Chronic radiation proctitis

Surgical complications of oncological treatments: A narrative review

Gastrointestinal complications are common in patients undergoing various forms of cancer treatments, including chemotherapy, radiation therapy, and molecular-targeted therapies. Surgical complications of oncologic therapies can occur in the upper gastrointestinal tract, small bowel, colon, and rectum. The mechanisms of action of these therapies are different. Chemotherapy includes cytotoxic drugs, which block the activity of cancer cells by targeting intracellular DNA, RNA, or proteins. Gastrointestinal symptoms are very common during chemotherapy, due to a direct effect on the intestinal mucosa resulting in edema, inflammation, ulceration, and stricture. Serious adverse events have been described as complications of molecular targeted therapies, including bowel perforation, bleeding, and pneumatosis intestinalis, which may require surgical evaluation. Radiotherapy is a local anti-cancer therapy, which uses ionizing radiation to cause inhibition of cell division and ultimately lead to cell death. Complications related to radiotherapy can be both acute and chronic. Ablative therapies, including radiofrequency, laser, microwave, cryoablation, and chemical ablation with acetic acid or ethanol, can cause thermal or chemical injuries to the nearby structures. Treatment of the different gastrointestinal complications should be tailored to the individual patient and based on the underlying pathophysiology of the complication. Furthermore, it is important to know the stage and prognosis of the disease, and a multidisciplinary approach is necessary to personalize the surgical treatment. The purpose of this narrative review is to describe complications related to different oncologic therapies that may require surgical interventions.

Clinical Features and Management of Acute and Chronic Radiation-Induced Colitis and Proctopathy

BACKGROUND

RICAP is a recognized adverse effect of radiation therapy (RT) that can adversely affect cancer patients' quality of life. Data on the clinical characteristics and outcomes of RICAP are scarce. We aimed to analyze the clinical and endoscopic characteristics of acute or chronic radiation-induced colitis and proctopathy (ARICAP and CRICAP) based on symptom onset after RT (≤ or >45 days, respectively).

METHODS

This is a retrospective observational study of a single tertiary cancer center, from January 2010 and December 2018, of cancer patients with endoscopically confirmed ARICAP and CRICAP. We conducted univariate and multivariate logistic regression analyses to associate clinical variables with endoscopic and medical outcomes.

RESULTS

One hundred and twelve patients were included (84% Caucasian; 55% female; median age of 59 years); 46% had ARICAP with non-bloody diarrhea as the predominant symptom, whereas 55% had CRICAP with mostly bloody diarrhea. Neovascularization was the most frequent finding on endoscopy, followed by bleeding. ARICAP patients more often received medical management (p < 0.001), whereas CRICAP patients with bleeding more often received argon plasma coagulation (APC) (p = 0.002). Female sex and undergoing less-intense RT treatments were more associated with medical treatment; bleeding clinically and during the endoscopy was more associated with APC treatment. However, APC treatment did not significantly reduce bleeding recurrence or RICAP symptoms.

CONCLUSION

Patients with ARICAP and CRICAP experience different symptoms. Medical management should be considered before endoscopic therapy. APC may be useful in patients with endoscopically apparent bleeding.

Argon plasma coagulation therapy in hemorrhagic radiation proctitis following pelvic radiation in gynecological malignancies

Introduction

Chronic radiation proctitis is a common chronic complication of malignant pelvic diseases after pelvic radiation therapy. Although, the incidence has decreased after advent of intensity-modulated radiotherapy due to better control of radiation dose to rectum. In the era of conventional two-field radiotherapy to pelvis, this was a common complication usually presenting after 1-2 years of treatment completion. Rectal bleeding caused by radiation proctitis is difficult to manage. Argon plasma coagulation (APC) is an electrocoagulation technique that appears to be an effective and low-cost alternative to the use of lasers in gastrointestinal endoscopy. The aim of this study was to evaluate the efficacy of APC, as well as patients' tolerance of the procedure, in the treatment of bleeding radiation-induced proctitis.

Materials and Methods

Between January 2015 and August 2017, 29 patients of cancer cervix treated with definite radiotherapy both external and brachytherapy who suffered from rectal bleeding due to radiation proctitis were included for treatment with argon plasma laser (APC). Twenty-three patients suffered from anemia, 16 of whom required blood transfusion. APC was performed, applying the no-touch spotting technique at an electrical power of 40 Watt and an argon gas flow of 1.5-2.0 l/min. Pulse duration was <0.5 s. Treatment sessions were carried out at intervals of 3 weeks. Subjects received 2-4 treatment sessions.

Results

Twenty-eight out of 29 patients were accessible for effects and results. APC led to persistent clinical and endoscopic remission of rectal bleeding after a median of three sessions. No adverse effects were encountered after initial treatment. All the patients were in complete remission.

Conclusions

APC is an effective, safe, and well-tolerated treatment for rectal bleeding caused by chronic radiation proctitis. It should be considered as a first-line therapy for radiation proctitis.

Protective Effect of Bojungikki-Tang against Radiation-Induced Intestinal Injury in Mice: Experimental Verification and Compound-Target Prediction

Bojungikki-tang (BJIT) is a traditional herbal medicine used in Korea, Japan, and China to treat gastrointestinal disorders. In this study, we aimed to investigate whether BJIT has protective effects against radiation-induced intestinal injury and to predict the underlying therapeutic mechanisms and related pathways via network pharmacological analyses. BJIT was injected intraperitoneally (50 mg/kg body weight) to C₃H/HeN mice at 36 and 12 h before exposure to partial abdominal irradiation (5 Gy and 13 Gy) to evaluate the apoptotic changes and the histological changes and variations in inflammatory cytokine mRNA levels in the jejunum, respectively. Through in silico network analysis, we predicted the mechanisms underlying BJIT-mediated regulation of radiation-induced intestinal injury. BJIT reduced the level of apoptosis in the jejunal crypts 12 h post 5-Gy irradiation. Histological assessment revealed intestinal morphological changes in irradiated mice 3.5 days post 13-Gy irradiation. Furthermore, BJIT decreased inflammatory cytokine levels following radiation exposure. Apoptosis, TNF, p53, VEGF, toll-like receptor, PPAR, PI3K-Akt, and MAPK signaling pathways, as well as inflammatory bowel disease (IBD), were found to be linked to the radioprotective effects of BJIT against intestinal injury. According to our results, BJIT exerted its potential protective effects by attenuating histopathological changes in jejunal crypts and suppressing inflammatory mediator levels. Therefore, BJIT is a potential therapeutic agent that can treat radiation-induced intestinal injury and its associated symptoms.

