Blair Gordon Gill MD, Presenter: Nothing to Disclose

Jean Seely MD, Abstract Co-Author: Nothing to Disclose

Frederick Robert Karl Matzinger MD, Abstract Co-Author: Nothing to Disclose

Carolina Althoff Souza MD, Abstract Co-Author: Nothing to Disclose

Malignant pleural mesothelioma (MPM) is a highly malignant and invariably lethal malignancy which has shown favorable increase in mean survival of patients who undergo trimodality therapy (extrapleural pneumonectomy (EPP), adjuvant chemotherapy and radiotherapy). To date, imaging findings of EPP have not been well described or compared with pneumonectomy (PN).

After obtaining institutional review board approval, a retrospective review of imaging findings on postoperative chest CT’s of 21 consecutive patients in whom EPP was performed were compared with 21 consecutive patients undergoing PN. Two independent observers evaluated multiple parameters including post pneumonectomy space (PPS) in short axis length, PPS in long axis, tissue (rind) thickness around PPS, mediastinal rind thickness, volume of hemithorax, density of fluid within PPS, concavity/convexity of the PPS, mediastinal shift, diaphragmatic herniation, tumor seeding, contralateral nodules and adenopathy. The T- and Mann-Whitney tests were used for statistical analysis to compare both groups of patients, and Kappa coefficients were determined for correlation between the two observers.

The rind thickness in the EPP vs PN groups was 8.5 mm (+/-5.1) and 4.4 (+/-3.7) ( p=0.002)respectively.. Mediastinal rind thickness in EPP vs. PN was 4.5 (+/-5.5) and 2.2 (+/-1.8) (p=0.066) respectively. The PPS short and long axes measured 74.4 (+/-19.9) and 142.+/-35.4 in EPP vs. 63.2 (+/-16.4) (p=0.037) and 153+/-22.0 (p=0.23) in PN patients. There was no statistically significant difference in the estimated volume loss, the convexity of the PPS, nodularity or unevenness of the rind, density of the fluid, and the degree of mediastinal shift. Kappa correlation overall was 0.66.

The major CT imaging finding in EPP is thickening of the rind of the PPS, which is of significantly greater thickness than the rind of tissue around the PPS in patients who have undergone PN.

This may be helpful to recognize when evaluating for recurrence of MPM.

Gill, B, Seely, J, Matzinger, F, Souza, C, Comparative Study of the Computed Tomography Findings Following Pneumonectomy and Extrapleural Pneumonectomy.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5013655.html