I used to get cysts all over I think, but learned that oranges and OJ caused them. Eliminating oranges from my diet made the cysts I got all along my jawline, hairline, temples and neck go away. I'm pretty sure I got them on my chest too, but that wasn't the main problem. I learned the oranges were a trigger from a coworker who only got them on her chin after drinking OJ. Otherwise, she had great skin. You should try that. The results should be pretty immediate.
I still get some pretty inflamed and slow to heal zits on my back and always have one coming or going on my neck, but they are nothing like what I used to get. And the aspirin mask has made my back much better and have hopes it will help my neck.
I actually use it as a scrub in the shower rather than a mask and do my whole upper body. It makes your skin feel great. You should try it on your arms first. It might agravate the already inflamed chest area. It does agravate my rosecea so I don't use it on my cheeks.
Nothing a dermatologist ever prescribed helped me either. And they don't believe me about the oranges.