Hi Kayde! Good afternoon. I am Dr Shareef answering your query. As per the history narrated by you about the swelling on the back of your friend, this seems to be a slow growing lump, which intermittently gets inflamed giving rise to pain. The common such swellings could be a dermoid, a pilonidal cyst, or a sebaceous cyst. However, it needs a physical examination of the lump and so, I would advise you to get it clinically assessed by a general surgeon along with related investigations for a definitive diagnosis and proper management. Till then he could go for an anti inflammatory drug along with a proton pump inhibitor for a symptomatic relief. I hope this information would help you in discussing with your family physician/treating doctor in further management of your problem. Please do not hesitate to ask in case of any further doubts. Thanks for choosing health care magic to clear doubts on your health problems. I wish you an early recovery. Dr Shareef.