Would you consider hormone replacement therapy in young women with germline BRCA1 mutation and history of triple negative breast cancer who underwent bilateral mastectomy and prophylactic bilateral salpingo-oophorectomy?

There is inadequate data to clearly answer the question of safety of HRT after a diagnosis of breast cancer. A recent review by Ugras and Rahman summarized the published literature and concluded that the evidence does not suggest an increase in recurrence or death with the use of HRT in this setting (PMID 33508379).

I would probably support the use of HRT. Very early menopause increases the risk of premature death due to cardiovascular and bone events. This is an ER negative tumor so the theoretic concern about increased risk of recurrence is less of an issue. She has had bilateral mastectomy so risk of contralateral cancer is reduced. She could consider a hysterectomy at the time of BSO to eliminate the need for progestins.

One option would...

I agree with previous responses on this topic. Generally speaking, I would suggest alternative non-hormonal choices to treat menopausal symptoms in women with prior BC diagnosis. While initial observation studies were reassuring, the two Scandinavian RCTs (HABITS, STOCKHOLM) showed concern for increased cancer recurrence with the use of 2 years of menopausal hormone therapy (MHT) with no impact on BC mortality. MHT was given for 2 years either as combined E-P or estrogen alone in women with prior hysterectomy. Both trials were stopped early and as such are underpowered to assess overall survival. STOCKHOLM did not show an increase in recurrence-free survival after 10 years of median follow-up but contralateral BC rates were 2-3 times higher...