Radiation-induced stenosis of the renal artery causing hypertension: case report

Hypertension in Wilms tumor

Wilms tumor (WT) represents over 90% of all pediatric kidney tumors. Children with WT often present acutely with hypertension which resolves in the short term after nephrectomy. However, WT survivors have increased long-term risk of hypertension, primarily due to decreased nephron mass after nephrectomy, with additional insults from possible exposure to abdominal radiation and nephrotoxic therapies. The diagnosis of hypertension may be improved by ambulatory blood pressure monitoring (ABPM), as several recent single-center studies have shown a substantial proportion of WT survivors with masked hypertension. Current gaps in knowledge include determining which WT patients may benefit from routine screening with ABPM, correlation of casual and ABPM parameters with cardiac abnormalities, and longitudinal assessment of cardiovascular and kidney parameters in relation to appropriate treatment of hypertension. This review aims to summarize the most recent literature on hypertension presentation and management at the time of WT diagnosis as well as the long-term hypertension risk and impact on kidney and cardiovascular outcomes in WT survivors.

Pharmacological Interventions for the Prevention and Treatment of Kidney Injury Induced by Radiotherapy: Molecular Mechanisms and Clinical Perspectives

More than half of cancer patients need radiotherapy during the course of their treatment. Despite the beneficial aspects, the destructive effects of radiation beams on normal tissues lead to oxidative stress, inflammation, and cell injury. Kidneys are affected during radiotherapy of abdominal malignancies. Radiation nephropathy eventually leads to the release of factors triggering systemic inflammation. Currently, there is no proven prophylactic or therapeutic intervention for the management of radiation-induced nephropathy. This article reviews the biomarkers involved in the pathophysiology of radiation-induced nephropathy and its underlying molecular mechanisms. The efficacy of compounds with potential radio-protective properties on amelioration of inflammation and oxidative stress is also discussed. By outlining the approaches for preventing and treating this critical side effect, we evaluate the potential treatment of radiation-induced nephropathy. Available preclinical and clinical studies on these compounds are also scrutinized.

Long-term renal function after treatment for unilateral, nonsyndromic Wilms tumor. A report from the St. Jude Lifetime Cohort Study

BACKGROUND

The impact of specific treatment modalities on long-term renal function and blood pressure among adult survivors of Wilms tumor (WT) has not been well documented.

METHODS

Among 40 WT survivors and 35 noncancer controls, we estimated the glomerular filtration rate (eGFR) using the Chronic Kidney Disease-Epidemiology (CKD-EPI) equations with and without cystatin C, obtained 24-hour ambulatory blood pressure readings, and, among survivors only, measured ^99m Tc diethylenetriamine pentaacetic acid (DTPA) plasma clearance. Survivors were treated with unilateral nephrectomy and nonnephrotoxic chemotherapy. Twenty received whole abdomen radiation therapy (WART) [median -16.5 Gray (Gy)], and 20 received no radiation therapy. Pairwise comparisons between survivors treated with and without WART, and each group to controls were performed using two-sample t tests.

RESULTS

Twenty-six (65%) WT survivors were female, and 33 (83%) were non-Hispanic white. GFR estimated with creatinine or creatinine + cystatin C was decreased among irradiated survivors compared with controls. No irradiated or unirradiated participant had an eGFR (creatinine + cystatin C) < 60 mL/min/1.73 m² . The prevalence of hypertension was significantly increased among unirradiated (25%) and irradiated survivors (35%) compared with controls (0%). Of the 24-hour ambulatory blood pressure monitoring parameters evaluated, only mean sleep period diastolic blood pressure load of those who received WART was significantly different from that of controls.

CONCLUSIONS

Chronic kidney disease was infrequent in long-term survivors of unilateral nonsyndromic WT, whether treated with WART or no radiation. The prevalence of hypertension was increased in both groups compared with controls, emphasizing the need for ongoing monitoring of renal and cardiovascular health.

[Late effects of radiations on the kidney]

Clinical radiation damage to the kidney are nowadays a rare event. Nevertheless, this organ is very sensitive to radiation and dose exceeding 15 Gy may induce severe and life threatening damage many years after the treatment. Prevention remains the best treatment through a precise localisation of the kidneys before any irradiation of the upper abdomen.

