Again in this scenario, Its the Risk Vs Benefit Equation.
The Risk of recurrence in ipsilateral and contralateral breast of women who has taken Tamoxifen for 4 years Vs 5 years is small.
This lady had indeed a very small pT1c No Mo , favourable Breast cancer, so the benefits are miniscule. Cant quantify this risk currently, it will require quite a lot of digging up into trials.
On the other hand, you can very safely re-initiate Tamoxifen as in such pts benign causes of Vaginal bleeding are much more (10 times) common than sinister causes. Incidence of Vaginal bleeding with tamoxifen = 10%
Incidence of Endometrial cancer, in the Swedish Tamoxifen Trial where they used 40mg Tamoxifen Vs Placebo was 1.67%, while in the NSABP 14 trial, the incidence was 1.05% and usually from all the trials, these Tamoxifen induced endometrial cancers have a better prognosis as they are usually Stage 1 with an extremely rarely ever reported deaths from it.
Arimidex is ideal in this scenario, but you cant force a pt to pay.
All what you can discuss with this pt is Risks of re-initiating tamoxifen Vs Risks of Stopping Tamoxifen.
Usually clincal experience dictates that women dont like the thought of having heir breast cancer ever back even if its a small risk.
For some reason, they are happy to have a womb cancer, as they could have a hysterectomy for that.