<s>[INST] Ive had a lump in my right armpit for quite awhile now Im currently a 15 year old female and Ive had this lump for almost over a year now it started out small about the size of a marble and was slightly painful to hold the doctor told me it was nothing, I saw the doctor again after some months  since it seemed to get slightly bigger he said to get an ultrasound of it but nothing was seen, currently its slightly big and it feels like a piece of fat thats slightly firm about 3-4 cm big Im just worried since its still there any advice? [/INST] Hi.it is best if you consult with a doctor, preferably a general surgeon, for medical and physical examination. Based from your description, it could be hi Chat Doctor.  These lesions usually occur on the underarm, especially after shaving or plucking and/or usage of deodorants with strong chemical contents. Hair follicles get infected. Inflammation and subsequent abscess formation occur. Other possibilities are cystic lesions, fibrous or lipoma (fatty deposit). Medical (proper antibiotic regimen) and surgical (excision or incision and  </s>