[1623] Histological Characteristics in the Prediction of Acute Exacerbation of Idiopathic Pulmonary Fibrosis (IPF) Following Surgery for Primary Lung Cancer

O Matsubara, T Ohba, H Ninomiya, Y Ishikawa, EJ Mark. National Defense Medical College, Tokorozawa, Japan; Cancer Institute, Tokyo, Japan; Massachusetts General Hospital and Harvard Medical School, Boston, MA

Background: Idiopathic pulmonary fibrosis (IPF) is associated with lung cancer with a reported frequency of between 13 and 31%. Although the postoperative mortality rate in patients with lung cancer has decreased with advances in clinical management, patients with IPF remain at a high risk of complications. The incidence of acute exacerbation of IPF after lobectomy has been as high as 20%. We sought to determine whether or not there are any histological characteristics that suggest acute exacerbation of IPF in surgically resected lung specimens.
Design: A retrospective study of 735 patients undergoing resection of lung cancer revealed that 27 patients had IPF based on clinical and radiological records. These cases were analysed by quantitative histopathology.
Results: Five of the 27 patients with IPF showed histologic evidence of acute exacerbation of IPF. Four of the five died 20 to 40 days after the lung resection, and one patient survived after steroid pulse therapy. The histologic findings in patients with IPF with and without acute exacerbation were temporal and spatial variation, patchy involvement, subpleural accentuation of disease, honeycomb change, fibroblastic foci and interstitial inflammation. There were three prominent findings when compared to the remainder of the cases: 1) more marked interstitial inflammation with neutrophil and eosinophil, 2) more frequent lymphoid aggregates, and 3) more extensive accumulation of macrophages. There were no significant differences in the frequency of fibroblastic foci, the degree of bronchiolar metaplasia, type 2 pneumocyte hyperplasia, squamous metaplasia, or honeycomb fibrosis between the two groups.
Conclusions: More prominent and numerous active fibroblastic foci have been shown to be a marker of a more ominous course including acute exacerbation in patients with IPF. In this study, however, the presence of interstitial pneumonitis is more predictive of the accelerated phase of usual interstitial pneumonia (UIP) than the presence of active fibroblastic foci.
Category: Pulmonary

Monday, March 9, 2009 1:00 PM

Poster Session II # 230, Monday Afternoon