Medical management of radiation enteritis--an algorithmic guide

Adjuvant Radiotherapy of the Pelvis with or without Reduced Glutathione: A Randomized Trial in Patients Operated on for Endometrial Cancer

A randomized pilot trial was performed to evaluate the feasibility of administration of glutathione (GSH, 1200 mg, i.v.) as a protector in preventing diarrhea in patients operated on for endometrial cancer and submitted to adjuvant radiotherapy of the pelvis. Diarrhea occurred In 52% of patients In the untreated control group and only in 28% of patients In the GSH-treated group. Our preliminary data indicate that GSH administered before radiotherapy reduced the occurrence of diarrhea from oxidative damage to the intestinal mucosa. A large-scale phase III study is required to obtain definitive conclusions on the protective potential of GSH.

Radiation damage to the gastrointestinal tract: mechanisms, diagnosis, and management

PURPOSE OF REVIEW

To summarize current knowledge about gastrointestinal radiation toxicity, with emphasis on mechanisms and clinical diagnosis and management.

RECENT FINDINGS

While there has been only modest change in cancer incidence and cancer mortality rates during the past 30 years, the number of cancer survivors has more than doubled. Moreover, the recognition of uncomplicated cancer cure as the ultimate goal in oncology has intensified efforts to prevent, diagnose, and manage side effects of radiation therapy. These efforts have been facilitated by recent insight into the underlying pathophysiology.

SUMMARY

The risk of injury to the intestine is dose limiting during abdominal and pelvic radiation therapy. Delayed bowel toxicity is difficult to manage and adversely impacts the quality of life of cancer survivors. More than 200,000 patients per year receive abdominal or pelvic radiation therapy, and the estimated number of cancer survivors with postradiation intestinal dysfunction is 1.5-2 million. Worthwhile progress towards reducing toxicity of radiation therapy has been made by dose-sculpting treatment techniques. Approaches derived from an improved understanding of the pathophysiology of bowel injury, however, will result in further advances. This article discusses the mechanisms of radiation-induced bowel toxicity and reviews current principles in diagnosis and management.

Gastrointestinal symptoms after pelvic radiotherapy: a new understanding to improve management of symptomatic patients

Gastrointestinal symptoms after pelvic radiotherapy, which affect quality of life, are substantially more common than generally recognised and are frequently poorly managed. These symptoms develop because radiation can induce change in one or more specific physiological functions in widely separated parts of the gastrointestinal tract that lie in the path of the radiotherapy beam. Radiation-induced changes are not confined by normal anatomical boundaries. Furthermore, pre-existing subclinical disease might be destabilised because of minor gastrointestinal changes induced by radiotherapy. New diseases might manifest after radiotherapy and be confused with symptoms induced by radiotherapy. Different functional deficits might cause the same symptoms. Many patients have more than one cause for their symptoms, which sometimes need very different treatments. Simple diagnostic tests that are used in other contexts, if applied appropriately to patients with new gastrointestinal symptoms after radiotherapy, can identify the underlying causes of new-onset symptoms. Starting treatment without knowing the cause of the symptom is commonly ineffective because prediction of the combination of treatments needed is difficult. Evidence suggests that many patients have unusual but highly treatable malfunctions of gastrointestinal physiology, which if correctly diagnosed may enable a patient with difficult symptoms to be helped.

Gastrointestinal problems after pelvic radiotherapy: the past, the present and the future

Up to 300,000 patients per year undergo pelvic radiotherapy worldwide. Nine out of 10 will develop a permanent change in their bowel habit as a result. Five out of 10 of all patients will say that this change in their bowel habit affects quality of life and two to three out of 10 will say that this effect on quality of life is moderate or severe. Between one in 10 and one in 20 patients will develop very serious complications within the first 10 years after treatment. This number will increase to two out of 10 by 20 years from the end of treatment. Although research carried out into the basic molecular, cytokine and physiological changes underlying radiation-induced bowel symptoms and the optimal treatment that should be provided to symptomatic patients is scant, it does seem probable that a significant proportion of these patients can be cured or improved by specialist gastroenterological intervention. However, most patients never get referred to a specialist gastroenterologist and research into late radiation bowel damage has not been considered a priority. With the advent of more effective cancer therapies leading to greater numbers of affected long-term survivors, much more emphasis is urgently required to provide better information to patients at the start and after treatment, developing techniques that might reduce the frequency of significant bowel toxicity and researching better ways of measuring and treating late-onset side-effects.

The clinical needs of patients with chronic gastrointestinal symptoms after pelvic radiotherapy

BACKGROUND

After radiotherapy for pelvic cancer, gastrointestinal symptoms affecting quality of life are common. How they affect daily living is unknown.

AIM

To investigate the day-to-day impact of gastrointestinal symptoms in patients after pelvic radiotherapy.

METHODS

New patients referred for gastroenterological evaluation of radiotherapy-induced symptoms were sent a questionnaire.

RESULTS

Over 15 months, 75 of 100 questionnaires were completed before the gastroenterology appointment by 45 men (median age 70) and 30 women (median age 57) treated for urological (n = 44), gynaecological (n = 27) and gastrointestinal (n = 4) cancers. Time since radiotherapy was 3 years (median) for women and 1.5 years (men). Women experienced 6 (median) symptoms whilst men experienced 4. Having someone listen to problems was often as important as treatment. Urgency, diarrhoea, pain, rectal bleeding, flatulence and bloating were particularly troublesome. 57% women and 33% men were 'very affected'. Symptoms rarely improved with time and in 33% had been present for more than 2 years. Gastrointestinal symptoms affected quality of life through change of routine (F 37%, M 22%), social limitation (F 17%, M 33%), physical limitations (F 33%, M 16%), emotional difficulties (F 47%, M 18%) and sexual problems (F 30%, M 51%).

