Parietal pleural invasion of lung masses: evaluation with CT performed during deep inspiration and expiration.

PURPOSE

To determine whether respiratory phase shift of lung masses at computed tomography (CT) indicates the absence of parietal pleural invasion.

MATERIALS AND METHODS

Helical CT was performed during deep inspiration and expiration in 17 patients with peripheral lung tumors in contact with the chest wall. Changes in the location of the tumor relative to a chest wall marker were noted.

RESULTS

Six of 10 lesions in the middle or lower lobes showed substantial respiratory phase shift; all were proved at surgery not to have invaded the parietal pleura. Three of the 10 showed no respiratory phase shift and were found at surgery to have invaded the parietal pleura. CT findings for tumors in the upper lobe did not correlate with the surgical findings.

CONCLUSION

The presence of respiratory phase shift is a reliable indicator of the lack of parietal pleural invasion for tumors in the middle or lower lobes.