EFFICACY  OF  PREVENTIVE  PROSTAGLANDIN  TREATMENT  OF  MAMMARY  LESIONS,  IN  RATS:  AN  EXPERIMENTAL  TRIAL
 
        The aim of the study was to assess the efficacy of the preventive prostaglandin (PG) treatment in prevention of spontaneous tumors of mammary glands and other organs of female reproductive and related systems in small animals by creating a controlled environment to the laboratory animals which would reflect the actual exposure in the development of breast tumors in human females, with no extraneous, chemical, toxicological, hormonal or physical factors; to test the postulated cause-and-effect relation of the lack of seminal factors, presumably the Prostaglandins, in the tumorigenesis of mammary glands and other reproductive organs in female rats; to quantify the neoplastic effects in the female rats, exposed to six different reproductive conditions, and treatment and control procedures; and to test a set of 15 defined, interrelated hypotheses. An extended control-group time-series laboratory experiment on Wistar rats was performed. A colony of 300 female and 110 male animals, randomly allocated into six groups of 50 females, and housed together with 18 male animals of controlled and differentiated reproductive capacity. The tumorigenesis in the female rats was induced by sterile mating with vasectomized male animals only. Females were exposed to different reproductive potentials, such as male and female sterility, normal pregnancy, pseudopregnancy, preventive treatment with Prostaglandins of two-level dosage regimen, and a PG-vehicle, placebo maneuver. The observation period lasted one year. Spontaneous neoplastic lesions, palpable and histopathologically evaluated after sacrifice of the animals, carried out by two qualified ratters (histopathologists), in aggregates and incidence rates, of the target organs: mammary glands, ovaries, uterus, thyroid, adrenals, pituitary. Two hundred and nineteen female rats, out of the 296, survived the 13 months of observation. The first palpable mammary nodules were found in females exposed to vasectomized males (Group 1) in less than one month. The incidence of histopathologically confirmed mammary lesions was highest in this vesectomy-exposed female rats, with a rate of 89.5 percent, followed by the incidence in the PG-vehicle, placebo-treated female rats (Group 6), with a rate of 57.6%. Several cases of inordinate, circling, fatal conditions, first occurring in the 3rd month of observation, were observed in female rats of groups (1) and (6), with an estimated 7% incidence rate of the condition. The lowest incidence of mammary lesions, 18.9%, was found in the PG-treated females (of Groups 4 and 5), as expected, along with the incidence of 20.7% in fertile females of the control group exposed to intact males (Group 2) and an incidence of 32.3% in the infertile, tubo-ligated females exposed to intact males (Group 3). The differences to the baseline Group 1 were statistically significant (p<.0001). The ovarian and uterine lesions reached the highest incidence of almost 100% in the vasectomy-exposed group. The lowest incidence of pelvic lesions was found in the control animals (Group 2), exposed to perpetuate pregnancies, multiple deliveries, and 21-day breast-feedings. No dose-effect relation was found in the PG preventive interventions on any lesions. The Kappa value showed fair to good agreement beyond chance between the two ratters for the mammary lesions. The results of the experimental study supported the research hypothesis of a preventive potential of certain seminal factors, the Prostaglandins, against the development of neoplastic lesions in mammary glands and other reproductive and endocrine organs, in small animals. The efficacy of the PG-treatment was estimated at 73.7% in the prevention of mammary lesions (p<.0001). The efficacy of the preventive PG treatment was found to exhibit significant preventive effects on ovarian (45%) and thyroid lesions (90%) as well.
 

Present address:
        Arne N. Gjorgov, M.D., Ph.D.,
        MEDICS Group,
        G. Hadzi-Panzov Street, No. 2,
        Skopje,
        Republic of Macedonia.

Phone & fax:
       +389-91-127 361.
 
 
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