer patients: a single-center comparative study

BACKGROUND

Geriatric patients account for nearly half of new colorectal cancer (CRC) cases. This study compares clinicopathological features, treatments, outcomes, and frailty in elderly (≥ 70) and younger (< 70) CRC patients at our center.

MATERIALS AND METHODS

Patients diagnosed with non-metastatic or de novo metastatic CRC between January 2015 and April 2024 were included. Demographic, pathological, and survival data were retrospectively collected. Analyses were performed using SPSS version 25, with statistical significance set at P < 0.05.

RESULTS

Of the 414 non-metastatic CRC patients, 26.6% were aged ≥ 70. Elderly patients received less perioperative chemotherapy (60% vs. 81.6%, P < 0.001) and had more dose reductions (41.6% vs. 19.2%, P < 0.001). Frailty reduced perioperative chemotherapy in elderly non-metastatic patients (54.5% vs. 92.1%, P < 0.001) but did not affect dose reduction (37.9% vs. 33.3%, P = 0.764) or treatment duration (median 24 weeks for both groups, P = 0.909). In metastatic patients, frailty shortened chemotherapy duration (9.5 vs. 15.5 weeks, P = 0.129). Elderly patients had lower 5- and 8-year overall survival (OS) rates (64.7%, 60.1% vs. 83.0%, 78.8%, P = 0.004). In the de novo metastatic cohort (135 patients), age did not affect OS (19.4 vs. 17.3 months, P = 0.590) or PFS (9.8 vs. 7.5 months, P = 0.209). Rectal cancer (HR: 2.751, P = 0.005) and early chemotherapy termination (HR: 4.138, P < 0.001) worsened OS in non-metastatic CRC, while absence of RAS (HR: 2.043, P = 0.047), BRAF mutations (HR: 8.263, P = 0.010), and metastasectomy (HR: 3.650, P = 0.036) improved OS in metastatic CRC.

CONCLUSION

Age does not independently worsen CRC survival, though early chemotherapy discontinuation impacts outcomes. Reduced-dose chemotherapy or monotherapy can help minimize adverse effects in elderly patients.

Preoperative chemoradiotherapy in older patients with rectal cancer guided by comprehensive geriatric assessment within a multidisciplinary team-a multicenter phase II trial

BACKGROUND

The purpose of this study was to evaluate the safety and efficacy of preoperative concurrent chemoradiotherapy (preCRT) for locally advanced rectal cancer in older people who were classified as "fit" by comprehensive geriatric assessment (CGA).

METHODS

A single-arm, multicenter, phase II trial was designed. Patients were eligible for this study if they were aged 70 years or above and met the standards of "fit" (SIOG1) as evaluated by CGA and of the locally advanced risk category. The primary endpoint was 2-year disease-free survival (DFS). Patients were scheduled to receive preCRT (50 Gy) with raltitrexed (3 mg/m2 on days 1 and 22).

RESULTS

One hundred and nine patients were evaluated by CGA, of whom eighty-six, eleven and twelve were classified into the fit, intermediate and frail category. Sixty-eight fit patients with a median age of 74 years were enrolled. Sixty-four patients (94.1%) finished radiotherapy without dose reduction. Fifty-four (79.3%) patients finished the prescribed raltitrexed therapy as planned. Serious toxicity (grade 3 or above) was observed in twenty-four patients (35.3%), and fourteen patients (20.6%) experienced non-hematological side effects. Within a median follow-up time of 36.0 months (range: 5.9-63.1 months), the 2-year overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) rates were 89.6% (95% CI: 82.3-96.9), 92.4% (95% CI: 85.9-98.9) and 75.6% (95% CI: 65.2-86.0), respectively. Forty-eight patients (70.6%) underwent surgery (R0 resection 95.8%, R1 resection 4.2%), the corresponding R0 resection rate among the patients with positive mesorectal fascia status was 76.6% (36/47).

CONCLUSION

This phase II trial suggests that preCRT is efficient with tolerable toxicities in older rectal cancer patients who were evaluated as fit based on CGA.

TRIAL REGISTRATION

The registration number on ClinicalTrials.gov was NCT02992886 (14/12/2016).

Updates on the Management of Colorectal Cancer in Older Adults

Colorectal cancer (CRC) poses a significant global health challenge. Notably, the risk of CRC escalates with age, with the majority of cases occurring in those over the age of 65. Despite recent progress in tailoring treatments for early and advanced CRC, there is a lack of prospective data to guide the management of older patients, who are frequently underrepresented in clinical trials. This article reviews the contemporary landscape of managing older individuals with CRC, highlighting recent advancements and persisting challenges. The role of comprehensive geriatric assessment is explored. Opportunities for treatment escalation/de-escalation, with consideration of the older adult's fitness level. are reviewed in the neoadjuvant, surgical, adjuvant, and metastatic settings of colon and rectal cancers. Immunotherapy is shown to be an effective treatment option in older adults who have CRC with microsatellite instability. Promising new technologies such as circulating tumor DNA and recent phase III trials adding later-line systemic therapy options are discussed. Clinical recommendations based on the data available are summarized. We conclude that deliberate efforts to include older individuals in future colorectal cancer trials are essential to better guide the management of these patients in this rapidly evolving field.

