Gut Microbiota-Derived 3-Hydroxybutyrate Blocks GPR43-Mediated IL6 Signaling to Ameliorate Radiation Proctopathy.

Radiation proctopathy (RP) is a common complication of radiotherapy for pelvic malignancies with high incidence. RP accompanies by microbial dysbiosis. However, how the gut microbiota affects the disease remains unclear. Here, metabolomics reveals that the fecal and serous concentrations of microbiota-derived 3-hydroxybutyrate (3HB) are significantly reduced in RP mice and radiotherapeutic patients. Moreover, the concentration of 3HB is negatively associated with the expression of proinflammatory IL6 that is increased along with the severity of radiation damage. 3HB treatment significantly downregulates IL6 expression and alleviates IL6-mediated radiation damage. Irradiated cell-fecal microbiota co-culture experiments and in vivo assays show that such a radioprotection of 3HB is mediated by GPR43. Microbiome analysis reveals that radiation leads to a distinct bacterial community compared to untreated controls, in which Akkermansia muciniphila is significantly reduced in RP mice and radiotherapeutic patients and is associated with lower 3HB concentration. Gavage of A. muciniphila significantly increases 3HB concentration, downregulates GPR43 and IL6 expression, and ameliorates radiation damage. Collectively, these results demonstrate that the gut microbiota, including A. muciniphila, induce higher concentrations of 3HB to block GPR43-mediated IL6 signaling, thereby conferring radioprotection. The findings reveal a novel implication of the gut-immune axis in radiation pathophysiology, with potential therapeutic applications.

Intrarectal formalin treatment for haemorrhagic radiation-induced proctopathy: efficacy and safety.

AIM: Pelvic radiotherapy is limited by dose-dependent toxicity to surrounding organs. The aim of this prospective study was to evaluate the efficacy and safety of intrarectal formalin treatment for radiotherapy-induced haemorrhagic proctopathy (RHP) at the Royal Marsden Hospital. METHOD: Adult patients were enrolled. Haemoglobin was evaluated before and after formalin treatment. Antiplatelet and/or anticoagulation treatment and administration of transfusion were recorded. The interval between completion of radiotherapy and the first intrarectal 5% formalin treatment was assessed and the dose of radiotherapy was evaluated. Clinical assessment of the frequency and amount of rectal bleeding (rectal bleeding score 1-6) and endoscopic appearance (grade 0-3) were classified. Complications were recorded. RESULTS: Nineteen patients were enrolled, comprising 13 men (68%) and 6 women. The mean age was 75 ± 9 years. The median time between completion of radiotherapy and the first treatment was 20 months [interquartile range (IQR) 15 months] and the median dose of radiotherapy was 68 Gy (IQR 14 Gy). Thirty-two procedures were performed (average 1.7 per patient). In total, 9/19 (47%) patients were receiving anticoagulation and/or antiplatelet medication and 5/19 (26%) received transfusion prior to treatment. The mean value of serum haemoglobin before the first treatment was 110 ± 18 g/L and afterwards it was 123 ± 16 g/L (p = 0.022). The median rectal bleeding score before the first treatment was 6 (IQR 0) and afterwards 2 (IQR 1-4; p < 0.001), while the median endoscopy score on the day of first treatment was 3 (IQR 0) compared with 1 (IQR 1-2) on the day of the last treatment 1 (p < 0.001). One female patient with a persistent rectal ulcer that eventually healed (18 months of healing) subsequently developed rectovaginal fistula (complication rate 1/19, 5%). CONCLUSIONS: Treatment with intrarectal formalin in RHP is effective and safe.

