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This report describes a patient with a recurring, one stemline-aneuploid, adrenocortical carcinoma. The condition showed a number of unusual characteristics over a period of 22 yr. It changed from a biochemically functioning, low-grade malignant tumour into a non-functioning malignancy with pronounced mitotic activity, accompanied by an ovarian carcinosarcoma 1 yr before death. Quality of life was reasonable for many years despite chemotherapy, consisting of a total of almost 10 kg of o,p'-DDD administered over a period of 8 yr, and the subsequent side effects (e.g. low T4; increased bleeding time). A reduced mineralocorticoid activity, induced by o,p'-DDD, was reversed after discontinuation of o,p'-DDD treatment. During o,p'-DDD administration the substitution requirements for both hydrocortisone and fludrocortisone acetate increased, leading to periods of hypoadrenocorticism with prerenal uraemia.

We found that the distribution of the lipophilic chemotherapeutic agent o,p'-DDD (mitotane) among serum (lipo)proteins was altered in hypertriglyceridemia, with relatively more o,p'-DDD accumulating in the chylomicron and very-low-density lipoprotein (VLDL) fraction. Intralipid, an artificial chylomicron emulsion, or isolated VLDL could extract o,p'-DDD from the other serum (lipo)proteins. There was an inverse relationship between the relative amount of o,p'-DDD found in the fraction exhibiting a density of less than 1.006 g/ml (chylomicrons plus VLDL) and the relative amount observed in the LDL or HDL fractions of serum. Our results indicate that hypertriglyceridemia may impede the entry of o,p'-DDD into the brain or the adrenals. For therapeutic monitoring of o,p'-DDD levels in severe hypertriglyceridemia, we recommend that the chylomicron and VLDL fraction first be removed from the serum by ultracentrifugation.

In 3 patients with adrenocortical carcinoma the effects of long-term mitotane therapy on the serum levels of three hormone-binding globulins and vitamin D-binding protein were studied. Within the first month of treatment cortisol-binding globulin increased two to three times, in close correlation with sex hormone-binding globulin. The rises in thyroxine-binding globulin and vitamin D-binding protein were considerably less. Elevated cortisol-binding protein appeared to be associated with increased binding of cortisol, whereas the binding of thyroxine and vitamin D remained below normal. Binding proteins returned to normal in 2 patients within a year after mitotane discontinuation. This phenomenon of hormone-binding protein enhancement invalidates the use of total serum hormone levels to monitor the effects of mitotane on endocrine function and could provide an explanation for the increased cortisol substitution requirement during mitotane therapy.

After finding prolonged bleeding times in 2 patients treated with mitotane, we prospectively studied 7 patients with adrenocortical cancer on mitotane therapy. Before and 1 and 2 or more weeks after starting mitotane we determined the platelet counts, bleeding times and global coagulation parameters. All patients had a normal bleeding time before treatment. In 6 cases the bleeding time became prolonged (245-555 s). 4 patients exhibited platelet aggregation responses compatible with an aspirin-like defect. It is concluded that mitotane may cause a clinically relevant defect of platelet function.

Thirty-four patients with adrenocortical carcinoma were treated with o,p'-DDD. Twenty-eight patients presented with metastases at entry, and spillage of tumour cells occurred at surgery in 6 other patients. Eight patients had objective tumour regression, of whom 7 had serum levels over 14 micrograms/ml. The 3 patients with a lasting remission had levels of greater than 15, greater than 25, greater than 25 micrograms/ml respectively during prolonged periods. Increased survival times were found in the group of 14 patients with o,p'-DDD serum levels higher than 14 micrograms/ml when compared with patients not treated after discovery of metastases. In the patients with levels less than or equal to 10 micrograms/ml no therapeutic effect was seen. Levels of over 20 micrograms/ml are associated with symptoms of reversible neuromuscular toxicity. Monitoring of serum levels during treatment is mandatory. It is suggested that serum levels of about 25 micrograms/ml during longer periods may be curative.

The distribution of o,p'-DDD in various body compartments of patients being treated for metastatic adrenocortical carcinoma was studied. A highly significant semilogarithmic relationship was found between plasma and adipose tissue concentrations during therapy and between plasma and brain at autopsy. A linear relationship was found at autopsy between concentrations in adipose tissue and those in various other tissues, such as tumour and brain. The semilogarithmic relationship can be explained by the assumption of two plasma pools for o,p'-DDD, one with low affinity and high capacity and one with high affinity and low capacity. Plasma concentrations must be carefully monitored to obtain an impression of the tumour concentration and to detect impending central nervous system intoxication.

Plasma levels of o,p'-DDD were measured after ingestion of a single oral dose. At the onset of therapy o,p'-DDD was administered as commercially available tablets and granules and in milk, chocolate, and an oil emulsion to 9, 12, 14, 10, and 6 patients, respectively. Following administration in chocolate, emulsion, and milk significantly higher mean plasma levels were recorded in the first 5- and 10-h periods than after tablets. Granules gave significantly lower plasma levels than all other forms. Plasma levels were also measured during maintenance therapy, when a total of 200 g o,p'-DDD was administered to 22 patients with adrenocortical carcinoma. The plasma disappearance rate after termination of long-term therapy was found to be between 18 and 159 days. The recovery of o,p'-DDD from faeces was about five times higher after ingestion of tablets than after administration in oil emulsion and milk. As far as the rapid increase in plasma levels and patient compliance are concerned, the best results were obtained with the milk powder mixture.