Nuclear medicine imaging in the detection of locally advanced laryngeal and hypopharyngeal cancer

Introduction. The choice of adequate treatment for cancer patients and their survival rates significantly depend on the precise detection of the primary tumor and the assessment of the extent of cancer involvement. Despite advances in the treatment of laryngeal/hypopharyngeal cancer, many aspects of this problem are still unresolved. The purpose of the study. Diagnostic capabilities of nuclear medicine imaging in the detection and assessment of the spread of laryngeal/hypopharyngeal cancer were studied. Material and methods. The study included 40 patients with histologically verified laryngeal/ hypopharyngeal cancer, 10 patients with tumor recurrence after completion of therapy and 20 patients with benign laryngeal lesions. Single photon emission computed tomography (SPECT) was performed 20 minutes after the injection of 99mTc-methoxy-isobutyl-isonitrile (MIBI). Sentinel lymph nodes (SLNs) were detected in 26 patients after submucosal injections of 99mTc-Tehnefit or 99mTc-Alotech around the tumor. In 18 hours after the injection of 99mTc-Tehnefit and 99mTc-Alotech, SPECT was performed. In 24 hours after the injection of 99mTc-Tehnefit and 99mTc-Alotech, intraoperative SLN detection was performed using Gamma Finder II. Results. SPECT with 99mTc-MIBI revealed laryngeal and hypopharyngeal tumors in 38 of the 40 patients. The 99mTc-MIBI uptake in metastatic lymph nodes was visualized in 2 (17 %) of the 12 patients. 28 SLNs were detected by SPECT and 31 SLNs were identified using the intraoperative gamma probe. The percentage of lymphotropic radiopharmaceuticals in the SLN was 5-10 % of the radioactivity in the injection site by SPECT and 12-33 % by intraoperative gamma probe detection. Conclusion. SPECT with 99mTc-MIBI is an effective tool for the diagnosis of laryngeal/hypopharyngeal cancer. The sensitivity, specificity and accuracy of this technique were 95, 80 and 92 %, respectively. The use of 99mTc-Tehnefite and 99mTc-Alotech for the detection of SLN in laryngeal/hypopharyngeal cancer patients was characterized by high efficacy, while intraoperative detection was more sensitive, being 80 and 100 %, respectively.