Risk factors associated to argon plasma coagulation treatment failure in patients with chronic radiation proctopathy

Background: argon plasma coagulation (APC) is the current endoscopic treatment of choice for patients who develop chronic radiation proctopathy. The aim of this study was to identify risk factors associated with treatment failure. Methods: one hundred and ninety-nine patients treated with argon plasma coagulation in a single center were retrospectively analyzed. Results: twenty-four (12.06 %) patients were classified as APC treatment failures. Requirement of red blood cells transfusion and/or hemoglobin < 7 g/dl (OR 12.19, 95 % CI: 2.78-53.45, p < 0.001) and severe bleeding frequency (OR 2.76, 95 % CI: 1.13-6.72, p = 0.03) at diagnosis and prior to endoscopic therapy were associated with argon plasma coagulation treatment failure. Nineteen patients of the successful therapy group developed bleeding recurrence; no risk factors were associated with a shorter recurrence-free time. More than four APC sessions were associated to a higher risk of surgical intervention for bleeding control (OR 87.00, 95 % CI: 10.23-740.18, p < 0.001). Conclusion: requirement of red blood cells transfusion and/or hemoglobin < 7 g/dl and a severe bleeding frequency (more than five days per week) were identified as the most important risk factors for treatment failure in patients with chronic radiation proctopathy. (AU)

Laparoscopic Proximally Extended Colorectal Resection With Two-Stage Turnbull-Cutait Pull-Through Coloanal Anastomosis for Late Complications of Chronic Radiation Proctopathy.

Background: Chronic radiation proctopathy (CRP) is a common complication after radiation therapy for pelvic malignancies. Compared with diversion surgery, resection surgery removes the damaged tissue completely to avoid the risks of recurrence and improve patients' outcome. Hence, resection surgery could be an optimal surgical approach when CRP is complicated by late complications. This study aimed to describe a modified surgical procedure of resection surgery and report its preliminary efficacy and safety in treating patients with CRP with late complications. Methods: We retrospectively reviewed the patients who were diagnosed with CRP with late complications and underwent the modified surgical procedure of laparoscopic proximally extended colorectal resection with two-Stage Turnbull-Cutait pull-through coloanal anastomosis (PE-Bacon) between November 2019 and October 2020 in the Sixth Affiliated Hospital of Sun Yat-sen University. Results: A total of 15 patients were performed the modified laparoscopic procedure of PE-Bacon, of which 1 patient underwent conversion from laparoscopic to open operation for intraoperative massive hemorrhage. Overall, the major (Clavien-Dindo III-V) postoperative complications occurred in 1 patient, anastomotic leakage was observed in 2 (13.3%) patients, and anastomotic stricture was observed in 4 (26.7%) patients. No patient had to be reoperated and died. Up to now, at the average follow-up of (524.40 ± 108.39) days, the preoperative symptoms of 93.3% (14/15) patients were relieved, with nine patients achieved complete remission, five patients only suffered minor symptoms. Because of the progression of radiation uropathy, one patient still had a vesicovaginal fistula as pre-operative complication. Colostomy reversal has been performed on 8 (53.3%) patients at an average postoperative duration of 299.5 ± 92.68 days, among whom only 2 patients suffered from major Low Anterior Resection Syndrome (LARS) until now. Conclusions: Laparoscopic PE-Bacon surgery is a safe and feasible surgical procedure for late complications of CRP with low morbidity and high symptom remission rate.

Therapeutics in radiation-induced proctopathy: a systematic review

Malignant neoplasms are increasingly prevalent in the daily clinical practice. Up to 61% of patients with pelvic malignancies undergo pelvic radiotherapy in different doses, which may cause intestinal damage, and the rectum is the segment most frequently affected due to its fixed position in the pelvis. Currently, there are several strategies to minimize the effects of radiation on the tissues surrounding the neoplastic site; despite those strategies, radiotherapy can still result in serious damage to organs and structures, and these injuries accompany patients throughout their lives. One of the most common damages resulting from pelvic radiotherapy is acute proctitis.The diagnosis is confirmed by visualizing the rectal mucosa through rigid or flexible rectosigmoidoscopy and colonoscopy. The objective of the present study was to review the forms of radiation-induced proctopathytherapy, and to evaluate the results of each method to propose a standardization for the treatment of this pathology. Despite the prevalence of radiation-induced proctopathy, there is no definitive standardized treatment strategy so far. The first approach can be tried with local agents, such as mesalazine and formalin. For refractory cases, control can usually be achieved with argon plasma coagulation, hyperbaric oxygen, and radiofrequency ablation therapies. Regarding the study of radiation-induced proctopathy, there is a lack of robust studies with large samples and standardized therapies to be compared. There is a lack of double-blinded, randomized controlled studies to determine a definitive standard treatment algorithm. (AU)

Hyperbaric oxygen therapy as a complementary treatment for radiation proctitis: Useless or useful? - A literature review.

