Positron emission tomography scanning in the setting of post-transplant lymphoproliferative disorders

Background: Post-transplant lymphoproliferative disorder (PTLD) is a serious complication of transplantation. We examined the role of positron emission tomography (PET) scanning in PTLD. Methods: All patients treated for PTLD from 2001-2006 who also underwent PET scans were reviewed. Results: Nineteen PTLD patients were included. Seventeen patients had PET scans for staging at diagnosis. Of these, two patients with primary central nervous system lymphoma and one patient with only bone marrow involvement after complete surgical resection of a bowel lesion had no abnormalities on CT or PET scan. The remaining patients had measurable, extracranial disease by CT scan and PET scan. The median maximum standard uptake value was 8.2 (range 3-30). Thirteen patients had a PET scan following treatment. Eleven of 13 patients had a complete response (CR). Two of 13 patients had persistent disease following therapy; in one of these patients, relapsed disease was documented by PET scan alone. Of the 11 patients with CR, three patients relapsed shortly thereafter. In each case, at the time of relapse, the PET scan confirmed recurrent disease regardless of histopathologic subtype. Conclusions: PET scans may have a role in the staging and follow-up of patients with PTLD. Additional prospective studies are warranted.