The differential diagnosis of solitary pulmonary nodules (SPNs) using radiological features in patients with breast cancer is vital yet difficult. The nature of SPNs, of these patients, as well as the role of surgery in the diagnosis and treatment were evaluated. Thirty consecutive patients, who underwent surgery for an SPN between 2002 and 2011 subsequent to curative surgery for breast cancer were retrospectively evaluated. The overall survival and disease-free survival periods were estimated using the Kaplan-Meier method. The Student's t-test and the χ2 test were performed to compare percentages and the mean values, respectively. The values were considered statistically significant at P<0.05. Most (93%) SPNs were malignant. The pathological diagnoses in patients with SPNs were primary lung cancer (n=20, 67%), pulmonary metastasis from breast (n=7, 23%) or colon (n=1, 3%) cancers and benign conditions (n=2, 7%). Of the 20 patients with primary lung cancer, 15 (75%) had stage IA tumors (T1aN0M0). The average disease-free interval was significantly longer in patients with primary lung cancer compared to patients with pulmonary metastases from breast cancer (P= 0.031). The five-year survival rates after pulmonary resection for lung metastasis from breast cancer patients and primary lung cancer patients were 100 and 61.1%, respectively. SPNs found in patients with breast cancer were found to have a high probability of malignancy, especially primary lung adenocarcinoma. The early resection of SPNs in patients diagnosed with both primary and metastatic lung cancer led to a good prognosis. The early pathological diagnosis by surgical resection was suggested to be conducted for the early diagnosis and appropriate treatment of SPNs in patients with breast cancer.
Keywords: breast cancer; metastasectomy; primary lung cancer; solitary pulmonary nodule; surgery; video-assisted thoracoscopic surgery.