Radiotherapy (RT) is the backbone of multimodality treatment of more than half of cancer cases. Despite new modern RT techniques, late complications may occur such as radiation proctitis (RP). The natural history of RP is unpredictable. Minor symptoms may resolve spontaneously or require conservative treatment. On the other hand, for similar and uncomplicated clinical contexts, symptoms may persist and can even be refractory to the progressive increase in treatment measures. Over the last decades, an enormous therapeutic armamentarium has been considered in RP, including hyperbaric oxygen therapy (HBOT). Currently, the evidence regarding the impact of HBOT on RP and its benefits is conflicting. Additional prospective and randomised studies are necessary to validate HBOT's effectiveness in the 'real world' clinical practice. This article reviewed the relevant literature on pathophysiology, clinical presentation, different classifications and discuss RP management including a proposal for a therapeutic algorithm with a focus on HBOT.

[Feasibility and safety of laparoscopic Parks procedure for chronic radiation proctopathy].

Objective: To preliminarily evaluate the feasibility and safety of laparoscopic Parks procedure for chronic radiation proctopathy (CRP). Methods: A descriptive cohort study was carried out. The clinical and follow-up data of 19 patients who received laparoscopic Parks procedure due to CRP in the Sixth Affiliated Hospital of Sun Yat-sen University from July 2013 to March 2019 were retrospectively analyzed. Inclusion criteria: (1) serious late complications occurred after pelvic radiotherapy, e.g.serious intractable hematochezia (hemoglobin <70 g/L), intractable anal pain (numerical rating scale >7), rectostenosis, perforation, and fistula. (2) imaging examinations including colonoscopy, pelvic MRI and/or chest, abdomen and pelvic CT were performed before surgery to confirm the lesions. Exclusion criteria: (1) preoperative or intraoperative diagnosis of tumor recurrence; (2) only ostomy was performed after laparoscopic exploration; (3) after neoadjuvant radiotherapy for rectal cancer; (4) incomplete medical records. Surgical procedures: (1) Laparoscopic exploration: tumor recurrence was excluded, and the range of radioactive damage in the intestine was determined. Marks were made on the proximal sigmoid colon without grossly obvious edema, thickening or radioactive injuries. (2) Abdominal operation: the right mesentery of sigmoid colon and rectum was opened, inferior mesenteric vein and inferior mesenteric artery were divided and the Toldt gap was expanded inwards and cephalad. The outside of left hemicolon was freed, the gastrocolic ligament was opened, the splenic flexure was fully mobilized, and the rectum was separated from the rear, side and front to the lowest point. Then perineal operation was performed. (3) Perineal operation: the whole layer of rectum wall was cut thoroughly at 1cm below the lesion's lower margin, the space around the rectum was fully separated, the rectum and sigmoid colon was pulled out through the anus and cut off at the site of the grossly normal intestine, the diseased bowel was removed and a coloanal anastomosis was made. (4) A protective stoma was performed. Conditions of operation, complication and symptom relief were summarized. A descriptive statistic method was used to analyze the results. Results: All the 19 patients were female with a median age of 53 (interquartiles, 50, 56) years old, of whom 18 patients had primary cervical cancer. Surgical indications: 9 cases were rectovaginal fistula; 9 cases were intractable anal pain, among whom 7 were complicated with deep rectal ulcer; and 1 case was intractable hematochezia with deep rectal ulcer. Eighteen cases completed laparoscopic Parks procedure, while 1 case was converted to laparotomy. The median operative time was 215 (131, 270) minutes, the median bleeding volume was 50 (50, 100) ml, and the median hospital stay was 12 (11, 20) days. There was no perioperative death. Ten cases had postoperative complications, including 3 cases of serious complications (CD grade IIIb and above) within 30 days after operation, of whom one case developed pelvic infection caused by rectovaginal, rectovesical and rectourethral fistula and acute renal failure (IVa); 2 cases developed orifice prolapse and parastomal hernia (IIIb). Seven cases had anastomosis-related complications, including 4 cases of grade A anastomotic leakage and 3 cases of anastomotic stenosis. Symptoms of CRP in the whole group were significantly relieved or disappeared after one year of the operation. Five cases achieved stoma closure. Conclusions: Laparoscopic Parks procedure for chronic radiation proctopathy is safe and feasible, and can effectively improve symptoms. However, the incidence of anastomotic complications is high, so the surgical indications should be strictly controlled.

Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study.

BACKGROUND: Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of life. Radiofrequency ablation (RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease management. AIM: To study feasibility of optical coherence tomography angiography (OCTA) for investigating subsurface vascular alterations in CRP and response to RFA treatment. METHODS: Two patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahigh-speed optical coherence tomography (OCT) system over 15 OCT/colonoscopy visits (2 normal patients, 5 RFA-naïve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, without requiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic scoring. RESULTS: OCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 µm in diameter versus abnormal heterogenous enlarged arterioles and venules > 200 µm in diameter were visualized in the rectal submucosa. Abnormal mucosal vasculature occurred in 0 of 2 normal patients and 3 of 5 RFA-naïve patients, while abnormal submucosal vasculature occurred more often, in 1 of 2 normal patients and 5 of 5 RFA-naïve patients. After RFA treatment, vascular abnormalities decreased, with abnormal mucosal vasculature observed in 0 of 8 RFA-follow-up visits and abnormal submucosal vasculature observed in only and 2 of 8 RFA-follow-up visits. CONCLUSION: OCTA visualizes depth-resolved microvascular abnormalities in CRP, allowing assessment of superficial features which are endoscopically visible as well as deeper vasculature which cannot be seen endoscopically. OCTA/OCT of the rectum can be performed in conjunction with, or independently from endoscopy. Further studies are warranted to investigate if OCTA/OCT can elucidate pathophysiology of CRP or improve management.

Efficacy and complications of argon plasma coagulation for hemorrhagic chronic radiation proctitis.

BACKGROUND: Chronic radiation proctitis (CRP) is a complication which occurs in 1%-5% of patients who undergo radiotherapy for pelvic malignancies. Although a wide range of therapeutic modalities are available, there is no literature to date showing any particularly appropriate therapeutic modality for each disease stage. Argon plasma coagulation (APC) is currently recommended as the first-choice treatment for hemorrhagic CRP, however, its indication based on long-term follow-up is still unclear. On the hypothesis that the long-term efficacy and safety of APC are not fully understood, we reviewed APC treatment for patients with hemorrhagic CRP from a single center. AIM: To assess the long-term efficacy and safety of APC for hemorrhagic CRP. METHODS: This is a retrospective study of consecutive patients treated with APC for hemorrhagic CRP from January 2013 to October 2017. Demographics, clinical variables, and typical endoscopic features were recorded independently. Success was defined as either cessation of bleeding or only occasional traces of bloody stools with no further treatments for at least 12 mo after the last APC treatment. We performed univariate and multivariate analyses to identify factors associated with success and risk factors for fistulas. RESULTS: Forty-five patients with a median follow-up period of 24 mo (range: 12-67 mo) were enrolled. Fifteen (33.3%) patients required blood transfusion before APC. Successful treatment with APC was achieved in 31 (68.9%) patients. The mean number of APC sessions was 1.3 (1-3). Multivariate analysis showed that APC failure was independently associated with telangiectasias present on more than 50% of the surface area [odds ratio (OR) = 6.53, 95% confidence interval (CI): 1.09-39.19, P = 0.04] and ulcerated area greater than 1 cm2 (OR = 8.15, 95%CI: 1.63-40.88, P = 0.01). Six (13.3%) patients had severe complications involving rectal fistulation. The only factor significantly associated with severe complications was ulcerated area greater than 1 cm2 (P = 0.035). CONCLUSION: The long-term efficacy of APC for hemorrhagic CRP is uncertain in patients with telangiectasias present on > 50% of the surface area and ulceration > 1 cm2.

