In survivors of breast cancer who subsequently develop a lung nodule, distinguishing between a metastatic breast cancer and a new primary lung carcinoma is critical in determining the proper treatment. This study outlines diagnostic approaches and therapeutic outcomes of such patients and identifies risk factors that adversely correlate with survival.
From 1977 through 2002, out of 5000 patients treated for breast cancer, 35 were identified with a synchronous or metachronous lung cancer. Data collected retrospectively included risk factors, presenting symptoms, diagnostic methods, histopathology, management, and survival. Median survival time and 2 year survival rate were determined by the Kaplan-Meier method and the log rank test. The relative risk (RR) derived from Cox regression was used to assess combinations of risk factors for their association with poor survival.
Nineteen patients (54%) were asymptomatic at the time of diagnosis and had their lung cancer discovered during workup and/or follow-up of their breast cancer. Thirty patients (85.7%) had non-small cell carcinoma - adenocarcinoma (31%) and squamous cell carcinoma (29%) were the most frequent histologic subtypes. The correct diagnosis of lung cancer was made preoperatively in 23 patients (82%). Nineteen patients (54%) were successfully treated with surgery. Mean follow up was 2.3 years. Median survival for all patients was 1.8 years. Factors associated with a statistically significant improvement in 2 year survival included asymptomatic presentation of lung cancer (P = 0.003), absence of tobacco use (P = 0.021), and lung cancer stage Ia or Ib (P = 0.009). Multivariate analysis revealed that tobacco use (RR = 3.6, P = 0.047) and advanced stage of lung cancer (II-IV) at the time of diagnosis (RR = 2.2, P < 0.001) were independent predictors of decreased survival.
The finding of a lung nodule in patients with breast cancer warrants a comprehensive evaluation, including tissue biopsy, to differentiate between primary lung and metastatic breast cancers.
Diagnosis and resection of a second primary lung cancer in the early stages can lead to improved survival.
F. Kerendi, None.