Pentoxifylline to treat radiation proctitis: a small and inconclusive randomised trial

Interventions for Managing Late Gastrointestinal Symptoms Following Pelvic Radiotherapy: a Systematic Review and Meta-analysis

AIMS

Pelvic radiotherapy can induce gastrointestinal injury and symptoms, which can affect quality of life. We assessed interventions for managing these symptoms.

MATERIALS AND METHODS

A review of randomised controlled trials published between January 1990 and June 2023 from databases including MEDLINE, EMBASE, CENTRAL, CINAHL, clinicaltrials.gov, ISRCTN and grey literature sources was conducted. Meta-analyses were carried out using the DerSimonian and Laird random effects model to produce overall treatment differences with 95% confidence intervals.

RESULTS

Twenty-eight studies (2392 participants) of varying methodological quality were included. 4% formalin was superior to sucralfate for improving gastrointestinal symptom score (standardised mean difference [SMD] -1.07, 95% confidence interval -1.48 to -0.65). Argon plasma coagulation (APC) was inferior to sucralfate (SMD 1.22, 95% confidence interval 0.84 to 1.59). Counselling positively influenced symptom score (SMD -0.53, 95% confidence interval -0.76 to -0.29), whereas hyperbaric oxygen therapy showed conflicting results. Sucralfate combined with APC increased endoscopic markers of moderate-severe bleeding versus APC alone (risk ratio 2.26, 95% confidence interval 1.12 to 4.55). No definite conclusions on pain, incontinence, diarrhoea, tenesmus or quality of life interventions were confirmed.

CONCLUSIONS

Small study sizes, methodological quality and heterogeneity limit support of any individual intervention. APC and 4% formalin seem to be promising interventions, with further larger randomised controlled trials now warranted.

Comparative efficacy of oral drugs for chronic radiation proctitis - a systematic review

BACKGROUND

Chronic radiation proctitis (CRP) is a long-term complication of pelvic radiotherapy that manifests as rectal bleeding, diarrhoea, fistula formation and obstruction. Treatments such as endoscopic argon plasma coagulation, hyperbaric oxygen therapy and rectal topical formalin have imposed a significant medical burden on CRP patients. In contrast, oral therapies offer a more accessible and acceptable option for managing CRP. Here, we conducted a systematic review of the efficacy of oral treatments for CRP to assess their potential as an effective and convenient treatment option for this condition.

METHODS

We searched the Cochrane Central Register of Controlled Trials, PubMed, Web of Science, China National Knowledge Infrastructure and Chinese VIP in February 2021. We included post-radiotherapy participants with CRP that compared oral medicine alone or in combination with other treatments versus control treatments. The primary outcomes were bleeding, diarrhoea and symptom score. Heterogeneity between studies was checked using Cochrane Q test statistics and I2 test statistics. The Cochrane risk-of-bias tool was used to assess the quality of the included studies.

RESULTS

We included 10 randomised controlled trials (RCTs) and 1 retrospective study with 898 participants. Three placebo-controlled trials evaluated the effects of oral sucralfate on CRP, with meta-analysis showing no significant different with placebo arm. Four trials on TCM demonstrated significant improvement of symptoms, especially for the 3 trials on oral TCM drinks. Retinyl palmitate and high-fibre diet were found to reduce rectal bleeding. The combination of oral pentoxifylline and tocopherol did not significantly change the process of CRP.

CONCLUSIONS

Our study implies that oral TCM drinks, retinyl palmitate and a high-fiber diet showed significant improvement in CRP symptoms, but not with the combination of oral pentoxifylline and tocopherol. Further multicentre, larger-scale RCTs are needed to confirm the efficacy and safety of these treatments and optimize treatment strategies, ultimately improving the quality of life for patients with CRP.

Silk-elastinlike copolymers enhance bioaccumulation of semisynthetic glycosaminoglycan ethers for prevention of radiation induced proctitis

