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Biomedical subjects

A Dupont

Publications and source records attributed to A Dupont.

At least 109 records · Page 6Linked to original sources
PubMed1987

Combination therapy in stage C and D prostatic cancer: rationale and five year clinical experience.

In 1941, Huggins and his colleagues discovered that testicular androgens exert a stimulatory effect on prostate cancer growth. Our group has made the key observations that the human adrenals, in addition to the tests, also secrete important amounts of androgens and cancer cells exhibit a marked heterogeneity of androgen sensitivity. In fact, human adrenals secrete large amounts of precursor steroids that are converted into active androgens in peripheral tissues (including the prostate), thus providing 40% to 50% of total androgens in adult men. The action of these androgens remaining after castration can be inhibited in prostatic cancer tissue by administering a pure antiandrogen that also decreases the local concentration of dihydrotestosterone (DHT). The castration levels of serum testosterone left in men after castration have an important stimulatory activity on the growth of androgen-sensitive normal as well as cancer tissues. Cancer cells have markedly different requirements for androgens. Some cell clones can grow in the presence of minimal amounts of androgens, requiring more complete androgen blockade and more potent antiandrogens for inhibiting growth. Among the compounds recommended as antiandrogens, the most unexpected finding is that many of them are devoid of any antiandrogenic activity. In fact, medroxyprogesterone acetate, chlormadinone acetate, and megestrol acetate have androgenic activity, but do not inhibit the peripheral action of DHT in prostatic tissue. These compounds should not be classified as antiandrogens. Cyproterone acetate, on the other hand, is a mixed agonist-antagonist. The only compounds showing pure antiandrogenic activity are Flutamide and its analogues. There is thus a need for a more complete blockade of androgens of both testicular and adrenal origins in order to exert a maximal inhibitory effect on cancer growth. We have therefore performed clinical studies in previously untreated stage D2 and C prostate cancer patients with the combination therapy using the LHRH agonist [D-Trp6, des Gly NH2(10)] LHRH ethylamide and the antiandrogen Flutamide. There was a significant increase in patients with a complete response, as compared with studies limited to the removal or blockade of testicular androgens. There was also a significant decrease in the number of non-responders, an increased duration of positive response, and a decrease in the death rate. This was achieved with minimal or no side effects, thus preserving a good quality of life.

Adrenal Glands↗
PubMed1987

Combination therapy with flutamide and castration (orchiectomy or LHRH agonist): the minimal endocrine therapy in both untreated and previously treated patients.

Patients (154) with clinical stage D2 prostate cancer with no previous endocrine therapy or chemotherapy received the combination therapy with the pure antiandrogen Flutamide and the LHRH agonist [D-Trp6]LHRH ethylamide for an average of 22 months (3-49 months). The objective response to the treatment was assessed according to the criteria of the US NPCP. There was a 6.3-fold increase (29.2 vs 4.6%) in the percentage of patients who achieved a complete response as compared to the results achieved in five recent studies limited to removal (orchiectomy) or blockade (DES or Leuprolide) of testicular androgens. Only 4.5% of patients did not respond to the combination therapy as compared to an average of 18% by standard therapy. The duration of response is also significantly increased in the patients who received the combination therapy. The death rate was decreased by approximately 2-fold between 2 and 3 yr of treatment. The marked (6.3-fold) improvement in the rate of complete objective responses coupled with the 4-fold decrease in the number of non-responders, the increased duration of the positive responses and the 2-fold decrease in the death rate at 2-3 yr of treatment are obtained with the combination therapy using Flutamide and castration with no or minimal secondary effects.

Adenocarcinoma↗
PubMed1987

Effects of flutamide and aminoglutethimide on plasma 5 alpha-reduced steroid glucuronide concentrations in castrated patients with cancer of the prostate.

