I'd be interested in what paula21 and rainna have to say about their experiences with LenPem, too. I have Stage IV serous cell endometrial cancer, and have been given a choice between LenPem or participating in a clinical study to evaluate the efficacy and safety of trastuzumab deruxtecan (T-DXd) for the treatment of selected HER2-expressing tumors, which are usually present in a variety cancer types, including serous cell endometrial cancer. I've read the scientific literature on both treatments and see that both appear to have serious side effects. The T-DXd so far is hypothesized to "show meaningful clinical activity and a favorable risk benefit" (whatever that really means). No study results have been published, that I can find. My situation is that I must allow the cancer to grow to a size that qualify me to participate in the study. This makes me nervous, given that this is a study and no results have been published, and that LenPem has been the recommended treatment for treatment for late-stage endometrial cancer. This I can start on immediately. The choice is up to me:(