title: Pulmonary ground-glass opacity (GGO) lesions-large size and a history of lung cancer are risk factors for growth.
abstract: OBJECTIVE
  Ground-glass opacity (GGO) of the lung is being frequently detected by thin section computed tomography scan. However, the long term management of detected GGO is still unclear. To establish follow-up plans, we performed the clinical and radiological review to identify the factors that are closely associated with GGO growth.
  
  
  METHODS
  We retrospectively analyzed computed tomography images of 125 GGOs that were stable for 3 months between 1999 and 2006 at the Cancer Institute Hospital, Tokyo. To identify factors that affect the roentgenological growth, the time to GGO growth curve by Kaplan-Meyer method was evaluated in terms of gender, age, smoking, initial size, existence of a solid part, GGO density, location, multiplicity, and lung cancer history by univariate and multivariate analyses.
  
  
  RESULTS
  The median observation period was 1048 days (177-3269) and 26 of 125 GGOs (21%) grew. The estimated growth population for 5 years was 30%. The growth was more frequently seen in the elderly (p = 0.017), in part-solid GGO (p < 0.01) and in GGO of larger than 10 mm (p < 0.01, logrank test). By multivariate analysis, initial size (p < 0.01, Cox's model) and history of lung cancer (p = 0.017, logistic model) were independent factors that were significantly associated with GGO growth. Fifty GGOs that were 10 mm or smaller and without a lung cancer history did not grow within 3.5 years.
  
  
  CONCLUSIONS
  After initial management and 3 month follow-up, larger size (more than 10 mm) and a history of lung cancer are risk factors for GGO growth, and therefore should be considered when making a follow-up plan.
authors.affiliation: Department of Thoracic Surgical Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Koto-ku, Tokyo, Japan.
authors.forename: Miyako
authors.initials: M
authors.lastname: Hiramatsu
authors.forename: Takuya
authors.initials: T
authors.lastname: Inagaki
authors.forename: Tomoya
authors.initials: T
authors.lastname: Inagaki
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Matsui
authors.forename: Yukitoshi
authors.initials: Y
authors.lastname: Satoh
authors.forename: Sakae
authors.initials: S
authors.lastname: Okumura
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Etsuo
authors.initials: E
authors.lastname: Miyaoka
authors.forename: Ken
authors.initials: K
authors.lastname: Nakagawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed