560 patients with primary broncho-pulmonary carcinoma underwent surgery, excision being possible in 78 p. cent. Overall post-operative survival is 29 p. cent at 5 years and 11.5 p. cent at ten years. Among the various prognostic factors, lymph node involvement is the most important. In the most favourable cases, survival at 5 years is 46 p. cent. Such a result shows that the prognosis in primary carcinoma of the lung is not as grim as it is usually said to be.