Evaluation of clinical and endoscopic toxicity after external beam radiotherapy and endorectal brachytherapy in elderly patients with rectal cancer treated in the HERBERT study

Palliative pelvic radiotherapy for symptomatic frail or metastatic patients with rectal adenocarcinoma: A systematic review

BACKGROUND

Locally advanced rectal cancer can cause severe symptomatic pelvic morbidity such as pain, haemorrhage or bowel obstruction for frail or metastatic patients, which are often unfit to undergo surgery or intense systemic treatment. The most frequent radiation schedule is 25 Gy/ 5f but the optimal dose is yet to determine. Our aim was to conduct a systematic review on the efficacy and toxicity of the published radiation schedules of palliative rectal cancer.

METHODS

Systematic literature of the Medline, Embase and Cochrane library databases were performed throughout the year 2023. Published articles on palliative external beam radiation therapy (EBRT) for locally advanced or metastatic rectal cancer reporting on symptom palliation, overall survival (OS) and quality of life (QOL) were eligible for inclusion.

RESULTS

Thirteen studies were included, five of them were prospective studies. There were large variations in radiation schedules, associated chemotherapy and palliative care. Pooled overall symptomatic response rate was 71 %, while response rates were respectively 90 %, 85 %, and 84 % for pain, bleeding, and pelvic symptoms. Acute toxicities were mostly mild genitourinary or gastrointestinal.

CONCLUSIONS

Short course palliative radiation for LARC for frail or metastatic patients is efficient for symptom palliation with few adverse effects. A short course EBRT with an integrated IMRT boost on the tumoral volume could be of interest.

New findings in prognostic factor assessment for adenocarcinoma of transverse colon: a comparison study between competing-risk and COX regression analysis

Purpose

Competing-risk analysis was used to accurately assess prognostic factors for cancer-specific death in patients with adenocarcinoma of transverse colon (ATC), and the results were compared with those from a conventional Cox regression analysis.

Materials and Methods

Patients diagnosed with ATC between 2000 and 2019 were selected from the Surveillance, Epidemiology, and End Results database. The crude mortality rates of patients with ATC were calculated and their differences were tested using the Gray's test, respectively. In performing multivariate analysis, the Cox regression model and the subdistribution hazard function (SD) in competing risk analysis were utilized, respectively.

Results

This study included 21,477 eligible patients. The SD model indicated that age, etc. are actual independent prognostic factors. In contrast to previous recognition, the results of the Cox regression showed false-positives for sex and Carcinoembryonic antigen, and underestimated point-estimates in the stage and American Joint Committee on Cancer stage due to competing events. A detailed comparison of treatment revealed that the larger surgical scopes were prognostic risk factors compared with the smaller scope of local tumor excision, partial colectomy, or segmental resection. Patients treated with external proton beam radiotherapy had an increased risk compared with those with no radiotherapy and internal radiotherapy.

Conclusions

After comparing the results of the two methods and mitigating the significant bias introduced by Cox regression, we found independent factors that really affect the prognosis of ATC. On the other hand, in terms of ATC, a larger surgical scope and external proton beam radiotherapy may not improve the long-term survival of patients. Therefore, when faced with ATC patients, these differences should be noted and treated differently from common colorectal cancer patients. Thus, clinicians are able to give more targeted treatment plans and prognostic assessments.

Non-operative management involving chemoradiation therapy combined with high-dose-rate brachytherapy for T3 rectal cancer using a vaginal shielded cylindrical applicator: a technical report

It has been shown that a group of rectal cancer patients will achieve a pathological complete response following preoperative chemoradiotherapy, and non-operative management has recently gained attention. To escalate the tumour dose and increase the likelihood of pathological complete response, brachytherapy can play an important role in safely increasing the total dose. However, at the time this report was published, an applicator dedicated to rectal brachytherapy was unaffordable in Japan. Here, we report two T3 rectal cancer patients who were inoperable or refused surgery and treated by chemoradiotherapy following intracavitary brachytherapy involving a vaginal cylinder applicator with lead shielding.

