Feng Li MD, PhD, Presenter: License agreement, Hologic, Inc License agreement, General Electric Company License agreement, Toshiba Corporation License agreement, Deus Technologies, LLC License agreement, Riverain Technologies, LLC License agreement, MEDIAN Technologies License agreement, Mitsubishi Corporation

Samuel George Armato PhD, Abstract Co-Author: Nothing to Disclose

Heber MacMahon MD, Abstract Co-Author: Shareholder, Hologic, Inc Consultant, Riverain Technologies, LLC Royalties, UCTech

 To evaluate the clinical significance of solitary non-calcified nodules on chest computed tomography (CT) scans in patients with breast cancer.

 Of 3313 patients with breast cancer, 1377 patients had at least one chest CT scan between 2002 and 2011 at our medical center. Considering the first CT scans of these 1377 patients, 630 (46%) patients had no lung nodules, 529 (38%) patients had multiple nodules, and 218 (16%) patients had one non-calcified nodule. Of the 218 CT scans with a solitary pulmonary nodule, the CT section thickness was 1 mm in 138 (63%) scans, 2-3 mm in 12 (6%) scans, and 3-7 mm in 68 (31%) scans. The size and pattern of these 218 solitary nodules on CT were analyzed and compared with the final diagnosis.

 The mean dimensions of the 218 solitary nodules on CT was 3-5 mm in 160 (73%) patients, 6-10mm in 34 (16%) patients, 11-20 mm in 16 (7%) patients, and 21-40 mm in 8 (4%) patients. There were 185 (85%) solid nodules, 26 (12%) nodules with mixed ground-glass opacity (GGO), and 7 nodules with pure GGO. Final diagnosis included 100 (46%) definitely benign lesions (resolved or stable solid nodule after more than 2 years or biopsy proven), 72 (33%) benign lesions based on image features alone, 21 (10%) indeterminate or suspicious lesions, 11 (5%) primary lung cancers, and 14 (6%) nodular metastases (all solid nodules). 201 (92%) lesions were diagnosed by imaging findings alone, and only 17 (8%) lesions were confirmed by biopsy (11 lung cancers, 3 benign nodules, and 3 metastatic breast cancers). Among 160 nodules at 3-5 mm, 141 (88%) were benign lesions, 12 (8%) were indeterminate or suspicious lesions, 7 (4%) were metastatic nodules, and no primary lung cancers were found. All 7 pure GGO nodules were indeterminate or suspicious by follow-up CT scans.

  90% of 3-5 mm and 67% of 6-10 mm solitary solid non-calcified nodules in patients with breast cancer were benign, whereas 5% of 3-5 mm and 17% of 6-10 mm of such nodules were metastases. 

 The detection of small solitary solid nodules on the initial CT scans of patients with breast cancer should not be a cause for alarm as the large majority are benign, and follow-up CT scans are usually appropriate to confirm benignity in such cases.

Li, F, Armato, S, MacMahon, H, Clinical Significance of Solitary Lung Nodules in Patients with Breast Cancer.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011371.html