Objective: 67Ga scintigraphy has a well-documented role in nodal lymphoma for both disease staging and assessment of treatment response. The objective of the present study was to examine the role of 67Ga scintigraphy in diagnosis and assessment of treatment response, in patients with extranodal malignant lymphoma.
Methods: Seventy-one patients with extranodal malignant lymphoma were studied. Whole body scans in all and SPECT scans in some selected patients were performed 72 hours after injection of 67Ga-citrate. The influence of tumor site, histological classification and tumor size on 67Ga scintigraphy sensitivity was analyzed. Twenty-one of the seventy-one patients also had a second 67Ga scintigraphy to assess response to treatment.
Results: The overall 67Ga scintigraphy sensitivity was 83.1% (59/71). The sensitivity was low in patients whose extranodal lymphoma occurred in skin (0/3) and urinary bladder (0/1), as compared to other tumor sites. According to the histological classification of the lesion, the sensitivity was lower in low-grade than in intermediate and high-grade lymphoma. According to the tumor size, the sensitivity was low in lesions less than 2 cm in diameter than those more than 2 cm in diameter. The results changed from positive to negative accumulation in 20 (95.2%) of the 21 patients who had 67Ga scintigraphy to assess the response to treatment. These 20 patients showed a good clinical course.
Conclusions: Although 67Ga scintigraphy did not show positive accumulation in patients with skin and urinary bladder lymphoma, it was helpful to confirm the diagnosis and to evaluate the therapeutic effect in most patients with extranodal malignant lymphoma.