New Opportunities for Minimizing Toxicity in Rectal Cancer Management

Advances in multimodal management of locally advanced rectal cancer (LARC), consisting of preoperative chemotherapy and/or radiotherapy followed by surgery with or without adjuvant chemotherapy, have improved local disease control and patient survival but are associated with significant risk for acute and long-term morbidity. Recently published trials, evaluating treatment dose intensification via the addition of preoperative induction or consolidation chemotherapy (total neoadjuvant therapy [TNT]), have demonstrated improved tumor response rates while maintaining acceptable toxicity. In addition, TNT has led to an increased number of patients achieving a clinical complete response and thus eligible to pursue a nonoperative, organ-preserving, watch and wait approach, thereby avoiding toxicities associated with surgery, such as bowel dysfunction and stoma-related complications. Ongoing trials using immune checkpoint inhibitors in patients with mismatch repair-deficient tumors suggest that this subgroup of patients with LARC could potentially be treated with immunotherapy alone, sparing them the toxicity associated with preoperative treatment and surgery. However, the majority of rectal cancers are mismatch repair-proficient and less responsive to immune checkpoint inhibitors and require multimodal management. The synergy noted in preclinical studies between immunotherapy and radiotherapy on immunogenic tumor cell death has led to the design of ongoing clinical trials that explore the benefit of combining radiotherapy, chemotherapy, and immunotherapy (mainly of immune checkpoint inhibitors) and aim to increase the number of patients eligible for organ preservation.

Quality-of-life outcomes in older patients with early-stage rectal cancer receiving organ-preserving treatment with hypofractionated short-course radiotherapy followed by transanal endoscopic microsurgery (TREC): non-randomised registry of patients unsuitable for total mesorectal excision

BACKGROUND

Older patients with early-stage rectal cancer are under-represented in clinical trials and, therefore, little high-quality data are available to guide treatment in this patient population. The TREC trial was a randomised, open-label feasibility study conducted at 21 centres across the UK that compared organ preservation through short-course radiotherapy (SCRT; 25 Gy in five fractions) plus transanal endoscopic microsurgery (TEM) with standard total mesorectal excision in adults with stage T1-2 rectal adenocarcinoma (maximum diameter ≤30 mm) and no lymph node involvement or metastasis. TREC incorporated a non-randomised registry offering organ preservation to patients who were considered unsuitable for total mesorectal excision by the local colorectal cancer multidisciplinary team. Organ preservation was achieved in 56 (92%) of 61 non-randomised registry patients with local recurrence-free survival of 91% (95% CI 84-99) at 3 years. Here, we report acute and long-term patient-reported outcomes from this non-randomised registry group.

METHODS

Patients considered by the local colorectal cancer multidisciplinary team to be at high risk of complications from total mesorectal excision on the basis of frailty, comorbidities, and older age were included in a non-randomised registry to receive organ-preserving treatment. These patients were invited to complete questionnaires on patient-reported outcomes (the European Organisation for Research and Treatment of Cancer Quality of Life [EORTC-QLQ] questionnaire core module [QLQ-C30] and colorectal cancer module [QLQ-CR29], the Colorectal Functional Outcome [COREFO] questionnaire, and EuroQol-5 Dimensions-3 Level [EQ-5D-3L]) at baseline and at months 3, 6, 12, 24, and 36 postoperatively. To aid interpretation, data from patients in the non-randomised registry were compared with data from those patients in the TREC trial who had been randomly assigned to organ-preserving therapy, and an additional reference cohort of aged-matched controls from the UK general population. This study is registered with the ISRCTN registry, ISRCTN14422743, and is closed.

FINDINGS

Between July 21, 2011, and July 15, 2015, 88 patients were enrolled onto the TREC study to undergo organ preservation, of whom 27 (31%) were randomly allocated to organ-preserving therapy and 61 (69%) were added to the non-randomised registry for organ-preserving therapy. Non-randomised patients were older than randomised patients (median age 74 years [IQR 67-80] vs 65 years [61-71]). Organ-preserving treatment was well tolerated among patients in the non-randomised registry, with mild worsening of fatigue; quality of life; physical, social, and role functioning; and bowel function 3 months postoperatively compared with baseline values. By 6-12 months, most scores had returned to baseline values, and were indistinguishable from data from the reference cohort. Only mild symptoms of faecal incontinence and urgency, equivalent to less than one episode per week, persisted at 36 months among patients in both groups.

