The relevance of somatostatin receptor expression in malignant lymphomas.

Somatostatin (SRIF) receptor (sst) expression on lymphoid cells may be related to activation or proliferation of these cells. We investigated the effectiveness of sst scintigraphy in the staging of malignant lymphomas compared with conventional methods. One hundred twenty-six patients with newly diagnosed, histologically proven malignant lymphoma (54 with Hodgkin's disease [HD] and 72 with non-Hodgkin's lymphoma [NHL]) received 111In-labeled DTPA-octreotide (> 200 MBq 111In) and were assessed by planar total-body scintigraphy and single-photon emission computed tomography (SPECT) images of the upper abdomen. The sst scintigraphy was positive in 98% of HD patients. Compared with conventional methods, additional lymphomas were detected in 37%, while lesions escaped detection in 7% (all located in the abdomen); 10 HD patients were downgraded and one was upgraded. The sst scintigraphy was positive in 85% of NHL patients, but positivity did not correlate with the degree of malignancy. Additional lesions were detected in 21% of NHL patients, with false-negatives in 7% and upgrading in 13 NHL patients. The results indicate that sst scintigraphy is sensitive in patients with HD and NHL and may reveal sites of active disease undetected by conventional methods, making it a useful diagnostic tool for malignant lymphomas. Further studies should define its value in clinical management.