[Multiple focal pure ground-glass opacities on HRCT images: clinical significance in patients with lung cancer].

Background and Objective: Some cases of lung cancer in addition to a primary tumor are associated with multiple pure ground-glass opacities (pGGOs). The objective of this study is to evaluate the clinical significance of multiple pGGOs on CT images of patients with lung cancer. The number, size, distribution, and morphological characteristics of the pGGOs were evaluated. Serial changes in pGGOs that were not surgically resected were analyzed at follow-up CT.
Methods: The cases of 25 patients with proven lung cancer and associated multiple pGGOs on CT images were retrospectively reviewed.
Results: In total, 207 pGGOs were detected. The size of the opacities ranged from 2 mm to 31 mm in largest diameter. Lung cancer and pGGOs were seen in the same lobe and/or in other lobes. Of the lesions, 183 (88.4%) had a round shape or well-defined border. Histological findings were obtained for 17 lesions representing 87 pGGOs that were surgically resected, namely, 13 atypical adenomatous hyperplasias, 3 bronchioloalveolar carcinomas, and 1 focal fibrosis. Of the 120 pGGOs followed up with CT for a median duration of 61.5 months, 113 (94.2%) retained their size, 1 decreased in size, and 6 disappeared.
Conclusions: The size of most pGGOs associated with lung cancer did not change during the follow-up period. Most of the lesions histologically diagnosed were atypical adenomatous hyperplasias or bronchioloalveolar carcinomas. The results justify the therapeutic strategy of resecting the primary tumor without therapeutic intervention in the remaining pGGOs.