Trends and Variation in the Use of Radiotherapy in Non-metastatic Rectal Cancer: a 14-year Nationwide Overview from the Netherlands

AIMS

This study describes nationwide primary radiotherapy utilisation trends for non-metastasised rectal cancer in the Netherlands between 2008 and 2021. In 2014, both colorectal cancer screening and a new guideline specifying prognostic risk groups for neoadjuvant treatment were implemented.

MATERIALS AND METHODS

Patients with non-metastasised rectal cancer in 2008-2021 (n = 37 510) were selected from the Netherlands Cancer Registry and classified into prognostic risk groups. Treatment was studied over time and age. Multilevel logistic regression analyses were carried out to identify factors associated with (i) radiotherapy versus chemoradiotherapy use for intermediate rectal cancer and (ii) chemoradiotherapy without versus with surgery for locally advanced rectal cancer.

RESULTS

For early rectal cancer, the use of neoadjuvant radiotherapy decreased (15% to 5% between 2008 and 2021), whereas the use of endoscopic resections increased (8% in 2015, 17% in 2021). In intermediate-risk rectal cancer, neoadjuvant chemoradiotherapy (43% until 2011, 25% in 2015) shifted to radiotherapy (42% in 2008, 50% in 2015), the latter being most often applied in older patients. In locally advanced rectal cancer, the use of chemoradiotherapy without surgery increased (2-4% in 2008-2013, 17% in 2019-2021). Both neoadjuvant treatment in intermediate disease and omission of surgery following chemoradiotherapy in locally advanced disease varied with increasing age (odds ratio>75vs<50: 2.17, 95% confidence interval 1.54-3.06) and treatment region (Southwest and Northwest odds ratio 0.63, 95% confidence interval 0.42-0.93 and odds ratio 0.65, 95% confidence interval 0.44-0.95, respectively, compared with the North).

CONCLUSION

Treatment patterns in non-metastasised rectal cancer significantly changed over time. Effects of both the national screening programme and the new treatment guideline were apparent, as well as a paradigm shift towards organ preservation (watch-and-wait). Observed regional variations may indicate adoption differences regarding new treatment strategies.

Short course radiotherapy versus radiochemotherapy for locally advanced rectal cancers in the elderly (UNICANCER PRODIGE 42/GERICO 12 study): Quality of life and comprehensive geriatric assessment

BACKGROUND

The results of the PRODIGE 42/GERICO 12 study showed that short course radiotherapy had a better tolerance profile than radiochemotherapy, with comparable oncological results. We have included Quality of Life analyses and oncogeriatric evaluations in this study.

PATIENTS AND METHODS

In all, 101 patients ≥75 years of age with resectable T3-T4 rectal adenocarcinoma less than 12 cm from the anal margin received short course radiotherapy (5X5 Gy in one week) or radiochemotherapy (50 Gy, 2 y/f and capecitabine 800 mg/m2, 5 days/week) with delayed surgery (7 weeks ± 1) in both groups. The Quality of Life analyses (EORTC QLQ C-30 et ELD14) were conducted upon inclusion, pre-operatively, at 3, 6 and 12 months post-op, together with the oncogeriatric evaluations, including an evaluation of the IADL and ADL scores, walking speed, GDS15, MMSE, MNA.

RESULTS

We did not highlight any statistical difference for the global EORTC QLQ-C30 score; several factors are statistically in favor of the short course radiotherapy group at 3 months post-op (cognitive functions, fatigue, appetite). In the case of the ELD14 score, the disease burden is perceived as more negative at 3, 6 and 12 months postop in the radiochemotherapy group. The IADL score deteriorated in 44.8 % of the radiochemotherapy group and 14.8 % of the radiotherapy group (p = 0.032); similarly, the GDS15 depression score was better preserved in the short course radiotherapy group (p = 0.05). An analysis of the other scores: ADL, walking speed, MNA, MMSE did not highlight any statistical difference.

CONCLUSION

Short course radiotherapy achieves better results in terms of Quality of Life and preservation of autonomy in patients aged ≥75 treated for locally advanced rectal cancer.

Elderly Rectal Cancer: An Updated Review

PURPOSE OF REVIEW

Treatment of rectal cancer patients of advanced age should be modulated by life expectancy and tolerance. Due to the rapid advance of this field, we aim to conduct an updated review of this topic.

RECENT FINDINGS

The field of elderly rectal cancer has advanced a lot. This review covers all the treatment aspects of elderly rectal cancer, including the prognostic factor, surgery, radiotherapy, chemotherapy, and palliative treatment. We also provide the future aspect of the management of elderly rectal cancer. The advancement of prognostic factor research, surgery, radiotherapy, chemotherapy, and palliative treatment has made the care of elderly rectal cancer patients better. The future of these fields should focus on the definition of the elderly and the application of particle therapy.