im 37 years old,about 6 months ago i noticed a white mark about 2mm in size just above rim of the base of the penis head,at close inspection it looks like a couple of very thin white lines very slightly raised,in certain lights it appears to be a very faint line that goes right across the top side of the rim(corona) and fades towards outside, sometimes its hardly noticable apart from the bit i stated to start with which is slightly left of center.now this main part is about 5mm long along top of corona about 0.5mm width slightly raised with another small bit same width going vertically off of it,i spose it looks a bit like a very small scar and as i said it very faintly goes round rim of corona,ive been to doctors ans he said it doesnt look like anything to do with penile cancer which id my concern or std but to keep an eye on it,im very worried still and need advise,is it normal to have lines or marks like this on this glandular area please advise me,it doesnt itch either its just their,also i had thrush some months back could it be scar tissue from that