Atypical carcinoids are an intermediate form of tumor between low-grade malignant typical carcinoid and high-grade malignant small cell carcinoma, which represent the two ends of the spectrum of neuroendocrine bronchopulmonary tumors. Between 1983 and 1993, 27 patients with atypical carcinoids underwent surgical treatment. The histologic diagnosis of an atypical carcinoid was established if the criteria proposed by Arrigoni and associates were fulfilled. Seven pneumonectomies, 16 lobectomies, 2 segmentectomies, and 2 wedge resections were performed. Thirteen patients (48.1%) had regional nodal metastases and 6 patients (22%) had N2 disease at the time of surgical therapy. Distant metastases developed in 5 patients (18.5%) after initial treatment. The 10-year survival in patients with an atypical carcinoid was 49%, versus the 84% 10-year survival rate observed in patients with a typical carcinoid. We conclude that the aggressive behavior of atypical carcinoids precludes the use of limited surgical resection and requires a more aggressive approach, with lobectomy and mediastinal lymph node dissection constituting a minimal procedure. The same criteria used for well-differentiated lung carcinoma should apply to this form of neuroendocrine lung tumor. Adjuvant chemotherapy is recommended for patients with stage III or distant metastases.