Breast biopsy and guidance for occult lesions.

Biopsy and histological examination is the only way of determining with absolute accuracy whether a lesion is benign or malignant, as well as its exact nature and whether it shows any evidence of precancerous changes. Occult malignant lesions, not clinically detectable, may be found by the study of surrounding tissue in the course of the excision of a benign lesion. However, they are most often found by breast x-rays (mammography or xerography) which are done for: the survey of high-risk asymptomatic women; contralateral breast studies; symptomatic breasts without palpable findings; nipple discharge; large pendulous breasts; and multinodular breasts. Biopsies for occult lesions, based on radiographic findings, are recommended for: suspicious calcifications; stellate-shaped masses; breast masses with ill-defined borders or nodular contours; dominant masses; and areas of increased density or distorted breast architecture. In general, biopsy for these lesions is best done under general anesthesia, as an in-patient and as a two-step type of procedure, i.e., the biopsy should be studied by permanent histologic sections before making a final diagnosis. Preoperative localization can be done by measurements, markers, radio-opaque dye injections or by needle localization which we feel is the preferred technique because it is simple and accurate and allows for removal of only a small amount of tissue with better cosmetic results. The advantages and disadvantages of various types of needle localization are discussed and figures are given for 387 needle localizations in which 148 cancers were found (38.2%). Of these cancers, 54.1% were invasive and 45.9% were noninvasive.(ABSTRACT TRUNCATED AT 250 WORDS)