Radiation-induced proctitis (RIP) is a debilitating adverse event that occurs commonly during lower abdominal radiotherapy. The lack of prophylactic treatment strategies leads to diminished patient quality of life, disruption of radiotherapy schedules, and limitation of radiotherapy efficacy due to dose-limiting toxicities. Semisynthetic glycosaminoglycan ethers (SAGE) demonstrate protective effects from RIP. However, low residence time in the rectal tissue limits their utility. We investigated controlled delivery of GM-0111, a SAGE analogue with demonstrated efficacy against RIP, using a series of temperature-responsive polymers to compare how distinct phase change behaviors, mechanical properties and release kinetics influence rectal bioaccumulation. Poly(lactic acid)-co-(glycolic acid)-block-poly(ethylene glycol)-block-poly(lactic acid)-co-(glycolic acid) copolymers underwent macroscopic phase separation, expelling >50% of drug during gelation. Poloxamer compositions released GM-0111 cargo within 1 h, while silk-elastinlike copolymers (SELPs) enabled controlled release over a period of 12 h. Bioaccumulation was evaluated using fluorescence imaging and confocal microscopy. SELP-415K, a SELP analogue with 4 silk units, 15 elastin units, and one elastin unit with lysine residues in the monomer repeats, resulted in the highest rectal bioaccumulation. SELP-415K GM-0111 compositions were then used to provide localized protection from radiation induced tissue damage in a murine model of RIP. Rectal delivery of SAGE using SELP-415K significantly reduced behavioral pain responses, and reduced animal mass loss compared to irradiated controls or treatment with traditional delivery approaches. Histological scoring showed RIP injury was ameliorated for animals treated with GM-0111 delivered by SELP-415K. The enhanced bioaccumulation provided by thermoresponsive SELPs via a liquid to semisolid transition improved rectal delivery of GM-0111 to mice and radioprotection in a RIP model.

Management of Radiation Proctitis

Radiation proctitis is radiation-induced rectal mucositis, occurring as a result of radiation therapy for various pelvic malignancies. The management of radiation proctitis is challenging as guidelines are not currently available, and studies of the various treatment modalities are limited. There are various medical, endoscopic, and surgical measures for treating chronic radiation proctitis. Medical options such as anti-inflammatory agents, antioxidants, formalin application, and hyperbaric oxygen may improve bleeding related to chronic radiation proctitis. Endoscopic measures such as argon plasma coagulation are effective and safe. Surgery is considered for refractory or severe cases. A review and discussion of the different treatment modalities is presented.

Successful Treatment of Acute Radiation Proctitis with Aloe Vera: A Preliminary Randomized Controlled Clinical Trial

BACKGROUND

Acute radiation proctitis (ARP) is a common side-effect that affects up to 50% of patients receiving radiotherapy. The aim of this study was to evaluate the role of a topical preparation of Aloe vera in the treatment of ARP induced by radiotherapy of pelvic area.

SUBJECTS AND INTERVENTIONS

In this double-blind placebo-controlled trial, 20 consecutive patients with ARP after external-beam radiation therapy (46-72 Gy) of pelvic malignancies were randomized to receive either Aloe vera 3% or placebo ointment, 1 g twice daily for 4 weeks. These patients presented with at least two of the following symptoms: rectal bleeding, abdominal/rectal pain, diarrhea, or fecal urgency. These symptoms were rated by the patients in terms of their severity (grade 0-4) for each of the symptoms mentioned earlier at baseline and then weekly for 4 weeks. A symptom index was calculated by the addition of the scores (16 most symptomatic). Radiation Therapy Oncology Group (RTOG) acute toxicity criteria and psychosocial status of the patients were also recorded weekly. The lifestyle impact of the symptoms was assessed by questionnaire grading from 0 (no effect on daily activity) to 4 (afraid to leave home).

RESULTS

There was a significant (p < 0.05) improvement in the symptom index (before treatment vs. after treatment with Aloe vera) for diarrhea (median score: 0.67 vs. 0.11), fecal urgency (median score: 0.89 vs. 0.11), clinical presentation total (median score: 4.33 vs. 1.22), RTOG total (median score: 2.89 vs. 0.89), and lifestyle (median score: 1.1 vs. 0.33). Hemorrhage and abdominal/rectal pain did not improve significantly. The odds ratios for advantage of Aloe vera over placebo for "clinical presentation total" and "RTOG total" were 3.97 (1.3-11.9) and 5.9 (1.6-21.6), respectively.

CONCLUSION

A substantial number of patients with radiation proctitis seem to benefit from therapy with Aloe vera 3% ointment.

Exploring the Management of Radiation Proctitis in Current Clinical Practice

INTRODUCTION

Radiation proctitis is radiation induced rectal mucositis, occurring as a consequence to radiation therapy of the pelvic organs for various pelvic region malignancies. The management of radiation proctitis is extremely challenging as no recommended guidelines are available and limited number of studies are there in the literature involving the various treatment options.

AIM

The aim of the study is the in-depth review of published literature to see the role of various treatment modalities in the management of radiation proctitis.

MATERIALS AND METHODS

An integrative review was undertaken within PubMed, MEDLINE, PMC, GOOGLE SEARCH databases and articles published upto February 2015 were reviewed and analysed. A total of 54 studies were included.

