Aminoglutethimide as treatment of postmenopausal women with advanced breast carcinoma

Hormone-dependent breast carcinomas respond to deprivation of biologically active estrogens with objectively quantifiable tumor regression. Aminoglutethimide, a known inhibitor of steroid synthesis, is also a potent blocker of the aromatase enzyme and, thus, of estrogen production. We developed an effective regimen to inhibit estrogen production in postmenopausal women using aminoglutethimide and replacement glucocorticoid. One hundred forty-seven women initially received aminoglutethimide and replacement glucocorticoid as treatment of metastatic breast carcinoma. One hundred twenty-nine women are currently evaluable for assessment of clinical and hormonal responses. Thirty-seven percent of unselected women and 49% of estrogen receptor-positive patients experienced objective tumor regression. Responses occurred predominantly in soft tissue (47%) and bone (35%) and lasted 30 +/- 9.1 months for complete and 14 +/- 1.5 months for partial regressions. Plasma and urinary estrogen levels fell equally in responder versus nonresponder groups whereas androgen levels declined less in patients with progressive disease.

Tamoxifen versus aminoglutethimide in advanced breast carcinoma: a randomized cross-over trial

Altogether 117 patients with advanced breast cancer were treated with either tamoxifen 10 mg by mouth twice daily or aminoglutethimide 250 mg by mouth four times daily with hydrocortisone 20 mg twice daily in a randomised cross-over trial in which patients who failed to respond to the first treatment or relapsed while receiving it were switched to the other. Eighteen (30%) out of 60 patients initially treated with tamoxifen achieved an objective response and 11 (18%) showed stable disease. Seventeen (30%) out of 57 patients treated initially with aminoglutethimide achieved an objective response and 13 (23%) achieved stable disease. Objective responses in bone metastases were achieved more commonly with aminoglutethimide (11 patients (35%)) than with tamoxifen (five (17%)). The predicted median duration of response for tamoxifen was 15 months and for aminoglutethimide over 15 months (no significant difference). Five (15%) out of 34 patients who failed to respond to tamoxifen and four out of six patients who relapsed after responding to tamoxifen subsequently responded to aminoglutethimide. In contrast, only two (6%) out of 31 patients who failed to respond to aminoglutethimide and none out of four patients who relapsed while receiving aminoglutethimide subsequently responded to tamoxifen. The main side effects occurring in the 97 patients who received aminoglutethimide as first- or second-line treatment were lethargy and drowsiness (36 patients) and rash (29); seven patients had to stop treatment because of side effects. In contrast, side effects were rare and mild with tamoxifen and no patient had to stop treatment because of them. Both tamoxifen and aminoglutethimide appeared from this study to be equally effective in the medical endocrine treatment of advanced breast cancer.

Tamoxifen and aminoglutethimide in the management of patients with advanced endometrial carcinoma not responsive to medroxyprogesterone

Eleven patients with advanced endometrial carcinoma not responsive to medroxyprogesterone were entered into a trial of therapy with tamoxifen, aminoglutethimide or both in combination. Two patients had a complete response, 1 to aminoglutethimide and 1 to tamoxifen. One patient who initially had a partial response to tamoxifen but then relapsed, had a partial response to aminoglutethimide. Two patients had stable disease for 8 and 6 months on aminoglutethimide, and 1 patient who initially showed no response to tamoxifen has had stable disease for 14 months since addition of aminoglutethimide to therapy. The relative lack of toxicity of these drugs make their use attractive in the management of such patients.

[Aminoglutethimide in metastasizing carcinoma of the breast resistant to hormonal and cytostatic treatment (author's transl)]

Aminoglutethimide (Elipten), at a dosage between 250 and 1500 mg/d by mouth, was administered in a clinical phase II study to 17 patients with metastasizing carcinoma of the breast resistant to hormones and cytostatic drugs. Results of this treatment were available for 14 patients. Nine women were given the drug alone, eight in combination with cytostatic drugs. In 11 women the drug significantly decreased pain within 3-14 days. Used alone aminoglutethimide produced objective regression of the metastases in two women, two further instances of regression occurred when the drug was combined with cytostatic agents. Five women developed urticarial rash, while six had somnolence and nausea or lethargy. Aminoglutethimide is suitable for symptomatic treatment of metastasizing treatment-resistant carcinoma of the breast, either alone or in combination with cytostatic drugs.

