Radiation Proctitis

Earn CME/CE in your profession:

Continuing Education Activity

Radiation proctitis refers to injury or damage to the rectum secondary to radiation therapy. It is postulated that almost half of all patients with pelvic malignancies undergo treatment that involves radiation. This activity reviews the evaluation and treatment of radiation proctitis and highlights the role of the interprofessional team in managing patients with this condition.


  • Identify the etiology and epidemiology of radiation proctitis.
  • Describe the appropriate evaluation of radiation proctitis.
  • Outline the treatment and management options available for radiation proctitis.
  • Summarize the interprofessional team strategies for improving care coordination and communication to treat radiation proctitis and improve outcomes.


Radiation proctitis refers to injury or damage to the rectum secondary to radiation therapy. It is postulated that almost half of all patients with pelvic malignancies undergo treatment that involves radiation.[1] Due to the improvement in overall survival in patients with cervical, prostate, rectal, and other pelvic cancers, clinicians will encounter increasing numbers of patients experiencing radiation proctitis. Radiation proctitis is divided into acute and chronic, with chronic proctitis occurring greater than six months after initial radiation treatment.


Radiation proctitis occurs as a result of radiation therapy for malignancy to organs in the pelvis, including the prostate, rectum, and reproductive organs. The degree of radiation proctitis is variable, depending on the modality by which the radiation is delivered, as well as its duration and intensity.


It is difficult to assess the true incidence of radiation proctitis. There are several large series that estimate chronic radiation proctitis to be anywhere between 5 and 11%.[2] Almost 90% of patients who go on to experience chronic radiation proctitis will present in the first two years after treatment.[3][4]


Radiation therapy works by damaging cells through the direct effect of ionizing radiation on DNA, lipids, and proteins.[5] Water makes up the majority of the cell, and ionizing radiation results in the creation of oxygen-free radicles. The direct effect of ionizing radiation also disrupts vital cellular proteins and DNA causing cellular necrosis. Early radiation injury causes edema, mucosal hyperemia, and ulceration of the affected tissue.

The epithelium of the bowel is rapidly proliferating, and as such, it is more predisposed to the effects of radiation damage. Chronically, there is intimal proliferation and hyaline thickening of the media of arterioles.[6] Hypertrophy of rectal smooth muscle occurs, which can affect compliance and defecation as the rectum's ability to distend is diminished.[7] This is further worsened by fibrosis of the serosa.

History and Physical

Patients experiencing radiation proctitis may present with malabsorption, perforation, bowel obstruction, bleeding, and stricture formation. They can also present with fistulous disease. If the anal sphincter is directly involved in the radiation field, patients may present with fecal incontinence.

It is important to consider a recurrent malignancy in patients who present several years after their radiation therapy with symptoms of malabsorption, abdominal pain, increased frequency of bowel movements and bleeding, etc. While these symptoms may be due to radiation proctitis, they may also signify a local recurrence.

In terms of physical examination, a focused abdominal examination should be performed and, most importantly, a digital rectal exam to identify any anorectal stenosis. The examination can be painful and may not be able to be performed in the office setting, in which case an examination under anesthesia is indicated.


The first step after completing a thorough history and physical examination is to perform either rigid sigmoidoscopy or flexible sigmoidoscopy. An experienced colorectal surgeon or gastroenterologist should perform this exam with minimal insufflation as the inflamed bowel is more susceptible to perforation, especially as it becomes fixated. The examination is likely to reveal a friable mucosa with a multitude of changes, including edema, oozing, and ulcerations.[8][9]

The mucosa may sometimes appear similar to that which is seen in inflammatory bowel disease with pseudopolyp formation. Areas of ulceration may require a biopsy, but this must be done with caution. There are likely to be multiple areas of strictures that can be indistinguishable from recurrent malignancy.[10]

Barium or water-soluble enema studies may also be performed, which can identify strictures, obstruction, shortening, and narrowing of the rectosigmoid area with loss of the normal curvature. It may also demonstrate decreased compliance of the rectum. The pre-sacral space may appear to be increased due to rectal wall thickening.[11]