INTERPRETATION

The SCRT and TEM organ-preservation approach was well tolerated in older and frailer patients, showed good rates of organ preservation, and was associated with low rates of acute and long-term toxicity, with minimal effects on quality of life and functional status. Our findings support the adoption of this approach for patients considered to be at high risk from radical surgery.

FUNDING

Cancer Research UK.

Features on Endoscopy and MRI after Treatment with Contact X-ray Brachytherapy for Rectal Cancer: Explorative Results

After neoadjuvant (chemo)radiotherapy for rectal cancer, contact X-ray brachytherapy (CXB) can be applied aiming at organ preservation. This explorative study describes the early features on endoscopy and MRI after CXB. Patients treated with CXB following (chemo)radiotherapy and a follow-up of ≥12 months were selected. Endoscopy and MRI were performed every 3 months. Expert readers scored all the images according to structured reporting templates. Thirty-six patients were included, 15 of whom obtained a cCR. On endoscopy, the most frequently observed feature early in follow-up was an ulcer, regardless of whether patients developed a cCR. A flat, white scar and tumor mass were common at 6 months. Focal tumor signal on T2W-MRI and mass-like high signal on DWI were generally absent in patients with a cCR. An ulceration on T2W-MRI and "reactive" mucosal signal on DWI were observed early in follow-up regardless of the final tumor response. The distinction between a cCR and a residual tumor generally can be made at 6 months. Features associated with a residual tumor are tumor mass on endoscopy, focal tumor signal on T2W-MRI, and mass-like high signal on DWI. Early recognition of these features is necessary to identify patients who will not develop a cCR as early as possible.

Image-Guided Brachytherapy for Rectal Cancer: Reviewing the Past Two Decades of Clinical Investigation

(1) Background: The introduction of total mesorectal excision (TME) for rectal cancer has led to improvement in local recurrence (LR) outcomes. Furthermore, the addition of preoperative external beam radiotherapy to TME reduces LR to less than 6%. As a trade-off to these gradual improvements in local therapies, the oncology community’s work is now focusing on mitigating treatment-related toxicities. In other words, if a small proportion of 4–6% of rectal cancer patients benefit from additional local therapy beyond TME, the burden of acute and long-term side effects must be considered with care. (2) Methods: With the introduction of better-quality imaging for tumor visualization and treatment planning, a new conformed radiation treatment was introduced with high-dose-rate endorectal brachytherapy. The treatment concept was tested in phase I and II studies: first in the pre-operative setting, and then as a boost after external beam radiation therapy, as a dose-escalation study, to achieve higher local tumor control. (3) Results: HDREBT is safe and effective in achieving a high tumor regression rate and was well tolerated in a phase II multicenter and two matched-pair studies. (4) Conclusions: HDREBT is a conformed radiation therapy that is safe and effective, and is presently explored in a phase III dose-escalation study in the NOM of patients with operable rectal cancer.

Clinical applications of high dose rate endorectal brachytherapy for patients with rectal cancer

With the establishment of total mesorectal excision for the treatment of rectal cancer, local recurrence rates have significantly decreased. The addition of preoperative external beam irradiation further reduces this risk to less than 6%. As the local treatment becomes successful and more widely used, the associated treatment-related toxicity is becoming clinically important. If 4 to 6% of the patients are to benefit from neo-adjuvant therapy before total mesorectal excision, the acute and the long-term toxicity burden must be reasonable. With the introduction of better-quality imaging for tumour visualization and treatment planning, a new-targeted radiation treatment was introduced with high dose rate endorectal brachytherapy. The treatment concept was tested in phase I and II studies first in the preoperative setting, then as a boost after external beam radiation therapy as a dose escalation study to achieve higher tumour local control in a radical treatment setting with no surgery. High dose rate endorectal brachytherapy is safe and effective in achieving high tumour regression rate and was well tolerated. It is presently explored in a phase III dose escalation study in the non-operative management of patients with operable rectal cancer.

Image-guided high-dose-rate brachytherapy for rectal cancer: technical note and first clinical experience on an organ-preserving approach

PURPOSE

As the population ages, the incidence of rectal cancer among elderly patients is rising. Due to the risk of perioperative morbidity and mortality, alternative nonoperative treatment options have been explored in elderly and frail patients who are clinically inoperable or refuse surgery.

