Objective: Identification of clinical features suggestive of pulmonary blastoma (PB) through a retrospective comparison with cases of non-small cell lung cancer (NSCLC) operated during the same period. Methods: Between 1977 and 1999, five patients were operated for PB at Geneva University Hospital (four women and one man, aged 32-46 years - mean 36.8) versus 1913 consecutive patients (1558 men and 355 women, mean age 61.2) for primary NSCLC. In the PB subgroup (0.3%), the pulmonary tumor was single, located in an upper lobe in all but one instance, and measured between 5 and 13 cm (mean 9.6), whereas in the total NSCLC group, 27% of patients had tumors <3 cm (T1), evenly distributed in both lungs. All but one PB patients were symptomatic, compared to 45% in the NSCLC group. Results: The five patients with PB underwent curative pulmonary excisions (lobectomy in three and pneumonectomy in two) with mediastinal lymph node sampling. Pathological examination revealed extensive tumor necrosis in four, and N2 lymph node metastases in four (in the total NSCLC group, N2 disease was diagnosed in 21%). Postoperatively, three PB patients received radio- and/or chemotherapy. Four patients died between six and 30 months after the operation (mean 15), whereas 5-year survival in the NSCLC group was 32%, with a median survival of 3.7 years; the fifth patient is alive 28 months later, without any sign of recurrence. Conclusions: Compared to operated NSCLC, PB are rare, large, and symptomatic tumors; they affect younger patients and carry a worse prognosi