Analysis of Treatment Outcomes and Prognosis After Concurrent Chemoradiotherapy for Locally Advanced Cervical Cancer

The aims of this study were to investigate the short-term and long-term efficacies and chronic radiotoxicity of concurrent chemoradiotherapy (CCRT) combined with image-guided adaptive brachytherapy (IGABT) in patients with locally advanced cervical cancer (LACC) and identify prognostic factors in this patient population. The clinical data of 204 patients with cervical cancer who completed CCRT and subsequent brachytherapy in our hospital between February 2015 and March 2017 were retrospectively analyzed. Short-term and long-term outcomes, chronic radiotoxicity, and prognostic factors were assessed. The median follow-up was 61.1 months. The short-term objective response (OR) rate was 85%. Lymph node metastasis before treatment was an independent predictor of OR (HR = 6.290, 95% CI: 2.211-17.897, p = 0.001). Fifty-two patients developed recurrence, with a median recurrence-free survival of 9.9 months (range, 2.4-52.2 months) and a post-recurrence survival of 12.1 months (range, 2.9-58.1 months). At 3 years, the cumulative incidence of overall recurrence was 26% (95% CI: 17-36). Multivariate analysis showed that Stage IIIB (HR = 2.332, 95% CI: 1.195-4.551, p = 0.013; reference, Stage IIB) and lymph node metastasis (HR = 4.462, 95% CI: 2.365-8.419, p < 0.001) were significant independent predictors of recurrence. Fifty-three patients developed chronic radiation proctitis (CRP). The incidence of severe CRP was approximately 5%, and the average rectal D2cm3 accumulation in patients with severe CRP was 73.4 Gy which is 3.9 Gy higher than that in patients without CRP (p = 0.013). At 4 years, the overall survival (OS) and disease-free survival rates were 65% and 62%, respectively, and lymph node metastasis before treatment was an independent prognostic risk factor for OS. The short-term and long-term efficacies of CCRT combined with IGABT for the treatment of LACC patients were relatively satisfactory. However, the short-term and long-term efficacies of patients with lymph node metastasis before treatment were poor. For patients with lymph node metastasis before treatment, more active individualized treatment strategies should be adopted. When designing a radiotherapy plan, it is necessary to strictly limit the rectal D2cm3 accumulation to prevent serious CRP.

Personalized Radiation Attenuating Materials for Gastrointestinal Mucosal Protection

Cancer patients undergoing therapeutic radiation routinely develop injury of the adjacent gastrointestinal (GI) tract mucosa due to treatment. To reduce radiation dose to critical GI structures including the rectum and oral mucosa, 3D-printed GI radioprotective devices composed of high-Z materials are generated from patient CT scans. In a radiation proctitis rat model, a significant reduction in crypt injury is demonstrated with the device compared to without (p < 0.0087). Optimal device placement for radiation attenuation is further confirmed in a swine model. Dosimetric modeling in oral cavity cancer patients demonstrates a 30% radiation dose reduction to the normal buccal mucosa and a 15.2% dose reduction in the rectum for prostate cancer patients with the radioprotectant material in place compared to without. Finally, it is found that the rectal radioprotectant device is more cost-effective compared to a hydrogel rectal spacer. Taken together, these data suggest that personalized radioprotectant devices may be used to reduce GI tissue injury in cancer patients undergoing therapeutic radiation.

Screening of chronic radiation proctitis and colorectal cancer using periodic total colonoscopy after external beam radiation therapy for prostate cancer

OBJECTIVE

To investigate the incidence of colorectal cancer and chronic radiation proctitis after prostate radiotherapy using periodic total colonoscopy screening.

METHODS

From February 2013 to January 2018, 270 patients who underwent external beam radiation therapy for prostate cancer were advised to receive periodic total colonoscopy screening annually. We evaluated the incidence and characteristics of colorectal cancer and chronic radiation proctitis.

RESULTS

First, second, third, fourth and fifth total colonoscopy were performed in 256 (95%), 151 (56%), 60 (22%), 23 (8.5%) and 7 (2.6%) patients at a median of 14, 31, 42, 54 and 72 months after radiotherapy, respectively. The prevalence proportion of colorectal cancer in the first colonoscopy since radiotherapy was 3.9%. Twelve (4.4%) patients were diagnosed with colorectal cancer, including four invasive cancers, during a follow-up period. Eight of these 12 patients had not experienced rectal bleeding. The median time to diagnosis of colorectal cancer was 21 months. Chronic radiation proctitis was observed in 136 (50%) patients, including 67 (25%) patients with symptomatic bleeding.

CONCLUSIONS

The high detection rate of asymptomatic radiation proctitis suggests the utility of total colonoscopy to screen for early-stage colorectal cancer prior to or following radiotherapy for prostate cancer. Considering the longevity after localized prostate cancer treatment, the awareness of chronic radiation-induced proctitis and the risk of colorectal cancer masked by bleeding is needed in treatment decision -making.