Treatment / Management

Formalin (i.e., formaldehyde 4%–10%) has been studied and used to treat chronic radiation proctitis for over 20 years.[12] The advantages of formalin treatment are that it can be utilized in the clinical setting without the need for general anesthesia and only the need for light sedation. The mechanism of action of formalin is the chemical cauterization of the ulcers and telangiectasias, which are the source of bleeding in chronic proctitis. The formalin can be applied with the direct application of a gauze that has been soaked in formalin and the direct application of it to the mucosa of the affected areas, usually under direct vision using rigid proctoscopy. The concentration typically used is 4%, although there are papers that have utilized a 10% solution. A study from Poland showed that after the first application, 50% of the patients had complete resolution of their symptoms, and most patients required an average of 2 treatments.[13] The latest clinical consensus guidelines from the American Society of Colon and Rectal Surgery suggest that short-chain fatty acid enemas are not useful in the treatment of chronic radiation proctitis.[14] Over the years, there have been investigations into other treatments, including ozone therapy, mesalamine, and metronidazole. However, no evidence exists to support their efficacy.[15] Sucralfate enemas have been found helpful in some studies.[16]

Hyperbaric oxygen therapy has reasonable evidence to support its use for radiation proctitis.[17][18] Several studies have demonstrated that endoscopic argon beam plasma coagulation can reduce bleeding by approximately 79 to 100%.[19] While endoscopic argon beam plasma coagulation has been proven, other endoscopic treatments, such as bipolar electrocoagulation, radio-frequency ablation, and Nd-YAG laser, have not been sufficiently studied.[15]

Surgery is reserved for patients who did not show improvement in their symptoms following the above medical and endoscopic interventions. It is also used for some of the more severe complications which are associated with radiation proctitis, including strictures that may lead to large bowel obstruction, fistulas, or even perforation. Studies have estimated that only 10% of patients with radiation proctitis will ultimately require operative intervention.[20] In very severe cases, a proctectomy may be necessary. However, studies have demonstrated that diversion in the form of an ileostomy or colostomy may improve quality of life, and no further surgical procedures may be needed.[21]

Differential Diagnosis

Radiation proctitis should be distinguished from other etiologies of infectious and noninfectious dysentery, which include:

  • Diverticulitis
  • Crohn disease
  • Irritable bowel disease
  • Infectious colitis
  • Recurrence of malignancy


The prognosis depends on the severity of the individual patient's disease. Up to 30% of patients with severe symptoms may have a significant decrease in health-related quality of life.[22] Patients with radiation proctitis are also at risk of developing a secondary malignancy, of which the majority are colon or rectal cancers.[23]


  • Colitis
  • Bowel perforation
  • Sepsis
  • Fistula formation
  • Radiation associated malignancies

Deterrence and Patient Education

Patients should be educated that eating foods that are high in fiber can soften stools naturally and improve some symptoms. The use of fiber supplements, including psyllium, can help improve symptoms. Patients should also attempt to avoid caffeine, smoking, complex sugars, and alcohol, as these can worsen diarrhea and lead to worsening pain and bleeding. Patients should also be educated that if the bleeding is excessive or they experience symptoms of dizziness and weakness, they should seek immediate medical attention.

Enhancing Healthcare Team Outcomes

Individualized treatment plans are likely required depending on the context of the patient, and discussion with at least one colleague or in an interprofessional team setting regarding the management is recommended. Collaboration and shared decision making and communication are key elements for a good outcome. The interprofessional care provided to the patient must use an integrated care pathway combined with an evidence-based approach to planning and evaluation of all joint activities. The earlier signs and symptoms of a complication are identified, the better the prognosis and outcome.

(Click Image to Enlarge)
Radiation Proctitis, moderate to severe, on colonoscopy
Radiation Proctitis, moderate to severe, on colonoscopy
Contributed by Tdvorak, Wikimedia Commons, (CC by 2.0) https://creativecommons.org/licenses/by/2.0/
Article Details

Article Author

David G. McKeown

Article Editor:

Scott Goldstein


1/27/2023 5:25:05 PM



Ballas LK,Elkin EB,Schrag D,Minsky BD,Bach PB, Radiation therapy facilities in the United States. International journal of radiation oncology, biology, physics. 2006 Nov 15;     [PubMed PMID: 17145535]


Otchy DP,Nelson H, Radiation injuries of the colon and rectum. The Surgical clinics of North America. 1993 Oct;     [PubMed PMID: 8378826]


Gilinsky NH,Burns DG,Barbezat GO,Levin W,Myers HS,Marks IN, The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients. The Quarterly journal of medicine. 1983 Winter;     [PubMed PMID: 6603628]


Palmer JA,Bush RS, Radiation injuries to the bowel associated with the treatment of carcinoma of the cervix. Surgery. 1976 Oct;     [PubMed PMID: 968730]


