Original Article
Impact of maximum standardized uptake value of non-small cell lung cancer on detecting lymph node involvement in potential stereotactic body radiotherapy candidates
Abstract
Background: The retrospective study investigated the association between the maximum standardized uptake value (SUVmax) of primary tumor and lymph node involvement in potential stereotactic body radiotherapy (SBRT) candidates.
Methods: A total of 185 patients with clinical stage I NSCLC were enrolled in the current study. All patients underwent lobectomy with systematic lymph node dissection following preoperative FDG-PET/CT scanning. The association between clinicopathological variables and lymph node involvement was analyzed by univariate and multivariate analysis. Spearman’s correlation test was used to evaluate the correlation between them. Receiver operating characteristic (ROC) analysis was performed to calculate the area under the curve.
Results: Among these patients, 22.1% had occult lymph node involvement, 15.1% were N1 and 7.0% were N2. Greater tumor size (P=0.007), elevated CEA (P=0.006), central location (P=0.002), higher SUVmax (P<0.001), solid nodule type (P=0.002), visceral pleural invasion (P=0.001) and presence of micropapillary and solid patterns (P=0.002) were significantly associated with lymph node involvement. In multivariate analysis, lymph node involvement was associated with central location (OR 5.784, 95% CI: 1.584–21.114, P=0.008), SUVmax (increase of 1 unite, OR 1.147, 95% CI: 1.035–1.272, P=0.009) and visceral pleural invasion (OR 3.044, 95% CI: 1.369–6.769, P=0.006). ROC area under the curve of SUVmax for lymph node involvement was 0.770 (95% CI: 0.698–0.841), the sensitivity and specificity were 85.4% and 63.2%, respectively. Spearman’s correlation test showed that SUVmax of tumor mostly depended on tumor size and nodule type.
Conclusions: SUVmax of primary tumor was a predictor of lymph node involvement for potential SBRT candidates. Centrally located tumor and visceral pleural invasion were related to higher rate of nodal metastasis. Lobectomy and systemic lymph node dissection should be performed in these patients, instead of SBRT.
Methods: A total of 185 patients with clinical stage I NSCLC were enrolled in the current study. All patients underwent lobectomy with systematic lymph node dissection following preoperative FDG-PET/CT scanning. The association between clinicopathological variables and lymph node involvement was analyzed by univariate and multivariate analysis. Spearman’s correlation test was used to evaluate the correlation between them. Receiver operating characteristic (ROC) analysis was performed to calculate the area under the curve.
Results: Among these patients, 22.1% had occult lymph node involvement, 15.1% were N1 and 7.0% were N2. Greater tumor size (P=0.007), elevated CEA (P=0.006), central location (P=0.002), higher SUVmax (P<0.001), solid nodule type (P=0.002), visceral pleural invasion (P=0.001) and presence of micropapillary and solid patterns (P=0.002) were significantly associated with lymph node involvement. In multivariate analysis, lymph node involvement was associated with central location (OR 5.784, 95% CI: 1.584–21.114, P=0.008), SUVmax (increase of 1 unite, OR 1.147, 95% CI: 1.035–1.272, P=0.009) and visceral pleural invasion (OR 3.044, 95% CI: 1.369–6.769, P=0.006). ROC area under the curve of SUVmax for lymph node involvement was 0.770 (95% CI: 0.698–0.841), the sensitivity and specificity were 85.4% and 63.2%, respectively. Spearman’s correlation test showed that SUVmax of tumor mostly depended on tumor size and nodule type.
Conclusions: SUVmax of primary tumor was a predictor of lymph node involvement for potential SBRT candidates. Centrally located tumor and visceral pleural invasion were related to higher rate of nodal metastasis. Lobectomy and systemic lymph node dissection should be performed in these patients, instead of SBRT.
