Hi AlaskaAngel and Debbie,
I heard from my oncologist on the issue of testosterone safety and her message follows, so I hope it's helpful to you. It appears, from her reply, that it is more of a concern for ER+ women, and overall more studies need to be done. While I am ER-, I have decided not to fill my prescription due to this. btw, she gave you both a very nice compliment. Thanks again for contributing to this discussion, as it really helped me to think more clearly about it.
Your friend from So. Cal.,
Vicki
Vicki, Here is an article which may indirectly answer your question. Your friends make a very persuasive plea for further research on this. I would agree with them. Testosterone can inhibit or enhance tumor growth in preclinical models if you do pubmed search. Then this article relates to your question.
BACKGROUND: Levels of endogenous hormones have been associated with the risk of breast cancer among postmenopausal women. Little research, however, has investigated the association between hormone levels and tumor receptor status or invasive versus in situ tumor status. Nor has the relation between breast cancer risk and postmenopausal progesterone levels been investigated. We prospectively investigated these relations in a case-control study nested within the Nurses' Health Study. METHODS: Blood samples were prospectively collected during 1989 and 1990. Among eligible postmenopausal women, 322 cases of breast cancer (264 invasive, 41 in situ, 153 estrogen receptor [ER]-positive and progesterone receptor [PR]-positive [ER+/PR+], and 39 ER-negative and PR-negative [ER-/PR-] disease) were reported through June 30, 1998. For each case subject, two control subjects (n = 643) were matched on age and blood collection (by month and time of day). Endogenous hormone levels were measured in blood plasma. We used conditional and unconditional logistic regression analyses to assess associations and to control for established breast cancer risk factors. RESULTS: We observed a statistically significant direct association between breast cancer risk and the level of both estrogens and androgens, but we did not find any (by year) statistically significant associations between this risk and the level of progesterone or sex hormone binding globulin. When we restricted the analysis to case subjects with ER+/PR+ tumors and compared the highest with the lowest fourths of plasma hormone concentration, we observed an increased risk of breast cancer associated with estradiol (relative risk [RR] = 3.3, 95% confidence interval [CI] = 2.0 to 5.4), testosterone (RR = 2.0, 95% CI = 1.2 to 3.4), androstenedione (RR = 2.5, 95% CI = 1.4 to 4.3), and dehydroepiandrosterone sulfate (RR = 2.3, 95% CI = 1.3 to 4.1). In addition, all hormones tended to be associated most strongly with in situ disease. CONCLUSION: Circulating levels of sex steroid hormones may be most strongly associated with risk of ER+/PR+ breast tumors.
So my conclusion is testosterone is not safe in hormone receptor positive breast cancer, but should be subject of research in hormone receptor negative breast cancer.