Casey J J, Stempel B G, Scanlon E F, Fry W A
Surgery. 1984 Oct;96(4):801-5.
A solitary pulmonary nodule appearing in a patient with breast cancer, either past or present, is most likely to be a second primary cancer originating in the lung rather than a metastasis from the breast cancer. Between 1970 and 1983 there were at this institution 1416 patients with breast cancer and 579 patients with bronchogenic cancer, 198 of whom were women. Among the patients with breast cancer, 42 (or 3% of all of the patients with breast cancer) had a solitary pulmonary nodule either at the time of presentation of their breast cancer or during the follow-up period. Fifty-two percent of the solitary pulmonary nodules proved to be a primary lung tumor, 5% proved to be benign lesions, and only 43% proved to be metastatic breast cancer. Patients with breast cancer with solitary pulmonary nodules should have a diagnostic workup appropriate for lung cancer. Since adenocarcinoma has become the most common lung cancer cell type, the usual diagnostic tests may not allow a firm differentiation between primary lung and secondary breast cancer. Therefore if malignancy is proved or suspected, thoracotomy with appropriate resection is the treatment of choice in most patients with breast cancer, even at the initial appearance of the breast cancer.
在患有乳腺癌（无论既往还是现患）的患者中出现的孤立性肺结节，极有可能是起源于肺部的第二原发性癌症，而非乳腺癌转移所致。1970年至1983年间，该机构有1416例乳腺癌患者和579例支气管源性癌患者，其中198例为女性。在乳腺癌患者中，42例（占所有乳腺癌患者的3%）在乳腺癌初诊时或随访期间出现了孤立性肺结节。52%的孤立性肺结节被证实为原发性肺肿瘤，5%为良性病变，仅有43%被证实为乳腺癌转移。患有乳腺癌且有孤立性肺结节的患者应接受适用于肺癌的诊断性检查。由于腺癌已成为最常见的肺癌细胞类型，常规诊断检查可能无法明确区分原发性肺癌和继发性乳腺癌。因此，如果证实或怀疑为恶性肿瘤，对于大多数乳腺癌患者，即使在乳腺癌初发时，开胸并进行适当切除是首选的治疗方法。