Hauer-Jensen M,Denham JW,Andreyev HJ, Radiation enteropathy--pathogenesis, treatment and prevention. Nature reviews. Gastroenterology & hepatology. 2014 Aug     [PubMed PMID: 24686268]


Villasanta U, Complications of radiotherapy for carcinoma of the uterine cervix. American journal of obstetrics and gynecology. 1972 Nov 15;     [PubMed PMID: 4633571]


Varma JS,Smith AN,Busuttil A, Correlation of clinical and manometric abnormalities of rectal function following chronic radiation injury. The British journal of surgery. 1985 Nov;     [PubMed PMID: 4063752]


Sharma B,Gupta M,Sharma R,Gupta A,Sharma N,Sharma M,Sharma V,Vats S,Gupta M,Seam RK, Four percent formalin application for the management of radiation proctitis in carcinoma cervix patients: An effective, safe, and economical practice. Journal of cancer research and therapeutics. 2019 Jan-Mar;     [PubMed PMID: 30880761]


Kapp KS,Stuecklschweiger GF,Kapp DS,Poschauko J,Pickel H,Hackl A, Carcinoma of the cervix: analysis of complications after primary external beam radiation and Ir-192 HDR brachytherapy. Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. 1997 Feb;     [PubMed PMID: 9106923]


Ali F,Hu KY, Evaluation and Management of Chronic Radiation Proctitis. Diseases of the colon and rectum. 2020 Mar;     [PubMed PMID: 32032142]


Mendelson RM,Nolan DJ, The radiological features of chronic radiation enteritis. Clinical radiology. 1985 Mar;     [PubMed PMID: 4064491]


Isenberg GA,Goldstein SD,Resnik AM, Formalin therapy for radiation proctitis. JAMA. 1994 Dec 21;     [PubMed PMID: 7990213]


Dziki Ł,Kujawski R,Mik M,Berut M,Dziki A,Trzciński R, Formalin therapy for hemorrhagic radiation proctitis. Pharmacological reports : PR. 2015 Oct;     [PubMed PMID: 26398382]


al-Sabbagh R,Sinicrope FA,Sellin JH,Shen Y,Roubein L, Evaluation of short-chain fatty acid enemas: treatment of radiation proctitis. The American journal of gastroenterology. 1996 Sep;     [PubMed PMID: 8792704]


Paquette IM,Vogel JD,Abbas MA,Feingold DL,Steele SR, The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Chronic Radiation Proctitis. Diseases of the colon and rectum. 2018 Oct;     [PubMed PMID: 30192320]


McElvanna K,Wilson A,Irwin T, Sucralfate paste enema: a new method of topical treatment for haemorrhagic radiation proctitis. Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland. 2014 Apr;     [PubMed PMID: 24299100]


Oscarsson N,Arnell P,Lodding P,Ricksten SE,Seeman-Lodding H, Hyperbaric oxygen treatment in radiation-induced cystitis and proctitis: a prospective cohort study on patient-perceived quality of recovery. International journal of radiation oncology, biology, physics. 2013 Nov 15;     [PubMed PMID: 24035333]


Hoggan BL,Cameron AL, Systematic review of hyperbaric oxygen therapy for the treatment of non-neurological soft tissue radiation-related injuries. Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer. 2014 Jun;     [PubMed PMID: 24794980]


Swan MP,Moore GT,Sievert W,Devonshire DA, Efficacy and safety of single-session argon plasma coagulation in the management of chronic radiation proctitis. Gastrointestinal endoscopy. 2010 Jul;     [PubMed PMID: 20493484]


Jao SW,Beart RW Jr,Gunderson LL, Surgical treatment of radiation injuries of the colon and rectum. American journal of surgery. 1986 Feb     [PubMed PMID: 3946764]


Pricolo VE,Shellito PC, Surgery for radiation injury to the large intestine. Variables influencing outcome. Diseases of the colon and rectum. 1994 Jul;     [PubMed PMID: 8026234]


Lev EL,Eller LS,Gejerman G,Lane P,Owen SV,White M,Nganga N, Quality of life of men treated with brachytherapies for prostate cancer. Health and quality of life outcomes. 2004 Jun 15;     [PubMed PMID: 15198803]


Liauw SL,Sylvester JE,Morris CG,Blasko JC,Grimm PD, Second malignancies after prostate brachytherapy: incidence of bladder and colorectal cancers in patients with 15 years of potential follow-up. International journal of radiation oncology, biology, physics. 2006 Nov 1;     [PubMed PMID: 16887293]