METHODS

Here we present technical considerations and first clinical experience after treating a cohort of six rectal cancer patients (T1‑3, N0‑1, M0; UICC stage I-IIIB) with definitive external-beam radiation therapy (EBRT) followed by image-guided, endorectal high-dose-rate brachytherapy (HDR-BT). Patients were treated with 10-13 × 3 Gy EBRT followed by HDR-BT delivering 12-18 Gy in two or three fractions. Tumor response was evaluated using endoscopy and magnetic resonance imaging of the pelvis.

RESULTS

Median age was 84 years. All patients completed EBRT and HDR-BT without any high-grade toxicity (> grade 2). One patient experienced rectal bleeding (grade 2) after 10 weeks. Four patients (67%) demonstrated clinical complete response (cCR) or near cCR, there was one partial response, and one residual tumor and hepatic metastasis 8 weeks after HDR-BT. The median follow-up time for all six patients is 42 weeks (range 8-60 weeks). Sustained cCR without evidence of local regrowth has been achieved in all four patients with initial (n)cCR to date.

CONCLUSION

Primary EBRT combined with HDR-BT is feasible and well tolerated with promising response rates in elderly and frail rectal cancer patients. The concept could be an integral part of a highly individualized and selective nonoperative treatment offered to patients who are not suitable for or refuse surgery.

Contact X-ray Brachytherapy for Older or Inoperable Rectal Cancer Patients: Short-Term Oncological and Functional Follow-Up

Total mesorectal excision for rectal cancer is a major operation associated with morbidity and mortality. For older or inoperable patients, alternatives are necessary. This prospective study evaluated the oncological and functional outcome and quality of life of older or inoperable rectal cancer patients treated with a contact X-ray brachytherapy boost to avoid major surgery. During follow-up, tumor response and toxicity on endoscopy were scored. Functional outcome and quality of life were assessed with self-administered questionnaires. Additionally, in-depth interviews regarding patients' experiences were conducted. Nineteen patients were included with a median age of 80 years (range 72-91); nine patients achieved a clinical complete response and in another four local control of the tumor was established. The 12 month organ-preservation rate, progression-free survival, and overall survival were 88%, 78%, and 100%, respectively. A transient decrease in quality of life and bowel function was observed at 3 months, which was generally restored at 6 months. In-depth interviews revealed that patients' experience was positive despite the side-effects shortly after treatment. In older or inoperable rectal cancer patients, contact X-ray brachytherapy can be considered an option to avoid total mesorectal excision. Contact X-ray brachytherapy is well-tolerated and can provide good tumor control.

Impact of dose-escalated chemoradiation on quality of life in patients with locally advanced rectal cancer: two year follow-up of the randomized RECTAL-BOOST trial

BACKGROUND

Dose-escalated chemoradiation (CRT) for locally advanced rectal cancer (LARC) did not result in higher complete response rates, but initiated more tumor regression in the randomized XXXXX trial (Clinicaltrials.gov XXXXX). This study compared patient reported outcomes (PROs) between patients who received dose-escalated CRT (5 × 3Gy boost + CRT) or standard CRT for two years following randomization.

METHODS

Patients with LARC, participating in the XXXXX trial, filled out EORTC QLQ-C30 and CR29 questionnaires on quality of life (QoL) and symptoms at baseline, 3, 6, 12, 18 and 24 months following start of treatment. Between-group differences in functional QoL domains were estimated using a linear mixed-effects model and expressed as effect size (ES). Symptom scores were compared using Mann-Whitney U test.

RESULTS

Patients treated with dose-escalated CRT (boost group, n=51) experienced a significantly stronger decline in global health at 3 and 6 months (ES -0,4 and ES -0,4), physical functioning at 6 months (ES -1,1), role functioning at 3 and 6 months (ES -0,8 and ES -0,6) and social functioning at 6 months (ES -0,6) compared to patients treated with standard CRT (control group, n=64). The boost group reported significantly more fatigue at 3 and 6 months (83% vs. 66% resp. 89% vs. 76%), pain at 3 and 6 months (67% vs. 36% resp. 80% vs. 44%) and diarrhea at 3 months (45% vs. 29%) compared to the control group. From 12 months onwards, QoL and symptoms were similar between groups, apart from more blood/mucus in stool in the boost group.

