Ho Yun Lee MD, Presenter: Nothing to Disclose

Kyung Soo Lee MD, PhD, Abstract Co-Author: Nothing to Disclose

Yeon Joo Jeong MD, Abstract Co-Author: Nothing to Disclose

Jung Hwa Hwang MD, Abstract Co-Author: Nothing to Disclose

Hyojin Kim MD, Abstract Co-Author: Nothing to Disclose

Man Pyo Chung, Abstract Co-Author: Nothing to Disclose

Joungho Han, Abstract Co-Author: Nothing to Disclose

Chin A Yi MD, PhD, Abstract Co-Author: Nothing to Disclose

Myung Jin Chung MD, Abstract Co-Author: Advisory Board, Samsung Advanced Institute of Technology Research Consultant, Samsung Mobile Display Company

Tae Sung Kim MD, Abstract Co-Author: Nothing to Disclose

Regarding FIP with no or little honeycombing (HC) (< 5% of lung volume) at the initial CT, its long term CT changes and relationship with mortality has still been unknown. This study aimed to evaluate the baseline CT findings and their long term changes in patients with FIPs of little or no HC on CT at the time of pathologic diagnosis, and to clarify prognostic markers among CT findings.

This study included 200 patients with FIP (< 5% HC) who were followed up clinically for minimum two years. Patients were classified into 4 groups; 101 UIP, 53 fibrotic NSIP, 19 CVD-UIP, 27 CVD-NSIP. Extent and distribution of FIP-related CT findings were assessed visually by 3 independent observers. Serial CT scans of a minimum 6-month follow-up period were also evaluated in 167 FIP patients (85, 47, 12, 23 patients,respectively). Median interval period between baseline and follow-up CT were 2.8 years (0.3–13.1). Comparison of baseline CT findings and changes on follow-up CT among 4 subgroups were evaluated. Median duration of follow-up for mortality was 5.2 years (0.6 – 13.5), and the correlation between CT findings and mortality was also analyzed.

Baseline CT findings included 21% reticulation & 11% GGO for UIP, 13% & 23% for fibrotic NSIP, 22% & 21% for CVD-UIP, 16% & 17% for CVD-NSIP. There were significant differences in the extents of reticulation and GGO among four subgroups (P<.001). Follow-up CT showed development of HC (5% in UIP, 3% in fibrotic NSIP, 2% in CVD-UIP, 1% in CVD-NSIP, P=.12),decrease in the extent of GGO (2%, 10%, 13%, 4%, respectively; P =.004), and increase in the extent of reticulation (3% in UIP, 8% in fibrotic NSIP, 9% in CVD-NSIP). At serial CT, lung lesions showed change in distribution from subpleural to random in 15% and from basal to random in 16% in UIP. Interval periods of serial CT showed no significant difference among four subgroups (P=.32). Patients with random distribution (involvement of both central and peripheral) of lung fibrosis had a shorter overall survival period than those with subpleural distribution (0.8 vs. 4.5 yrs, P =.002, log-rank test).

FIP with little or no HC at baseline CT shows the progression of fibrosis and HC development, however, fibrosis progression extent is not different among 4 different subgroups.

Random distribution of lung fibrosis on transverse images can be a prognostic imaging marker for FIP patients.

Lee, H, Lee, K, Jeong, Y, Hwang, J, Kim, H, Chung, M, Han, J, Yi, C, Chung, M, Kim, T, Pathologically-proved Fibrotic Interstitial Pneumonias with No or Little Honeycombing at Initial CT: Long Term Changes in CT Findings and Prognostic Value.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9006514.html