CONCLUSIONS

Patients experience a high number of physical symptoms for long periods before referral. Clinicians must focus systematically on physical, emotional and psychosexual issues.

Gastrointestinal symptoms after pelvic radiotherapy: role for the gastroenterologist?

PURPOSE

To analyze the cause of GI symptoms after pelvic radiotherapy (RT) in a consecutive series of patients with symptoms beginning after RT. A striking lack of evidence is available concerning the optimal treatment for the 50% of patients who develop permanent changes in bowel habits affecting their quality of life after pelvic RT. As a result, in the UK, most such patients are never referred to a gastroenterologist.

METHODS AND MATERIALS

All diagnoses were prospectively recorded from a consecutive series of patients with symptoms that started after RT and who were referred during a 32-month period to a gastroenterology clinic. Patients either underwent direct access flexible sigmoidoscopy or were investigated in a standard manner by one gastroenterologist after first being seen in the clinic.

RESULTS

A total of 265 patients referred from 15 institutions were investigated. They included 90 women (median age, 61.5 years; range, 22-84 years) and 175 men (median age, 70 years; range, 31-85 years). RT had been completed a median of 3 years (range, 0.1-34 years) before the study in the women and 2 years (range, 0-21 years) before in the men. Of the 265 patients, 171 had primary urologic, 78 gynecologic, and 16 GI tumors. The GI symptoms included rectal bleeding in 171, urgency in 82, frequency in 80, tenesmus, discomfort, or pain in 79, fecal incontinence in 79, change in bowel habit in 42, weight loss in 19, vomiting without other obstructive symptoms in 18, steatorrhea in 7, nocturnal defecation in 8, obstructive symptoms in 4, and other in 24. After investigation, significant neoplasia was found in 12%. One-third of all diagnoses were unrelated to the previous RT. More than one-half of the patients had at least two diagnoses. Many of the abnormalities diagnosed were readily treatable. The symptoms were generally unhelpful in predicting the diagnosis, with the exception of pain, which was associated with neoplasia (p < 0.001).

CONCLUSION

The results of our study have shown that radiation enteritis is not a single disease entity. More than one-half of the patients had more than one GI diagnosis contributing to their symptoms. After pelvic RT, specific GI symptoms were not a reliable measure of the underlying diagnoses, and the evaluation of new GI symptoms is worthwhile. An algorithm for this purpose is proposed.

[D-xylose test of resorption as a method to determine radiation side effects in the small intestine]

BACKGROUND

The D-xylose test is the most important method to determine a disorder of carbohydrates resorption in proximal small intestine. The application is based on an impaired resorption due to pathological change of small intestine surface, leading to a decreased blood level or decreased excretion in urine.

PATIENTS AND METHOD

D-xylose test was applied in 91 patients before, shortly after, 1/2 and 1 year after radiotherapy. All patients received an abdominal radiotherapy. We determined the blood level of D-xylose by a capillary blood sample 1 hour after oral D-xylose administration.

RESULTS

A significant decrease of the mean blood level of D-xylose to 1.88 mmol/l was determined after radiotherapy in comparison with 2.17 mmol/l before radiotherapy. Half a year after radiotherapy the mean blood level of D-xylose returned to normal. Regarding a threshold value of D-xylose blood level of 1.70 mmol/l 29 patients (32%) showed a pathologically decreased D-xylose resorption after radiotherapy. Twenty out of the 29 patients already showed a normal resorption half a year after the determination of the resorption disorder, 5 patients after 1 year and 4 patients after 1 1/2 years. There was no correlation between the detection of a disorder of D-xylose resorption and of a loss of body weight. The acute clinical side effects seemed to be more marked in connection with a disorder of D-xylose resorption, but this correlation is not significant. Eleven or 14 of the 29 patients, respectively, with pathologically decreased D-xylose resorption only had complaints of lower or upper gastrointestinal tract, respectively, and 10 patients did not have abdominal complaints at all.

CONCLUSIONS

The D-xylose test is an important and simple method for determination of radiogen induced carbohydrate malabsorption in proximal small intestine. By means of it radiation side effects on small intestine can also be determined in patients who are otherwise free of complaints.

Late radiation injury of the small intestine. Clinical, pathophysiologic and radiobiologic aspects. A review

Transient symptoms due to injury of the intestinal mucosa occur in the majority of patients receiving radiation therapy for pelvic or intra-abdominal neoplasms. Late (chronic) radiation enteropathy, although less common, is a more serious condition, associated with high morbidity and mortality. The manifestations of late radiation enteropathy are primarily due to changes in compartments other than the mucosa, such as intestinal wall fibrosis and obliterating vascular sclerosis. As a result of recent clinical and experimental studies, considerable knowledge about the pathogenesis, dose-response relationship, and time-course of development of late radiation enteropathy has been obtained. Also, the advent of new animal models has facilitated studies of time-dose-fractionation relationships in the intestine. The present paper summarizes clinical, pathophysiologic, and radiobiologic aspects pertinent to the development of chronic intestinal radiation injury.