Management of Long-Term Toxicity From Pelvic Radiation Therapy

Pelvic radiation therapy is an integral component in the treatment of various gastrointestinal, gynecologic, and genitourinary cancers. As survival rates from these malignancies improve, the prevalence of toxicity secondary to pelvic radiation has increased. Gastrointestinal toxicities are the most common complications and greatly impact quality of life. Toxicities can present in acute or late stages; although symptoms may be similar during both, the management may differ. Acute toxicities represent an inflammatory reaction in response to the radiation exposure, whereas late toxicities may arise as a result of small vessel disease, ischemia, and fibrosis. Currently, there are no large clinical trials and only limited guidelines on the management of late gastrointestinal radiation toxicities. Therapy is generally approached in a stepwise manner from medical to endoscopic to surgical methods. Several endoscopic therapies, such as the treatment of radiation proctitis with argon plasma coagulation and dilation of radiation bowel strictures, may prevent the need for surgical intervention, which may be associated with high morbidity and mortality. Given that late toxicities can occur years after radiation therapy, they are often difficult to recognize and diagnose. Successful management of late toxicities requires recognition, an understanding of the underlying pathophysiology, and a multidisciplinary approach. More dedicated research could clarify the prevalence of gastrointestinal pelvic radiation toxicities, permit a better understanding of the efficacy and safety profile of current therapies, and allow for the development of novel therapeutic approaches.

Short and long term response to argon plasma therapy for hemorrhagic radiation proctitis

INTRODUCTION

hemorrhagic radiation proctitis appears secondary to radiotherapy. Argon plasma is an effective, safe and easy-to-use technique with a relatively low cost.

OBJECTIVES

to describe the short- and long-term response to argon plasma therapy in patients with hemorrhagic radiation proctitis.

METHOD

an observational prospective study was performed of a series of 82 patients with hemorrhagic radiation proctitis, attended at the National Center for Minimally Invasive Surgery between 2010 and 2016. Summary measurements and a comparison of means (paired Student's t-test) for the final and initial hemoglobin levels were used. In addition, the Kaplan-Meier method was used to determine the rectal bleeding recurrence free time.

RESULTS

in the present study, 54.9% of cases required 1-3 argon sessions and 86.6% required 1-5 sessions to resolve the bleeding, with a median of 3.0 sessions. In addition, 4.9% of patients had proctalgia as a complication. There was an improvement in hemoglobin of 2 g/dl. Rectal bleeding recurrence occurred in 8.5% of the patients during the nine months after therapy. Bleeding recurrence free time at three, six and nine months was 98.8%, 96.3% and 91.5%, respectively. Short-term therapy response was observed in all patients and long-term response after one year of follow-up was 91.5%.

CONCLUSION

argon plasma coagulation shows a good short- and long-term response with few therapy sessions and a low rate of complications in patients with chronic hemorrhagic radiation proctitis.

Efficacy and safety of radiofrequency ablation for treatment of chronic radiation proctitis: A systematic review and meta-analysis

BACKGROUND AND AIM

Although argon plasma coagulation is the current standard endoscopic treatment for chronic radiation proctitis (CRP), radiofrequency ablation (RFA) has emerged as an attractive alternative. The aim of this study is to evaluate the efficacy and safety of RFA for the treatment of CRP.

METHODS

Searches of PubMed, EMBASE, Web of Science, and Cochrane Library databases were performed from 2004 through March 2018. Review and data abstraction were performed independently by two authors. Measured outcomes included hemoglobin, transfusion dependence, number of treatment sessions, RFA settings, and serious adverse events.

RESULTS

Six studies (n = 71; mean age 73.41 ± 1.88 years; 90.14% male) were included. Thirty-eight percent of patients failed prior treatment with argon plasma coagulation. Patients underwent a mean of 1.71 ± 0.34 RFA sessions with 24.54 ± 16.47 RFA applications per session. Pooled clinical and endoscopic success of RFA was 99% (95% confidence interval [CI]: 90-100; P < 0.001) and 100% (95% CI: 94-100; P < 0.001), respectively. Serious adverse events were reported in one patient-pooled rate of 0% (95% CI: 0-3; P < 0.001). Mean pre-procedure hemoglobin was 10.38 ± 1.82 g/dL with significant improvement observed post-RFA [weighted mean difference 2.49 g/dL (95% CI: 2.16-2.82; P < 0.001)]. Among transfusion-dependent patients, 85% (95% CI: 68-97; P < 0.001) became transfusion-free post-RFA. Pooled mean follow-up was 19.73 ± 9.72 months.

CONCLUSION

Despite limited long-term data on RFA for CRP, available evidence suggests RFA is an effective and safe treatment.

Definitive, intensity modulated tomotherapy with a simultaneous integrated boost for prostate cancer patients - Long term data on toxicity and biochemical control

Aim

To report long-term data regarding biochemical control and late toxicity of simultaneous integrated boost intensity modulated radiotherapy (SIB-IMRT) with tomotherapy in patients with localized prostate cancer.

Background

Dose escalation improves cancer control after curative intended radiation therapy (RT) to patients with localized prostate cancer, without increasing toxicity, if IMRT is used.

Materials and methods

In this retrospective analysis, we evaluated long-term toxicity and biochemical control of the first 40 patients with intermediate risk prostate cancer receiving SIB-IMRT. Primary target volume (PTV) 1 including the prostate and proximal third of the seminal vesicles with safety margins was treated with 70 Gy in 35 fractions. PTV 2 containing the prostate with smaller safety margins was treated as SIB to a total dose of 76 Gy with 2.17 Gy per fraction. Toxicity was evaluated using an adapted CTCAE-Score (Version 3).

Results

Median follow-up of living patients was 66 (20-78) months. No late genitourinary toxicity higher than grade 2 has been reported. Grade 2 genitourinary toxicity rates decreased from 58% at the end of the treatment to 10% at 60 months. Late gastrointestinal (GI) toxicity was also moderate, though the prescribed PTV Dose of 76 Gy was accepted at the anterior rectal wall. 74% of patients reported any GI toxicity during follow up and no toxicity rates higher than grade 2 were observed. Grade 2 side effects were reported by 13% of the patients at 60 months. 5-year freedom from biochemical failure was 95% at our last follow up.

Conclusion

SIB-IMRT using daily MV-CT guidance showed excellent long-term biochemical control and low toxicity rates.

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.

International validation of the EORTC QLQ-PRT20 module for assessment of quality of life symptoms relating to radiation proctitis: a phase IV study

Background

Although patients experience radiation proctitis post radiotherapy no internationally tested instruments exist to measure these symptoms. This Phase IV study tested the scale structure, reliability and validity and cross-cultural applicability of the EORTC proctitis module (QLQ-PRT23) in patients who were receiving pelvic radiotherapy.

