Objective To investigate the risk factors, diagnosis and treatment of solitary pulmonary nodule （diameter≤3cm）. Methods From Jan. 2001 to Dec. 2002, the clinical data of 297 patients with solitary pulmonary nodule were reviewed. Chi-square or t-test were used in univariate analysis of age, gender, symptom, smoking history, the size, location and radiological characteristics of nodule, and logistic regression in multivariate analysis. Results Univariate analysis revealed that malignancy was significantly associated with age （P=0. 000）, smoking history （P=0. 001）, the size （P=0. 000） and radiological characteristics （P=0. 000） of nodule. In multivariate analysis （logistic regression）, it was significantly associated with age （OR = 1. 096）, the size （OR = 2. 329） and radiological characteristics （OR=0. 167） of nodule. Conclusion Age and the size of nodule could be risk factors. Radiological findings could help distinguish from malignant nodules.
With widespread utilization of multi-slice helical computed tomography (CT) and low-dose CT in lung cancer screening, significantly greater incidence of patients with solitary pulmonary nodules (SPN) has been found. Once SPN is discovered, it is very difficult to immediately determine whether it is benign or malignant in clinical practice. In this review, SPN etiology, epidemiological characteristics of SPN patients, nodule size, morphology, location and growth rate, mathematical models for predicting malignancy of SPN, and diagnostic value of positron emission tomography (PET) and positron emission tomography-computed tomography (PET/CT) are summarized to provide reference for differential diagnosis of SPN. Current management strategies for SPN are also discussed in this review. According to whether SPN diameter is greater than 8 mm, whether SPN patients are advanced aged, have smoking or malignancy history, different follow-up and treatment strategies can be chosen. The diagnostic and treatment value of video-assisted thoracoscopic surgery for SPN is also discussed.