Benign Tumors

A tumor in the breast is the most common complaint for which a woman consult a physician. Patients refer to this finding as a "lump", "thickening" or "mass". The Physician oftentimes also uses that terminology. But  because "mass" and "tumor" have different clinical significance, the physician should be able to distinguish between them.
A tumor is a clinical entity that has three dimensions: width, height and depth. For didactic purposes, a tumor can be compared with a rubber ball. With the rubbe ball held hidden halfway within the palm of one hand, the protruding surface of the ball is palpated using the index and second fingers of the opposite hand. Because of the perception of depth ("streognosis"), the clinician (or the patient during self-examination) can perceive that there is "something behind" that surface.
On the other hand, a mass in an entity that has only two dimensions: width and length. On examination, the clinican can feel an area of thickening that, at each extreme, blends with the breast tissue rather than forming a defined edge. A mass is a clinical finding present in some histologic types of fibrocystic changes, such as hyperplasia (see "Fibrocystic Changes" later in this chapter).
Approximately 70% of breast tumors are benign. The fact that 30% of all breast lesions could be malignant is significant. The physician should not only be aware of these percentages but should also know which breast lesions are the most common and how to make a clinical differential diagnosis.
The breast problems most commonly seen in a medical practice not specialized in breast diseases are fibroadenoma and some of its variants-giant fibroadenoma, juvenile fibroadenoma, hamartoma- and phyllodes tumors,  cysts, and cancers. Because this textbook is intended as a guide for physicians and general surgeons whose practices iclude the care of women, only the most common breast tumors and their surgical treatment are discussed. For less common tumors, the reader is referred to the textbooks and literature listed in "Suggested Readings" at the back of this book.