Maximum standardized uptake value of the primary tumor does not improve candidate selection for sublobar resection

Objective: This retrospective study examined whether adding the maximum standardized uptake value of a primary tumor to the consolidation-to-tumor ratio from a high-resolution computed tomography scan can improve the predictive accuracy for pathological noninvasive lung cancer and lead to better patient selection for sublobar resection.

Methods: We included 926 patients with clinical stage IA non-small cell lung cancer. Pathological noninvasive cancer (n = 515) was defined as any case without lymphatic invasion, vascular invasion, or lymph node metastasis. The prediction accuracies of maximum standardized uptake value and consolidation-to-tumor ratio were evaluated using receiver operating characteristic curves and area under the curve.

Results: For consolidation-to-tumor ratio or maximum standardized uptake value alone, the area under the curves were 0.733 (95% confidence interval, 0.708-0.758) and 0.842 (95% confidence interval, 0.816-0.866), respectively. When the consolidation-to-tumor ratio and maximum standardized uptake value were combined, the area under the curve was 0.854 (95% confidence interval, 0.829-0.876). However, to obtain a predictive specificity of 97%, sensitivity needed to be 42.5% for the consolidation-to-tumor ratio, 38.3% for the maximum standardized uptake value, and 45.0% for these 2 in combination.

Conclusions: Our results suggest that despite the high area under the curve for maximum standardized uptake value, caution is needed when using maximum standardized uptake value to select candidates for sublobar resection. We found that a low maximum standardized uptake value did not mean the tumor was a pathological noninvasive lung cancer. Therefore, using consolidation-to-tumor ratios from high-resolution computed tomography to decide whether sublobar resection is appropriate for patients with clinical stage IA non-small cell lung cancer is better than using maximum standardized uptake value when setting specificity to a conservative 97% for predicting pathological noninvasive lung cancer.