Prevention of Recurrent Lower Gastrointestinal Hemorrhage.

This article summarizes current knowledge regarding the incidence of and risk factors associated with recurrent lower gastrointestinal hemorrhage. The literature regarding medical, endoscopic, and surgical methods to prevent rebleeding from diverticulosis, angioectasia, and chronic hemorrhagic radiation proctopathy is reviewed. In addition, the evidence for endoscopic clipping as primary prophylaxis against postpolypectomy bleeding is explored.

Clinical decision-making in managing changes in gastrointestinal function following cancer therapies: Is experience enough?

In patients with gastrointestinal (GI) disorders, identical symptoms may occur for many different reasons. This prospective study assessed whether experienced clinicians can predict accurately the underlying diagnosis or diagnoses contributing to specific symptoms based on the history and physical examination. Three clinicians assessed 47 patients referred for management of troublesome GI symptoms identified after treatment for cancer. Investigations were requested following our comprehensive, peer-reviewed algorithm. The clinicians then recorded their predictions as to the results of those investigations. After each patient had completed all their investigations, had received optimal management and had been discharged from the clinic, the predicted diagnoses were compared to those made. The clinicians predicted 92 diagnoses (1.9 per patient). After investigation, a total of 168 unique diagnoses were identified (3.5 per patient). Of the 92 predicted diagnoses, 41 (43%) matched the diagnosis. Of the 168 actual diagnoses identified, only 24% matched the prediction. None of the clinicians predicted the correct combination of diagnoses contributing to bowel symptoms. Clinical acumen alone is inadequate at determining cause for symptoms in patients with GI symptoms developing after cancer therapy.

The surgical management of radiation proctopathy.

BACKGROUND: There is sparse evidence guiding the optimum surgical management of patients with radiation proctopathy (RP). The purpose of this review is to analyse all the literature on the surgical management of RP in order to guide physicians and surgeons as to when and what surgery should be employed for these patients. METHODS: A literature search of PubMed, EMBASE, MEDLINE, Ovid, and Cochrane Library using the MeSH terms "radiation proctopathy", "proctitis", "surgical management", and related terms as keywords was performed. The review included all articles that reported on the surgical management of patients with radiation proctopathy. All relevant articles were cross-referenced for further articles and any unavailable online were retrieved from hard-copy archive libraries. Eighteen studies including one prospective cohort study, fifteen retrospective cohort studies, and three small case series are included. CONCLUSION: Surgery is indicated for patients with RP for rectal obstruction, perforation, fistulae, or a failure of medical measures to control the symptoms of RP. Surgery centres mainly on diversion version resection. Diversion alone does not remove the damaged tissue leaving the patient at risk of continued complications including bleeding, perforation, occlusion, and abscess formation; however, major resectional surgery carries higher risks. Morbidity and mortality vary 0-44% and 0-11% for diversion only versus 0-100% and 0-14% for resectional surgery. There is no universally agreed surgical first-line approach. The data supports both resection with defunctioning stoma or diversion only as reasonable first-line surgical options for patients requiring surgery for RP.

The stratification of severity of acute radiation proctopathy after radiotherapy for cervical carcinoma using diffusion-weighted MRI.