Methods

Patients (n = 358) from six countries completed the EORTC QLQ-C30, QLQ-PRT23 and EORTC Quality of Life Group debriefing questions. Clinicians completed the EORTC Radiation Therapy Oncology Group scale. Questionnaires were completed at four time-points. The module’s scale structure was examined and validated using standard psychometric analysis techniques.

Results

Three items were dropped from the module (QLQ-PRT23 → QLQ-PRT20). Factor analysis identified five factors in the module: bowel control; bloating and gas; emotional function/lifestyle; pain; and leakage. Inter-item correlations were within r = 0.3–0.7. Test-Retest reliability was high. All multi-item scales discriminated between patients showing symptoms and those without symptomology. The module discriminated symptoms from the clinician completed scoring and for age, gender and comorbidities.

Conclusion

The EORTC QLQ-PRT20 is designed to be used in addition to the EORTC QLQ-C30 to measure quality of life in patients who receive pelvic radiotherapy. The EORTC QLQ-PRT20 is quick to complete, acceptable to patients, has good content validity and high reliability.

Trial registration

Australian and New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000972224.

Electronic supplementary material

The online version of this article (10.1186/s13014-018-1107-x) contains supplementary material, which is available to authorized users.

National Population-Based Study Comparing Treatment-Related Toxicity in Men Who Received Intensity Modulated Versus 3-Dimensional Conformal Radical Radiation Therapy for Prostate Cancer

PURPOSE

To compare, in a national population-based study, severe genitourinary (GU) and gastrointestinal (GI) toxicity in patients with prostate cancer who were treated with radical intensity modulated radiation therapy (IMRT) or 3-dimensional conformal radiation therapy (3D-CRT).

METHODS AND MATERIALS

Patients treated with IMRT (n=6933) or 3D-CRT (n=16,289) between January 1, 2010 and December 31, 2013 in the English National Health Service were identified using cancer registry data, the National Radiotherapy Dataset, and Hospital Episodes Statistics, the administrative database of care episodes in National Health Service hospitals. We developed a coding system that identifies severe toxicity (at least grade 3 according to the National Cancer Institute Common Terminology Criteria for Adverse Events scoring system) according to the presence of a procedure and a corresponding diagnostic code in patients' Hospital Episodes Statistics records after radiation therapy. A competing risks regression analysis was used to estimate hazard ratios (HRs), comparing the incidence of severe GI and GU complications after IMRT and 3D-CRT, adjusting for patient, disease, and treatment characteristics.

RESULTS

The use of IMRT, as opposed to 3D-CRT, increased from 3.1% in 2010 to 64.7% in 2013. Patients who received IMRT were less likely than those receiving 3D-CRT to experience severe GI toxicity (4.9 vs 6.5 per 100 person-years; adjusted HR 0.66; 95% confidence interval 0.61-0.72) but had similar levels of GU toxicity (2.3 vs 2.4 per 100 person-years; adjusted HR 0.94; 95% confidence interval 0.84-1.06).

CONCLUSIONS

Prostate cancer patients who received radical radiation therapy using IMRT were less likely to experience severe GI toxicity, and they had similar GU toxicity compared with those who received 3D-CRT. These findings in an unselected "real-world" population support the use of IMRT, but further cost-effectiveness studies are urgently required.

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.

An approach to acute lower gastrointestinal bleeding

Lower gastrointestinal bleeding (LGIB) is a common problem that can be treated via a number of endoscopic, radiological and surgical approaches. Although traditionally managed by the colorectal surgeons, surgery should be considered a last resort given the variety of endoscopic and radiological approaches available. This article provides an overview on the common causes of acute LGIB and the various techniques at our disposal to control it.

Long-term results on the efficacy of argon plasma coagulation for patients with chronic radiation proctitis after conventionally fractionated, dose-escalated radiation therapy for prostate cancer

PURPOSE

This study was designed to assess the efficacy and outcomes of argon plasma coagulation (APC) in the management of chronic radiation proctitis after conventionally fractionated, dose-escalated radiation therapy (≥7560 cGy).

METHODS AND MATERIALS

We retrospectively reviewed the charts on all patients treated with external beam radiation therapy (minimum dose, 7560 cGy) for histologically confirmed prostate cancer at our institution from 2003 to 2011. Five hundred patients met these criteria; of these, 35 patients (7.0%) developed radiation proctitis necessitating intervention with APC. Indications for APC treatment were either the need for blood transfusions resulting from proctitis-related anemia or refractory bleeding despite medical management.

RESULTS

The median follow-up from the completion of radiation treatment was 78 months (range, 19-129) and the median follow up from the most recent APC treatment was 56 months (range, 3-112). Fifteen men (42.9%) needed blood transfusions because of proctitis-related anemia. For 19 patients (54.3%), bleeding was controlled after 1 or 2 treatments. Eventual bleeding control was obtained in 30 patients (85.7%). The median number of sessions per patient was 2 (range, 1-13). Post-APC ulceration was noted in 8 cases (22.9%). Two patients (5.7%) developed colovesicular fistulas, with 1 patient dying from this complication. A short interval between treatments (≤35 days) was associated with an increased risk of ulcer or fistula formation.

CONCLUSIONS

APC is an effective treatment for patients with medically refractive radiation proctitis after dose-escalated radiation therapy, frequently controlling bleeding after only one or two sessions. However, rectal ulceration is a common complication, along with a small risk of life-threatening toxicity.

Effects of L-Glutamine oral supplementation on prostate of irradiated rats

Objectives

To investigate the protective effect of L-Glutamine in animals undergone to ventral radiation when the target organ is not the prostate.

Materials and Methods

Wistar rats were divided into groups of 10 animals each: Controls (C), maintained under standard conditions and not exposed to radiation, Radiated group (R) undergone to abdominal radiation only and Radiated plus supplemented by L-glutamine group (R+G). The animals of group R+G were supplemented with L-glutamine at the beginning of the experiment until death in the 22nd day. The ventral prostate was dissected and processed for morphometrical analysis. The epithelial height, collagen density and acinar area were objectively assessed in histological sections.

