Abstract
Objective: The detection of localized ground-glass opacity (GGO) on HRCT is important for the diagnosis of peripheral adenocarcinomas with a bronchioloalveolar growth pattern of alveolar lining cells. We report two cases of benign lesions 2 cm or less in diameter that showed localized GGO (80% or more of the lesion area).
Materials and Methods: The extent of GGO within lesions on preoperative HRCT in 232 surgically resected small lung nodules (≤2cm) was reviewed retrospectively by three chest radiologists. Forty-nine lesions (≤2cm) with GGO (80%≥) on HRCT in 49 patients (22 men and 27 women; mean age, 58.2 years) were studied.
Results: Forty-seven out of 49 lesions with GGO (80%≥) were adenocarcinomas (Noguchi's classification for small adenocarcinoma: type A; 22, type B;, 20, type C; 5), and two lesions were benign lesions, pulmonary lymphoproliferative disorder and sarcoidosis. In a 37-year-old-man with pulmonary lymphoproliferative disorder, HRCT revealed a nodule with GGO (15mm), and a slight increase in size, 2 year later. Wedge resection was performed, and analysis showed that the resected specimen was pulmonary lymphoproliferative disorder. In a 69-year-old-woman with sarcoidosis, bilateral hilar lymph node enlargement was noted on chest radiographs, and HRCT revealed a nodule with GGO (8mm). Partial resection and hilar lymph node biopsy was performed, and analysis showed that the resected specimen was sarcoidosis.
Conclusion: Most peripheral lung lesions (≤2cm) with an 80% or greater area of GGO on HRCT are adenocarcinomas, type A or type B; however, in such cases it is also necessary to consider benign lesions such as pulmonary lymphoproliferative disorder and sarcoidosis.
