Hello. About a month and a half ago I had dark blemish underneath my toenail on my left foot on the big toe.I went to the doctor and he said to watch it for a month and see if it moves. I didn't see any movement, so I went back and they sent me to a dermatologist.That was about 1.5 months ago. I have since went to the dermatologist, & I didn't detect any movement of it with the growth of the nail. The dermatologist examined it with a scope and thinks its a hematoma but wanted to get a biopsy performed anyhow just to be safe. Later that night I detected that there was very slight movement based on up-close photos I took from the beginning of this until present, with a mm ruler in each photo . Everything I have learned about it suggests that if it moves then it is not subungual melanoma. The disturbing part is that I didn't injure my toe that I know of, and I rarely get bruised . This seemed to happen for no reason and it isn't like a typical hematoma in that there are a few really dark spots that are in the center of it and there is a straight vertical line that doesn't go to the cuticle or the tip but there is a straight line and this whole blemish occupies about 35 percent of the toenail. Since the parts I can measure from have moved as the nail grows out, maybe it is just a hematoma but I am still scheduled for this biopsy. Should I get the biopsy done still, or cancel? It's going to take my nail off. I feel like it's a good move to get a biopsy done but I don't want to seem ridiculous either. Is it gauranteed to be benign if it is moving with the nail? Cancer haunts my family and I am a candidate. I could use some input on this. I appreciate your help!