OBJECTIVE: To determine whether diffusion-weighted imaging (DWI) can be used for quantitatively evaluating severity of acute radiation proctopathy after radiotherapy for cervical carcinoma. MATERIALS AND METHODS: One hundred and twenty-four patients with cervical carcinoma underwent MR examination including DWI before and after radiotherapy. Acute radiation proctopathy was classified into three groups (grade 0, grade I-II and grade III-IV) according to Toxicity Criteria of the Radiation Therapy Oncology Group (RTOG). The pretreatment ADC (ADCpre), ADC after treatment (ADCpost) and ADC change (ΔADC) were compared among three groups. In addition, acute radiation proctopathy was classified into good-prognosis group and poor-prognosis group. ADCpre, ADCpost and ΔADC were compared between two groups. For DWI parameter that had significant difference, discriminatory capability of the parameter was determined using receiver operating characteristics (ROC) analysis. RESULTS: ADCpost and ΔADC were higher in grade I-II group than in grade 0 group (p<0.05), yielding a sensitivity of 79.3% and specificity of 69.4% for ADCpost, and 85.1%, 72.3% for ΔADC for discrimination between two groups. ADCpost and ΔADC were higher in grade III-IV group than in grade I-II group (p<0.05), yielding a sensitivity of 80.3% and specificity of 72.5% for ADCpost, and 84.1%, 74.5% for ΔADC for discrimination between two groups. ADCpost and ΔADC were higher in poor-prognosis group than in good-prognosis group (p<0.05), yielding a sensitivity of 79.5% and specificity of 73.4% for ADCpost, and 87.2%, 78.3% for ΔADC for discrimination between two groups. CONCLUSION: Diffusion-weighted MRI can be used for quantitative stratification of severity of acute radiation proctopathy, which serves as an important basis for appropriate timely adjustment of radiotherapy for cervical carcinoma in order to maximally reduce the radiation injury of rectum.

Endoscopic and non-endoscopic approaches for the management of radiation-induced rectal bleeding.

Pelvic radiation is a commonly utilized treatment for malignancy of the genitourinary and lower gastrointestinal tract. Radiation proctitis and the resultant clinical picture varies from asymptomatic to potentially life threatening. Similarly, treatment options also vary greatly, from medical therapy to surgical intervention. Commonly utilized medical therapy includes sucralfate enemas, antibiotics, 5-aminosalicylic acid derivatives, probiotics, antioxidants, short-chain fatty acids, formalin instillation and fractionated hyperbaric oxygen. More invasive treatments include endoscopic-based, focally ablative interventions such as dilation, heater and bipolar cautery, neodymium/yttrium aluminum garnet argon laser, radiofrequency ablation or argon plasma coagulation. Despite its relatively common frequency, there is a dearth of existing literature reporting head-to-head comparisons of the various treatment options via a randomized controlled approach. The purpose of our review was to present the reader a consolidation of the existing evidence-based literature with the goal of highlighting the comparative effectiveness and risks of the various treatment approaches. Finally, we outline a pragmatic approach to the treatment of radiation proctitis. In light of the lack of randomized data, our goal is to pursue as least invasive an approach as possible, with escalation of care tailored to the severity of the patient's symptoms. For those cases that are clinically asymptomatic or only mildly symptomatic, observation or medical management can be considered. Once a patient fails such management or symptoms become more severe, invasive procedures such as endoscopically based focal ablation or surgical intervention can be considered. Although not all recommendations are supported by level I evidence, reported case series and single-institutional studies in the literature suggest that successful treatment with cessation of symptoms can be obtained in the majority of cases.

Chronic radiation proctopathy: A practical review of endoscopic treatment.

Chronic radiation proctopathy (CRP) is a troublesome complication of pelvic radiotherapy. The most common presentation is rectal bleeding. CRP symptoms interfere with daily activities and decrease quality of life. Rectal bleeding management in patients with CRP represents a conundrum for practitioners. Medical therapy is ineffective in general and surgical approach has a high morbid-mortality. Endoscopy has a role in the diagnosis, staging and treatment of this disease. Currently available endoscopic modalities are formalin, potassium titanyl phosphate laser, neodymium:yttrium-aluminum-garnet laser, argon laser, bipolar electrocoagulation (BiCAP), heater probe, band ligation, cryotherapy, radiofrequency ablation and argon plasma coagulation (APC). Among these options, APC is the most promising.

Emerging indications of endoscopic radiofrequency ablation.