Plasma levels of androstane-3 alpha, 17 beta-diol glucuronide (3 alpha-diol-G) and androsterone glucuronide (ADT-G) have been found to be effective markers of C-19 steroid metabolism in periphery in man. The present study has been performed in order to study in castrated patients the effect of antiandrogen administered alone or in combination with aminoglutethimide (AG) on the metabolism of adrenal C-19 steroid. Ten castrated patients with prostatic cancer received flutamide (FLU) alone for 2 months and, afterwards, the combined therapy of FLU and AG for 2 months. Antiandrogen treatment alone reduces the levels of dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone glucuronide (DHEA-G) and androstenedione (4-ene-dione) by 43, 34 and 38% (P less than or equal to 0.01) respectively while dehydroepiandrosterone (DHEA), androst-5-ene-3 beta,17 beta-diol (5-ene-diol) and androst-5-ene-3 beta,17 beta-diol-glucuronide (5-ene-diol-G) levels show a nonsignificant inhibition. In these patients, plasma 3 alpha-diol-G and ADT-G concentrations are nonsignificantly stimulated to 122 and 143%. Moreover, when patients were receiving the combined administration of FLU and AG, adrenal C-19 steroids were further inhibited while both 3 alpha-diol-G and ADT-G show a small but nonsignificant decrease. Our data indicate that the antiandrogen increases the formation and/or the metabolism of adrenal C-19 steroids into steroid glucuronides.

Aged↗
PubMed1987

Increase in plasma high-density lipoprotein concentration following complete androgen blockage in men with prostatic carcinoma.

There is evidence that endogenous estrogens have a positive effect on plasma high density lipoprotein (HDL) concentration, whereas the relation between HDL and male sex hormones is unclear, since both positive and negative effects have been reported. This study examined the effects of LHRH agonist in combination with an antiandrogen on plasma lipids and lipoproteins in 17 elderly men with prostatic carcinoma. Subjects were examined prior to and after therapy at 4-week intervals up to 16 weeks. Prior to therapy, their lipid and lipoprotein profiles were not significantly different from a control group composed of individuals of similar age and living in the same community area. Following therapy plasma levels of testosterone and dihydrotestosterone were markedly decreased (above 90%) and their residual activity neutralized through effective use of an antiandrogen. Plasma estradiol decreased between 65% and 85% and the concentration of cortisol was unaffected. The very low density lipoprotein (VLDL) apo-B decreased and low density lipoprotein (LDL) apo-B increased; thus, no change was observed in the total plasma apo-B levels. Total plasma cholesterol increased by 6% (baseline v peak values, mg/dL, mean +/- SEM; 219 +/- 9 v 233 +/- 9, P less than 0.05) due to a significant rise in HDL cholesterol concentration (45.5 +/- 2.8 v 56.5 +/- 3.6, P less than 0.01). Both VLDL and LDL cholesterol levels remained unchanged. The mean elevation of 21% in HDL cholesterol was accompanied by a significant rise in HDL apo-A concentration (161 +/- 6 v 193 +/- 10, P less than 0.01), thus suggesting an increase in HDL mass and/or particle number.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1987

Flutamide eliminates the risk of disease flare in prostatic cancer patients treated with a luteinizing hormone-releasing hormone agonist.

Although chronic treatment with luteinizing hormone-releasing hormone agonists achieves castration levels without side effects other than those related to hypoandrogenism, a limitation to their use alone for the treatment of prostatic cancer is the transient increase in serum androgens that lasts for 5 to 8 days at the start of treatment with the risk of disease flare. Our data show that the concomitant administration of the pure antiandrogen flutamide in association with the luteinizing hormone-releasing hormone agonist (D-Trp6) luteinizing hormone-releasing hormone ethylamide caused a 64 to 78 per cent decrease in serum prostatic acid phosphatase on days 3 and 7 after the start of treatment in 70 patients with previously untreated stage D2 prostatic cancer. Pain, which was present in 41 patients at the start of treatment, did not increase in any patient, it decreased in 7 at 1 week and it disappeared or decreased in 27 at 2 weeks. Performance, which originally was abnormal in 34 patients, became normal in 7 within 1 week and in 20 within 1 month (59 per cent). These data show that the addition of flutamide completely eliminates the risks of disease flare associated with the use of the otherwise exceptionally well tolerated luteinizing hormone-releasing hormone agonists in patients treated for prostatic cancer.

