The MRI scans were obtained with a Siemens MAGNETOM Verio 3-Tesla Magnetic Resonance Scanner (Siemens Medical Solutions, Inc., Germany) using the manufacturer-supplied anterior thoracic coil in a breath-holding technique with a slice thickness of 1.2 cm, a repetition time of 4.0 ms, a 30 degrees flip angle and spatial resolution of 1 × 1 × 2.5 mm. The images were obtained during free breathing.
We used the SWOG score50 to assess the clinical significance of biomarker discordance. As described in the SWOG study, a score of 0 or 1 indicates no recurrence or recurrence with complete and controlled resection, respectively, and a score of 2 or 3 indicates recurrence with incomplete and uncontrolled resection, respectively. In our analysis, 57% of patients (182 of 327) never recurred even when margin positive cases had no signs or symptoms of recurrence. A score indicating that the patient did not have recurrence indicated that the presence of positive margins is an independent risk factor for recurrence (HR, 2.97; 95% CI, 1.42 to 6.24) (P =.0047). These results were consistent with previous studies2,4,9,51,52 that have shown the effect of positive margins on disease recurrence. However, 7211a4ac4a