OBJECTIVETo investigate the value of multislice spiral computed tomography (MSCT) in demonstrating the relationship between bronchus and peripheral lung cancer.

METHODSWe prospectively performed volumetric targeted scans of 0.5 mm collimation with MSCT and reconstructed images of multiplanar reconstruction (MPR), curved multiplanar reformations (CMPR) and surface shaded display (SSD) in 53 peripheral lung cancers. The results were compared with macroscopic and microscopic specimens.

RESULTS(1) The third- to seventh-order branches of the bronchi were clearly shown in all patients by the designed protocol. CT demonstrated the tumor-bronchus relationship in 29 (96.7%) adenocarcinomas and 13 (76.5%) squamous-cell carcinomas. Statistic analysis showed that there was no significant difference between the two groups (chi(2) = 2.8, P > 0.05). (2) The tumor-bronchus relationship was identified as four types with MSCT. Type I: bronchus was obstructed abruptly by the tumor, type II: bronchus penetrated into the tumor with tapered narrowing and interruption, type III: bronchus lumen shown within tumor was patent and intact, type IV: bronchus ran at the periphery of the tumor with intact or narrowed lumen. (3) Type I was shown in 31 of 53 (58.5%) tumors with squamous-cell carcinoma slightly more common than adenocarcinoma. Type II and type III were seen equally in 8 of 53 (15.1%) tumors which occurred only in adenocarcinomas. Type IV was seen in 15 of 53 (28.3%) tumors with adenocarcinoma being slightly more frequent than squamous cell carcinoma. (4) The tumor at the fourth-order bronchus was more common in squamous cell carcinoma, whereas that at the fixth-order bronchus was more likely in adenocarcinoma.

CONCLUSIONVolumetric targeted scan of ultra-thin section with MSCT and followed by MPR, CMPR and SSD reconstruction can greatly improve the manifestation of the bronchioles and accurately demonstrate the patterns of tumor-bronchus relationship, thereby reflecting pathologic changes to some extent.