ABSTRACT
Objective:To explore the significance of 99Tc m-sulfur colloid lymphoscintigraphy in the diagnosis of lower limb lymphedema after gynecological tumor surgery. Methods:The clinical data of patients with lower limb lymphedema after gynecological tumor surgery in Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from May 2015 to October 2019 were retrospectively analyzed. 99Tc m-sulfur colloid lymphoscintigraphy was performed in all patients. The results of lymphatic vessel imaging, lymph node imaging and their combination in the diagnosis of lower limb lymphedema were analyzed. The diagnostic efficacy of lymphatic vessel imaging alone, lymph node imaging alone and their combination was evaluated by the receiver operating characteristic (ROC) curve and the area under the curve (AUC), and the Youden index, sensitivity and specificity were calculated. Results:Among the 100 lower limbs of 50 patients, 56 limbs had lymphedema and 44 limbs had no obvious edema. When diagnosis was based on abnormal lymphatic vessel imaging alone, among 56 lower limbs with lymphedema, lower limbs lymphatic vessel imaging was positive in 38 (67.9%) and negative in 18 (32.1%); among 44 lower limbs without obvious edema, lower limbs lymphatic vessel imaging was positive in 6 (13.6%) and negative in 38 (86.4%); the sensitivity was 67.9%, the specificity was 86.4%, and the Youden index was 0.543. When diagnosis was based on abnormal lymph node imaging alone, among 56 lower limbs with lymphedema, lower limbs lymph node imaging was positive in 42 (75.0%) and negative in 14 (25.0%); among 44 lower limbs without obvious edema, lower limbs lymph node imaging was positive in 13 (29.5%) and negative in 31 (70.5%); the sensitivity was 75.0%, the specificity was 70.5%, and the Youden index was 0.455. When diagnosis was based on the combination of lymphatic vessel imaging and lymph node imaging, among 56 lower limbs with lymphedema, lymphatic vessel imaging and lymph node imaging were positive in 48 (85.7%) and negative in 8 (14.3%); among 44 lower limbs without obvious edema, lymphatic vessel imaging and lymph node imaging were positive in 14 (31.8%) and negative in 30 (68.2%); the sensitivity was 85.7%, the specificity was 68.2%, and the Youden index was 0.539. The AUC for the combined diagnosis of lymphatic vessel imaging and lymph node imaging was 0.781, the AUC for the diagnosis of abnormal lymphatic vessel imaging was 0.771, and the AUC for the diagnosis of abnormal lymph node imaging was 0.739 (all P < 0.01). Conclusions:99Tc m-sulfur colloid lymphoscintigraphy is of great help in the diagnosis of lower limb lymphedema after operation of gynecological tumors. The combination of lymph node imaging and lymphatic vessel imaging is more effective in the diagnosis of lower limb lymphedema.
ABSTRACT
<p><b>BACKGROUND</b>An accurate pre-operative tumor staging is the premise for a successful operation, for which a non-invasive evaluation of the nature of lung nodules and the real extent of them is necessary. As the pioneer of functional images, nuclear medicine continues to introduce novel radiopharmaceuticals and new techniques for cancer imaging, including tetrofosmin (TF). The aim of this study is to evaluate the clinical usefulness of 99m Tc-tetrofosmin SPECT ( 99m Tc-TF SPECT) in the diagnosis of lung cancer and mediastinal lymph node involvement.</p><p><b>METHODS</b>Thirty-three patients with pulmonary neoplasms took both CT scan and 99m Tc-TF SPECT in one week before their operations or puncture biopsy. Then the sensitivity, specificity and accuracy were acquired according to the pathological outcomings and the results of 99m Tc-TF SPECT and CT were compared in detection of lung cancer and mediastinal lymph node metastasis, respectively.</p><p><b>RESULTS</b>The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 99m Tc-TF SPECT for lung cancer were 95.7%, 80.0%, 90.9%, 91.7%, 88.9%, and 73.9%, 70.0%, 72.7% , 85.0% , 53.8% by CT, respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 99m Tc-TF SPECT for mediastinal lymph node metastasis were 93.3%, 75.0%, 87.0% , 87.5%, 85.7%, while those of CT were 60.0%, 75.0%, 65.2%, 81.8%, 50.0% respectively. The sensitivity of 99m Tc-TF SPECT was significantly higher than that of CT for lung neoplasms (P < 0.05).</p><p><b>CONCLUSIONS</b>99m Tc-TF SPECT is a useful non-invasive presurgical tool to evaluate primary lung cancers and mediastinal lymph node involvement, and it will play a favorable clinical role in diagnosis and staging of lung cancer.</p>