Megestrol-induced Cushing's syndrome

Megace Mystery: A Case of Central Adrenal Insufficiency

Megestrol acetate (MA) is a synthetic progestin with both antineoplastic and orexigenic properties. In addition to its effects on the progesterone receptor, MA also binds the glucocorticoid receptor. Some patients receiving MA therapy have been reported to develop clinical features of glucocorticoid excess, while others have experienced the clinical syndrome of cortisol deficiency—either following withdrawal of MA therapy or during active treatment. We describe a patient who presented with clinical and biochemical features of central adrenal insufficiency. Pituitary function was otherwise essentially normal, and the etiology of the isolated ACTH suppression was initially unclear. The use of an exogenous glucocorticoid was suspected but was initially denied by the patient; ultimately, the culprit medication was uncovered when a synthetic steroid screen revealed the presence of MA. The patient's symptoms improved after she was switched to hydrocortisone. Clinicians should be aware of the potential effects of MA on the hypothalamic-pituitary-adrenal (HPA) axis.

Effects of muscle strength training and megestrol acetate on strength, muscle mass, and function in frail older people

OBJECTIVES

To determine the independent and combined effects of progressive resistance muscle strength training (PRMST) and megestrol acetate (MA) on strength, muscle mass, and function in older recuperative care patients.

DESIGN

Double-blind, randomized, controlled intervention using a two-by-two factorial design and conducted between 1999 and 2001.

SETTING

University-affiliated Department of Veterans Affairs hospital.

PARTICIPANTS

Twenty-nine patients (mean age 79.4 +/- 7.4, 90% white) aged 65 and older and had recent functional decline.

INTERVENTIONS

After randomization to one of four treatment groups (low-resistance exercises plus 800 mg per day of MA or a placebo or high-intensity PRMST plus 800 mg/d of MA or placebo), subjects received training and the drug or placebo for 12 weeks.

MEASUREMENTS

Change in muscle strength, mid-thigh muscle area, and aggregate functional performance score as assessed using analysis of covariance.

RESULTS

Five subjects withdrew from the study before its completion. Based on intent-to-treat analyses, subjects who received high-intensity PRMST and placebo experienced the greatest strength gains. The addition of MA was associated with worse outcomes than with high-intensity exercise training alone, especially with regard to the leg exercises. Post hoc analysis demonstrated that subjects who received high-intensity PRMST and placebo experienced significantly greater percentage increases in leg strength than subjects in either of the MA treatment groups (P<.05 for each comparison). There was also a significant negative effect of MA on physical function. In general, subjects who received MA experienced a deterioration in aggregate physical function scores, whereas the remaining subjects improved (-0.80+/-0.40 vs 0.48+/-0.41, P=.04). There was not a significant interaction between exercise and MA for any outcome.

CONCLUSION

High-intensity PRMST is a safe and well-tolerated exercise regimen for frail elderly patients. The addition of MA appears to blunt the beneficial effects of PRMST, resulting in less muscle strength and functional performance gains.

High prevalence of adrenal suppression during acute illness in hospitalized patients receiving megestrol acetate

INTRODUCTION

Megestrol acetate (MA) is a progestational agent used for palliation of breast and endometrial cancer. The drug promotes weight gain via appetite stimulation. This property has led to widespread use in patients with wasting illnesses. Increasing numbers of reports suggest glucocorticoid activity.

OBJECTIVE

Unrecognized adrenal suppression may result from MA use. This is the first study to examine the prevalence of adrenal suppression in hospitalized patients treated with MA.

SUBJECTS AND DESIGN

This is a cross-sectional study of hospitalized patients receiving MA compared to control subjects. Morning cortisol levels, endocrine signs and symptoms, and duration of MA therapy were evaluated in 28 hospitalized medical patients treated with MA, and 21 control patients admitted to the same hospital service during the study period.

RESULTS

Median cortisol levels were significantly lower in patients using MA vs controls (160 vs 386 nmol/l, p=0.003). Forty-three percent of subjects on MA demonstrated morning cortisol levels below the normal range (138-690 nmol/l), compared with 10% of controls (p=0.013). Ninety-three percent of subjects taking MA had morning cortisol levels below the level that excludes adrenal insufficiency in hospitalized patients (497 nmol/l) vs 71% of controls (p=0.06).

CONCLUSIONS

MA use is associated with significant adrenal suppression in acutely ill individuals. This should alert physicians to the possibility of adrenal insufficiency and the need to assess for signs or symptoms of adrenal insufficiency, and mandates a low threshold for testing adrenal function in hospitalized patients taking MA.

