You are in: eMedicine Specialties > Urology > Infections and Related Inflammatory Conditions Radiation CystitisArticle Last Updated: Feb 7, 2008AUTHOR AND EDITOR INFORMATIONAuthor: Nicolas A Muruve, MD, FRCSC, FACS, Associate Staff, Department of Urology, Cleveland Clinic Florida Nicolas A Muruve is a member of the following medical societies: American College of Surgeons, American Society of Transplant Surgeons, American Urological Association, and Royal College of Physicians and Surgeons of Canada Editors: Michael Grasso, MD, Chairman, Department of Urology, Saint Vincent's Medical Center; Professor and Vice Chairman, Department of Urology, New York Medical College; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Dan Theodorescu, MD, PhD, Paul Mellon Professor of Urologic Oncology, Department of Urology, University of Virginia Health Sciences Center; J Stuart Wolf, Jr, MD, FACS, David A Bloom Professor of Urology, Director, Division of Minimally Invasive Urology, Department of Urology, University of Michigan Medical Center; Stephen W Leslie, MD, FACS, Founder and Medical Director of the Lorain Kidney Stone Research Center, Clinical Assistant Professor, Department of Urology, Medical College of Ohio Author and Editor Disclosure Synonyms and related keywords: radiation cystitis, postradiation cystitis, radiation injury to the bladder, irritative voiding symptoms, asymptomatic hematuria, gross hematuria, contracted nonfunctional bladder, persistent incontinence, fistula formation, necrosis, hemorrhagic cystitis, vesical fistula, bladder neck contracture, neoplasia, contracted bladder, radiation morbidity, radiosensitivity, radiation neuritis, postradiation fibrosis, telangiectasia, diffuse erythema, prominent submucosal vascularity, mucosal edema, dysuria, prostate cancer, bladder cancer, colon cancer, rectal cancer, colorectal cancer INTRODUCTIONTumors of the pelvic organs (ie, prostate, bladder, colon, rectum) are common in men, comprising 45% of expected new cancer diagnoses for the year 2000. In women, cancer of the uterus, ovary, bladder, rectum, and vagina/vulva were expected to make up 23% of new cancer diagnoses in 2001. Radiation therapy is an important management tool for the treatment of these malignancies, creating significant potential for the development of radiation injury to the bladder. History of the ProcedureRadiation morbidity is due to incidental treatment of normal organs. Efforts to reduce the complications of radiation have led to improvements in delivery mechanisms of radiation to the target organ. Wide-field treatment was the standard of care for years, but it is associated with high morbidity. Cobalt therapy had high complication rates because of its low energy and resulting higher doses to healthy structures near the target. This was required to achieve an adequate dose to the tumor. Newer techniques and energy sources focus therapy on the target, minimizing collateral radiation to healthy structures. These techniques and energy sources include conformal beam therapy, CT- or ultrasound-guided brachytherapy, diversity of energies presently available (higher energies produce better tissue penetration, resulting in smaller doses to surrounding normal tissues), and more beams used (allows lower dose per beam, thus reducing the maximum dose to normal structures beyond the target tissues). ProblemRadiation therapy can be used as primary, adjuvant, or palliative treatment and often complements medical or surgical therapy for malignancies. Ideally, radiate only the tumor and exclude nontarget organs. Conformal beam therapy and brachytherapy attempt to do this. However, incidental irradiation of nearby tissues is unavoidable either because of invasion of surrounding organs by tumors or because of proximity of cancers to neighboring pelvic structures. Radiation cystitis is one complication of radiation therapy to pelvic tumors and manifests primarily as an alteration of the voiding pattern. The urinary bladder can be irradiated intentionally for the treatment of bladder cancer or incidentally for the treatment of other pelvic malignancies. The sequelae of radiation injury to the bladder can range from minor temporary irritative voiding symptoms and asymptomatic hematuria to more severe complications such as gross hematuria, contracted nonfunctional bladder, persistent incontinence, fistula formation, necrosis, and death. This article reviews the process of radiation injury and discusses the current standard for treatment of this condition. FrequencyThe reported frequency of radiation cystitis varies. This is because of difficulties in data collection (usually performed as a questionnaire), differences in dosimetry and field size used, and the fact that various tumors are treated with different fields and include varying amounts of bladder exposure. Frequency of radiation cystitis (>1 y posttreatment) based on common tumor sites (any symptom) is as follows:
Intensity-modulated radiotherapy (IMRT) has recently been shown to deliver higher doses to the target area while minimizing complications. Increasingly used for the treatment of prostate cancer, doses of 81 Gy have been delivered. The complication rate is lower compared with 3-dimensional conformal therapy, although not all studies show a significant difference.
