Hi there,
thought I'd chime in. I have IIIC1 (maybe 2, now) serous cell uterine cancer. Was diagnosed in June 2023. Underwent Carbo/pacil --6 rounds. Cancer metastasized in to pelvic and para-aorta lymph nodes. Had one month of Letrozole (hormone therapy drug), to see if it might shrink tumor. It didn't do a thing. Went off of that, and after a multitude of CT scans, and PET and MRI scans, the cancer showed it had spread and original lesion had grown. All this to say that the Carbo/pacil didn't work for me, in my case, hormonal therapy was a waste of precious time. I'm what you'd call, platinum-resistant. The doctor didn't say this to me; I looked it up, as with almost everything else. AS for Letrozole, it has only a 9% efficacy rate.
I have had no other systemic treatment since then. Just had a short, one-time burst of radiation to relieve pain and bleeding coming from a new, substantially large lesion in pelvis. Hasn't done anything. Now I'm waiting for participate in a clinical study using Enhertu, a targeted treatment using trastuzumab + deruxtecan (T-DXd). Trastuzumab is the clinical name for Herceptin.
All this to say that Herceptin is being used with other chemo drugs, in my case, deruxtecan, which have prove to be successful in extending PFS and OS for cancer patients with HER2 positive IHC3+, especially, and IHC2+ moderately. I am IHC2+.
Fingers crossed.
You might consider inquiring about the T-DXd for yourself.
Best of luck and know that you're not alone in all this.