Outcomes of high-dose unilateral kidney irradiation in patients with gastric lymphoma

PURPOSE

To review the long-term clinical effects of unilateral kidney irradiation on overall renal function and blood pressure in patients with gastric lymphoma.

METHODS AND MATERIALS

In the study were 27 patients with Stage I or II gastric lymphoma who had undergone irradiation of at least 24 Gy to > or = 1/3 of the left kidney. They include 16 women and 11 men, aged 31 to 77, with a mean age of 57.6 years (median 56). Fifteen patients had Stage I and 12 had Stage II disease. In 13 patients the whole kidney had been irradiated, and 14 had had partial kidney irradiation, at doses ranging between 24 and 40.5 Gy. All patients received combined chemotherapy with various drugs: all patients received corticosteroids, and five received cis-platinum. Their follow-up ranged between 0.7 and 7.8 years (mean 3.4 years). Data on possible effects of the treatment on blood pressure, renal function as assessed by blood urea and creatinine, and kidney shrinkage as seen by serial computed tomography scanning were collected on all patients.

RESULTS

Three patients had persistent, mild elevations of urea and creatinine levels, which did not require special treatment. All three also received cis-platinum. Ipsilateral kidney shrinkage was evident in most patients. In 19 patients the craniocaudal measurement of the kidney shrank by > or = 1.6 cm. Shrinkage in other dimensions was also evident. The degree of atrophy was related to the volume of kidney irradiated. Only two patients developed hypertension, both at a low level of 150/90; one patient had had 40 Gy to the whole kidney, the other 40 Gy to half the kidney. Neither patient had elevated urea or creatinine.

CONCLUSIONS

Notwithstanding the shrinkage to the irradiated part of the kidney, the treatment did not lead to clinically significant hypertension or renal dysfunction. The administration of cis-platinum to patients with gastric lymphoma that requires kidney irradiation should be further evaluated.

Rhabdoid tumor of the kidney: a report of two cases with respective tumor markers and a specific chromosomal abnormality, del(11p13)

Malignant rhabdoid tumor is a rare, aggressive, invariably lethal tumor that is resistant to multimodal treatment. In this report, two patients with malignant rhabdoid tumor of the kidney (RTK) are described. The first patient is the first case of RKT with hyperreninemia, and the second case is also the first case with a specific chromosomal abnormality, del 11p13. The first patient presented with hematuria and a mass in the left kidney. Plasma renin, angiotensin, and aldosterone levels were elevated and paralleled the tumor progression. The karyotype of the tumor cells was normal (46,XX). In the second patient, who presented with a mass in the right kidney, the concentration of plasma tissue polypeptide antigen was elevated and paralleled the tumor progression. The karyotype of the tumor cells was 46,XX, del(11)(pter-p13::p12-qter). RTK with a cytogenetic abnormality of del(11p13), which is usually found in aniridia-Wilms' tumor syndrome, has not been known. Both patients died of metastatic disease within 7 months of diagnosis in spite of the multimodal therapy. The clinicopathology of RTK and the differences between Wilms' tumor and RTK raise compelling questions which should be the subject of future studies.

Clinical radiation nephropathy

An analysis of the normal tissue effects of irradiation of the kidney is presented. Various clinical syndromes resulting from treatment are described as well as the potential cellular basis for these findings. Effects of concurrent and/or sequential treatment with irradiation and various chemotherapeutic agents are discussed and the impact of these agents on toxicity presented. Adverse consequences of renal treatment in the child is described and possible radiation effects on so-called compensatory hypertrophy following nephrectomy presented. Renal consequences described to date of bone marrow transplantation programs utilizing irradiation are also presented. The necessity of a dose-volume histogram analysis approach to analyzing renal toxic effects in patients followed for long (> 10 year) periods is essential in developing accurate guidelines of renal tolerance.

Radiation-induced renovascular hypertension successfully treated with transluminal angioplasty: case report

Severe hypertension and stenosis of the right renal artery developed in a 21 year old male, 14 years after completion of inverted Y radiation (4000 rads) for abdominal Hodgkin's disease. Transluminal angioplasty resulted in improvement of the right kidney function, and normalization of the blood pressure for one year. Subsequently, the patient required only minimum medical therapy for blood pressure control. Transluminal angioplasty may be effective immediately in the treatment of radiation induced renal artery stenosis, although long term success remains uncertain.

