Common Breast Conditions Phyllodes Tumor Phyllodes tumors are rare solid lumps that usually present as a mass found during a woman's breast self-examination or on a routine physical examination. Smaller masses may be detected mammographically. Phyllodes tumors appear very similar to a benign lump known as a fibroadenoma. These lumps are usually well circumscribed and painless. Imaging evaluation including a mammogram and ultrasound is usually performed and when a solid lump is identified a biopsy is important to obtain tissue for accurate diagnosis. A phyllodes tumor cannot be differentiated from a fibroadenoma by a needle biopsy. This means that your doctor may not be able to accurately tell you whether a solid lump is a benign fibroadenoma or a phyllodes tumor. Risk factors for phyllodes tumor are rapid growth and size greater than 2 cms. at the time of the evaluation. In many cases your doctor may recommend complete surgical removal of this mass to ensure that it is not an underlying phyllodes tumor. Phyllodes tumors are not all cancerous. Many will be classified as benign and not require further evaluation. A skilled pathologist is needed to distinguish a benign phyllodes tumor from one with more aggressive malignant potential. Women who undergo surgery for removal of a phyllodes tumor require close surveillance with a follow-up mammogram and physical examination at regular intervals. Malignant phyllodes tumors are best managed with a wide excision of normal breast tissue around the tumor to obtain clean margins. In most cases, radiation therapy is not required. Very large malignant phyllodes tumors may require complete removal of the breast for management.