INTRODUCTION: Radiofrequency ablation (RFA) is a well-validated treatment of dysplastic Barrett's esophagus. Other indications of endoscopic RFA are under evaluation. RESULTS: Four prospective studies (total 69 patients) have shown that RFA achieved complete remission of early esophageal squamous intra-epithelial neoplasia at a rate of 80%, but with a substantial risk of stricture. In the setting of gastric antral vascular ectasia, two prospective monocenter studies, and a retrospective multicenter study, (total 51 patients), suggest that RFA is efficacious in terms of reducing transfusion dependency. In the setting of chronic hemorrhagic radiation proctopathy, a prospective monocenter study and a retrospective multicenter study (total 56 patients) suggest that RFA is an efficient treatment. A retrospective comparative study (64 patients) suggests that RFA improves stents patency in malignant biliary strictures. CONCLUSIONS: Endoscopic RFA is an upcoming treatment modality in early esophageal squamous intra-epithelial neoplasia, as well as in gastric, rectal, and biliary diseases.

Radiofrequency ablation using BarRx for the endoscopic treatment of radiation proctopathy: a series of three cases.

Radiation proctopathy is a complication of pelvic radiotherapy, which occurs in patients treated for carcinoma of the prostate, rectum, urinary bladder, cervix, uterus, and testes. If it presents within 6 weeks to 9 months after therapy, it is called acute radiation proctitis/proctopathy (ARP), and if it occurs 9 months to a year after treatment, it is classified as chronic radiation proctitis/proctopathy (CRP). CRP occurs in 5%-20% of patients receiving pelvic radiation, depending on the radiation dose and the presence or absence of chemotherapy. In many cases, CRP resolves spontaneously, but in some, it can lead to persistent rectal bleeding. Other symptoms of CRP include diarrhea, mucoid discharge, urgency, tenesmus, rectal pain, and fecal incontinence. Despite the availability of several therapies, many patients fail to respond, and continue to suffer in their quality of life. Radiofrequency ablation (RFA) is a newer endoscopic technique that uses radiofrequency energy to ablate tissue. This is an emerging way to treat radiation proctopathy and other mucosal telangiectasia. We present three cases of radiation proctopathy treated with RFA at our institute and review the literature on treatment modalities for CRP. We were also able to find 16 other cases of CRP that used RFA, and review their literature as well as literature on other treatment modalities.

Is "pelvic radiation disease" always the cause of bowel symptoms following prostate cancer intensity-modulated radiotherapy?

BACKGROUND: Pelvic radiation disease (PRD) also widely known as "radiation proctopathy" is a well recognised late side-effect following conventional prostate radiotherapy. However, endoscopic evaluation and/or specialist referral for new or persistent post-prostate radiotherapy bowel symptoms is not routine and serious diagnoses may potentially be missed. Here we report a policy of endoscopic evaluation of bowel symptoms persisting >90 days post radiotherapy for prostate cancer. METHODS AND MATERIALS: A consecutive series of 102 patients who had radical prostate intensity-modulated radiotherapy (IMRT)/image-guided radiotherapy (IGRT) and who had new or ongoing bowel symptoms or positive faecal occult blood tests (FOBT) on follow up visits more than three months after treatment, were referred for endoscopic examination. All but one (99%) had full colonoscopic investigation. RESULTS: Endoscopic findings included gastric/colonic/rectal polyps (56%), diverticular disease (49%), haemorrhoids (38%), radiation proctopathy (29%), gastritis/oesophagitis (8%) and rarer diagnoses, including bowel cancer which was found in 3%. Only four patients (4%) had radiation proctopathy without associated pathology and 65 patients (63%) had more than one diagnosis. If flexible sigmoidoscopy alone were used, 36.6% of patients and 46.6% patients with polyp(s) would have had their diagnoses missed. CONCLUSIONS: Our study has shown that bowel symptoms following prostate IMRT/IGRT are due to numerous diagnoses other than PRD, including malignancy. Routine referral pathways should be developed for endoscopic evaluation/specialist review for patients with new or persistent bowel symptoms (or positive FOBT) following prostate radiotherapy. This recommendation should be considered for incorporation into national guidelines.