Pulmonary Pleomorphic Carcinoma: Its Clinical Behavior, Prognostic Factor, and Keys to Treatment

Objective. Due to its rarity, the clinical behaviour of pulmonary pleomorphic carcinoma has not been elucidated. This study aimed to investigate the prognosis and prognostic factors of pulmonary pleomorphic carcinoma, especially factors associated with early recurrence and death. Methods. We retrospectively investigated 44 cases of pulmonary pleomorphic carcinoma. All patients underwent complete surgical resection. Factors affecting survival were assessed by the Kaplan-Meier method, and Cox regression and logistic regression analyses. Results. The prognosis of pleomorphic carcinoma was severe. In particular, there were high rates of early recurrence and death after surgery (the 1-year overall survival and recurrence-free survival rates were 52.6% and 45.8%). Although pleural invasion (P=0.95) and lymphatic invasion (P=0.39) did not affect the prognosis, patients with vascular invasion had a significantly worse prognosis than patients without vascular invasion (P=0.042). Similarly, tumors consisting mainly of sarcomatous elements showed a poorer prognosis than those consisting mainly of epithelial components (P=0.094). A multivariable Cox regression analysis revealed that vascular invasion was independently associated with a poor prognosis (hazard ratio, 3.11; 95% confidence interval, 1.04-13.3; P=0.026), and tumors consisting mainly of sarcomatous elements tended to have a poor prognosis (hazard ratio, 2.21; 95% confidence interval, 0.88-6.29; P=0.089). In addition, vascular invasion and tumors consisting mainly of sarcomatous elements were identified as risk factors for early recurrence and death after surgery by a multivariable logistic regression analysis. Conclusions. The prognosis of patients with pulmonary pleomorphic carcinoma is severe. Vascular invasion and tumors consisting mainly of sarcomatous elements are poor prognostic factors.