Cholestatic jaundice and aminoglutethimide

Aminoglutethimide in Advanced Breast Cancer

From July 1980 to June 1983, 61 postmenopausal women with progressive metastatic breast cancer were treated with aminoglutethimide, 250 mg 4 times daily, plus cortisone acetate, 25 mg twice daily. Of 51 evaluable patients, an objective remission was observed in 22 (43 %) (partial remission in 19, complete in 3), stable disease in 14 (27 %), and progressive disease in 15 (30 %). The median duration of response was 60 weeks (range 12 +; 94+). The response rate was higher when the dominant disease site was soft tissue (50 %) or bone (56 %) rather than viscera (29 %). Side effects were common but usually slight and transient. Somnolence (69 %), dizziness (41 %), nausea (35 %) and skin rash (27 %) were the most frequent. Serum levels of gamma-GT, alkaline phosphatase and total cholesterol rose during aminoglutethimide treatment, whereas levels of uric acid and indirect bilirubin decreased. Aminoglutethimide plus cortisone acetate appears to be an active and relatively safe treatment in advanced breast cancer and may be recommended as second-line endocrine treatment.

Mechanisms of action of aminoglutethimide as endocrine therapy of breast cancer

During the last decade aminoglutethimide has been recognised as a valuable alternative in endocrine therapy for advanced breast cancer. Although some side effects do occur, most often these are initial effects which subside within a few weeks, and cessation of therapy is not usually indicated. Aminoglutethimide was originally introduced as an inhibitor of steroidogenesis in the adrenal cortex. It was soon recognised, however, that inhibition of the non-glandular aromatase, blocking the conversion of androgenic prohormones to oestrogens, was more important, resulting in decreased blood levels of oestrogens. In this review the role of aromatase inhibition as the only important aspect of the mechanism of action of aminoglutethimide is challenged. Evidence has accumulated during the last few years that aminoglutethimide is a most potent inducer of microsomal enzymes. In addition to the pharmacological implications this has (suggesting important interactions), it also points to the possibility that levels of oestrogens are decreased due to accelerated metabolism of these hormones. Based on new experimental data, and also clinical work with alternative aromatase inhibitors, it appears that the antitumour activity of aminoglutethimide may be due to both aromatase inhibition and accelerated metabolism of oestrogens. This seriously challenges the importance of aromatase inhibition alone as a strategy in endocrine therapy of breast cancer, and furthermore suggests that accelerated metabolism of key hormones is an alternative strategy to be explored.

Drug-induced cholestasis

Acute, drug-induced hepatocellular cholestasis (either pure or cholestatic hepatitis) is a common manifestation of drug-induced hepatic injury. The drugs most frequently responsible are hormonal steroids and psychopharmacological agents (in particular phenothiazines and some antidepressants). Cholestasis usually subsides without sequelae in less than six months. Acute, drug-induced ductular cholestasis is uncommon and can resemble biliary tract obstruction. Complete recovery occurs promptly after the withdrawal of the causative drug in most cases. The pathogenetic mechanism may be immunoallergic. Prolonged ductular or ductal cholestasis can follow drug-induced acute hepatitis despite prompt withdrawal of the offending drug. This syndrome, observed mainly with chlorpromazine and uncommonly with twenty other drugs, is characterized by the progressive disappearance of small bile ducts and by manifestations mimicking primary biliary cirrhosis. However, its prognosis appears to be better than that of primary biliary cirrhosis, the condition being reversible in the majority of cases or even subsiding completely. The mechanism is still unknown, but several features suggest some form of autoimmunity. Extrahepatic cholestasis related to sclerosing cholangitis is a frequent and long-term complication of intra-arterial infusion of floxuridine in patients treated for hepatic metastases from colorectal carcinoma. Although it may be reversible, floxuridine-induced sclerosing cholangitis has a poor prognosis and can lead to death in a few patients. The mechanism is probably related to the vascular supply of the common hepatic duct and its relationship to the perfusion territory of floxuridine.

Drug-induced cholestasis

Intrahepatic cholestasis, defined as arrested bile flow, mimics extrahepatic obstruction in its biochemical, clinical and morphological features. It may be due to hepatocyte lesions of which there are three types, termed canalicular, hepatocanalicular and hepatocellular, respectively; or it may be due to ductal lesions at the level of the cholangiole or portal or septal ducts. Defective bile flow due to hepatic lesions reflects abnormal modification of the ductular bile. Defective formation of canalicular bile may involve bile acid-dependent or independent flow. It appears to result most importantly from defective secretion of bile acid-dependent flow secondary to defective uptake from sinusoidal blood, defective transcellular transport and defective secretion; or from regurgitation of secreted bile via leaky tight junctions. An independent defect in bile acid-independent flow is less clear. Defective flow of bile along the canaliculus may reflect increased viscosity and impaired canalicular contractility secondary to injury of the pericanalicular microfibrillar network. Impaired flow beyond the canaliculus may result from ductal injury. Sites of lesions that contribute to cholestasis include the sinusoidal and canalicular plasma membrane, the pericanalicular network and the tight junction and, less certainly, microtubules and microfilaments and Golgi apparatus. A number of drugs that lead to cholestasis have been found to lead to injury at one or more of these sites. Other agents (alpha-naphthylisothiocyanate, methylenedianiline, contaminated rapeseed oil, paraquat) lead to ductal injury resulting in cholestasis. Reports of inspissated casts in ductules (benoxaprofen jaundice) and injury to the major excretory tree (5-fluorouridine after hepatic artery infusion) have led to other forms of ductal cholestasis. Most instances of drug-induced cholestasis present as acute, transient illness, although important chronic forms also occur. The clinical features include the reflection of the cholestasis (pruritus, jaundice), systemic manifestations and extrahepatic organ involvement. While nearly all classes of medicinal agents include some that can lead to cholestasis, there are differences among the various categories. Phenothiazines and related antipsychotic and 'tranquillizer' drugs characteristically lead to cholestatic hepatic injury. The tricyclic antidepressants may lead to cholestatic or hepatocellular injury.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment of adrenocortical carcinoma: a case report and review of the literature

A case report of adrenocortical carcinoma is presented, and its natural history and treatment are discussed. Adrenocortical carcinoma is a rare malignant disease. The mean survival time for untreated patients is less than three months. The tumor is classified as functioning or nonfunctioning depending on biochemical and clinical evidence of steroid overproduction. Surgical resection of the tumor is the primary treatment. Chemotherapy is indicated for antitumor and antihormonal effects. Mitotane is a direct adrenolytic, and is the only drug currently available that has extended survival in patients with this disease. Its clinical usefulness is limited by its gastrointestinal and neurological toxicity. Aminoglutethimide inhibits steroid synthesis by blocking the conversion of cholesterol to pregnenolone. It has no antitumor effect in adrenocortical carcinoma, but is effective in relieving the signs and symptoms of excessive hormone production in functioning tumors. Both mitotane and aminoglutethimide have complex mechanisms of action. Their combined use in the treatment of adrenocortical carcinoma requires a complete understanding of their individual actions and awareness of the potential for additive effects, both therapeutic and toxic.