A randomized trial comparing surgical adrenalectomy with aminoglutethimide plus hydrocortisone in women with advanced breast cancer

We randomized 96 postmenopausal women with metastatic breast carcinoma to receive surgical adrenalectomy or medical therapy with an adrenal inhibitor, aminoglutethimide (AG), plus replacement hydrocortisone. Before randomization, women were stratified according to disease-free interval, site of dominant disease, and estrogen-receptor status. Of 40 evaluable women treated with AG and hydrocortisone, 53 per cent had objective responses, as compared with 45 per cent of 29 women undergoing surgical adrenalectomy (P value not significant). Responses lasted a mean of 17.2 months in the medical group and greater than 17.1 months in the surgical group (not significant). Estrogen levels fell similarly in response to either treatment, whereas AG and hydrocortisone preserved androgen production. A null hypothesis tested the single question asked by this study: "Is surgical adrenalectomy superior to treatment with AG and hydrocortisone?" Rejection at significance levels of P = 0.01 and P = 0.07 for differences of 20 per cent and 10 per cent, respectively, suggested that medical therapy with AG and hydrocortisone may be logically chosen in place of surgical adrenalectomy.

Oestrogen receptors and the response of metastatic breast cancer to aminoglutethimide or tamoxifen

Oestrogen receptor (ER) measurements in metastatic and primary tumours from patients with breast cancer have been correlated with the objective tumour response to treatment with aminoglutethimide (24 patients) or tamoxifen (39 patients). The rate of response in patients with ER-positive tumours (aminoglutethimide 69%, tamoxifen 70%) was significantly greater than in those with ER-negative tumours (aminoglutethimide 9%, tamoxifen 10%). Five of six patients showing an objective response to tamoxifen treatment responded later to aminoglutethimide, whereas only two of 12 patients who had not responded to tamoxifen responded later to aminoglutethimide. Toxicity rates were low for tamoxifen (5%), and reasonably low with aminoglutethimide (20%). Because of the low toxicity of tamoxifen, this agent could reasonably be used in breast cancer regardless of the availability of tumour ER measurements. The use of aminoglutethimide could be based either on the presence of ER in the tumour or on the response to previous tamoxifen therapy.

Treatment of metastatic breast cancer with aminoglutethimide

Seventy-three women with metastatic breast cancer were treated with aminoglutethimide and dexamethasone. No complete responses occurred. Ten patients (16%) achieved partial responses (mean duration, 12 months). The proportions of patients responding by disease site were breast (50%), nodes (33%), skin (23%), bone (16%), lung (11%), and liver (7%). Response did not correlate with age, menopausal status, performance status, or cortisol suppression. Ninety percent of responders had had previous responses to hormonal manipulations. No responses occurred in estrogen receptor negative patients. An additional 20% of patients had disease stabilization of eight or more months (mean, 17 months). Severe bone pain was present in 47 patients and was relieved in 19. Side effects occurred in 75% but caused discontinuation of therapy in only four patients. Somnolence, nausea, rash, Cushings syndrome, and leukopenia were the most frequent side effects. Aminoglutethimide with dexamethasone is an effective hormonal treatment for metastatic breast cancer.

Aminoglutethimide therapy in advanced breast cancer

Aminoglutethimide inhibited adrenal steroid synthesis, as assessed by serial estimations of plasma dehydroepiandrosterone sulphate in ten patients with advanced breast cancer. There was a favourable response in seven out of the ten patients, and in four there was an objective remission using UICC criteria. Favourable responses were more common in patients who had shown similar responses to previous endocrine therapy, especially a response to tamoxifen. Side effects were mild: two patients exhibited a drug sensitivity reaction, but neither required cessation of therapy. Adrenal suppression by aminoglutethimide is effective and well tolerated, and is therefore preferable to surgical adrenalectomy in the treatment of advanced breast cancer.

Serum aminoglutethimide levels: studies of serum half-life, clearance, and patient compliance

Serum aminoglutethimide was measured in 13 women with mastastatic breast carcinoma who were treated with 1.0 Gm aminoglutethimide and 40 mg hydrocortisone daily over a period of one year. Serum concentrations of aminoglutethimide were used to evaluate drug half-life, clearance, and patient compliance. Mean half-life and clearance rates were determined in six patients. The mean half-life of aminoglutethimide prior to therapy was 13.3 +/- 2.65 (S.D.) hours and fell significantly (P less than 0.01) to 7.3 +/- 2.14 hours after six to 32 weeks of therapy. The mean clearance rate prior to therapy was 2.58 +/- 0.33 (S.D.) 1./hour and increased significantly (P less than 0.01) to 5.29 +/- 1.4 1./hour after therapy. The mean serum concentration was 11.5 +/- 3.6 microgram/ml in seven patients. No significant variation of mean aminoglutethimide concentration from the overall mean was noted during the course of therapy. We conclude that serum aminoglutethimide concentrations are useful in evaluating patient compliance. Our data also suggest that aminoglutethimide increases its own metabolism, which may explain the absence of toxicity symptoms seen late in the treatment period.

