Ectopic
breast tissue can occur anywhere along the incompletely regressed mammary
ridge . Among the various types of
breast choristoma , ectopic
breast tissue , which has only glandular
tissue without a
nipple or
areola , is most commonly detected in axillary areas. However, ectopic
breast cancer is often not detected until significant clinical symptoms have been revealed, or
diagnosis is delayed. Furthermore, an examination of ectopic
breast tissue tends to be omitted from a
screening mammography . Especially, the
microcalcifications of ectopic
breast tissue are difficult to delineate on
mammography . Herein, the authors
report a case of ectopic
breast carcinoma that showed clustered
microcalcifications on
screening mammography , and discuss the interpretation and implications of
microcalcification in ectopic
breast tissue .