Osteoporosis associated with megestrol acetate

Megestrol acetate is a progestational agent for treatment of metastatic breast cancer and endometrial cancer. Megestrol has also been used as an appetite stimulant for patients with human immunodeficiency virus and malignancy who experience cachexia and wasting; also, megestrol can be beneficial in relieving hot flashes in women and men. Megestrol has been shown to have a glucocorticoidlike effect and has been associated with substantial suppression of plasma estradiol levels. We describe 2 patients who recently presented to our Metabolic Bone Disease Clinic with severe osteoporosis complicated by multiple vertebral fractures experienced while the patients were receiving high-dose megestrol therapy. The patients had evidence of adrenal axis suppression but recovered fully after megestrol was discontinued. We speculate that megestrol was an important factor in the development of osteoporosis and subsequent fractures. Further study is warranted to clarify the relationship between megestrol and its potential for adversely affecting the skeleton.

Mechanism of transient adrenal insufficiency with megestrol acetate treatment of cachexia in children with cancer

Megestrol acetate (MA) is used to stimulate appetite in children with cancer, but it can impair adrenal function and cause adrenal insufficiency. Three children with brain tumors were treated with MA to improve weight gain. Standard low-dose ACTH stimulation tests were performed on and off MA. All patients failed the low-dose ACTH stimulation while on MA and responded normally once off MA. The suppression of the adrenal axis was at the level of the hypothalamus/pituitary. Adrenal suppression can occur in patients treated with MA. Awareness of this possibility and the use of glucocorticoid stress coverage are advised.

A low-dose adrenocorticotropin test reveals impaired adrenal function in cancer patients receiving megestrol acetate therapy

Megestrol acetate (MA) has glucocorticoid activity and can induce significant secondary adrenal suppression. We designed this study to determine the extent of adrenal insufficiency in cancer patients receiving MA by utilising a sensitive low-dose adrenocorticotropin (ACTH) stimulation test. Adrenal function was assessed by a low-dose (0.625 microg) ACTH (1-24) stimulation test in 30 patients receiving MA for metastatic cancer. 10 of the patients who failed this test underwent a standard (250 microg) test on another day. Adrenal function was also evaluated in 15 of the patients by measuring the excretion of free cortisol in 24-h urine samples. Peak serum cortisol levels following stimulation with low-dose (0.625 microg) ACTH (1-24) were <18 microg/dl in 16 of 30 (53%) patients, of whom 9 had a basal serum cortisol level of <5 microg/dl. Five of 16 poor responders to the low-dose test showed normal stimulation with the standard (250 microg) ACTH (1-24) test. Thus, adrenal insufficiency would fail to be detected by the standard high dose test in these patients. Patients who failed the low-dose ACTH (1-24) test had lower 24-h urinary free cortisol excretion (8.7+/-10.3 microg/24 h) than normal responders (35+/-12.7 microg/24 h). Impaired adrenal function is common in cancer patients receiving MA. The low-dose ACTH (1-24) test is apparently capable of revealing adrenal insufficiency undetected by the standard high-dose ACTH test. Patients receiving MA might have inadequate adrenal function during episodes of infection or after withdrawal of MA therapy and this may require prompt corticosteroid treatment.

Megestrol-induced Cushing syndrome

OBJECTIVE

To report a case of Cushing syndrome associated with megestrol acetate therapy in a patient with renal insufficiency.

SUMMARY

A 17-year-old boy with renal insufficiency due to unilateral renal agenesis developed Cushing syndrome and worsening of his renal function after megestrol acetate therapy. The diagnosis was based on clinical and analytical evaluation.

DISCUSSION

Megestrol acetate is indicated for the treatment of cachexia associated with AIDS and malignancy. Due to its glucocorticoid activity, megestrol use has resulted in the occurrence of Cushing syndrome in both patient groups. We report the case of a young patient with renal insufficiency due to unilateral renal agenesis who developed Cushing syndrome two months after administration of high-dose (900-mg/d) megestrol acetate for an eating disorder.

CONCLUSIONS

The risk of megestrol-induced Cushing syndrome, especially with high doses of the medication, should be considered as a possible adverse effect in patents with renal insufficiency.

Managing cancer-related anorexia/cachexia

Cancer-related anorexia/cachexia (CAC) is a complex phenomenon in which metabolic abnormalities, proinflammatory cytokines produced by the host immune system, circulating tumour-derived catabolic factors, decreased food intake, and probably additional unknown factors, all play different roles. This review examines the mechanisms of CAC and its management. All the potential modalities of intervention from nutritional to pharmacological approaches are included with a clear distinction between unproven, investigational and well established treatments. Among the latter, the progestogens are currently considered the most effective and safest drugs for the management of CAC. Agents currently under investigation for CAC include thalidomide, pentoxifylline and melatonin, which most probably act on cytokine release, and clenbuterol, which acts on muscle mass and to antagonise protein wasting. Our personal experience with the synthetic progestogens megestrol and medroxyprogesterone supports their use as first-line agents. In addition, our work on the potential role of antioxidant agents in counteracting the oxidative stress, which appears to be involved in CAC, shows them to be promising agents when used in combination chemotherapy regimens either alone or with other 'biologics'. There is an ongoing need for quality of life questionnaires which specifically address the most significant symptoms present in patients with CAC.