RESULTS

Literature suggests that non surgical therapies are the first line of treatment and surgery is reserved for advanced or refractory cases. Endoscopic therapies form the mainstay of treatment in managing the patients of radiation proctitis. Argon plasma coagulation and laser therapies are preferred. Radiofrequency ablation, cryoablation and mesenchymal stem cell therapy are the upcoming modalities. Medical therapy can be tried alone or in conjunction to endoscopic therapies. In the resistant or refractory cases, surgery can be looked for in the form of diversion or resection with or without anastamosis.

CONCLUSION

Though, a number of options are available, still a lot can be explored in this field to improve the morbidity in the patients and to confirm the superiority of one treatment over other.

Non-surgical interventions for late rectal problems (proctopathy) of radiotherapy in people who have received radiotherapy to the pelvis

BACKGROUND

This is an update of a Cochrane review first published in 2002, and previously updated in 2007. Late radiation rectal problems (proctopathy) include bleeding, pain, faecal urgency, and incontinence and may develop after pelvic radiotherapy treatment for cancer.

OBJECTIVES

To assess the effectiveness and safety of non-surgical interventions for managing late radiation proctopathy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 11, 2015); MEDLINE (Ovid); EMBASE (Ovid); CANCERCD; Science Citation Index; and CINAHL from inception to November 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing non-surgical interventions for the management of late radiation proctopathy in people with cancer who have undergone pelvic radiotherapy for cancer. Primary outcomes considered were: episodes of bowel activity, bleeding, pain, tenesmus, urgency, and sphincter dysfunction.

DATA COLLECTION AND ANALYSIS

Study selection, 'Risk of bias' assessment, and data extraction were performed in duplicate, and any disagreements were resolved by involving a third review author.

MAIN RESULTS

We identified 1221 unique references and 16 studies including 993 participants that met our inclusion criteria. One study found through the last update was moved to the 'Studies awaiting classification' section. We did not pool outcomes for a meta-analysis due to variation in study characteristics and endpoints across included studies.Since radiation proctopathy is a condition with various symptoms or combinations of symptoms, the studies were heterogeneous in their intended effect. Some studies investigated treatments targeted at bleeding only (group 1), some investigated treatments targeted at a combination of anorectal symptoms, but not a single treatment (group 2). The third group focused on the treatment of the collection of symptoms referred to as pelvic radiation disease. In order to enable some comparison of this heterogeneous collection of studies, we describe the effects in these three groups separately.Nine studies assessed treatments for rectal bleeding and were unclear or at high risk of bias. The only treatments that made a significant difference on primary outcomes were argon plasma coagulation (APC) followed by oral sucralfate versus APC with placebo (endoscopic score 6 to 9 in favour of APC with placebo, risk ratio (RR) 2.26, 95% confidence interval (CI) 1.12 to 4.55; 1 study, 122 participants, low- to moderate-quality evidence); formalin dab treatment (4%) versus sucralfate steroid retention enema (symptom score after treatment graded by the Radiation Proctopathy System Assessments Scale (RPSAS) and sigmoidoscopic score in favour of formalin (P = 0.001, effect not quantified, 1 study, 102 participants, very low- to low-quality evidence), and colonic irrigation plus ciprofloxacin and metronidazole versus formalin application (4%) (bleeding (P = 0.007, effect not quantified), urgency (P = 0.0004, effect not quantified), and diarrhoea (P = 0.007, effect not quantified) in favour of colonic irrigation (1 study, 50 participants, low-quality evidence).Three studies, of unclear and high risk of bias, assessed treatments targeted at something very localised but not a single pathology. We identified no significant differences on our primary outcomes. We graded all studies as very low-quality evidence due to unclear risk of bias and very serious imprecision.Four studies, of unclear and high risk of bias, assessed treatments targeted at more than one symptom yet confined to the anorectal region. Studies that demonstrated an effect on symptoms included: gastroenterologist-led algorithm-based treatment versus usual care (detailed self help booklet) (significant difference in favour of gastroenterologist-led algorithm-based treatment on change in Inflammatory Bowel Disease Questionnaire-Bowel (IBDQ-B) score at six months, mean difference (MD) 5.47, 95% CI 1.14 to 9.81) and nurse-led algorithm-based treatment versus usual care (significant difference in favour of the nurse-led algorithm-based treatment on change in IBDQ-B score at six months, MD 4.12, 95% CI 0.04 to 8.19) (1 study, 218 participants, low-quality evidence); hyperbaric oxygen therapy (at 2.0 atmospheres absolute) versus placebo (improvement of Subjective, Objective, Management, Analytic - Late Effects of Normal Tissue (SOMA-LENT) score in favour of hyperbaric oxygen therapy (HBOT), P = 0.0019) (1 study, 150 participants, moderate-quality evidence, retinol palmitate versus placebo (improvement in RPSAS in favour of retinol palmitate, P = 0.01) (1 study, 19 participants, low-quality evidence) and integrated Chinese traditional plus Western medicine versus Western medicine (grade 0 to 1 radio-proctopathy after treatment in favour of integrated Chinese traditional medicine, RR 2.55, 95% CI 1.30 to 5.02) (1 study, 58 participants, low-quality evidence).The level of evidence for the majority of outcomes was downgraded using GRADE to low or very low, mainly due to imprecision and study limitations. 