CONCLUSION

In patients with LARC, dose-escalated CRT resulted in a transient deterioration in global health, physical, role, and social functioning and more pain, fatigue and diarrhea at 3 and 6 months following start of treatment compared to standard CRT. From 12 months onwards, the impact of dose-escalated CRT on QoL largely resolved.

The clinical features, management, and survival of elderly patients with colorectal cancer

Background

As the population ages, the number of elderly patients with colorectal cancer is increasing year by year. However, older people have rarely been the focus of studies on colorectal cancer. Therefore, in the present study, we aimed to carry out a retrospective analysis of this patient subgroup.

Methods

A retrospective study of clinical data of patients aged over 80 years who died from colorectal cancer in our hospital between 1993 and 2020 was performed. Logistic regression, the Kaplan-Meier method, and a multivariate Cox proportional hazards model were used to analyze the overall survival and treatment outcomes of the patients.

Results

A total of 87 patients were included in the study. The overall median survival was 45 months. In most patients, the primary lesion was located in the right colon. One-quarter of the patients refused to accept any treatment. Patients with stage IV tumors, who accounted for the largest proportion of the study population, displayed a higher rate of abandoning treatment than did patients of other stages. Almost all patients with stages II and III accepted surgery. Patients who underwent surgery to treat their colorectal cancer had longer survival than those who did not.

Conclusions

Old age should not be a reason for giving up treatment for colorectal cancer. The treatment of colorectal cancer patients aged 80 years and above requires individualized evaluation and more aggressive treatment to achieve greater benefits.

Unintended consequences of treating early rectal cancers for complete clinical response with chemoradiotherapy

The aim was to examine the current trend in rectal cancer, which is to extend ’watch-and-wait’ to earlier-stage tumors, not normally treated with chemoradiotherapy, to define the up-side and down-side regarding quality of life (QOL) and anorectal/sexual/urinary function from this approach. We reviewed the literature regarding a ‘watch-and-wait’ strategy after neoadjuvant chemoradiotherapy. The primary outcome measure was complete clinical response. Secondary measures included colostomy rate, functional outcomes and QOL. There is a trend to use chemoradiotherapy in earlier tumors using dose-escalation of radiation and/or additional chemotherapy, resulting in high rates of complete clinical response, which may impact adversely on QOL if radical surgery is subsequently required. Focusing on organ-preservation as the primary goal of treatment rather than overall functional outcomes and QOL for the whole population, may not provide patients with sufficient information for optimal decision-making.

Dose-volume analysis of predictors for acute anal toxicity after radiotherapy in prostate cancer patients

Background

This study aimed to evaluate the clinical and dosimetric factors predictive of acute anal toxicity (AAT) after radiotherapy in prostate cancer (PCa) patients with or without hemorrhoids.

Methods

We analyzed data from 347 PCa patients (248 cases treated from July 2013 to November 2017 for training cohort and 99 cases treated in 2018 for validation cohort) treated with pelvic radiotherapy at a single institution. Anal canal dose–volume histogram was used to determine the prescribed dose. Univariate and multivariate analyses were used to evaluate the risk of AAT as a function of clinical and dosimetric factors.

Results

Totally, 39.5% (98/248) and 31.3% (31/99) of the PCa patients developed AAT in training and validation cohorts, respectively. The incidence of AAT was much higher in patients with hemorrhoids than in those without hemorrhoids in both training and validation cohorts. Hemorrhoids and volume received more than 20 Gy (V20) were valuated as independent factors for predicting AAT in training cohort. Similar results were also observed in our validation cohort. The combination of hemorrhoids and high anal canal V20 (> 74.93% as determined by ROC curves) showed the highest specificity and positive predictive values for predicting AAT in both training and validation cohorts.

Conclusions

AAT occurs commonly in PCa patients with hemorrhoids during and after pelvic radiotherapy. Hemorrhoids and anal canal V20 are independent predictors of AAT. These factors should be carefully considered during treatment planning to minimize the incidence of AAT.

