What things could cause a breast lump?

Depends: Could be benign fibrocystic disease, benign fibroadenona, or benign breast cyst. Breast cancer can be a firm breast lump. Painful abscess or infection is possible. Need to see a doctor for an examination.

Benign or malignant: If you feel a breast lump or mass you should get it taken care of. You should get a referral to a doctor who specializes in breast disease the best doctor would be a breast surgeon you need to have a history and exam and mammogram and or breast ultrasound and probably need a biopsy.