I have serous cell endometrial cancer stage 3C. Have been on Enhertu for 1.5 years. Currently NED but treatment continues every three weeks until this therapy fails to work and the cancer returns. It's an inconvenient regime, entailing travel to the clinic (by plane) regularly. This is one of the main causes for my fatigue. Other symptoms are nausea, slight skin rash, hair loss - everywhere, peripheral neuropathy. Before this treatment was given platinum chemo but the it didn't work so well. The cancer returned 4 months later. The Enhertu works because I'm HER 3 positive 2+.