Results

Epithelial height was significantly reduced in R group in comparison to C group (p= 0.005). However, there was no statistical difference between the C and R+G groups. Collagen surface density in the C and R groups were not statistically different, but a significant difference was observed when comparing groups R+G and R (p= 0.040). The R+G group values did not differ significantly from C group. The acinar prostate area of group R was similar to that of C (p= 0.971), but in R+G it was significantly reduced when compared with the C (p= 0.038) and R (p= 0.001) groups.

Conclusions

Pelvic radiation promotes structural modifications in ventral prostate of rats, which can be reduced by L-Glutamine.

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.

Systematic Review of the Relationship between Acute and Late Gastrointestinal Toxicity after Radiotherapy for Prostate Cancer

A small but meaningful percentage of men who are treated with external beam radiation therapy for prostate cancer will develop late gastrointestinal toxicity. While numerous strategies to prevent gastrointestinal injury have been studied, clinical trials concentrating on late toxicity have been difficult to carry out. Identification of subjects at high risk for late gastrointestinal injury could allow toxicity prevention trials to be performed using reasonable sample sizes. Acute radiation therapy toxicity has been shown to predict late toxicity in several organ systems. Late toxicities may occur as a consequential effect of acute injury. In this systematic review of published reports, we found that late gastrointestinal toxicity following prostate radiotherapy seems to be statistically and potentially causally related to acute gastrointestinal morbidity as a consequential effect. We submit that acute gastrointestinal toxicity may be used to identify at-risk patients who may benefit from additional attention for medical interventions and close follow-up to prevent late toxicity. Acute gastrointestinal toxicity could also be explored as a surrogate endpoint for late effects in prospective trials.

Treatment-related gastrointestinal toxicities and advanced colorectal or pancreatic cancer: A critical update

Gastrointestinal toxicities (GIT), including oral mucositis, nausea and vomiting, and diarrhea, are common side effects of chemotherapy and targeted agents in patients with advanced colorectal cancer and pancreatic cancer. Being often underreported, it is still difficult to precisely establish their burden in terms of both patient’s quality of life and cancer care costs. Moreover, with the use of more intensive upfront combination regimens, the frequency of these toxicities is rapidly growing with a potential negative effect also on patient’s outcome, as a result of dose reductions, delays or even discontinuation of active treatments. Thus, identifying patients at higher risk of developing GIT as well as an optimal management are paramount in order to improve patient’s compliance and outcome. After the description of the main treatment-induced GIT, we discuss the current knowledge on the pathophysiology of these side effects and comment the scales commonly used to assess and grade them. We then provide a critical update on GIT incidence based on the results of key randomized trials conducted in patients with metastatic colorectal cancer and advanced pancreatic cancer.

Differential Diagnosis of Colonic Strictures: Pictorial Review with Illustrations from Computed Tomography Colonography

Strictures of the colon can lead to significant morbidity requiring surgical management. The etiology of strictures is broad and generally categorized as benign, malignant, or pseudostrictures. Computed tomography (CT) is a crucial imaging modality in the assessment and characterization of colonic pathologies but colonoscopy remains the diagnostic gold standard. However, in the setting of incomplete colonoscopy due to strictures, the imaging features of CT will be relied on. This review will focus on the CT features of different colon pathologies leading to strictures and will be illustrated with images from 10 years of experience with CT colonography at our institutions from 2002-2012 (Hotel Dieu Hospital, Queen's University and Mount Sinai Hospital, University of Toronto).

Pathogenesis, diagnosis, and management of ulcerative proctitis, chronic radiation proctopathy, and diversion proctitis

Chronic proctitis refers to persistent or relapsing inflammation of the rectum, which results from a wide range of etiologies with various pathogenic mechanisms. The patients may share similar clinical presentations. Ulcerative proctitis, chronic radiation proctitis or proctopathy, and diversion proctitis are the 3 most common forms of chronic proctitis. Although the diagnosis of these disease entities may be straightforward in the most instances based on the clinical history, endoscopic, and histologic features, differential diagnosis may sometimes become problematic, especially when their etiologies and the disease processes overlap. The treatment for the 3 forms of chronic proctitis is different, which may shed some lights on their pathogenetic pathway. This article provides an overview of the latest data on the clinical features, etiologies, diagnosis, and management of ulcerative proctitis, chronic radiation proctopathy, and diversion proctitis.

Postradiation changes in tissues: evaluation by imaging studies with emphasis on fluorodeoxyglucose-PET/computed tomography and correlation with histopathologic findings

Efforts have been made to minimize the damage to adjacent normal tissues during radiotherapy, primarily by shifting from the use of conventional radiotherapy to more advanced techniques. Reviewing the overall pattern on combined anatomic and functional imaging can enhance diagnostic accuracy. Several radiotracers can be used; [(18)F]fluorodeoxyglucose is the most common. Familiarity with the type and timing of previous radiation therapy, the spectrum of imaging findings after radiation injury, and the appropriate use of the different radiotracers can be crucial. This article summarizes postradiation histologic findings and multimodality imaging findings, with emphasis on PET/computed tomography.

Assessing patients' perceived bother from the gastrointestinal side effects of radiotherapy for localized prostate cancer: initial questionnaire development and validation

BACKGROUND

The present study reports on the development and first steps of validation of the Gastrointestinal Side Effects Questionnaire (GISEQ), a measure of patient-reported gastrointestinal symptoms following local radiotherapy to the prostate. The questionnaire design provides a novel approach of assessment of side effects of prostate radiotherapy, by enabling measurement of patient-perceived change in symptoms.

MATERIAL AND METHODS

The eight-item GISEQ was administered to 130 prostate cancer patients referred to radiotherapy. Patients completed the GISEQ at four, eight and 15 weeks after start of radiotherapy. The psychometric properties including validity, reliability, responsiveness and feasibility were evaluated. The EORTC QLQ-C30 and QLQ-PR25 were chosen as comparative measures.

