Prognostic PET/CT is superior to CT for follicular lymphoma

A retrospective study gauging the benefit of PET/CT after first-line therapy for follicular lymphoma in multi-center trials puts PET/CT on a pedestal above CT alone as a tool for gauging patients’ response to therapy and prospective survival, according to a study published Sept. 18 in The Lancet Haematology.

Judith Trotman, MBChB, director of the clinical research unit in the haematology department of the Concord Cancer Centre at Concord Hospital, University of Sydney, Australia, and colleagues evaluated the scans of 439 patients between December 2004 and September 2010 to assess concordance with progression-free survival and overall survival. Results of the study indicated that PET/CT provided more useful information than CT for potential prognosis in follicular lymphoma.

“PET-CT rather than contrast-enhanced CT scanning should be considered as a new standard for response assessment of follicular lymphoma in clinical practice, and could help guide response-adapted therapy,” wrote the researchers.

Of the 439 patients reviewed, 249 received centrally reviewed post-induction scans. Of these 246 patients, a total of 41 had a positive PET scan, according to preset cutoff rates. The researchers conducted a pooled analysis of survival based on positive and negative scans at a median follow-up of about 55 months. About 23 percent of patients who tested positive on a PET/CT scan went on to remain cancer-progression free for four years, whereas about 63 percent of those who received a negative scan remained progression free for that four-year period.

Four-year overall survival was gauged at about 87 percent for those who tested positive vs. about 97 percent for those who received negative scans. CT was shown to be only “weakly predictive” of progression-free survival.