title: Solitary lung cavities: CT findings in malignant and non-malignant disease.
abstract: OBJECTIVE
  To assess the computed tomography (CT) findings of solitary cavitary lesions which could potentially aid in differentiating malignant from non-malignant lung disease.
  
  
  METHODS
  A retrospective study of patients diagnosed with a solitary lung cavity at two university hospitals, who underwent multidetector CT examinations of the chest between 2012 and 2014, was performed. Lesions were evaluated for maximum diameter, maximum wall thickness, and associated findings. Statistical analyses were then conducted and a receiver operating characteristic (ROC) curve was calculated to select the most accurate cut-off value for malignant and non-malignant lesions.
  
  
  RESULTS
  CT and clinical records from 96 patients were reviewed. The most frequent aetiologies of non-malignant and malignant lung cavities were mycobacterial infection sequelae (50%, 33/66) and primary lung carcinoma (94%, 28/30), respectively. Significant differences (p<0.05) were found between malignant and non-malignant cases when comparing the averages of maximum wall thickness (15.2 and 7.8 mm, respectively) and maximum diameter of lesions (51 and 35 mm, respectively). The presence of either perilesional consolidation or centrilobular nodules favoured the diagnosis of non-malignant conditions (p<0.05). Maximum wall thicknesses thresholds of ≤7 or ≥24 mm were the most accurate in suggesting non-malignant and malignant aetiologies, respectively.
  
  
  CONCLUSIONS
  Malignant and non-malignant solitary lung cavities differ significantly at CT. Non-malignant lesions tend to exhibit thinner walls, but more perilesional consolidation and centrilobular nodules than malignant lesions. The results reveal that maximum wall thicknesses of ≤7 and ≥24 mm are indicative of non-malignant and malignant disease, respectively.
authors.affiliation: Federal University of Health Sciences of Porto Alegre, Brazil.
authors.forename: C S
authors.initials: CS
authors.lastname: Nin
authors.affiliation: Federal University of Health Sciences of Porto Alegre, Brazil.
authors.forename: V V S
authors.initials: VV
authors.lastname: de Souza
authors.affiliation: Post-graduation Program in Medicine (Radiology), Federal University of Rio de Janeiro, Brazil. Electronic address: grtalves@gmail.com.
authors.forename: G R T
authors.initials: GR
authors.lastname: Alves
authors.affiliation: Federal University of Health Sciences of Porto Alegre, Brazil.
authors.forename: R H
authors.initials: RH
authors.lastname: do Amaral
authors.affiliation: Radiology Department Liverpool Heart and Chest Hospital, UK.
authors.forename: K L
authors.initials: KL
authors.lastname: Irion
authors.affiliation: Post-graduation Program in Medicine (Radiology), Federal University of Rio de Janeiro, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Marchiori
authors.affiliation: Post-graduation Program in Medicine (Radiology), Federal University of Rio de Janeiro, Brazil.
authors.forename: B
authors.initials: B
authors.lastname: Hochhegger
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008168:Lung; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*