White spots on arms!

[AndreMartins]

Hi,
Im a 15 years old boy... Ive always had some (not many) white spots on the back of my arms.... but in the begging of this summer they spreded all over my arms, my shoulders and starting to come up on my chest! Can I do anything about this?? Im 1.67m and 60kg! When I squeze a spot white fatty stuff comes out! Thank you, il be waiting for an answer.