Hi. I am 24, male, weight - 63 kg, height 170 cm. I have a cyst on the inner side of the upper left arm. It s almost near the skin surface, and appears like a swollen rounded part of a vein. It does not hurt in general unless it is pressed hard. However it has grown very slowly over the past three years.It s not too hard, not to soft to press and does not move about much when pressed. Any idea as to what it can be? Thanks.