PET/CT Bests Conventional CT in Predicting Survival in Follicular Lymphoma

According to an analysis of a trio of studies, PET/CT is superior to conventional contrast-enhanced CT when it comes to measuring response to treatment and predicting survival in people with advanced-stage follicular lymphoma.

The study authors believe that their results indicate that PET/CT ought to be the new standard for response assessment in these patients. They also believe it could be used to help guide response-adapted therapy.

The study investigated the association between PET/CT status and survival among patients with advanced follicular lymphoma and was carried out by Judith Trotman, MBChB, associate professor in the department of hematology at Concord Hospital at University of Sydney in Australia and colleagues.

The pooled analysis included three multi-center studies with a total of 246 patients who had completed induction therapy of at minimum six cycles of rituximab plus chemotherapy. Participants then underwent PET/CT and conventional CT imaging within 3 months of their last dose of induction rituximab.

Median follow-up was 54.8 months.

Forty-one (17 percent) patients had positive post-induction PET scans. These patients were significantly less likely to achieve 4-year progression-free survival (PFS-- 23.2 percent vs. 63.4 percent) or 4-year overall survival (OS-- 87.2 percent vs. 97.1 percent). The 83 percent of patients with a negative post-induction PET scan experienced median PFS of more than 6 years; the 17 percent with a positive post-induction PET scan had median PFS of 17 months.

The research team was able to conclude that the predictive power of PET status was considerably stronger than — and independent of — that of conventional CT.

"Our study shows that PET/CT is much better in evaluating treatment response and is an early predictor of survival,” said Trotman in a press release. "This greater accuracy will assist physicians to more effectively monitor their patients. We expect this research will result in PET/CT imaging replacing CT, becoming the new gold standard to evaluate patients with follicular lymphoma after treatment. Importantly, it will be a platform for future studies of response-adapted therapies aimed to improve the poor outcomes for those patients who remain PET positive."

They reported their findings in the journal Lancet Haematology.

Source: Healio