Pancytopenia induced by aminoglutethimide in the treatment of breast cancer

Aminoglutethimide is an investigational agent of proven benefit in the treatment of metastatic breast carcinoma. We report herein a case of aminoglutethimide-induced pancytopenia complicated by bleeding and gram-negative septicemia. Severe pancytopenia is a rare but important side effect of this new drug and is rapidly reversible when the agent is withdrawn.

Aminoglutethimide in treatment of metastatic breast carcinoma

42 patients with metastatic breast carcinoma were treated with aminoglutethimide, which inhibits adrenal steroid hormone synthesis. Treatment was stopped in 2 patients before response could be assessed; of the other 40, 15 (37.5%) had an objective response, 1 (2.5%) showed a response in bone but not in soft tissue, and 4 (10%) had complete or very great relief of metastatic bone pain but no radiological evidence of improvement. 19 (53%) of 36 patients with bone metastases responded to treatment (15 had X-ray evidence and 4 had pain relief), as did 5 (45%) of 11 patients with soft tissue metastases, 2 (25%) of 8 with malignant marrow infiltration, 1 (14%) of 7 with lung metastases, and none of 13 with liver metastases. Response was commonest in patients who had previously responded to other forms of endocrine therapy. Side-effects, usually mild and transient, occurred in a few patients; the most important were an initial period of somnolence in 9 patients and a rash in 5.

Medical adrenalectomy with aminoglutethimide: clinical studies in postmenopausal patients with metastatic breast carcinoma

The use of adrenalectomy and hypophysectomy in the management of postmenopausal patients with metastatic breast carcinoma is reserved for highly selected patients. As an alternate approach, a pharmacologic method of inhibiting adrenal cortical secretion was developed which consisted of the daily administration of 1000 mg of aminoglutethimide to block steroidogensis and either dexamethasone (2.0-3.0 mg/day) or hydrocortisone (40-60 mg/day) as replacement glucocorticoid. This regimen markedly suppressed plasma levels of DHA-S, androstenedione, estrone, and estradiol, and urinary levels of aldosterone. Of 50 patients treated, 19 (38%) demonstrated either a complete (8/19) or a partial (11/19) objective disease remission which lasted for 18.05 +/- 3.1 months (mean +/- SEM). In 10 (20%) patients, there was stabilization of disease (7.8 +/- 1.2 months), accompanied by symptomatic relief of bone pain in six (12%). There was disease progression in 20 (40%) patients. The acute side effects of aminoglutethimide therapy were significant and consisted of transient lethargy (41.5%) and a cutaneous rash (35.8%). Chronic toxicity was negligible. The medical adrenalectomy regimen of aminoglutethimide plus glucocorticoid offers a suitable alternative to surgical adrenalectomy or hypophysectomy in the management of postmenopausal patients with metastatic breast carcinoma.

Kinetic, hormonal and clinical studies with aminoglutethimide in breast cancer

Approximately one-third of patients with metastatic breast carcinoma respond to surgical ablative therapy but the morbidity associated with these procedures has limited their use to highly selected patients. Consequently, a chemical method of adrenal suppression was developed using a potent inhibitor of adrenal steroid synthesis, aminoglutethimide, in combination with a synthetic glucocorticoid, dexamethasone. While this regimen effectively blocked adrenal function, it was complicated by a drug interaction in which aminoglutethimide accelerated the metabolism and reduced the bioavailability of dexamethasone. To overcome this problem, a new regime using aminoglutethimide and hydrocortisone, a glucocorticoid less susceptible to altered metabolism, was developed. Kinetic studies confirmed that aminoglutethimide does not interact with hydrocortisone to alter its rate of metabolism. Hormone measurements established that 1000 mg of aminoglutethimide and 40 mg of hydrocortisone daily suppressed DHA-sulfate, androstenedione, estrone, estradiol and aldosterone to a greater extent than the prior protocol using aminoglutethimide and 2-3 mg of dexamethasone. Patients experienced objective tumor regression with equal frequency while receiving the aminoglutethimide-hydrocortisone regimen or aminoglutethimide and dexamethasone and the overall rate of response in 50 evaluable patients was 38%. Side effects occurred frequently in the first few weeks of treatment but disappeared nearly uniformly thereafter. The present aminoglutethimide-hydrocortisone regimen is simple, non-toxic, effective in inhibiting estradiol synthesis and capable of inducing tumor regression as frequently as previously reported with adrenalectomy.

