Micropapillary Lung Cancer with Breast Metastasis Simulating Primary Breast Cancer due to Architectural Distortion on Images

Common image findings of breast metastases from extramammary malignancy are single or multiple, round, usually circumscribed mass(es) variable in size (1). This is known to be due to a nonductal pattern of metastatic spread and lack of desmoplastic reaction in breast metastasis. If architectural distortion is seen on mammography, the possibility of metastasis from extra-mammary malignancy is very low and primary breast lesion including primary cancer is rather favored. Micropapillary Lung Cancer with Breast Metastasis Simulating Primary Breast Cancer due to Architectural Distortion on Images Kyungran Ko, MD, Jae Yoon Ro, MD , Eun Kyung Hong, MD, Seeyeon Lee, MD Departments of Diagnostic Radiology, Pathology, and Surgery, Center for Breast Cancer, National Cancer Center, Goyang 410-769, Korea; Department of Pathology, The Methodist Hospital, Weill Medical College of Cornell University, Houston, TX, USA