title: Characteristics of subsolid pulmonary nodules showing growth during follow-up with CT scanning.
abstract: OBJECTIVE
  The positive results of a screening CT scan trial are likely to lead to an increase in the use of CT scanning, and, consequently, an increase in the detection of subsolid nodules. Noninvasive methods including follow-up with CT scanning, to determine which nodules require invasive diagnosis and surgical treatment, should be defined promptly.
  
  
  METHODS
  Between 2000 and 2008, from our database of . 60,000 examinations with CT scanning, we identified 174 subsolid nodules, which showed a ground-glass opacity area . 20% of the nodule and measured 2 cm in diameter, in 171 patients. We investigated the clinical characteristics and CT images of the subsolid nodules in relation to changes identified during the follow-up period.
  
  
  RESULTS
  The nodule sizes ranged from 4 mm to 20 mm at the fi rst presentation. Nonsolid nodules numbered 98. During the follow-up period, 18 nodules showed resolution or shrinkage, and 41 showed growth of 2 mm or more in diameter. The time to 2-mm nodule-growth curves calculated by Kaplan-Meier methods indicated that the 2-year and 5-year cumulative percentages of growing nodules were 13% and 23% in patients with nonsolid nodules and 38% and 55% in patients with part-solid nodules, respectively. Multivariate analysis disclosed that a large nodule size ( . 10 mm) and history of lung cancer were significant predictive factors of growth in nonsolid nodules.
  
  
  CONCLUSIONS
  An effective schedule for follow-up with CT scanning for subsolid nodules should be developed according to the type of subsolid nodule, initial nodule size, and history of lung cancer.
authors: Divisions of Thoracic Surgery, Tochigi Cancer Center, Utsunomiya, Japan. Electronic address: hmatsugu@tcc.pref.tochigi.lg.jp.
authors: Haruhisa
authors: H
authors: Matsuguma
authors: Thoracic Diseases, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Kiyoshi
authors: K
authors: Mori
authors: Divisions of Thoracic Surgery, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Rie
authors: R
authors: Nakahara
authors: Divisions of Thoracic Surgery, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Haruko
authors: H
authors: Suzuki
authors: Thoracic Diseases, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Takashi
authors: T
authors: Kasai
authors: Thoracic Diseases, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Yukari
authors: Y
authors: Kamiyama
authors: Pathology, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Seiji
authors: S
authors: Igarashi
authors: Thoracic Diseases, Tochigi Cancer Center, Utsunomiya, Japan.
authors: Tetsuro
authors: T
authors: Kodama
authors: Division of Thoracic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: Kohei
authors: K
authors: Yokoi
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D049109:Cell Proliferation; D019468:Disease Management; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D036542:Tomography, Spiral Computed