DIFFERENTIAL DIAGNOSIS AND MANAGEMENT OF FOCAL GROUND-GLASS OPACITIES

Focal pulmonary Ground-Glass Opacities (GGOs) can be associated with bronchioloalveolar carcinoma. This retrospective study aims at testing the validity of a multistep approach to discriminate malignant from benign localized (focal) GGOs, identifying useful diagnostic features on CT, and suggests appropriate management guidelines. A stepwise approach including oral antibiotics, follow-up High-Resolution CT 40-60 days later, and CT-guided core biopsy was used. All cases with localized GGOs detected since 2001 were reviewed, CT features were described according to a structured scheme. 40 patients were evaluated. Eleven patients were diagnosed with benign GGOs, 19 patients had lung cancer, and 10 are still undetermined. Non-polygonal shape (p=0.006), apparent radial growth (p=0.010), and clear-cut margins (p=0.003) were associated with a malignant histology. The specificity of CT findings was low. Diagnostic accuracy increased after oral antibiotics, follow-up High-Resolution CT, and percutaneous core biopsy. 18 patients underwent surgery for lung cancer. In conclusion, malignant GGOs have a fairly typical appearance, but some benign lesions closely mimic their malignant counterparts. The stepwise approach we adopted increases the diagnostic specificity and reduces time to definitive diagnosis. Segmentectomy might be the ideal resection volume for such tumours