Late Effects of Treatment for Childhood Cancer (PDQ®): Treatment - Health Professional Information [NCI] - Late Effects of the Digestive System
Table 4. Oral/Dental Late Effects continued...
Radiation and specific chemotherapeutic agents may produce gastrointestinal (GI) or hepatic toxicity that is acute and transient in the majority of patients, but rarely may be delayed and persistent. Late radiation injury to the digestive tract is attributable to vascular injury. Necrosis, ulceration, stenosis, or perforation can occur and are characterized by malabsorption, pain, and recurrent episodes of bowel obstruction, as well as perforation and infection.[19,20,21] In general, fractionated doses of 20 Gy to 30 Gy can be delivered to the small bowel without significant long-term morbidity. Doses greater than 40 Gy cause bowel obstruction or chronic enterocolitis. Sensitizing chemotherapeutic agents such as dactinomycin or anthracyclines can increase this risk.
A limited number of reports describe GI complications in pediatric patients with genitourinary solid tumors treated with radiation.[23,24,25,26,27] One study comprehensively evaluated intestinal symptoms in 44 children with cancer who underwent whole-abdominal (10 Gy to 40 Gy) and involved-field (25 Gy to 40 Gy) radiation and received additional interventions predisposing them to GI tract complications including abdominal laparotomy in 43 (98%) and chemotherapy in 25 (57%) patients. Late small bowel obstruction was observed in 36% of patients surviving 19 months to 7 years, which was uniformly preceded by small bowel toxicity during therapy. Reports from the Intergroup Rhabdomyosarcoma Study evaluating GI toxicity in long-term survivors of genitourinary rhabdomyosarcoma infrequently observed abnormalities of the irradiated bowel.[24,25,27] Radiation-related complications occurred in approximately 10% of long-term survivors of paratesticular and bladder/prostate rhabdomyosarcoma and included intraperitoneal adhesions with bowel obstruction, chronic diarrhea, and stricture or enteric fistula formation.[24,27] Children irradiated at lower doses for Wilms tumor also uncommonly develop chronic GI toxicity. Several studies have reported cases of small bowel obstruction following abdominal surgery, but the role of radiation appears to be less important as operative findings of enteritis have not consistently been observed.[26,28] Among 5-year childhood cancer survivors participating in the Childhood Cancer Survivor Study (CCSS), the cumulative incidence of self-reported GI conditions was 37.6% at 20 years (25.8% for upper GI complications and 15.5% for lower GI complications) from cancer diagnosis representing an almost twofold excess risk of upper GI (relative risk [RR] = 1.8; 95% confidence interval [CI], 1.6–2.0) and lower GI (RR = 1.9; 95% CI, 1.7–2.2) complications compared with sibling controls. Factors predicting higher risk of specific GI complications include older age at diagnosis, intensified therapy (anthracyclines for upper GI complications and alkylating agents for lower GI complications), abdominal radiation, and abdominal surgery.
Table 5. Digestive Tract Late Effects
|Predisposing Therapy||Gastrointestinal Effects||Health Screening/Interventions|
|GVHD = graft-versus-host disease; KUB = kidneys, ureter, bladder (plain abdominal radiograph).|
|Radiation impacting esophagus; hematopoietic cell transplantation with any history of chronic GVHD||Esophageal stricture||History: dysphagia, heart burn|
|Esophageal dilation, antireflux surgery|
|Radiation impacting bowel||Chronic enterocolitis; fistula; strictures||History: nausea, vomiting, abdominal pain, diarrhea|
|Serum protein and albumin levels yearly in patients with chronic diarrhea or fistula|
|Surgical and/or gastroenterology consultation for symptomatic patients|
|Radiation impacting bowel; laparotomy||Bowel obstruction||History: abdominal pain, distention, vomiting, constipation|
|Exam: tenderness, abdominal guarding, distension (acute episode)|
|Obtain KUB in patients with clinical symptoms of obstruction|
|Surgical consultation in patients unresponsive to medical management|
|Pelvic surgery; cystectomy||Fecal incontinence||History: chronic constipation, fecal soiling|