Patients with axillary bulge, the common causes are lipoma, paratesticular breast and so on: 1, lipoma: local fat tissue hyperplasia formed by lipoma, which is a relatively common benign disease in clinic, through ultrasound examination can be clear about the size and specific nature of the volume of lipoma, the volume of smaller lipoma can be regularly reviewed, but if the volume of the lipoma is gradually increasing, accompanied by pain symptoms, you can consider the line of 2, paratesticular breast: young female patients may have paratesticular breasts in the armpit, which may also be manifested as localized bulge, paratesticular breasts are caused by congenital breast development abnormality of the patients, generally speaking, paratesticular breasts are accompanied by normal mammary glands, and they may also have recurring pain, or even cancerous, therefore, patients with paratesticular breasts may consider surgical excision. 3, skin follicular infection or sebaceous cyst and infection: patients with localized skin follicular infection or sebaceous cyst and infection may be considered to be surgically removed. Localized skin hair follicle infection or sebaceous cyst and infection, may also appear bulging phenomenon, this situation can be considered for surgical treatment.