An unusual type of endometrial cancer, related to tamoxifen?

Tamoxifen, which is increasingly being used in breast cancer patients, has been associated with an elevated frequency of endometrial carcinoma. To our knowledge not a single case of uterine serous papillary carcinoma (USPC) has been documented during tamoxifen treatment. No conclusions as to a causal relationship are yet being made, but if it is due to tamoxifen, we should advise a strategy for prevention, because this subtype is not as curable as endometrioid carcinoma.

Time-related interference of misoprostol with experimental gastric cancer formation induced by N-methyl-N'-nitro-N-nitrosoguanidine in the rat.

The purpose of this study was to investigate the effect of long-term misoprostol administration, at non-antisecretory doses, on N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)-induced gastric carcinogenesis. The incidence of gastric carcinomas and precancerous lesions was evaluated in 50 male 250-g Sprague-Dawley rats after 52 weeks of continuous oral administration of MNNG (120 mg/l; n = 20), MNNG plus misoprostol (2 mg kg-1 day-1; n = 20) or tap water (n = 10) (experiment 1), and in 30 rats treated with MNNG for 30 weeks followed by tap water (n = 15) or by misoprostol (n = 15) for 22 weeks; a third group (n = 10) received tap water only for 52 weeks (experiment 2). After sacrifice, gastric mucosal lesions were macroscopically evaluated and their histology obtained. MNNG consumption was comparable in all groups (6.5 +/- 1.1 mg rat-1 day-1). Misoprostol consumption was 180 +/- 0.25 mg kg-1 day-1 rat-1. In experiment 1 the incidence of gastric carcinomas was 60% in the MNNG group and 25% in the group treated with MNNG plus misoprostol (P less than 0.05). Cytotoxic and hyperplastic gastric mucosal lesions were also significantly reduced by misoprostol. In experiment 2 the incidence of carcinomas was 31% and 38.6% respectively. Misoprostol significantly decreased the incidence of gastric cancer formation when given from the beginning of the experiment. By contrast, when administered after 30 weeks of MNNG treatment it did not interfere with experimental gastric cancer formation. Exogenous prostaglandins are able to prevent the early MNNG-induced gastric mucosal lesions, thus interfering with gastric carcinogenesis.

[1,2-dimethylhydrazine induction of epithelial tumors of the kidneys in CBA strain mice]. / Induktsiia 1,2-dimetilgidrazinom épitelial'nykh opukholei pochek u myshei linii CBA.

The results of experiments on the 1,2-dimethylhydrazine (DMH) induction of epithelial renal tumours in CBA male mice are presented. The dose-response study shows a sharp increase (from 5 to 75%) of the epithelial renal tumour incidence in the range of 2, 4 and 8 injections of DMH. Higher doses induce a decrease of the tumour incidence due to the early death caused by other tumours. DMH is shown to be the most powerful renal carcinogen in mice. Serial sacrifice of mice after 5 injections of DMH is a convenient model for the study of renal carcinogenesis in mice. Main histological types of epithelial renal tumours are illustrated.

Ovarian cancer in women given diethylstilboestrol in pregnancy: two case reports.

Two cases of ovarian cancer that developed many years after exposure to large dozes of diethylstilboestrol during pregnancy are reported. This paper is the first such cases reported.

Tumors of female offspring of mice exposed prenatally to diethylstilbestrol.

Strain CD-1 female mice exposed prenatally to diethylstilbestrol (DES) (CAS: 56-53-1; alpha,alpha'-diethyl-4,4'-stilbenediol) were mated to unexposed males. Female offspring of these matings were raised to the stage of terminal illness. They were never exposed to DES and so have been referred to as "DES-lineage mice." Ten uterine adenocarcinomas and 5 ovarian cystadenocarcinomas were found in 40 DES-lineage mice. These findings were significantly different from the absence of such tumors in 24 "vehicle-lineage" mice whose mothers had received injections only of oil and alcohol. The types of tumors that commonly occur spontaneously in the CD-1 strain appeared with comparable frequency in the 2 groups of mice. The DES-lineage mice did not show the increased frequency of adenomyosis and squamous metaplasia of the uterus, nor the reduced frequency of corpora lutea seen in mice exposed prenatally to DES.

Effects of progesterone on mammary carcinogenesis when various doses of DMBA were applied directly to rat mammae.

To investigate the suggestion that progesterone acts directly on the mammary gland to inhibit carcinogenesis, doses of 500, 100 or 30 microgram of DMBA were applied directly to inguinal mammary glands of 50 d old rats which either received no other treatment or were injected with progesterone (3 mg/d) s.c. for 18 d before dusting the carcinogen. Progesterone pretreatment did not inhibit mammary carcinogenesis in rats dusted with 500 microgram or DMBA. When smaller doses of DMBA (100 microgram or less) were applied, hormone pretreatment markedly reduced carcinogenesis, the inhibitory effect being statistically significant in the group dusted with the smallest dose of carcinogen. As the dusting technique eliminated any observable systemic effects of the carcinogen, it is concluded that the results support the suggestion that progesterone acts directly on the mammary gland to inhibit carcinogenesis and that this effect can be over-ridden if a large enough dose of DMBA (somewhere between 100 and 500 micrograms) is applied. The importance of carcinogen dose to resulting tumour yield was clearly shown by the significant descending gradation in tumour incidences and gradual lengthening of average tumour latent periods in the 3 control groups with decreasing DMBA dose, as well as in the 3 hormone-pretreated groups.

Extrahepatic malignancy in chronic liver disease: report of six cases.

Six patients are described with chronic liver disease, 3 with primary biliary cirrhosis and 3 with chronic active hepatitis, all of whom developed malignant disease in organs other than the liver. Two malignancies were mixed histiocytic-lymphocytic lymphomas. All patients had received corticosteroid or azathioprine therapy. Specific lymphocyte counts and immunoglobulin and antibody determinations failed to reveal a consistent pattern of abnormality to recognize the patient at risk. Several diseases in which the immune responsiveness is disturbed seem to have this potentiality in common, especially if therapy that further alters immunological reactivity is given.