Another lump

Here’s the thing: I have this lump on my finger that appeared one morning about a month ago. It’s raised, about 1×2 cm, on the proximal phalanx of my left second finger. It’s hard, smooth, and it hasn’t gotten bigger in the last month.
I went to the doctor and he said, “I don’t know what it is either.” He ordered an Xray, which just showed arthritis in the base of my thumb. No calcifications in the lump, which is just barely visible as a soft tissue shadow.
So he sent me to a hand surgeon. I haven’t seen him yet.
Eventually, someone is going to have to cut it off and look at it under the microscope.
It doesn’t act like a malignant tumor; it’s not growing nor painful.
Just one more consequence of having turned 70 years old on April 26.