RESULTS

Expert opinion supported content validity. For concurrent validity, correlation between the GISEQ and matching items in the EORTC questionnaires was moderate but significant (r > 0.41, p < 0.001). The responsiveness was adequate, indicated by changes in GISEQ scores over time corresponding to the effects of radiation. Internal consistency was satisfactory (overall Cronbach's α> 0.70). Sensitivity and specificity for items diarrhea, constipation and blood in stools ranged from 50% to 100% and from 68% to 100%, respectively. All items had a floor effect above 15%. The response rates ranged from 85% to 92% and missing items was < 0.8%, indicating good feasibility.

CONCLUSIONS

The GISEQ showed satisfactory internal consistency and adequate content validity, concurrent validity and responsiveness. It is brief, easy to use and can be quickly evaluated, making it useful not only for research but possibly also for clinical settings. Modification of response scale and extension of items are potential improvements. Further work is needed to strengthen the psychometric qualities of the GISEQ and to evaluate its clinical use and potential effects of response shift and recall bias.

Relationship between the severity of diversion colitis and the composition of colonic bacteria: a prospective study

Background/Aims

Diversion colitis is the inflammation of the excluded segment of the colon in patients undergoing ostomy. It has been suggested that a change in colonic flora may lead to colitis; however, direct evidence for this disease progression is lacking. The aim of this study was to evaluate the relationship between the severity of diversion colitis and the composition of colonic bacteria.

Methods

We used culture methods and polymerase chain reaction to analyze the colonic microflora of patients who underwent rectal cancer resection with or without diversion ileostomy. In the diversion group, we also evaluated the severity of colonoscopic and pathologic colitis before reversal.

Results

This study enrolled 48 patients: 26 in the diversion group and 22 in the control group. Significant differences were observed between the two groups in the levels of Staphylococcus (p=0.038), Enterococcus (p<0.001), Klebsiella (p<0.001), Pseudomonas (p=0.015), Lactobacillus (p=0.038), presence of anaerobes (p=0.019), and Bifidobacterium (p<0.001). A significant correlation between the severity of colitis and bacterial composition was only observed for Bifidobacterium (p=0.005, correlation coefficient=-0.531).

Conclusions

The colonic microflora differed significantly between the diversion and control groups. Bifidobacterium was negatively correlated with the severity of diversion colitis.

Clinical and proctoscopic evaluation of topical formalin application in the treatment of chronic radiation proctitis

BACKGROUND AND AIMS

Chronic radiation proctitis is a disease associated with radiotherapy of cancer in the pelvic region. The main symptom is rectal bleeding. Several treatment modalities have been attempted, but few have demonstrated satisfactory effects. We present our experience with formalin applied locally to the rectal mucosa in the treatment of chronic radiation proctitis. Furthermore, we assess possible complications, the gravest suggested being cancer. Previous studies on the subject have reported good results, but often with a somewhat vaguely defined follow-up. Our evaluation of the treatment was based on both subjective symptoms and proctoscopic findings.

MATERIAL AND METHODS

A small study (N = 11) was conducted retrospectively. All patients treated for chronic radiation proctitis with formalin in our clinic were identified, and data concerning effect and complications were collected by studying the patients' records, with a questionnaire and a follow-up interview and proctoscopy.

RESULTS

The study showed a marked decrease in bleeding and objective signs of proctitis in all patients. Complete cessation of bleeding was achieved in five patients. Possible complications to the treatment detected in our study were the following: anorectal pain, tenesmus, incontinence, diarrhea, and mucous rectal discharge. No signs of neoplasia were found.

CONCLUSIONS

The formalin treatment had a very good effect on chronic radiation proctitis. Possible complications were detected. Except in the case of anorectal pain, these are all of a questionable nature and can possibly be attributed to chronic radiation proctitis itself rather than the formalin treatment. Further study is warranted to confirm long-term effects of the formalin and to exclude possible complications, especially secondary anorectal cancer.

Trans-anal rectoscopic ball diathermy (TARD) for radiotherapy-induced haemorrhagic telangiectasia: a safe and effective treatment

AIM

Rectal bleeding may occur late after radiotherapy for prostate or bladder cancer, particularly when given by external beam, due to radiotherapy-induced haemorrhagic telangiectasia (RIHT). We present the results of trans-anal rectoscopic ball diathermy (TARD) for RIHT.

METHOD

Data were collected from patients who received TARD for RIHT. The diagnosis was made during endoscopic examination. Treatment involved discretely spaced spot monopolar diathermy coagulation of the rectal mucosa to the affected areas.

RESULTS

Thirteen patients [median age 76 (69-80) years] underwent TARD for RIHT between 2005 and 2008. All presented late with rectal bleeding following radiotherapy for prostate or bladder cancer. Eight were treated as a day case, four remained in hospital for one night and one was hospitalized for 2 days. There was no mortality. Eleven patients achieved excellent symptomatic control requiring no further treatment at a median follow-up of 20 (3-36) months. One patient underwent further TARD for recurrence. One patient complained of severe anorectal pain of no obvious cause and one developed constipation.

CONCLUSION

Trans-anal rectoscopic ball diathermy (TARD) is a safe and effective treatment for patients with rectal bleeding due to RIHT.

Hemorrhoid management in patients with radiation proctitis

PURPOSE

Management of rectal bleeding in patients with radiation proctitis presents a conundrum for practitioners. Surgeons are appropriately concerned about using conventional methods of treatment in these patients, such as cautery for bleeding areas in the rectum, rubber band ligation, or excision of internal and/or external hemorrhoids, for fear of poor healing and possible exacerbation of the original problem. Few randomized controlled trials are available on the treatment of radiation proctitis alone, and no literature exists pertaining to the management of symptomatic hemorrhoids in the radiated patient.

METHODS

In the absence of observational studies, the authors created an email survey to distribute to the membership of the American Society of Colon and Rectal Surgeons in order to try to identify current management practices for radiation proctitis and for the treatment of their symptomatic hemorrhoids.

