A Study About The Value Of Relationship Between SPN And Bronchus In Determining The Nature Of SPN

Objective: To evaluate the type between solitary pulmonary nodule (SPN) and bronchus and its value in predicting the nature of nodule.Methods:We collected retrospectively 66 SPN cases with diagnose clearly,51 cases had histological diagnosis by operation or thoracoscope,13 cases unchanged during follow-up between January 2007 and August 2009,2cases cured by drug treatment. All patients were scaned by multislice spiral computed tomography (MSCT) and the images were post-processing in the workstation using multiplanar reformation (MPR) to show SPN-bronchus relationship from various angles. The patterns of the SPN with related bronchus were analyzed and compared with microscopic specimens.66 SPN included 37 malignant tumors and 29 benign tumors.Results:(1) The SPN-bronchus relationship was positive in 51 of 66. The 51 including 33 malignant nodules and 18 benign nodules, positive rate 89.2%(33/37) and 62.1%(18/29) respectively. There are statistically significant difference (P＜0.01). (2) The SPN-bronchus relationship was classified into five types: TypeⅠ:the bronchus was obstructed abruptly at the edge of SPN; TypeⅡ:the bronchus penetrated into SPN with tapered narrow and interruption; TypeⅢ:the bronchus running through the whole SPN; TypeⅣ:the bronchus run at the periphery of SPN nodules; TypeⅤ:the bronchi are converging on the tumor. (3) The cases with SPN-bronchus relationship showed as follow: TypeⅠ:20 cases, including 13 malignant and 7 benign tumors; TypeⅡ:22cases, including 19 malignant and 3 benign tumors; TypeⅢ:9cases, including 8 malignant and 1 benign tumors; TypeⅣ:19cases, including 10 and 9 respectively; TypeⅤ:17cases, including 15 malignant and 2 benign tumors; In TypeⅡthe positive rates were 51.4%and 24%respectively in malignant and benign group, there are statistically significant difference between malignant and benign group (P＜0.01); In Type V, the positive rates were 40.5% and 7% respectively in malignant and benign group, there are statistically significant difference between malignant and benign tumors (P<0.01). (4) Most malignant nodules commonly showed typeⅡand typeⅢ, proved by pathology, and most are adenocarcinomas (24cases), only 3 cases are squamous carcinomas. Benign nodule appeared in all type, however, TypeⅡand TypeⅢwere less (4/29,13%).Conclusion: MSCT volume scan and MPR can show clearly the relationship between the SPN and bronchus; Certain patterns of SPN-bronchus may reflect definite pathologic change of SPN; The relationship is valuable in determining the nature of differentiation of SPN.