Medical and surgical adrenalectomy in patients with advanced breast carcinoma

Twenty-four postmenopausal patients with metastatic breast carcinoma were placed on aminoglutethimide and dexamethasone as a form of reversible medical adrenalectomy. Six patients experienced adverse side-effects. Of the 18 remaining patients 50% had a definite subjective or objective response to therapy. Thirteen of these patients underwent subsequent surgical adrenalectomy after a maximum of 3 month's trial of the medical regimen. In every patient the response to therapy was identical with the two modalities of therapy. In those postmenopausal patients with metastatic breast cancer who are felt to have a hormone- dependent tumor by clinical and/or hormonal assay criteria, medical adrenalectomy may eventually be a feasible replacement for surgery in selected cases. As important, perhaps, is the potential value of this medical adrenalectomy as a reliable indicator of the subsequent response to endocrine ablative therapy.

Aminoglutethimide in the treatment of Cushing's syndrome

The efficacy and tolerability of aminoglutethimide for the treatment of Cushing's syndrome was assessed in 66 cases three of which are described in the present paper. Aminoglutethimide provided palliation from the signs and symptoms of hypercorticism in 13 of 21 patients with metastatic adrenocortical carcinoma and four of six patients with ectopic ACTH production due to metastatic carcinomas. All six of the patients with adrenal adenomas showed clinical and biochemical improvement, while 14 of the 33 patients with bilateral adrenal hyperplasia of pituitary origin improved. Adverse reactions attributed to aminoglutethimide such as drowsiness, rash, and nausea occurred in 58 per cent of cases. These data suggest that aminoglutethimide has a place in controlling the signs and symptoms of adrenocorticoid excess in patients with Cushing's syndrome due to malignancy and is effective preoperative therapy for patients with adrenal adenomas and bilateral hyperplasia.

Aminoglutethimide medical adrenalectomy for advanced prostatic carcinoma

Complete adrenal suppression with aminoglutethimide has been accomplished in 7 patients with progressive stage D carcinoma of the prostate who had become refractory to orchiectomy and the administration of exogenous estrogens. A favorable response was noted in 3 patients. These preliminary results indicate that this agent may be as useful as surgical adrenalectomy in the treatment of progressive prostatic carcinoma. A brief discussion of the pharmacology of this agent, its mode of administration and the side effects are presented.

Ultrastructural changes of the adrenal cortex in Cushing's syndrome treated with aminoglutethimide (Elipten Ciba)

The main ultrastructural feature of human adrenal cortices following administration of aminoglutethimide (Elipten CIBA), a steroid biosynthesis blocking agent, is a striking intracellular accumulation of lipids, also seen in the light microscopy. The lipids accumulate in the adrenocortical cells but are also stored in the cytoplasm of pericapillary histiocytes. The lipids are present in the adrenocortical cells mostly as rounded liposomes of variable size, whereas those in the histiocytes usually show up as an amorphous debris with abundant myelin figures and cholesterol crystals. In some areas of the adrenal cortex activated histiocytes changing into lipophages may become the prevalent cell. They also take the place of destroyed adrenocortical cells and can form compact cell aggregates of variable size or even columnar strands between neighbouring capillaries, thus resembling columns of adrenocortical cells. In some of the adrenocortical cells focal cytoplasmic degradation, turning into coagulation necrosis, was observed. In others initial cytolysis was found. In contrast with earlier findings in experimental animals, mitochondrial changes in humans were not a prominent feature. The only changes occasionally observed were a focal disappearance of the vesicular cristae and a concomitant fibrillary loosening of the mitochondrial matrix.

Cushing's syndrome associated with a bronchial adenoma. Possible periodic hormonogenesis

Diagnostic and therapeutic problems in a patient with ectopic ACTH syndrome caused by a malignant bronchial adenoma are discussed. Persistent Cushing's syndrome was present following apparent total adrenalectomy, but radioactive scanning with 131I-19-iodocholesterol showed the presence of residual adrenal tissue in the right suprarenal bed. Amelioration of the hypercortisolism occurred after removal of the bronchial adenoma. A paradoxical elevation of adrenocortical activity followed administration of dexamethasone and data are presented which suggest that periodic secretion of ACTH accounted for this phenomenon.