RESULTS

Of the 327 respondents, 85 % favored the use of topical formalin to treat radiation proctitis, while 42 % additionally used argon plasma coagulation. Only 25 % of practitioners report using sucralfate, though existing data on this therapy are promising. Regarding the management of hemorrhoids in patients with a history of rectal irradiation, 55 % of respondents hoped treatment of radiation proctitis alone would solve the problem. Forty-three percent reported using rubber band ligation, 30 % using hemorrhoidectomy, and 18 % using sclerotherapy.

CONCLUSIONS

While most respondents treated radiation proctitis alone in patients with symptomatic hemorrhoids, many also felt rubber band ligation, hemorrhoidectomy, and sclerotherapy are safe and effective alternative therapies in this population.

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.

Argon plasma coagulation for the treatment of hemorrhagic radiation colitis

Radiation colitis is a common consequence of pelvic radiation. Its complications may include anemia due to chronic bleeding requiring transfusions. Many of these patients are managed with rectal medications which are often inadequate for control. Argon plasma coagulation (APC) has been well described for its efficacy in treating radiation proctitis. Here we present two cases in whom APC therapy was used to treat severe radiation colitis. We reviewed two cases originally seen at the regional cancer center (Cross Cancer Institute) in Edmonton, Alberta, Canada. Both patients received pelvic radiation for recurrent endometrial cancers and were referred for active bleeding secondary to radiation colitis that had required numerous transfusions. Radiation-induced telangiectasias were found from 10–50 cm in the sigmoid colon. Both patients had significant improvement of symptoms after one session of APC treatment set at 40–60 W and gas flow of 2.0 l/min. There were no complications from the procedures. Neither patient required blood transfusions after the treatment with improvement in their hemoglobin levels and were doing well at 3- and 6-month follow-up. APC can be used effectively to provide immediate and sustained resolution of symptoms in patients with radiation colitis.

Gene expression analysis in chronic postradiation proctopathy

PURPOSE

Radiotherapy is one of the important treatment modalities for tumors of pelvic organs. The fixed location of the rectum and its anatomic relationship with other pelvic organs makes it prone to radiation injury resulting in chronic radiation proctopathy in 5% to 20% of patients. Endothelial dysfunction has been associated with a number of pathophysiological processes. Endothelial cells synthesize and release various factors that regulate angiogenesis, inflammatory responses, hemostasis, as well as vascular tone and permeability.

METHODS

Rectum tissue samples from 20 patients with established chronic radiation proctopathy were analysed for the expression of genes related to oxidative stress, tissue hypoxia, angiogenesis, and inflammation [endoglin (ENG), activin receptor-like kinase 1 (ALK1), platelet endothelial cell adhesion molecule 1 (PECAM), vascular endothelial growth factor (VEGF), fibroblast growth factor 2 (FGF2), hypoxia-inducible factor 1 (HIF-1), and interleukin-1 beta (IL-1β)].

RESULTS

Overexpression of HIF-1, VEGF, FGF2, and IL-1β was detected in affected tissue. For the first time, a significant suppression of activin receptor-like kinase 1 and ENG could be revealed.

CONCLUSION

The data provided here allow further insight into the pathogenesis of radiation-induced rectum injury. Radiation-induced damage is not confined to a single event but involves complex signaling between different pathways, enhancing and maintaining the processes that lead to mucosal damage. The results indicate that postradiation tissue hypoxia is critical for fibrosis, which involves changes in the expression of profibrotic and angiogenic factors in rectal tissue.

A mechanism for abnormal angiogenesis in human radiation proctitis: analysis of expression profile for angiogenic factors

BACKGROUND

Radiation proctitis is an increasingly prevalent problem, with many patients being treated with radiotherapy for pelvic cancers. However, the mechanisms by which radiation proctitis develops in humans are not well understood. In this study, the expression profiles of angiogenic factors were analyzed to clarify their role in the etiology of radiation proctitis.

METHODS

Rectal biopsies were taken from 8 patients with radiation proctitis and 8 normal subjects. Protein lysates of the tissues were applied to an antibody array for angiogenesis-related factors. The mRNA level of each factor was evaluated by Taqman real-time PCR. Immunohistochemistry was performed using the labeled streptavidin biotin method.

RESULTS

Antibody array analysis revealed 2.12- to 7.31-fold higher expression levels of angiogenin, fibroblast growth factor 1 (FGF1), endoglin, matrix metalloproteinase (MMP)-8, urokinase-type plasminogen activator (uPA) and maspin in radiation proctitis tissues compared with normal rectal mucosa. The mRNA level of each factor in radiation proctitis tissue was significantly higher than in normal rectal mucosa, suggesting their transcriptional activation. Immunohistochemical staining showed strong expression of angiogenin and maspin in rectal epithelia, MMP-8 and uPA in infiltrating lymphocytes, FGF1 in fibroblasts and endoglin in endothelial cells. The expression of VEGF was not evident.

CONCLUSIONS

Our results suggest that in radiation proctitis, MMP-8 and uPA cooperatively degrade the extracellular matrix and basement membrane to provide space for angiogenesis. Simultaneously, angiogenin and FGF1 promote endothelial cell proliferation, and endoglin induces vessel formation, culminating in angiogenesis. Inhibitors of angiogenic factors such as angiogenin and FGF1 may be effective for treating radiation proctitis.

Radiation proctitis: current strategies in management

Radiation proctitis is a known complication following radiation therapy for pelvic malignancy. The majority of cases are treated nonsurgically, and an understanding of the available modalities is crucial in the management of these patients. In this paper, we focus on the current treatments of radiation proctitis.

