Nexus - 0504 - New Times Magazine-pages

Page Content (OCR)

TAMOXIFEN A Major Medical Mistake? TAMOXIFEN Medical Mistake? Major Once praised for its benefits in preventing breast cancer recurrence, the lucrative pharmaceutical drug tamoxifen ts now implicated in causing dangerous side-effects including other types of cancers. n the early 1970s, a shameful chapter closed on the widespread use of a known car- cinogenic and endocrine-disrupting drug called DES (diethylstilboestrol), the first synthetic, non-steroidal oestrogen drug. Against the advice of its creator, Sir Charles Dodd, between four and six million American and European women and 10,000 Australian women innocently used DES for the prevention of miscarriage and pregnancy complications. In addition, DES became a popular though unproven drug for a variety of other condi- tions. It was used for the suppression of lactation, the treatment of acne, the treatment of certain types of breast and prostatic cancer, and as an inhibitor of growth in young girls, an oestrogen replacement in menopause and a "morning after" pill. It would take 30 years to accept what laboratory tests had indicated as early as 1938— that DES was a highly dangerous and harmful drug. It was reported that, 20 years after taking DES, mothers had a 40 to 50 per cent greater risk of breast cancer than non- exposed mothers. In addition, the children of DES mothers showed a high incidence of reproductive abnormalities, miscarriages, vaginal cancer, testicular cancer, sterility and immune dysfunction. In fact, it is feared that repercussions of this drug will be felt for generations to come. The irony of this entire debacle is that the medical establishment finally acknowledged that DES was useless in preventing miscarriages. Thus, DES, another disastrous experi- ment on women, was added to the long list of major medical blunders. Out of this early research, a new drug appeared on the horizon which would be soon be heralded as a shining star in the war against the growing epidemic of breast cancer. In the late 1960s the pharmaceutical industry developed a drug called "tamoxifen". As a syn- thetic, non-steroidal compound with hormone-like effects (many of which are poorly understood), tamoxifen has a similar structure to DES. In fact, it was observed that tamoxifen caused the same abnormal changes seen in cells of women taking oestradiol and DES.' This similarity raised alarm bells for some. Pierre Blais, well known as a drug researcher who was ejected from Canada's health protection bureaucracy when he spoke out about silicone breast implants, describes the story of tamoxifen as "the story of modern drug design which produces garbage drugs". He says, "Good drug design ceased, unfortunately, in the 1930s." Tamoxifen, Blais is a garbage drug that made it to the top of the scrap heap. It is a DES in the making, Blais's dire predictions were ignored with the promise of a potential drug treatment for breast cancer. Tamoxifen was first approved by the US Food and Drug Administration (FDA) for use as a birth-control pill; however, it proved to induce rather than inhibit ovu- lation. Although tamoxifen didn't work as a contraceptive, it was found to lower mamma- ry cancer rates in animals. Animal studies showed that tamoxifen prevented oestrogen from binding to receptor sites on breast tissue cells. Tamoxifen also reduced the inci- dence of breast cancer in rodents after administration of a breast-carcinogenic substance. This discovery provided the impetus to study its effects in treating human breast cancer. Oestrogen is the common link between most breast cancer risk factors, i.e., genetic, reproductive, dietary, lifestyle and environmental. It both stimulates the division of breast cells (healthy as well as cancerous) and, especially in its 'bad' form, increases the risk of breast cancer. Thus, hormonal drugs such as tamoxifen that block the effects of oestrogen on the breast were expected to reduce the risk of breast cancer recurring in women treated for breast cancer.’ Tamoxifen acts as a weak oestrogen by competing for oestrogen receptors much as by Sherrill Sellman © 1998 Light Unlimited Productions Locked Bag 8000-MDC Kew, Victoria 3101, Australia Telephone: +61 (0)3 9249 9591 Fax: +61(0)3 9855 9991 E-mail: golight@netspace.net.au Light Unlimited Productions Locked Bag 8000-MDC Kew, Victoria 3101, Australia Telephone: +61 (0)3 9249 9591 Fax: +61(0)3 9855 9991 E-mail: golight@netspace.net.au JUNE - JULY 1998 NEXUS - 43 by Sherrill Sellman © 1998