Hi, I have a similar story, a dark line appeared down my thumbnail about a year ago, GP unconcerned but after googling and realising what it could be I went back to see her. Finally got my appointment with Dermatologist yesterday and she said the line grows wider going into my cuticle and she suspects there is a mole underneath. I am now waiting for a biopsy (peeling back the skin, yuck) I am more uncomfortable at the thought of the biopsy right now and can focus on nothing else! I am a single parent and cater to my 10yr old son who has Autism and ADHD and I'm worrying that I won't be able to do all the cooking/cleaning etc. Anyone with experience of the biopsy procedure and aftercare please? Thanks in advance, Rachael