Endoscopic management of chronic radiation proctitis

Chronic radiation proctopathy occurs in 5%-20% of patients following pelvic radiotherapy. Although many cases resolve spontaneously, some lead to chronic symptoms including diarrhea, tenesmus, urgency and persistent rectal bleeding with iron deficiency anemia requiring blood transfusions. Treatments for chronic radiation proctitis remain unsatisfactory and the basis of evidence for various therapies is generally insufficient. There are very few controlled or prospective trials, and comparisons between therapies are limited because of different evaluation methods. Medical treatments, including formalin, topical sucralfate, 5-amino salicylic acid enemas, and short chain fatty acids have been used with limited success. Surgical management is associated with high morbidity and mortality. Endoscopic therapy using modalities such as the heater probe, neodymium:yttrium-aluminium-garnet laser, potassium titanyl phosphate laser and bipolar electrocoagulation has been reported to be of some benefit, but with frequent complications. Argon plasma coagulation is touted to be the preferred endoscopic therapy due to its efficacy and safety profile. Newer methods of endoscopic ablation such as radiofrequency ablation and cryotherapy have been recently described which may afford broader areas of treatment per application, with lower rate of complications. This review will focus on endoscopic ablation therapies, including such newer modalities, for chronic radiation proctitis.

Antioxidant properties of probiotics and their protective effects in the pathogenesis of radiation-induced enteritis and colitis

Radiation therapy has become one of the most important treatment modalities for human malignancy, but certain immediate and delayed side-effects on the normal surrounding tissues limit the amount of effective radiation that can be administered. After exposure of the abdominal region to ionizing radiation, nearly all patients experience transient symptoms of irradiation of the bowel. Acute-phase symptoms may persist for a short time, yet long-term complications can represent significant clinical conditions with high morbidity. Data from both experimental studies and clinical trials suggest the potential benefit for probiotics in radiation-induced enteritis and colitis. On the other hand, it is well evidenced that both useful and harmful effects of therapeutic applications of ionizing radiation upon living systems are ascribed to free-radical production. Therefore, the hypothesis that probiotics reinforce antioxidant defense systems of normal mucosal cells exposed to ionizing radiation may explain to an extent their beneficial action. The aim of this review is threefold: First, to make a short brief into the natural history of radiation injury to the intestinal tract. Second, to describe the primary interaction of ionizing radiation at the cellular level and demonstrate the participation of free radicals in the mechanisms of injury and, third, to try a more profound investigation into the antioxidant abilities of probiotics and prebiotics based on the available experimental and clinical data.

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.

Ulcerative proctitis

Ulcerative proctitis is an idiopathic mucosal inflammatory disease involving only the rectum and is therefore an anatomically limited form of ulcerative colitis. Diagnosis is made based on clinical presentation, endoscopic appearance, and histopathology. Additionally, other etiologies of proctitis are excluded. The course of the disease is variable ranging from complete resolution to easily maintained remission to frequent relapses or refractory disease. Extension of inflammatory changes involving the proximal colon occurs in some cases. Rectal 5-aminosalicylic acid (5-ASA) or steroids are the initial treatments of choice with oral 5-ASA, sulfasalazine, or steroids used for treatment failures or patients unable to tolerate rectally administered drugs. Immunomodulators like azathioprine and 6-mercaptopurine have been used successfully in small groups of patients who have not responded to 5-ASA or steroids. Oral or rectal 5-ASA products maintain remission but long-term steroid use should be avoided. Rare cases may require surgical therapy.

A murine model for the study of molecular pathogenesis of radiation proctitis

PURPOSE

To establish a novel mouse brachytherapy model with which to study the role of inflammation in the pathogenesis of radiation proctitis.

METHODS AND MATERIALS

The distal rectums of BALB/c and C57BL/6 mice were irradiated with three to five fractions of 5.5 to 8 Gy. Tissues were harvested and evaluated for histopathology, using the radiation injury score (RIS). Cytokine mRNA expression was assessed using real-time PCR.

RESULTS

Fifty percent of the mice treated with 22 Gy delivered in four fractions of 5.5 Gy died as a result of anorectal stenosis and distal bowel obstruction prior to the time of scheduled sacrifice, with a latency period of 4 to 10 weeks for the BALB/c and 3 to 4 weeks for the C57BL/6 mice. The RISs were 7, 12, and 8 at 2, 6, and 11 weeks, respectively, in the BALB/c mice and was 8.7 in the C57BL/6 mice on week 6. A 100- to 300-fold increase in interleukin-1beta (IL-1beta) (p = 0.04) and IL-6 mRNA (p = 0.07) and a 5- to 6-fold increase in transforming growth factor (TGF) and tumor necrosis factor-alpha mRNA expression levels (p < 0.001 and p = 0.01) were observed at 2 to 6 weeks after radiation. Cytokine mRNA tissue expression correlated positively with radiation dose (p < 0.0001). The RIS correlated well with IL-1beta and IL-6 mRNA levels in the BALB/c mice and with IL-1beta, IL-6, and TGF mRNA levels in C57BL/6 mice. Analysis of receiver operating characteristic curve showed that IL-1beta and IL-6 have the largest area under the curve and therefore are good markers of radiation proctitis (p < 0.001).

CONCLUSIONS

Radiation-induced proctitis was associated with a dose-dependent, characteristic proinflammatory cytokine response pattern in a novel mouse model suitable for interventional studies.

Late rectal complications after prostate brachytherapy for localized prostate cancer: incidence and management

This review of the literature on late rectal complications after prostate brachytherapy indicated that it is a highly effective treatment modality for patients with clinically localized prostate cancer but can cause chronic radiation proctitis. The most common manifestation of chronic radiation proctitis was anterior rectal wall bleeding, which often occurred within the first 2 years after brachytherapy. It is interesting to note that the rates of late rectal morbidity appear to have declined over time, which may reflect improvements in implantation techniques and imaging. Rectal biopsy as part of the workup to evaluate rectal bleeding can lead to rectal fistula and the need for colostomy, a rare but major complication. The authors recommend 1) screening colonoscopy before brachytherapy for patients who have not had a screening colonoscopy within the preceding 3 years to rule out colorectal malignancies and, thus, facilitate conservative management should rectal bleeding occur; 2) lifestyle modifications during treatment to limit exposure of the rectum to radiation; and 3) conservative management for rectal bleeding that occurs within 2 years after brachytherapy. Cancer 2009. (c) 2009 American Cancer Society.