Hang tough brother, you got this. 💪
If you have not already done so, get involved with support groups. Chock-a-block with good advice.
https://www.cancercare.org/support_groups/tagged/mantle_cell_lymphoma
https://www.lls.org/support-resources/support-groups
We are the same age. Back at the turn of the century, I went through 6 months or so of tests and surgeries, grinding it out because it was strongly suspected I had Non-Hodgkin lymphoma. Went to my Doc because the lymph node under my chin felt like a walnut and I was waking up drenched in sweat. He went from his usual jovial bedside to super serial like flipping a switch, after the say AHHH part. Blood work results had him downright grim. He referred me to an ENT. He too got super serial just looking at my right tonsil and reading my files. CT, MRI, biopsies, exploratory throat surgery plus a tonsillectomy. Then further months of uncertainty before getting clear with the Oncologist.
I don't do the deities thing, but I am the power of positive thinking type. It was removing the malignant tonsil that saved my ass. But I choose to gaslight myself that focusing my mental energy on destroying my adversary, including visualization, and being indefatigably positive the whole time, helped with the positive outcome.
I'll 🍾one for you to help celebrate after you have beat MCL by KTFO.