For Breast Cancer Low-Dose Tamoxifen as Effective as Higher Doses
We did a phase three trial of low-dose Tamoxifen, which is an anti entered estrogen, to prevent recurrence within women, who had a non invasive breast cancer, which can be an atypical ductal hyperplasia, a nobuler or ductal carcinoma site. These forms are very common today with the introduction of screening mammography. At least 20% of all breast neoplasms are intrepid illionaire pleasure.
We found a 50% reduction in the recurrence in the low-dose Tamoxifen arm, compared with placebo, which is the same effect that we found in the past with 20 milligram, which is the standard dose. We used a 5 milligram dose per day, which is a lower dose, which is associated with fewer side-effects.
Our side effects with Tamoxifen typically are in the metro-cancer, deep vein thrombosis, menopausal symptoms, such as hot flashes, vaginal dryness, pain during intercourse and others. In this trial we showed a lowering of these serious adverse events. We just noted one case of stage 1 endometrial cancer. We would predict nearly 3 with a full dose. And we saw one case each of venous thromboembolism, both in the Tamoxifen arm and the placebo arm, whereas we would predict 2.5 with the full dose.
Perhaps, more importantly, we saw no difference in menopausal symptoms. There was, in fact, a slight borderline significant increase in the number of hot flashes per day, which resulted in less than one extra hot flash per day, compared with placebo, no increase in the intensity of the hot flashes, and, perhaps, more importantly, there was no increase in pain during intercourse or vaginal dryness. Finally, we noted no increase in skeletal pain, which is frequently associated with aromatase inhibitors treatment.
We saw a very intriguing 75% reduction of contra-lateral breast cancer, which, of course, opens the doors for a primary prevention trial within healthy at-risk women, because, you know, the side effects of Tamoxifen have prevented its broad use in prevention, despite the strong evidence of efficacy by the side effects. Preclude its use we hope that with the lower dose more women will take this drug for primary prevention, especially, those women, who are at higher risk, including the women with Brock mutation.
That study was supported by Italian government and two charities: the Italian Association for cancer research and the Italian league against cancer. We are indebted to these institutions for supporting study aim at maintaining fair, equitable and affordable medicine.