After treatment for prostate cancer, rectal complications are much lower with conformal beam therapy than with 4-box small-field therapy (19% vs 32% grade 2 toxicity); however, the incidence of bladder complications is unchanged, probably because of the proximity of the bladder neck and unavoidable exposure to the urethra. IMRT has also demonstrated a significant improvement in rectal complications compared with 3-dimensional conformal radiation therapy. Fewer grade 2 bladder complications occur with IMRT, but the rate of grade 3 complications is similar with both modalities. After treatment for bladder cancer, acute symptoms (ie, those observed during treatment and lasting less than 1 year) are usually self-limiting and occur in 50-80% of patients for all tumor types. EtiologyRate of long-term complications depends on the following 3 major factors:
PathophysiologyTherapeutic radiation may be delivered via various external sources. It may be applied directly to the tumor, such as in interstitial or intracavitary therapy (brachytherapy), or it can be delivered by external beam therapy. Injury within radiated tissue results from the energy transferred by ionizing radiation to other molecules. Radiation interacts with intracellular water and produces free radicals that interfere with DNA synthesis, resulting in cell death. Cells that divide rapidly are most susceptible to radiation injury. Peak radiosensitivity to radiation is at the M and G2 phase of the cell reproductive cycle. Radiation may also directly cause rapid cell death from mitotic arrest, point mutations in DNA, and cell membrane damage. Concomitant use of chemotherapeutic agents may work synergistically to increase the risk of developing bladder injury from radiation. Radiation can also cause vascular changes. Subendothelial proliferation, edema, and medial thickening may progressively deplete the blood supply to the irradiated tissue. Collagen deposition may also cause severe scarring and further blood-vessel obliteration, resulting in tissue hypoxia and necrosis. The fibrotic barriers left behind can also impair revascularization. These events lead to mucosal ischemia and epithelial damage. This, in turn, may cause further submucosal fibrosis as the subepithelial tissues become exposed to the caustic effects of urine. This may manifest as pain in the clinical setting resulting from any of the above-mentioned mechanisms. Ulcer formation, radiation neuritis, and postradiation fibrosis may cause the clinical findings of pain and discomfort. Pathologic findings in radiated bladders include early and late findings.
Physiologically, these changes may produce clinical symptoms because of (1) ischemia and fibrosis leading to loss of bladder muscle fibers and thus to dysfunctional voiding and (2) denervation supersensitivity from ischemia causing abnormal neural stimulation of bladder. ClinicalIn 1983, radiation complications were graded on a scale derived by the RTOG. They are graded as follows:
In general, symptoms from radiation cystitis can be grouped into acute and late phases.
