4 biopsy's - wouldn't my dr know if i have cancer?

Hello,

Welcome to ehealthforum and thanks for writing

Biopsy does help in ruling out the cause of any swelling.But you have not mentioned whether there is presence of swelling,any change in the size,associated pain or any other symptom,since how long has it been present,its location and other complaints if any.Various causes of swelling are there as infection,inflammation,endocrine disorder and rarely cancerous cause.
A detailed history and physical examination is quite inportant in ruling out the cause.Usually scans and Biopsy would help in making the exact diagnosis.
Kindly visit a Physician for evaluation and appropriate treatment.Usually most of the swellings are due to infection and subside on own or by use of antibiotics after sometime.
Take care!