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NCAA News Archive - 2007
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Oncologist details antiestrogen ban
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By D. Lawrence Wickerham
The NCAA News
The NCAA News
The NCAA Committee on Competitive Safeguards and Medical Aspects of Sports has recommended, and the NCAA has approved, adding the drug class of “antiestrogens” to the list of banned substances, effective August 2007. This class of drugs has the potential for athletic performance enhancement. The following article provides an overview of the definition, clinical use and potential abuses of antiestrogens.
This fall, the NCAA will add antiestrogens, also known as aromatase inhibitors (AIs) and selective estrogen receptor modulators (SERMs), to the NCAA banned drug classes list. What are these drugs? How are they regularly used clinically? What are the potential abuses related to doping?
The following Q&A should help clarify the issue.
Q What are these drugs and how are they used medically?
A About 70 percent of all breast cancers require the female hormone estrogen to continue to grow. Both AIs and SERMs interrupt that estrogen-dependent cell growth.
Three third-generation selective aromatase inhibitors (with trademarked product names in parentheses) are available in the United States: anastrozole (Arimidex), letrozole (Femara) and exemestane (Aromasin). Aminoglutethimide is a first-generation AI that is infrequently used today because of its toxicities, which can be life-threatening.
The Food and Drug Administration (FDA) has approved anastrazole, letrozole and exemestane for use by postmenopausal women with breast cancer that responds to hormonal treatment. All three come in pill form and are taken once per day. These AIs block the production of estrogen, which in postmenopausal women occurs not in the ovary but rather through the conversion of adrenal androgens to estrogen. It is actually the enabling enzyme aromatase that is inactivated when AIs are used, which results in estrogen levels in the blood dropping to almost zero and thus halting breast cancer cell growth.
These drugs are excreted by the kidneys and have a half-life of about one to four days.
SERMs, which don’t block the production of estrogen but rather block the uptake of estrogen by cancer cells and some normal cells, are older agents. The most commonly used SERM is tamoxifen (Nolvadex), a pill that is used daily by both pre- and postmenopausal women with hormone-responsive breast cancer.
The FDA also has approved tamoxifen for the prevention of breast cancer in healthy women who are at increased risk for the disease based on their family history and other risk factors. Men account for less than 1 percent of all breast cancer cases, but most do respond to hormonal treatment and many receive tamoxifen as part of their treatment. Tamoxifen is only rarely used as a fertility pill or to reduce gynecologic symptoms in premenopausal women with endometriosis.
Raloxifene (Evista) is also a SERM, but it is not yet used to treat breast cancer. It is approved for the treatment and prevention of osteoporosis in postmenopausal women and has been shown, like tamoxifen, to reduce the risk of developing breast cancer in postmenopausal women who are at increased risk. FDA approval for this use is pending.
SERMs are used daily and are excreted primarily in the feces rather than the urine. Raloxifene has a half-life of two to three days and tamoxifen has a half-life of five to seven days.
Q Why would athletes use AIs or SERMs?
A The likely subgroup of athletes who might use AIs or SERMs are those athletes who have used or are using anabolic steroids. AIs and SERMs are being fallaciously promoted on various web sites for their purported “potential” to enhance athletic performance. Testimonials tout the idea that by lowering estrogen, both male and female athletes may “recover faster from hard workouts.”
The negative health effects of using anabolic androgenic steroids (AAS) are well-known. Both SERMs and AIs appear to reduce the estrogenic effects that occur with anabolic steroid use, including edema, gynecomastia (breast enlargement) and female fat distribution. In men, both SERMs and AIs also appear to increase testosterone levels modestly but are unlikely to result in any clinically apparent change with regard to that hormone. In addition, the data reflects the modest increase to have occurred in older men with other medical conditions, not likely typical of the intercollegiate athletic population.
The safety of these agents is largely untested in men. AIs, by reducing estrogen levels in basically healthy men, may have a deleterious impact on bone turnover as well as potential impact on the central nervous system, lipid metabolism, vascular physiology,and cardiovascular risk, dangers that are not counterbalanced in any way by disease treatment or prevention of disease. SERMs are known to increase the risk of major blood clots, which obviously can be life-threatening.
Raloxifene has been studied in very few premenopausal women and little is known about its safety in this group. Tamoxifen is relatively safe in younger women but there is some concern that it may cause birth defects.
Relatively few college-age athletes will use either SERMs or AIs for approved medical purposes. Less than 1 percent of breast cancers occur in women under age 30. Typically, tamoxifen is used for prevention purposes in women 35 or older. On occasion, tamoxifen could be used in a female in her 20s. However, a team physician or athletic trainer would be able to easily confirm the need for such medications and would then apply for an NCAA medical exception in those cases.
The NCAA’s decision to prohibit antiestrogens is a logical step to further reduce the use of substances that may be performance-enhancing or mask the side effects of those that are. More importantly, it will help to ensure the well-being of its student-athletes.