AUTHORS' CONCLUSIONS

Although some interventions for late radiation proctopathy look promising (including rectal sucralfate, metronidazole added to an anti-inflammatory regimen, and hyperbaric oxygen therapy), single small studies provide limited evidence. Furthermore, outcomes important to people with cancer, including quality of life (QoL) and long-term effects, were not well recorded. The episodic and variable nature of late radiation proctopathy requires large multi-centre placebo-controlled trials (RCTs) to establish whether treatments are effective. Future studies should address the possibility of associated injury to other gastro-intestinal, urinary, or sexual organs, known as pelvic radiation disease. The interventions, as well as the outcome parameters, should be broader and include those important to people with cancer, such as QoL evaluations.

Formalin therapy for hemorrhagic radiation proctitis

BACKGROUND

Radiotherapy within pelvis is a vital component of curative therapy for urological, gynecological and rectal malignances. Rectum is especially vulnerable to secondary radiation injury resulting in proctitis. The most common and life-threatening symptom is rectal hemorrhage. Formalin application into the rectum causes local cauterization of telangiectatic mucosal vessels. The aim of our study was to assess the efficacy of local formalin application in patients with hemorrhagic radiation proctitis.

METHODS

A solution of 4.0% formalin was used in the treatment of 20 patients with clinical and proctoscopic evidence of radiadion proctitis. Treatment involved direct application of 4.0% formalin into the rectum. All patients were followed-up in terms of complete resolution of symptoms or recurrences of bleeding.

RESULTS

A total of 20 patients with a mean age of 69.7 (range, 57-80) years were followed for 51.2 (range, 1-93) months. The mean duration of symptoms was 4.5 (range, 1-10) months and the interval between the end of radiotherapy and symptoms was mostly between 5 and 30 months. Patients required an average of 2 (range, 1-5) formalin treatments. Of the 20 patients, 10 had complete resolution of their symptoms after their first treatment. In 10 patients bleeding recurred and they were offered another formalin instillation and/or 5-ASA suppositories and argon therapy. Complete resolution of symptoms was achieved in all patients.

CONCLUSIONS

Topical formalin instillation is effective, safe, and well-tolerated method for the patients with radiation proctopathy. This therapy may be repeated in case of recurrent bleeding and combined with other methods of treatment.

Management of radiation proctitis

The optimal management of radiation proctitis is ill defined. A variety of alternatives are available and include topical agents (ie, sucralfate enemas, formalin), oral agents (ie, pentoxyfylline, vitamin A), hyperbaric oxygen, and endoscopic interventions (ie, argon plasma coagulation). It is prudent to manage patients conservatively and to intervene only when necessary with the option least likely to exacerbate the proctitis. Rectal biopsies should be avoided as they may precipitate a complication. More aggressive measures, such as argon laser coagulation, should be employed only when more conservative approaches fail.

Treatment of hemorrhagic radiation-induced proctopathy with a 4% formalin application under perianal anesthetic infiltration

AIM: To evaluate the results of hemorrhagic radiation proctopathy treatment with a 4% formalin application.

METHODS: A prospective study was performed. Over a three-year period, 38 patients underwent 4% formalin application under perianal anesthetic infiltration for hemorrhagic radiation proctopathy. All patients included in the study were irradiated for prostate cancer. The patients ranged in age from 56-77 years (average 70 ± 5 years). All of the patients were referred for formalin therapy after noninvasive management had failed. Twenty-four (63.2%) patients underwent a single application, 10 (26.3%) patients underwent 2 applications, and 4 (10.5%) patients underwent 3 applications.

