Merkel cell carcinoma

Hello,
I was diagnosed in 2019 with Myelofibrosis and had a stem cell transplant in November 2020. Lot's of activity surrounding that! Developed GVHD one year later with a red rash over my entire body and a cough that lasted a year. Last April, 2024, I was diagnosed with MCC in my groin and abdomen (lymph nodes) I had surgery but now have a mass in my Duodenum. Keytruda infusion has started but I am experiencing severe bone pain, itching and rash. I am concerned the GVHD will be aggravated from this...