D. Lawrence Wickerham is a research oncologist with the National Surgical Adjuvant Breast and Bowel Project, an international cancer research group that has conducted several large cancer and prevention studies evaluating hormonal therapies.
This fall, the NCAA will add antiestrogens, also known as aromatase inhibitors (AIs) and selective estrogen receptor modulators (SERMs), to the NCAA banned drug classes list. What are these drugs? How are they regularly used clinically? What are the potential abuses related to doping?
The following Q&A should help clarify the issue.
Q What are these drugs and how are they used medically?
A About 70 percent of all breast cancers require the female hormone estrogen to continue to grow. Both AIs and SERMs interrupt that estrogen-dependent cell growth.
Three third-generation selective aromatase inhibitors (with trademarked product names in parentheses) are available in the United States: anastrozole (Arimidex), letrozole (Femara) and exemestane (Aromasin). Aminoglutethimide is a first-generation AI that is infrequently used today because of its toxicities, which can be life-threatening.
The Food and Drug Administration (FDA) has approved anastrazole, letrozole and exemestane for use by postmenopausal women with breast cancer that responds to hormonal treatment. All three come in pill form and are taken once per day. These AIs block the production of estrogen, which in postmenopausal women occurs not in the ovary but rather through the conversion of adrenal androgens to estrogen. It is actually the enabling enzyme aromatase that is inactivated when AIs are used, which results in estrogen levels in the blood dropping to almost zero and thus halting breast cancer cell growth.
These drugs are excreted by the kidneys and have a half-life of about one to four days.
SERMs, which don’t block the production of estrogen but rather block the uptake of estrogen by cancer cells and some normal cells, are older agents. The most commonly used SERM is tamoxifen (Nolvadex), a pill that is used daily by both pre- and postmenopausal women with hormone-responsive breast cancer.
The FDA also has approved tamoxifen for the prevention of breast cancer in healthy women who are at increased risk for the disease based on their family history and other risk factors. Men account for less than 1 percent of all breast cancer cases, but most do respond to hormonal treatment and many receive tamoxifen as part of their treatment. Tamoxifen is only rarely used as a fertility pill or to reduce gynecologic symptoms in premenopausal women with endometriosis.
Raloxifene (Evista) is also a SERM, but it is not yet used to treat breast cancer. It is approved for the treatment and prevention of osteoporosis in postmenopausal women and has been shown, like tamoxifen, to reduce the risk of developing breast cancer in postmenopausal women who are at increased risk. FDA approval for this use is pending.
SERMs are used daily and are excreted primarily in the feces rather than the urine. Raloxifene has a half-life of two to three days and tamoxifen has a half-life of five to seven days.
Q Why would athletes use AIs or SERMs?
A The likely subgroup of athletes who might use AIs or SERMs are those athletes who have used or are using anabolic steroids. AIs and SERMs are being fallaciously promoted on various web sites for their purported “potential” to enhance athletic performance. Testimonials tout the idea that by lowering estrogen, both male and female athletes may “recover faster from hard workouts.”
The negative health effects of using anabolic androgenic steroids (AAS) are well-known. Both SERMs and AIs appear to reduce the estrogenic effects that occur with anabolic steroid use, including edema, gynecomastia (breast enlargement) and female fat distribution. In men, both SERMs and AIs also appear to increase testosterone levels modestly but are unlikely to result in any clinically apparent change with regard to that hormone. In addition, the data reflects the modest increase to have occurred in older men with other medical conditions, not likely typical of the intercollegiate athletic population.
The safety of these agents is largely untested in men. AIs, by reducing estrogen levels in basically healthy men, may have a deleterious impact on bone turnover as well as potential impact on the central nervous system, lipid metabolism, vascular physiology,and cardiovascular risk, dangers that are not counterbalanced in any way by disease treatment or prevention of disease. SERMs are known to increase the risk of major blood clots, which obviously can be life-threatening.
Raloxifene has been studied in very few premenopausal women and little is known about its safety in this group. Tamoxifen is relatively safe in younger women but there is some concern that it may cause birth defects.
Relatively few college-age athletes will use either SERMs or AIs for approved medical purposes. Less than 1 percent of breast cancers occur in women under age 30. Typically, tamoxifen is used for prevention purposes in women 35 or older. On occasion, tamoxifen could be used in a female in her 20s. However, a team physician or athletic trainer would be able to easily confirm the need for such medications and would then apply for an NCAA medical exception in those cases.
The NCAA’s decision to prohibit antiestrogens is a logical step to further reduce the use of substances that may be performance-enhancing or mask the side effects of those that are. More importantly, it will help to ensure the well-being of its student-athletes.
D. Lawrence Wickerham is a research oncologist with the National Surgical Adjuvant Breast and Bowel Project, an international cancer research group that has conducted several large cancer and prevention studies evaluating hormonal therapies.
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