INDICATIONSIndications for treatment depend on the degree of symptoms present and the patient's sense of need to be treated. Grade 1 and 2 symptoms need treatment only if the patient is bothered by the symptoms. These can be managed medically. Observation is acceptable. Management of grade 3 and higher clinical presentations depends on the type of symptom. Voiding dysfunction can be managed medically if the patient desires (see Treatment). Urodynamics may be required if a patient presents with more complicated symptoms. Most symptoms can be evaluated by a thorough history and physical examination. Gross hematuria is an indication to evaluate volume status, coagulation status, and the need for RBC transfusion. Cystoscopy and renal imaging are also indicated to rule out other possible causes of genitourinary (GU) bleeding. Fistula formation usually requires surgical intervention. Contracted bladder and incontinence require evaluation to determine the degree of disability, bladder compromise, and potential need for surgery. RELEVANT ANATOMY
CONTRAINDICATIONSSurgery is reserved for the management of severe complications that do not respond to medical management. WORKUPLab Studies
Imaging Studies
Other Tests
Diagnostic Procedures
TREATMENTMedical therapyTherapy is primarily aimed at relief of symptoms. The exception is hyperbaric oxygen (HBO) therapy. Treatment with HBO can potentially reverse the changes caused by radiation. HBO therapy stimulates angiogenesis, which reverses the vascular changes induced by ionizing radiation. Preservation of bladder function and the noninvasive nature of treatment (30 sessions total) favor its use. Some reports claim 70% response with HBO. However, if significant fibrosis and ischemia have already occurred, HBO therapy does not reverse the changes and only prevents further injury. Symptomatic frequency and urgency are best treated with anticholinergic agents. Once all other causes of dysuria have been ruled out, phenazopyridine hydrochloride can be used to provide symptomatic relief. Hemorrhagic cystitis is a more serious complication of radiation cystitis. Once all clots have been evacuated and adequate drainage achieved, medical options to control the bleeding include continuous bladder irrigation alone, a 1% alum bladder installation, a 1-10% formalin bladder installation, aminocaproic acid (Amicar) bladder installation, sodium pentosanpolysulphate, HBO therapy, and oral estrogens. Prophylaxis against the development of radiation cystitis has been reported with the use of the antioxidant orgotein prior to receiving radiation. Dimethyl sulfoxide (DMSO) has also been described to have a radioprotective effect. However, few studies have evaluated its use in human bladders. The concept of using antioxidant therapy involves the theory that healthy tissues are damaged by free radicals produced within the target cell and then released into the extracellular space. The free radical is then allowed to travel to normal cells, where it then causes damage and clinically produces toxicity. Free-radical scavengers normally exist intracellularly and thus are not found in the extracellular space. By administering exogenous free radical scavengers, the intent is to decrease collateral damage to cells by picking up the extracellular free radicals. Note that these agents may also prevent collateral cell damage within tumors themselves. This could potentially decrease the effectiveness of anticancer therapy. Although reports exist of decreased toxicity with these agents, few report on overall disease control with antioxidant therapy compared to controls. One study looking at antioxidant therapy for oral tumors does show decreased toxicity with comparable tumor control rates.1 However, the study was small and involved a multimodality therapy, which may have contributed to their good results. Antioxidants require further study before they are put into widespread use. Reported responses to treatments are as follows: Adult Dose - Administer as 100% oxygen at 2-2.5 atm; each lasts from 90-120 min administered 5 d/wk for a total of 40-60 sessions Contraindications - Viral infection, absolute contraindication (can cause widespread viremia); partial pressure of carbon dioxide (PCO2) >60 mm Hg and pneumothorax, relative contraindications; history of ear surgery with inability to decompress the middle ear space; vitamin E deficiency; massive doses of ASA, vitamin C, or steroids (enhances likelihood of CNS oxygen toxicity); vitamin E deficiency, massive doses of ASA, vitamin C, or steroids (enhances likelihood of CNS oxygen toxicity) Interactions - None reported Pregnancy - A - Fetal risk not revealed in controlled studies in humans Precautions - Adverse effects are oxygen toxicity, which is rare (eg, seizures and alveolar membrane damage), confinement anxiety, ear pain, and digitalis toxicity (if taking drug); must be vented via a chest tube prior to pressurizing COPD; severe emphysematous