Renovascular hypertension following radiotherapy and chemotherapy treated by transluminal angioplasty

A man aged 33 with poorly controlled hypertension who had been treated with radiotherapy and combination chemotherapy for testicular teratoma 8 years earlier was found on arteriography to have 75% stenosis of the left renal artery and occlusion of the right renal artery. The stenosis was dilated by transluminal angioplasty and the hypertension adequately controlled. Patients who develop high blood pressure after abdominal radiotherapy with or without chemotherapy should be investigated for renal artery stenosis.

Renal artery stenosis and hypertension after abdominal irradiation for Hodgkin disease. Successful treatment with nephrectomy

Hypertension secondary to stenosis of the left renal artery developed in a thirteen-year-old male six years after completion of inverted Y irradiation (3,600 rad) for abdominal Hodgkin disease. Surgical treatment with nephrectomy resulted in control of the hypertension without the use of antihypertensive agents. We review the literature for this unusual complication of abdominal irradiation, and recommend that a 99mTc-DMSA renal scan, selective renal vein sampling for renin determinations, and renal arteriography be performed on any patient in whom hypertension develops following abdominal irradiation in childhood.

Late effects of treatment for Wilms' tumor

Twenty-six out of a total of 49 patients who were treated for Wilms' tumor at the Mallinckrodt Institute of Radiology between January 1960 and December 1975 have survived at least five years. The median follow-up time is 153 months (12 years, 9 months). One girl, who received pelvic irradiation, has not reached puberty at age 14, but the other 25 patients are currently in good health and have no major complaints or functional impairments at present. Twenty-one patients have, however, developed some complication at some time since treatment. Serious side-effects requiring hospitalization included one case of pericarditis and one of esophageal varices secondary to portal hypertension. Both these patients, however, had advanced tumors requiring aggressive treatment and their complications should be seen in perspective. There has also been one case of temporary low grade renal failure and one of transient hypertension. More common complications were 14 instances of scoliosis (only three have had any symptoms, however), five of osseous hypoplasia, three of soft tissue hypoplasia, three of liver damage and three of lung damage. There was one case of osteochondroma within a radiotherapy field. The factors pertaining to these complications and the anticancer therapy which preceded them are discussed in detail. We conclude that, whereas structural changes following modern radiotherapy for Wilms' tumor are very common, severe dysfunctions are infrequent. Even more extended periods of observation will be required before the total number of abnormalities is ascertained. However, the striking observation from this study is the lack of late functional effects.

Renal artery stenosis in children

Because high blood pressure in children is rare and most of these patients are asymptomatic, many are overlooked until they present with a hypertensive crisis or irreparable damage. Most children with renal artery stenosis are asymptomatic and the hypertension is detected only by blood pressure recording during physical examination. Angiography is the most helpful diagnostic study. It is generally agreed that renal artery lesions in children should be considered for surgical correction. An illustrated case is described.

Postradiation renovascular hypertension

Radiation injury to arteries can represent a significant complication of therapeutic irradiation, even when the dosage used has not been excessive as judged by approved protocols. Children in whom therapeutic abdominal irradiation has been used should be monitored indefinitely for the development of hypertension. The presence of hypertension in such children with normal blood urea nitrogen (BUN) and creatinine, and without proteinuria, should prompt investigation for a renovascular lesion. Standard bypass procedures are usually effective, although the long-term success may be compromised by continuing changes in affected vessels.

Wilms' tumor--model of a curable pediatric malignant solid tumor

Wilms' tumor is the model of the treatment of a pediatric solid tumor. Initially it appeared that multi-modality therapy, consisting of transabodominal nephrectomy, post-operative radiation therapy to the tumor bed and adjuvant, single agent chemotherapy provided the highest likelihood of disease-free survival. The identification of important prognostic factors, such as histology, tumor weight, lymph node involvement and age at diagnosis has led to a re-examination of the treatment of Wilms' tumor. Future therapeutic developments will include the administration of less therapy to some well defined groups of patients, and the exploration of new programs for patients who have been demonstrated to have a poor prognosis using currently accepted treatment techniques.