THE FIRST EXPERIENCE OF USING 99MTC-1-THIO-D-GLUCOSE FOR SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY IMAGING OF LYMPHOMAS

Introduction. The purpose of this study was to evaluate the feasibility of using 99mTc-TG SPECT in the detection and staging of malignant lymphoma.Materials and methods.Fifteen patients with newly diagnosed malignant lymphoma underwent 99mTc-TG SPECT. Six patients had Hodgkin’s lymphoma and 9 patients had aggressive forms of non-Hodgkin’s lymphoma (NHL): diffuse large B-cell lymphoma (7 cases), B-cell follicular lymphoma (1 case), and lymphoma from B cells in the marginal zone (1 case). Stage IIA was diagnosed in 5 patients, stage IIB in 1, stage IIIA in 1, stage IVA in 4 and stage IVB in 4 patients.Results.Pathological 99mTc-TG uptake in lymph nodes was observed in 14 (93 %) of the 15 patients. In one patient, the enlarged submandibular lymph node (16 mm in size) detected by CT was not visualized by 99mTc-TG SPECT. This false-negative result was likely to be associated with increased accumulation of 99mTc-TG in the oropharyngeal region. There were difficulties in the visualization of paratracheal, para-aortic and paracardial lymph nodes. These difficulties were associated with a high blood background activity, which persisted even 4 hours after intravenous injection of 99mTc-TG. Software-based SPECT and CT image fusion allowed visualization of these lymph nodes. The pathological 99mTc-TG accumulation in axillary, supraclavicular, infraclavicular and cervical lymph nodes was observed most often. Extranodal involvement was seen in 9 patients. 99mTc-TG SPECT identified extranodal hypermetabolic lesions in 7 (78 %) of these patients. In one patient, hypermetabolic lesion in the lung detected by 99mTc-TG SPECT was not detected on CT image. CT identified bone marrow involvement in the pelvic and scapula in 1 patient. The use of 99mTc-TG SPECT allowed the visualization of hypermetabolic bone tissue lesions in this patient (Figure 4). In addition, in a patient with intact bone tissue on CT, 99mTc-TG SPECT detected hypermetabolic lesions in the iliac bone.Conclusion.99mTc-1-Thio-D-glucose demonstrated increased uptake in nodal and extranodal sites of lymphoma. The results indicate that SPECT with 99mTc-1-Thio-D-glucose is a feasible and useful tool in the detection and staging malignant lymphoma.