Modern Brachytherapy

Brachytherapy involves the placement of radioactive sources within or very close to the tumor. This placement allows a high dose of radiotherapy to be delivered to the tumor while sparing the surrounding normal tissue. The delivery of brachytherapy has changed markedly over the years, with newer radioactive sources making delivery safer, image guidance techniques allowing more accurate placement of sources, and advanced planning systems allowing brachytherapy to be truly adaptive. This article explores the most modern techniques and current uses of brachytherapy in the treatment of gynecological, prostate, breast, rectal, and skin cancers.

Image Guided Adaptive Endorectal Brachytherapy in the Nonoperative Management of Patients With Rectal Cancer

PURPOSE

Organ preservation or nonoperative management of rectal cancer is of growing interest. Image guided adaptive endorectal brachytherapy is a radiation dose escalation modality: we explored its role in elderly patients unfit for surgery and patients refusing surgery.

METHODS AND MATERIALS

In this registry study, patients with rectal cancer who were ineligible for surgery received 40 Gy in 16 fractions of pelvic external beam radiation therapy. They subsequently received 3 weekly image guided adaptive brachytherapy boosts of 10 Gy to the residual tumor, for a total of 30 Gy in 3 fractions. Complete clinical response (cCR) and local control were the primary endpoints.

RESULTS

94 patients were included; the median age was 81.1 years. With a median follow-up of 1.9 years, the proportion of cCR was 86.2%, the tumor regrowth proportion was 13.6%, and the cumulative incidence of local relapse was 2.7% at 1 year and 16.8% at 2 years. When considering responders and nonresponders, the 2-year local control was 71.5%. The overall survival at 2 years was 63.6%. Acute rectal grade 1 to 2 toxicity included all patients: 12.8% of patients had late bleeding requiring iron replacement, blood transfusions, or argon plasma therapy.

CONCLUSIONS

Results of this registry study, evaluating radiation dose escalation for elderly medically unfit patients with unselected tumors, reveal that a high proportion of patients achieved cCR with a manageable toxicity profile. This technology will likely contribute to the challenging nonoperative management paradigm of rectal cancer.

Predictive factors for response and toxicity after brachytherapy for rectal cancer; results from the HERBERT study

PURPOSE

The HERBERT study was a dose-finding feasibility study of a high-dose rate endorectal brachytherapy (HDREBT) boost after external beam radiotherapy (EBRT) in elderly patients with rectal cancer who were unfit for surgery. This analysis evaluates the association of patient, tumor and dosimetric parameters with tumor response and toxicity after HDREBT in definitive radiotherapy for rectal cancer.

PATIENTS AND METHODS

The HERBERT study included 38 inoperable patients with T2-3N0-1 rectal cancer. Thirteen fractions of 3 Gy EBRT were followed by three weekly HDREBT applications of 5-8 Gy per fraction. Clinical and dosimetric parameters were tested for correlation with clinical complete response (cCR), sustained partial/complete response (SR), patient reported bowel symptoms, physician reported acute and late proctitis (CTCAE v3) and endoscopically scored toxicity.

RESULTS

Thirty-five patients completed treatment and were included in the current analyses. Twenty of 33 evaluable patients achieved a cCR, the median duration of a sustained response was 32 months. Tumor volume at diagnosis showed a strong association with clinical complete response (OR 1.15; p = 0.005). No dose-response correlation was observed in this cohort. Prescribed dose to the brachytherapy CTV (D90) correlated with acute and late physician reported proctitis while CTV volume, CTV width and high dose regions in the CTV (D1cc/D2cc) were associated with endoscopic toxicity at the tumor site.

CONCLUSION

Tumor volume is the most important predictive factor for tumor response and a higher dose to the brachytherapy CTV increases the risk of severe clinically and endoscopically observed proctitis after definitive radiotherapy in elderly patients with rectal cancer.

Optimal management of localized rectal cancer in older patients

In advising the optimal management for older patients, health care professionals try to balance the risks from frailty, vulnerability, and comorbidity against the patient's ultimate prognosis, potential functional outcomes and quality of life (QOL). At the same time it is important to involve the patient and incorporate their preferences. But how can we present and balance the potential downside of radical radiotherapy and risks of unsalvageable recurrence against the potential risks of postoperative morbidity and mortality associated with radical surgery? There are currently no nationally approved and evidence-based guidelines available to ensure consistency in discussions with older adults or frail and vulnerable patients. In this overview we hope to provide an insightful discussion of the relevant issues and options currently available.