Randomized, double-blind, placebo-controlled pilot trial of megestrol acetate in malnourished children with cystic fibrosis

BACKGROUND

Undernutrition is common in patients with cystic fibrosis (CF). Nutritional rehabilitation has been shown to improve linear growth, pulmonary function, well-being, and resistance to infection in this population. The purpose of this study was to determine whether the administration of megestrol acetate (MA) induces weight gain in malnourished patients with CF, and to assess the composition of weight gain.

METHODS

In a randomized, placebo-controlled, double-blind, crossover study, 12 children with CF received MA (10 mg/kg/d) or placebo for 12 weeks, followed by a 12-week washout period, then the alternative treatment. Anthropometrics, caloric intake, and clinical assessment were obtained every 6 weeks; pulmonary function tests, biochemistry, hematology, cortisol, growth hormone, insulin, C-peptide, insulin-like growth factor-1, insulin-like growth factor binding protein-3, and dual-energy x-ray absorptiometry scans were obtained every 12 weeks.

RESULTS

Six children did not complete the study, three for reasons unrelated to the study, two because they developed diabetes while receiving MA, and one who had glucose intolerance while receiving the placebo. Average weight gain was 3.05 kg in the MA group and 0.3 kg in the placebo group. The change in weight z score was +0.76 in the MA group and -0.05 in the placebo group. The change in height z score was -0.06 in the MA group and +0.06 in the placebo group. Lean body mass and body fat increased by 1507 g and 1192 g respectively in the MA group. Pulmonary function tests improved in the MA group; serum cortisol levels decreased. Side effects included glucosuria, insomnia, hyperactivity, and irritability.

CONCLUSIONS

Weight, body fat, and lean body mass increased and pulmonary function improved in the children with CF given MA. Adrenal suppression, glucose intolerance, and diabetes are side effects.

Striae formation in two HIV-positive persons receiving protease inhibitors

Steroidal side effects such as "buffalo hump" and visceral abdominal fat accumulation have been reported in association with protease inhibitors. We report two cases of severe disfiguring striae formation in patients with HIV who recently started indinavir therapy. These changes occurred within 3 months of starting treatment.

Endocrine implications of human immunodeficiency virus infection

Endocrine abnormalities occur frequently in HIV-infected patients. Although the majority of endocrine disorders reflect chronic infection, stress, and malnutrition, some disorders are characteristic of HIV infection or AIDS and deserve particular clinical attention. Identification of HIV patients at risk of frank endocrine disorders, rapid and correct diagnosis, and appropriate management are essential steps to minimize morbidity and mortality. Finally, increasing evidence from in vitro studies suggests that various hormones may influence HIV replication as well as the course of HIV disease and associated disorders. Future studies on the molecular mechanisms of hormones on HIV action and clinical studies on the effects of hormones as adjunctives to established forms of therapy may stimulate development of novel therapeutic strategies that will benefit HIV-infected patients.

Anorexia during acute and chronic disease

Anorexia is associated with disorders of all systems. Anorexia represents a consistent clinical manifestation during acute and chronic pathophysiological processes (infection, inflammation, injury, toxins, immunological reactions, malignancy and necrosis). Anorexia during disease can be beneficial or deleterious depending on the timing and duration. Temporary anorexia during acute disease may be beneficial to an organism since a restriction in the intake of micro- and macro-nutrients will inhibit bacterial growth. Long-term anorexia during chronic disease, however, is deleterious to an organism and may be associated with cachexia, which can ultimately result in death. Various mechanisms participate in the anorexia observed during disease, including cytokine action. Anorexia induced by cytokines is proposed to involve modulation of hypothalamic-feeding associated sites, prostaglandin-dependent mechanisms, modifications of neurotransmitter systems, gastrointestinal, metabolic, and endocrine factors. In addition, the anorexia-cachexia syndrome is multifactorial and may involve chronic pain, depression or anxiety, hypogeusia and hyposmia, chronic nausea, early satiety, malfunction of the gastrointestinal system, metabolic alterations, cytokine action, production of other anorexigenic substances and/or iatrogenic causes (chemotherapy, radiotherapy). Cachexia may result not only from anorexia and a decreased caloric intake, but also from malabsorption and losses from the body (ulcers, hemorrhage, effusions), or a change in body metabolism. Research has focused on potential interventions to modify anorexia during disease and the anorexia-cachexia syndrome. Nutritional modifications and the use of specific steroids (such as megestrol acetate) are being tested in the clinical setting. Understanding the specific mechanisms responsible for anorexia during disease as well as their interactions is essential to develop interventions for the control of anorexia (during a critical time in a specific disease), and to devise less toxic immunotherapeutic regimens using cytokines.