Acid Phosphatase↗
PubMed1987

Rett syndrome.

A Case of Rett syndrome in a 20-year old female patient in a mental retardation institution is described. Clinically and according to the case history she is very typical for the syndrome, and the different stages, the etiological theories and some efforts in order to find etiological factors are surveyed.

Adult↗
PubMed1987

Mortality, life expectancy and causes of death of mildly mentally retarded in Denmark.

Based upon the nationwide Danish registration, all cases with ICD 8 diagnoses 310 and 311 were drawn; 71% lived outside institutions. 7,134 persons were studied for the period 1 January 1976-3 March 1984 and examined in the central register for death, emigration, etc. 5.86%, 446 died during the observation period from 1 January 1976 to 31 March 1984. Mortality tables show estimated survival probability at the end of the 5-year intervals and the life expectancy at the start of the age intervals. Only small differences were found when comparing differences of mortality for sex and residence (institutions or outside institutions). By a linkage study with the Danish Central Register for causes of death in the National Health Service of Denmark, the causes of death were obtained. For males of the age 15-64 an excess mortality of malignant neoplasms, of diseases of the respiratory system, of congenital malformations, and of accidents were found. For females the pattern was less significant.

Abnormalities, Multiple↗
PubMed1987

[Toxoplasmosis in pregnant women in Haut Ogooué Province (Gabon)].

Anti-toxoplasma antibodies have been studied in 268 pregnant women. Two serological tests have been used: direct agglutination, before and after treatment with 2-mercaptoethanol, and indirect immunofluorescence. Agreement between the tests is over 98%. 60.5% of women have anti-toxoplasma antibodies at first examination. This percentage remains unchanged during pregnancy. Two cases of evolving toxoplasmosis have been observed. The mode of infection in Gabon is discussed.

Adult↗
PubMed1986

Advantages of the combination therapy in previously untreated and treated patients with advanced prostate cancer.

In order to achieve a more complete blockade of androgens of both testicular and adrenal origin at the start of treatment, we have administered the pure antiandrogen Flutamide in association with orchiectomy (13 patients) or the LHRH agonist [D-Trp6]LHRH ethylamide (118 patients) to previously untreated patients with clinical stage D2 prostate cancer. The mean duration of treatment was 491 days (102-1208 days). The response was assessed according to the criteria of the U.S. National Prostatic Cancer Project. A complete response has been observed in 30 patients (23%) while partial and stable responses have been achieved in 50 (38%0 and 45 (34%) patients, respectively. A positive objective response has thus been observed in 125 of 131 patients (95%). Serum PAP became normal before 6 months in all except 8 (6.1%) of patients. Quite remarkably, 23 of 48 patients treated for 2 years (47.9%) have achieved a complete response. Of the 20 deaths, 12 (9%) were due to prostate cancer, while 8 (6%) resulted from other causes. The probability of continuing a positive response after 2 years of treatment (according to Kaplan and Meier) is 60% while the probability of survival at the same time interval is 89%. This survival should be compared to values of approx 50% achieved with previous treatments limited to inhibition of testicular androgen secretion or action. The present data demonstrate that the combined blockade of androgens achieved with Flutamide and castration provides an objective response in approx 95% of patients, and markedly prolongs the period of remission while the death rate within the first 2 years is lower than that obtained with previous treatments. The important prolongation of survival is achieved with an excellent quality of life. Two-hundred and three patients have clinical stage D2 prostate cancer previously treated by orchiectomy, estrogens or LHRH agonists alone received, at the time of relapse, the same combination therapy. Patients already castrated received only Flutamide while, for those previously treated with DES, the estrogen was replaced by the LHRH agonist [D-Trp6]LHRH ethylamide in association with Flutamide. Flutamide was given as additional medication to those already receiving an LHRH agonist alone. Complete, partial and stable objective responses assessed according to the criteria of the U.S. National Prostatic Cancer Project were obtained in 11 (5.4%), 17 (8.4%) and 38 (18.7%) patients, respectively, for a total objective response rate of 32.5%. Progression continued in 137 (67.5%) patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Androgen Antagonists↗