Ground-glass attenuation in nodular bronchioloalveolar carcinoma: CT patterns and prognostic value.

PURPOSE: The purpose of our study was to assess the CT patterns and prognostic value of ground-glass attenuation in nodular bronchioloalveolar carcinoma (BAC).

METHOD: We retrospectively reviewed CT examinations of 22 patients with 24 nodular BACs who underwent surgery. CT and pathologic findings were analyzed and correlated with postoperative course of disease.

RESULTS

We detected five patterns of ground-glass attenuation associated with nodular BAC: pure ground-glass nodule (n = 1), ground-glass nodule with superimposed lymphangitis (n = 1), nodule with mixed areas of ground-glass attenuation and consolidation (n = 2), ground-glass halo around nodule (halo sign) (n = 3), and nodule associated with a plurisegmental area of ground-glass attenuation (n = 1). Two patients with the halo sign and a third patient with a plurisegmental area of ground-glass attenuation rapidly developed diffuse pulmonary disease by bronchogenic spread and died a few months after surgery.

CONCLUSION

Our series demonstrates that focal BAC may progress to diffuse pulmonary involvement by bronchogenic spread. The presence of a large area of ground-glass attenuation associated with a nodular BAC might be the CT sign of an aggressive biologic behavior. In these cases there is a high likelihood for diffuse disease to develop from bronchogenic spread.