RESULTS: Two to 36 mo (average 12 ± 3 mo) following treatment, 34 patients were interviewed (four were lost to follow-up). Twenty (58.8%) subjects reported complete cure, 8 (23.5%) subjects reported significant improvement, and 6 (17.7%) subjects reported no change. One patient (who underwent a colostomy at a regional hospital with no specialized services available for previous bleeding episodes from radiation proctopathy) was cured, and the colostomy was closed. One patient (2.6%) developed rectal mucosal damage after the second application.

CONCLUSION: A 4-min application of 4% formalin for hemorrhagic radiation-induced proctopathy under perianal anesthetic infiltration in patients who have received external radial radiation therapy for prostate cancer is simple, reasonably safe, inexpensive, generally well tolerated, and effective.

Endoscopic and medical therapy for chronic radiation proctopathy: a systematic review

BACKGROUND

Chronic radiation proctopathy is associated with significant morbidity. The effectiveness of endoscopic and medical therapies has not been evaluated.

OBJECTIVES

The aim of this study was to conduct a systematic review of the effectiveness of endoscopic and comparative medical therapies for chronic radiation proctopathy.

DATA SOURCES

A comprehensive search Medline and PubMed was performed.

STUDY SELECTION

A comprehensive literature search was performed for studies of endoscopic and medical therapy for clinical and endoscopic improvement in chronic radiation proctopathy from January 1990 until December 2010. The quality of the overall evidence was rated according to the Grading of Recommendations, Assessment, Development, and Evaluation Working Group.

SETTING

Patients in both inpatient and outpatient settings were assessed.

PATIENTS

Patients experiencing chronic radiation proctopathy were included.

INTERVENTIONS

Patients had undergone medical or endoscopic treatments for chronic radiation proctopathy.

MAIN OUTCOME MEASUREMENTS

The primary outcomes measured were the resolution or improvement in symptoms.

RESULTS

A total of 39 studies were found, of which 27 evaluated endoscopic therapy and 12 evaluated medical therapy chronic radiation proctopathy. Overall, there is low-level evidence for the effectiveness of endoscopic therapy with argon plasma coagulation in reducing short-term (≤6 weeks) symptoms of chronic radiation proctopathy and insufficient evidence for long-term improvement. There is moderate-level evidence for the use of sucralfate enemas and low-level evidence for use of short-chain fatty acid enemas and hyperbaric oxygen. There is insufficient evidence for other agents: topical formalin, 5-aminosalicylic acid compounds, sulfasalazine, vitamin A, and pentoxifylline.

LIMITATIONS

Individual authors were not contacted, and the search was limited to English language journals only.

CONCLUSION

Endoscopic treatment with argon plasma coagulation appears effective in the short-term outcome of chronic radiation proctopathy. There is a moderate level of evidence for the use of sucralfate enemas. Large, randomized, placebo-controlled studies evaluating endoscopic and medical therapies for chronic radiation proctopathy are needed.

Treatment of chronic radiation proctitis with cryoablation

BACKGROUND

Chronic radiation proctitis (CRP) is a common problem in patients receiving pelvic radiation. Current therapies have the potential for deep tissue injury with ulcerations, perforation, and fistula formation. Cryospray ablation therapy offers superficial ablation of mucosa and is a potential method to endoscopically treat CRP safely and effectively.

OBJECTIVE

To determine tolerability of and response to cryotherapy in patients with radiation proctitis.

DESIGN

Prospective case-series pilot study.

SETTING

Baylor College of Medicine, Michael E. DeBakey Medical Center, Houston, Texas.

PATIENTS

Ten patients were prospectively recruited with chronic hemorrhagic radiation proctitis.

INTERVENTIONS

Endoscopic cryoablation of CRP.

MAIN OUTCOME MEASUREMENTS

Symptom severity of CRP was obtained by using the Radiation Proctitis Severity Assessment Scale (RPSAS). Endoscopic assessment was obtained using the rectal telangiectasia density grade. The primary endpoint of the study was endoscopic improvement of CRP based on the change in rectal telangiectasia density at 3-month follow-up. Secondary endpoints included symptomatic improvement based on RPSAS and adverse events at 3 months.

RESULTS

Ten patients with hemorrhagic radiation proctitis were treated with endoscopic cryoablation. Endoscopic severity improved as measured by rectal telangiectasia density from 2.7 to 1.7 (P=.004). Overall subjective clinical scores improved as determined by the Radiation Proctitis Severity Assessment Scale from 27.7 to 13.6 (P=.003). Endoscopic improvement correlated with symptom improvement.

LIMITATIONS

Nonpowered case series pilot study.

CONCLUSIONS

Cryoablation improved clinical and endoscopic indices in CRP. Further controlled studies are needed to identify the safety and efficacy of cryoablation for CRP.