Gallium 67 imaging in monitoring lymphoma response to treatment

Abstract

The value of gallium 67 (Ga) imaging in monitoring lymphoma response to treatment was assessed in 25 patients with Ga-avid tumors and compared to body computed tomography (CT), chest radiographs, and palpation of tumor infiltrated peripheral lymph nodes. Ga imaging was negative in 95% (20/21) of the patients who were clinically considered to be in remission and in whom treatment was stopped. The disease did not recur during a follow-up of 12 to 26 months in 15 patients. Six patients developed recurrence of the disease 3 to 12 months after treatment was stopped. In all six patients Ga imaging became positive again at the time of the appearance of active disease. In the group of patients in remission, CT was negative in 57% (11/19), chest x-rays in 55% (6/11) and peripheral lymph nodes were palpated in none of the patients (13/13). In four patients that did not achieve remission after treatment, Ga scans were positive. Ga imaging appears useful in monitoring lymphoma response to treatment. This is probably because Ga imaging monitors tumor cell viability, whereas body CT and chest radiographs show the tumor mass, which may consist of fibrotic or necrotic tissue.

The usefulness of 18F‐fluorodeoxyglucose positron emission tomography (18F‐FDG‐PET) and a comparison of 18F‐FDG‐pet with 67gallium scintigraphy in the evaluation of lymphoma

“…However, gallium-67 scintigraphy ( 67 Ga) remains the most widely used nuclear tracer for evaluating lymphoma. [6][7][8][9] Although the mechanism of uptake of 67 Ga by lymphoma cells is not understood fully, its accumulation appears to depend in part on the density of the transferrin receptor (CD71) on tumor cells and the acidic condition of tumor tissues associated with anaerobic metabolism. [7][8][9] The major limitations of 67 Ga include relatively low sensitivity and accuracy, particularly for abdominal and extranodal sites.…”

“…In particular, it should be noted that the sensitivity of 67 Ga in FL and SMZL was low (33% and 31%, respectively). These results are concordant with the observation that the degree of 18 F-FDG or 67 Ga accumulation is associated with cell proliferation and histologic grade, 8,20,30 and they suggest that caution should be used in the staging of indolent lymphoma by 67 Ga. One of the striking results of the current study was that the sensitivity of 67 Ga in MCL and NK-nasal was extremely low, whereas 18 F-FDG-PET detected disease sites in these subtypes with high sensitivity, because these 2 subtypes are aggressive clinically and are resistant to conventional chemotherapy (combined cyclophosphamide, doxorubicin, vincristine, and prednisone). [31][32][33][34] There have been few studies on the sensitivity of 67 Ga in these subtypes.…”

“…The 1 reported patient with MCL demonstrated extremely low 67 Ga uptake. 8 Concerning MCL that previously was categorized as low-grade lymphoma, 31,32 this result may reflect biologic features in these subtypes and demonstrates the utility of 18 F-FDG-PET for these subtypes. Currently, however, the precise mechanism in these lymphoma subtypes is uncertain.…”

“…[6][7][8][9] Although the mechanism of uptake of 67 Ga by lymphoma cells is not understood fully, its accumulation appears to depend in part on the density of the transferrin receptor (CD71) on tumor cells and the acidic condition of tumor tissues associated with anaerobic metabolism. [7][8][9] The major limitations of 67 Ga include relatively low sensitivity and accuracy, particularly for abdominal and extranodal sites. 4,10 One of the important roles of 18 F-FDG-PET and 67 Ga is initial staging and monitoring of residual disease and recurrence after treatment.…”

Comparison of fluorine‐18 fluorodeoxyglucose positron emission tomography and Ga‐67 scintigraphy in evaluation of lymphoma

“…Although there has not been a comprehensive study comparing FDG-PET and Ga-67 scintigraphy, previous studies with a limited number of patients have reported sensitivities ranging between 94% and 100% in the detection of disease sites in lymphoma for FDG-PET and between 85% and 90% for Ga-67 imaging. 7,8,15,26 Although the site sensitivity for Ga-67 in our study is lower than previous reports, the patient sensitivity is consistent with these prior studies. Neoplastic tissues utilize glycolysis to meet their energy needs because of limited oxidation of intracellular metabolites.…”