Comparison between preoperative versus intraoperative injection of technetium-99 m neomannosyl human serum albumin for sentinel lymph node identification in early stage lung cancer

Purpose. We aimed to evaluate the results of sentinel lymph node mapping according to injection time (preoperative vs. intraoperative) of technetium-99m neomannosyl human serum albumin ( ^99mTc-MSA) in patients with lung cancer. Methods. Data of 82 patients (55 men; mean age 62.9 ± 9.3 years) who were candidates for lobectomy with mediastinal lymph node dissection for clinical stage I non-small cell lung cancer were retrospectively reviewed. ^99mTc-MSA was administered at the peritumoral region under chest computed tomographic guidance, 1 to 2 h before surgery (preoperation group, n = 48) or soon after thoracotomy (intraoperation group, n = 34). Results. Patients' demographic data, except type of operation, did not differ between the two groups. Sentinel lymph nodes were detected in 46 patients (95.8%) in the preoperation group and 33 patients (97.1%) in the intraoperation group (P = .243). The mean number of sentinel nodes per patient was 2.1 in the preoperation group and 2.6 in the intraoperation group (P = .068). No falsely negative sentinel nodes were detected in any of the 17 patients with N1 or N2 disease (0%) in either group. Administration of the intraoperative injection could save additional cost (US$607) and time (70 min) in each patient. Conclusions. Sentinel node identification using ^99mTc-MSA appears to provide similar excellent results in both preoperative and intraoperative injection. Therefore, intraoperative injection of ^99mTc-MSA may be preferred as a result of lower cost and less waste of time.