Solitary pulmonary nodule (SPN) is a challenging problem especially for the chest physicians and thoracic surgeons. Radiologic diagnosis and classification of an SPN in terms of margins, size and doubling time are very important but insufficient. Definitive diagnosis of an SPN depends on histopathologic examination. Differntial diagnosis of an SPN less than 10 mm is more difficult because sensitivity and accuracy of the diagnostic methods will also decrease with decreasing dimension. Conventional radiologic methods as chest X-ray and low dose CT have been widely used for screening high risk patients for lung cancer however this methods are insufficient for small SPN. Latest method, FDG PET CT, also depends on the size of the lesion. The sensitivity, specificity, and accuracy were 85%, 36% and 54% respectively for nodules smaller than 10 mm, compared to 91%, 47%, and 79% for nodules between 1.1-2.0 cm. Sensivity and accuracy of histopathologic diagnosis with fine needle biopsy for small SPN depend on the location of the lesion. The accuracy of the biopsy improves in peripheral nodules. Surgical excision of the SSPN via VATS can provide definitive diagnosis and treatment, however major lung resection and mediastinal lymph node dissection are the most effective treatment methods for malign nodules.
Keywords: Pulmonary nodule, Lung Cancer, Less than one centimeter, VATS.