changes can lead to spontaneous pneumothorax or congenital spherocytosis; HBO may increase RBC fragility; in pregnancy, use only in life-threatening situations; patients with epilepsy must be sedated because oxygen is a CNS stimulant; in fever of unknown origin, must find etiology before treating Drug Name - Sodium pentosanpolysulphate (Elmiron) - Response rate is 71-100%, and recurrence rate is 23%. Protects transitional epithelium by restoring the bladder glycosaminoglycan layer. Adult Dose - 100 mg Contraindications - Documented hypersensitivity Interactions - May increase effect of anticoagulants Pregnancy - B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals Precautions - Adverse effects, including diarrhea, nausea, alopecia (reversible upon discontinuation), headache, rash, dyspepsia, abdominal pain, liver function abnormalities, and dizziness, occurred at a frequency of 1-4% Drug Name - Formalin - A 37% solution of formaldehyde and water. Response rate is 52-89%, and recurrence rate is 20-25%. Mechanism of action is tissue fixative. Adult Dose - Local: 5% formalin pledgets are placed endoscopically on bleeding points for 15 min, then removed Bladder irrigation: 1-10% solution (4% preferred); manually fill bladder to capacity under gravity (catheter <15 cm above symphysis pubis); contact time ranges from 14 min for 10% solution to 23 min for 5% solution; this is a painful procedure and requires a general anesthetic Contraindications - Vesicoureteric reflux and bladder rupture or leak (use with caution in a patient with a recent bladder biopsy) Interactions - None reported Pregnancy - C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus Precautions - Preprocedure cystography to rule out reflux reduces the incidence of complications, which include pain, vesicoureteric reflux, fever, tachycardia, uremia and renal insufficiency, hydronephrosis, voiding dysfunction, fistula, papillary necrosis, and decreased bladder capacity Drug Name - Alum - Response rate is 50-80%, and the recurrence rate is 10%. Alum causes protein precipitation in the interstitial spaces and cell membranes, causing contraction of extracellular matrix and tamponade of bleeding vessels. Exposed capillary epithelium is also sclerosed. Adult Dose - 1% solution prepared by mixing 50 g of potassium aluminum sulfate in 5 L of distilled water; run intravesically at a rate of 3-5 mL/min and increase to a maximum of 10 mL/min if returns are not clear; continue for 6 h after bleeding stops Contraindications - Renal failure (aluminum is excreted by the kidneys, and patients with renal failure are at risk for development of aluminum toxicity) Interactions - None reported Pregnancy - C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus Precautions - Complications are increased PT, aluminum toxicity (eg, encephalopathy, dementia, speech disorders, osteomalacia, aplastic bone disease [chronic exposure associated with painful spontaneous fractures, hypercalcemia, and tumorous calcinosis]), proximal myopathy, increased risk of infection, increased left ventricular mass and decreased myocardial function, microcytic anemia with very high levels, and sudden death Drug Name - Aminocaproic acid (Amicar) - Response rate is 91%, and recurrences are not reported. Antifibrinolytic agent that inhibits plasminogen activation, thus decreasing plasmin. Adult Dose - 200 mg of aminocaproic acid in 1 L of isotonic sodium chloride solution; run intravesically according to severity of bleeding and continue for 24 h after bleeding stops Contraindications - Active intravascular clotting process or DIC Interactions - Coadministration with estrogens may cause increase in clotting factors, leading to a hypercoagulable state Pregnancy - C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus Precautions - When administered intravesically, systemic complications are reduced; these include thrombosis, obstruction of ureters with clot, hypotension, cardiac arrhythmias, and rhabdomyolysis Drug Name - Conjugated estrogens (Premarin) - Response rate is 100%, and recurrence rate is 20% (1 report of 5 patients only). Mechanism of action is unknown. In patients with renal failure, estrogen has been reported to correct prolonged bleeding time. However, in radiation cystitis complications, bleeding time is usually normal. Adult Dose - 5 mg/d Contraindications - Known or suspected pregnancy; undiagnosed abnormal genital bleeding; known or suggested breast cancer; known or suggested estrogen-dependent neoplasia; active thrombophlebitis or thromboembolic disorders; documented hypersensitivity Interactions - May reduce hypoprothrombinemic effect of anticoagulants; coadministration of barbiturates, rifampin, and other agents that induce hepatic microsomal enzymes may reduce estrogen levels; pharmacologic and toxicologic effects of corticosteroids may occur as a result of estrogen-induced inactivation of hepatic P450 enzyme; loss of seizure control has been noted when