MANAGEMENT OF RADIATION PROCTITIS

Radiotherapy is frequently used in the treatment of cancer inc ombination with other treatments.

In men the two most prevalent cancers requiring radiotherapy are cancer of the bladder and cancer of the prostate.

“As after radical surgery where complications may occur, radiotherapy is not without problems,” reports Dr Chapuis.

Rectal bleeding is a known treatment complication of prostate cancer. Three different terms are used to describe this condition. They are:

•Actinic proctitis

•Radiation proctitis

•Chronic radiation-induced rectal bleeding (CRRB).


Rectal bleeding may complicate treatment in 5 to 10 percent of patients. Rectal bleeding is caused by radiation thickening of the walls of small arteries supplying the rectum, and so by narrowing them to restrict the blood flow to the rectal wall.

To compensate for this, new thread-like capillaries grow in profusion very close to the internal surface of the rectum. It is the fragility of these capillaries that causes the bleeding. As this does not involve true inflammation, “proctitis” is an inappropriate term.

Professor Chapuis prefers the third description: chronic radiation-induced rectal bleeding(CRRB). The rectal bleeding may not start until some 12 months to three years after treatment. Because bleeding is a known side effectof radiation therapy for prostate cancer, and rarely may be life-threatening, patients should be informed of this risk and consent to such treatment.

Rectal symptoms can fall into two broad categories which are partly dose-related: acute and chronic.


Acute:

Symptoms include tenesmus (pain on passing stools), diarrhoea, urgency of defaecation and bleeding.

Chronic:

Symptoms include stricture (narrowing or restriction), fistula (abnormal passage), CRRB, varying degrees of incontinence, loss of compliance and storage capacity of the rectum.


Clinical features of CRRB include:

• It is classed as Grade III on a scale of seriousness from I to IV, ie quite serious. Around 50 percent of cases are late onset (ie, starting later than one year after treatment).

• From a situation with the patient not experiencing any problems, it may become chronic with progressively increasing bleeding resulting in iron deficiency anaemia which may require daily dosage of iron tablets.

• Fifteen to 20 years ago it quite often led to transfusion-dependent anaemia, necessitating frequent blood transfusions, but this is now very unusual as a result of much improved radiotherapy techniques. It is important for prostate cancer patients to recognise that some degree of “collateral” damage will inevitably occur to the rectum due to the radiation treatment.

Late development of bleeding will be experienced by a small proportion of these patients, but this is nowhere near as common or severe a problem as in the past. A critical decision is whether the benefit of the radiation treatment of the cancer outweighs the risks of rectal bleeding or other complications as a result of that treatment.


The factors which affect the risk include:

• The total dose of the radiation

• The fractionation of the dose ie, how it is delivered

• The build of patient, as obese people are more susceptible

• Diabetes

• Hypertension

• Previous abdominal or pelvic surgery (adhesions)

• Chronic diverticular disease of the proximal bowel

• Bleeding may be exacerbated if taking drugs such as Asprin,Warfarin or Plavix Possibly because of their genetic make-up, some men are inherently more sensitive to radiation.


Quality of life issues that may influence the decision whether to opt for/out of radiotherapy include:

• The alarm caused by unexpected bleeds

• The late onset (leading to several years of anxiety about whether bleeding will occur)

• The absence of identifiable risk factors in many cases pre-venting prediction of whether any particular patient will be affected

• Whether the patient has other conditions, such as diabetesor hypertension.


Additional issues include:

• The unpredictable nature of the bleeding which is socially inconvenient and can be acutely embarrassing

• The resulting anaemia is debilitating

• Poor response to treatment

• Simple treatments often pre-scribed (like steroid supposito-ries or enemas) are usually of little benefit

• The condition can last a longtime

• There is a (small) possibility of it progressing to Transfusion Dependent Anaemia.


Patients with CRRB should be thoroughly assessed, including their history and a physical examination, a blood test including a full blood count, iron studies and coagulation profile. Then a safe and thorough examination by colonoscopy of the large bowel enables the severity of the condition to be determined and identification of other sources of bleeding.

A cystoscopy and/or special small bowel X-ray are sometimes appropriate. Sometimes anorectal manometry is needed to test the strength of the sphincter muscle prior to treatment.

The patient may be asked to keep a record of bleeds by marking a calendar as treatment progresses. There are several options for treatment, which will be influenced by the location of the source of bleeding and the extent of the condition.


Minimally invasive therapy includes:

• Electrocautery

• Argon Plasma Coagulation Therapy (APC)

• Endoscopic laser

• Formalin (formaldehyde) dressings applied under a general anaesthetic

• Hyperbaric oxygenation with multiple treatment episodes required.


In the case of APC or endoscopic laser, each potential bleeding pointneeds to be separately treated. The procedure may require several visits, spaced a few weeks apart, to allow the lining of the rectum to recover. The procedure may be undertaken under conscious sedation or general anaesthesia.

The use of formalin began in the1960s. It was found that the formalin destroyed the superficial lining (which then separated off) thus causing the bleeding to stop and allowing the new lining to regrow without blood vessels.

However, the appropriate concentration for the formalin was uncertain, and the approach was abandoned until more recently, when a particular low concentration has been found to be both effective and safe.

A blood count is taken before and after treatment. The patient undergoes a general anaesthetic and is prepared by applying plastic skin dressings applied to the skin surrounding the anal passage. A speculum is inserted and dressings containing formalin are packed into the rectum through it and left for five to ten minutes before being removed. This is repeated until bleeding ceases.


Up to 20% of patients treated with the formalin method experience complications, like:

• Mucus incontinence either from treatment or from the initial radiotherapy

• Some patients may need to wear a pad

• Acute prostatitis (very rare)

• Narrowing of the rectum (veryrare)

• Ischaemic ulcer.

This is pre-vented by taking care to cover exterior of anus with a plastic skin during treatment. Use of either the laser or the formalin method, or both together, results in 75 – 80% success.

However, treatment and follow up may be necessary for up to 12 months. For otherwise intractable cases, several surgical options exist.

Our sincere thanks to Dr Chapuis for his carefully structured presentation and clear explanations, and for fielding wide ranging questions. Summarised by Mark Tweed-dale and Pam Sandoe. Edited and approved by Dr Chapuis; 'The Management of Radiation Proctitis'.