Unifying the predictive value of pretransplant FDG PET in patients with lymphoma: a review and meta-analysis of published trials.

Purpose: The predictive value of (18)F-FDG PET in patients with relapsing/refractory lymphoma who are receiving high-dose chemotherapy and autologous stem cell transplantation(ASCT) remains a matter of debate. Seminal reports on pretransplant ASCT indicated an adverse prognosis in patients with positive FDG PET scans. The lack of a uniform outcome measure along with the mixed histologies in various studies have hampered efforts to quantify this prognostic value.

Methods: A MEDLINE review of published trials up to April 2009 identified 16 studies involving pretransplant FDG PET scans in lymphoma. Where progression-free survival (PFS) and overall survival (OS) were set as themain outcome measures, time-to-event data analysis was used to calculate the overall prognostic value of a pretransplant FDG-PET scan.

Results: Pooled survival data from seven eligible studies suggested a worse PFS in patients with a positive FDG PET study (HR 3.23, 95% CI 2.14 to 4.87). The OS pooled from six eligible studies was also significantly worse among patients with a positive FDG PET study (HR 4.53, 95%CI 2.50 to 8.22). No statistically significant heterogeneity was observed between studies for either outcome.

Conclusion: Despite the documented clinical heterogeneity between studies, meta-analysis data confirmed the prognostic impact of pretransplant FDG PET in patients with lymphoma and provided a uniform measure of the association for both progression and survival after ASCT.