administered concurrently with hydantoins Pregnancy - X - Contraindicated; benefit does not outweigh risk Precautions - Complications are thromboembolism, breast and uterine cancer (prolonged exposure), cholelithiasis, pancreatitis, nausea, vomiting, abdominal cramps, bloating, cholestatic jaundice, erythema multiforme, erythema nodosum, hemorrhagic eruption, alopecia, hirsutism, headache, migraine, dizziness, mental depression, chorea, aggravation of porphyria, edema, and changes in libido Drug Name - Pentoxifylline (Trental) - Pain relief from radiation fibrosis has also been reported with pentoxifylline. Pentoxifylline and its metabolites improve the flow properties of blood by decreasing its viscosity. This increases blood flow to the affected microcirculation and enhances tissue oxygenation. The precise mode of action of pentoxifylline and the sequence of events leading to clinical improvement remain undefined. Adult Dose - 400 mg Contraindications - Recent cerebral and/or retinal hemorrhage; previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine Interactions - Coadministration with cimetidine or theophylline, increases effect/toxic potential; pentoxifylline increases effect of antihypertensives Pregnancy - C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus Precautions - Adverse effects are chest pain, arrhythmias, drowsiness, flushing, dizziness, irritability, tremor, convulsions, dizziness, headache, nausea or vomiting, and abdominal pain If the symptoms of radiation cystitis are not severe but significant enough for a patient to seek help, sodium pentosanpolysulphate with or without pentoxifylline for pain is a reasonable first step. If symptoms become more severe or oral therapy is not satisfactory, HBO therapy, based on the available literature, appears to have the most consistent results. If bleeding is severe, bladder irrigation may be started either alone or in conjunction with hyperbaric therapy. Start continuous bladder irrigation alone first. If this is not successful, try the next least toxic agent. In order, these agents are alum, aminocaproic acid, and formalin. Surgical therapySurgery is reserved for the management of severe complications that do not respond to medical management. Indications for surgery include ongoing gross hematuria that does not respond to bladder irrigations or that require numerous transfusions, small contracted bladder with incontinence or severe frequency, and specific complications of radiation (eg, fistulas, hydronephrosis, strictures). Surgical options for hemorrhagic cystitis include cystoscopy and fulguration, percutaneous nephrostomy tube insertions, internal iliac artery embolization, surgical diversion, and cystectomy. Surgical options for small-volume bladder include bladder augmentation, urinary diversion, and cystectomy. Follow-upFollow-up care for radiation cystitis is generally supportive. Symptoms can be recurrent or even persistent, as in the case of dysfunctional voiding. Because symptomatic manifestations of radiation cystitis can occur many years after primary radiation therapy, regular clinical follow-up care and good communication with patients are essential. COMPLICATIONSComplications of radiation cystitis include hemorrhagic cystitis (3-5%), vesical fistula (2%), and bladder neck contracture (3-5%). Neoplasia and contracted bladder can also occur but are rare. OUTCOME AND PROGNOSISSymptoms of radiation cystitis are chronic in nature. If therapy is required for symptomatic disease, it tends to be permanent. Acute symptoms of radiation injury to the bladder are self-limiting and generally respond to symptomatic therapy such as anticholinergic medications and analgesics. Severe complications of radiation injuries are difficult to manage because they tend to be recurrent and occasionally refractory to therapy. Few follow-up studies and the small number of patients reported in these studies limit proper interpretation of treatment outcome. The available follow-up studies performed with various treatment regimens demonstrate that, although all have some effectiveness, no single modality is superior. They also show the recurrent nature of radiation complications of the bladder. FUTURE AND CONTROVERSIESThe use of endoscopic injection sclerotherapy has been reported with good results in a limited number of patients with intractable hemorrhagic cystitis. This treatment involves the injection of a sclerosing agent (eg, 1% ethoxysclerol) into the bleeding areas to control the severe hematuria in patients with otherwise intractable bleeding not responding to simpler methods. Further studies are necessary to determine the exact role of this novel type of therapy in selected patients with radiation cystitis. FURTHER READINGFor additional informations, see Medscape’s Bladder Cancer Resource Center, Prostate Cancer Resource Center, and Colorectal Cancer Resource Center. MULTIMEDIA
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