~(67)Ga scinitigraphy monitioring of therapy in Non-Hodgkin's lymphoma

Objective In early phase of therapy in Non Hodgkin's lymphoma (NHL), 67 Ga imaging was used to predict and monitor the therapeutic response. Methods In 86 patients with NHL proven by clinical syndrome and pathology and with positive 67 Ga imaging and CT scan before therapy, 67 Ga scintigraphy was performed after 2 and 4 cycles of therapy.CT scan was also performed after 4 cycles of therapy on 51 of the 86 patients.Average following time was 1.5 years (3～30 months).The therapeutic results were classified as:①complete remission (CR):the lesion uptake of 67 Ga was not detected;②partial remission (PR):the lesion uptake of 67 Ga was 50% less than that before therapy;③no remission (NR):the lesion uptake of 67 Ga was the same as or more than that before therapy. Results Based on 67 Ga imaging in 86 patients,61 patients were in CR after therapy,14 were in PR,and 11 were in NR.During the follow up,the negative predictive value (NPV) after 2 cycles of therapy was 90% (43/48),but negative predictive value after 4 cycles of therapy was 69% (9/13),suggesting that early NPV has more important significance.In PR and NR,NPV was only 36% (9/35).CT findings:in 51 patients undergone CT scan after therapy,18 were negative and 33 were positive.During the follow up,the NPV was 67% (12/18),the positive predictive value was only 27% (9/33).Statastical results showed that the 67 Ga imaging could effectively predict the therapeutic response ( P 0.001),but the CT could not ( P 0.05). Conclusions The early 67 Ga imaging after therapy may help confirm the presence of active NHL better than late 67 Ga imaging does;patients with PR or NR may have poor prognosis; 67 Ga imaging is better than CT in prediction and evaluation of therapeutic outcome in NHL.