Interview
with Neil Love, MD Breast Cancer Update for Medical Oncologists,
Program 6 2000
Play
Audio Below:
Tamoxifen
can cause cancer in the endometrium, but it can prevent cancer in
the opposite breast. And the number of new cancers that it prevents
is greater than the number of new cancers that it causes. So, its
net effect in terms of new cancers is to prevent, rather than to
cause. But it definitely can cause cancer of the endometrium. Most
of those endometrial cancers don’t cause death, but some do.
The total risk of death from the side effects of tamoxifen is about
3 per 1,000. If you give five years of tamoxifen, then the risk
that those five years of tamoxifen will actually cause death from
endometrial cancer or pulmonary embolus is about 3 per 1,000. But,
the probability that those five years of tamoxifen will prevent
death is more like about 90 per 1,000. So, in terms of life and
death, tamoxifen does 30 times more good than harm for a woman with
ER+ disease. If you’ve got very low-risk ER+ disease, it’s
still going to be doing quite a lot more good than harm.
Now,
these contralateral cancers — the cancers in the opposite breast
that are being prevented while you’re giving tamoxifen —
it’s approximately halving the incidence of cancer in the opposite
breast if you give five years of tamoxifen. And even in the years
after you stop your five years of tamoxifen, there’s a carryover
benefit. You still have a somewhat lower incidence rate of contralateral
breast cancer. You never get to a situation where the incidence
of contralateral breast cancer is greater in those who’d received
tamoxifen than in those who didn’t. So, there’s no evidence
of any overshoot. You get prevention, and then the rates stay either
lower or eventually, perhaps, they become parallel at around 15
years. We don’t have enough data beyond there, but it does
seem as though you’re actually reducing the number that are
ever going to arise, of cancers in the opposite breasts.
Relevant
Articles:
Selective
estrogen receptor modulators: Structure, function, and clinical
use [Review]. Osborne,
C. K. and Fuqua, S. A. W. Journal of Clinical Oncology. 18(17):3172-3186,
2000 Sep.
Similarities
and distinctions in the mode of action of different classes of antioestrogens
[Review]. Wakeling,
A. E. Endocrine-Related Cancer. 7(1):17-28, 2000 Mar. No abstract
Approaches
targeted to estrogen receptors for treatment of tamoxifen-resistant
breast cancer: A brief overview. Terakawa, N. (Reprint available from: Terakawa N Tottori Univ,
Sch Med, Dept Obstet & Gynecol Yonago Tottori 683 Japan)..
Oncology. 59(Suppl 1):3-4, 2000. No abstract
Preliminary
assessment of cognitive function in breast cancer patients treated
with tamoxifen. Paganini-Hill,
A. and Clark, L. J. Breast Cancer Res.earch & Treatment. 64(2):165-176,
2000 Nov.
Symposium
overview: Estrogens and antiestrogens in managing the patient with
breast cancer. Newman,
L. A.; Wood, W. C.; Sellin, R. V.; Morrow, M.; Vogel, C., and Singletary,
S. E. (Reprint available from: Singletary SE Univ Texas, MD Anderson
Canc Ctr, Dept Surg Oncol 1515 Holcombe Blvd,Box 106 Houston, TX
77030 USA).. Annals of Surgical Oncology. 7(8):568-574, 2000 Sep.
In process
The
ovary: cysts, screening, and tamoxifen. Mourits,
M. J. E.; van der Zee, A. G. J.; Willemse, P. H. B., and de Vries,
E. G. E. (Reprint available from: de Vries EGE Univ Groningen Hosp,
Dept Med Oncol POB 30 001 NL-9700 RB Groningen Netherlands). Lancet.
355(9220):2078-2079, 2000 Jun 10.
Concentrations
of tamoxifen and its major metabolites in hormone
responsive and resistant breast tumours. MacCallum, J.; Cummings, J.; Dixon, J. M., and Miller, W. R.
(Reprint available from: MacCallum J Napier Univ, Dept Life Sci
Merchiston Campus,Colinton Rd Edinburgh EH10 5DT Midlothian Scotland)..
British Journal of Cancer. 82(10):1629-1635, 2000 May.
How
is tamoxifen's action subverted? Jordan, V. C. (Reprint available from: Jordan VC Northwestern
Univ, Sch Med, Rober H Lurie Comprehens Canc Ctr 303 E Chicago Ave,Olson
Pavil 8258 Chicago, IL 60611 USA). Journal of the National Cancer
Institute. 92(2):92-94, 2000 Jan 19. No abstract
Serum
lipid levels during and after adjuvant toremifene or tamoxifen therapy
for breast cancer. Joensuu, H.; Holli, K.; Oksanen, H., and Valavaara, R. (Reprint
available from: Joensuu H Univ Helsinki, Cent Hosp, Dept Oncol Haartmaninkatu
4,POB 180 FIN-00029 Helsinki Finland). Breast Cancer Research &
Treatment. 63(3):225-234, 2000 Oct. In process
One
step forward or one step back with tamoxifen? Gelmon, K. (Reprint available from: Gelmon K British Columbia
Canc Agcy Vancouver BC V5Z 4E6 Canada). Lancet. 356(9233):868-869,
2000 Sep 9. No abstract
Endometrial
protection from tamoxifen-stimulated changes by a evonorgestrel-releasing
intrauterine system: a randomised controlled trial. Gardner, F. J. E.; Konje, J. C.; Abrams, K. R.; Brown, L. J.
R.; Khanna, S.; Al-Azzawi, F.; Bell, S. C., and Taylor, D. J.. Lancet.
356(9243):1711-1717, 2000 Nov 18. No abstract
Combined
endocrine therapy for breast cancer - New life for an old idea? Davidson, N. E. (Reprint available from: Davidson NE Johns Hopkins
Oncol Ctr 1650 Orleans St, Rm 409 Baltimore, MD 21231 USA). Journal
of the National Cancer Institute. 92(11):859-860, 2000 Jun 7. No
abstract
Risk
and prognosis of endometrial cancer after tamoxifen for breast cancer. Bergman, L.; Beelen, M. L. R.; Gallee, M. P. W.; Hollema, H.;
Benraadt, J., and van LeeuwenF. E.. Lancet. 356(9233):881-887, 2000
Sep 9. IN PROCESS
