<b>ABDOMEN & PELVIS</b> 

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In several series of patients treated by radiation, the <b>early gastrointestinal complication rate varied from approximately 10 to 20%. The late gastrointestinal complication arising varied from approximately 2 to 11%</b>. In one study, there was an 8.2% incidence of late complications developing in those patients who had experienced early complications, compared with a 3.0% incidence of late complications developing in patients without early complications. Thus, the risk of developing a late complication was greater by a factor of 2.7 in those patients developing an early one. However, of the patients developing late complications (75%) did not experience a severe acute one.

The median time for severe radiation late effects [adhesion, fistula, structure, perforation, colitis, or vascular occlusion] after radiotherapy was 18 months, as against 9 to 10 months for milder symptoms. Rectal bleeding is a factor with a significantly poorer prognosis.

The most consistently observed changes in Radiation Bowel Disease were in the arteries, arterioles and to a lesser extent the veins. The damaged blood vessels showed small clots, death of cells making up the blood vessel wall, and swelling and edema around the vessel wall. The blood vessels are a main site of injury in RBD and that the wall of the blood vessels is an initial target for radiation damage. <b>The effect of radiation was an on-going process; the percentage of small arteries with cell wall scarring increased with the time after radiotherapy</b>. [See Arteries]

<b>Vitamin B12 malabsorption after irradiation for gynecological tumours is common, and routine follow-up of patients should include a blood test for B12 levels.</b>

The effects of pelvic radiotherapy on 202 prostate cancer patients [men] were reported as a major alteration in bowel function in 11%, significant bladder symptoms in 4%, and loss of potency in 35%.

<b>Cause of Radiation Damage:</b> 

Dosage, timing, inflammation , poor nutrition, previous operations, and the presence of infection have all been implicated in causing or exacerbating late effects.

One study found that the only factors significantly related to late intestinal complications were the beam arrangement and, consequently, the treated volume. Detailed analysis showed that radiation sequelae developed in 12/106 (11.3%) patients treated with the two sagittal fields technique, while small bowel toxicity was observed in only 2/85 (2.3%) patients treated with the three--or four--fields technique. The difference is statistically significant (p < 0.05).

Pelvic radiation tissue toxicity increased significantly when the dose exceeds 45 Gy, with the incidence of marked bladder and rectal changes rising from 8% to 51% and from 24% to 48%, respectively [MR scans]. Similar dose-related changes are seen in other pelvic organs. In asymptomatic patients, minimal MR changes were seen in the bladder (47%) and in the rectum (33%). 

The incidence of bladder, rectal, & vaginal radiation damage differs for different irradiation methods and different fractionalization of dosages. Some factors that contribute to risk of complications due to late radiation damage of the small bowel are: hypoalbuminemia, more than one laparotomy prior to irradiation and a short interval (< 12 months) between irradiation and surgical intervention.

<b>Description of Damages and Treatment:</b>
 
Small bowel obstructions due to extensive matted small bowel adherent to the pelvic operative sites are frequent sequelae of radical hysterectomy, being more common if concomitant radiotherapy is given.

Radiation therapy of cancers in the pelvic region may lead to radiation <b>proctitis</b> [inflammation of the rectum]. Radiation injury to the rectal wall results in damage and obliteration of the blood vessels, causing death of local tissue and subsequent scarring. Patients with radiation proctitis may be minimally ill and heal spontaneously. However, symptoms of proctitis may persist, and the disease progress to chronic bleeding and/or stricture and fistula formation. Medical therapy is often unsuccessful, and surgery is eventually required. Because of numerous postoperative complications and no guarantee of success, surgery is often recommended as a last resort.

<b>Ureteral stricture</b> is a rare late complication of curative radiotherapy. During the first 5 years after treatment, tumor recurrence is the most common cause of ureteral stricture in patients treated with radiotherapy. However, radiation injury to the ureter, although rare [continuous actuarial risk increase of approximately 0.15% per year], may not become apparent for many years, necessitating continued vigilance. Radiation injury can also occur to the kidneys as well as the ureters.

Arterial occlusions[blockages] are a rare yet dramatic complication of radiotherapy for gynecologic cancer. Three patients underwent <b>amputation</b> of a lower extremity when they developed <b>chronic arterial insufficiency</b> after pelvic radiotherapy. The patients were irradiated at the ages of 28, 30, and 35 years. Two received neutron beam therapy and one received conventional photon beam therapy. All three had extensive late radiation morbidity to the bladder and rectum and had multiple prior surgeries. The amputations occurred at the ages of 48, 48, and 55 due to accelerated arteriosclerosis. Two patients died as a result of this complication. 

The differentiation of the variations in appearance which can be produced by radiotherapy damage from recurrent malignancy can be difficult.

<b>Surgical treatment of intestinal radiation injury.</b> 

Many cases require operative intervention. This usually consists of resection, the establishment of a bypass anastomosis [joining bowel in such a manner as to bypass the problem area] or enterostomy [creation of a stoma for bowel]. There is a high complication rate, and often a significant mortality, partly due to the poor general condition of the patient, and partly due to the radiation induced impairment in wound healing, which may lead to insufficiency of the anastomosis [join] and the development of fistulae [draining channels from one area to another].

The endoscopic spectrum of late radiation damage to the rectosigmoid colon included abnormalities of the mucosa with characteristic telangiectasis, luminal narrowing, superficial or deep solitary ulcers or more extensive diffuse ulceration and fistulae. Late radiation damage presented as stenoses , fistulas , perforations, rectal ulcers and hemorrhagic proctitis. Resection with end-to-end-anastomosis and bypass were the operations most frequently performed on the small bowel, whereas most colonic and rectal lesions were treated by colostomy alone. The postoperative course complications include fistulas, peritonitis, pulmonary embolism, and ulcer perforations. This series had a 10.7% death rate.

Another series of twenty-eight patients with late radiation damage presented with rectovaginal fistulas, hemorrhage from ulcerative proctitis, low rectal strictures, rectal ulcer and rectal carcinoma. Associated pathology in these patients included urinary fistulas, small bowel fistulas or stenoses and a variable degree of fibrosis of the pelvic cellular tissue. Treatment involved subtotal rectal resection with restoration of continuity by means of a perianal sleeve anastomosis between healthy colon and the rectal stump denuded of its mucosa. Technical success was achieved in 35 of the 37 patients, <b>with no mortality</b>. Where anastomosis was possible at a higher level, all 19 patients cured of fistula, ulcer, stenosis or hemorrhagic proctitis were fully continent at 1 year.

A review of 43 consecutive patients requiring operation for serious intestinal radiation injury was undertaken to elucidate the efficacy of surgical treatment. The overall operative mortality was 14%; morbidity, 47%; and the postoperative symptom-free period, 18 +/- 30 months. <b>Colostomy (N = 20) carried the lowest risk of mortality, 0%, as compared with resection (N = 17) and bypass procedure (N = 6), which were accompanied by the mortalities of 24% and 33%, respectively.</b> During the follow-up (3-13 years) 12 patients (28%) died of recurrent cancer and 9 patients (21%) of persistent radiation injury, which yielded an overall mortality of 65% after resection and 50% and 65% after bypass and colostomy procedures, respectively. Continuing radiation damage led to 15 late reoperations. Ten of these were performed after colostomy, four after resection, and one after bypass. <b>We conclude that colostomy cannot be regarded as a preferred operative method, because it does not prevent the progression of radiation injury and because it is, for this reason, associated with a higher late-complication rate.</b> A more radical surgery is recommended but with the limitation that the operative method must be adapted to the operative finding. 

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