The authors report on 182 cases of intrathoracic metastases (ITM = lung, pleura or mediastinum) observed as first single recurrences in the course of the follow-up of patients treated for primary breast cancer. ITM were detected on standard two-views chest X-ray (CXR) at regular follow-up visits and in absence of subjective symptoms (102 A cases) or in the interval between two consecutive planned controls because of the onset of subjective symptoms (80 S cases). The average disease-free interval since primary treatment was significantly shorter in A with respect to S cases (40.3 vs. 28.5 months, P less than 0.001) as a consequence of the early detection achieved by CXR survey. On the contrary, prognosis was not influenced by ITM early diagnosis as the 10-year survival since primary treatment did not differ significantly between A or S cases (12% vs. 10%, P = 0.68). Results were confirmed on multivariate (Cox's) analysis, adjusting for potential confounders such as age or nodal status. Periodic CXR survey looks a very questionable policy as it does not seem to have any favourable impact on prognosis. Its routine use in breast cancer patients should thus be carefully reconsidered.