PET Scans for Follicular Lymphoma

From the journal Annals of Oncology comes the study "The Prognostic Role of Post-Induction FDG-PET in Patients with Follicular Lymphoma: A Subset Analysis from the FOLL05 Trial of the Fondazione Italiana Linfomi (FIL)."

(I'm guessing that sounds much nicer in Italian: Il ruolo prognostico di post-induzione FDG-PET in pazienti con linfoma follicolare: un sottoinsieme di analisi dalla prova FOLL05 della Fondazione Italiana Linfomi (FIL).  Say it slowly, while holding a glass of chianti and wiggling one eyebrow seductively. It is much nicer, isn't it?)

The study focused on the value of PET scans, compared to CT scans, in determining if a patient who had been treated was getting worse. This study is part of a larger Italian study of Follicular Lymphoma that has been looking at the effectiveness of Rituxan + CHOP, CVP, or FM. The researchers looked at 202 patients who had been given a PET scans three months after they were finished with their first treatment.

They found that the PET scans did a much better job then the CT scans. 15% (22 out of 145) of patients with a complete response (CR) after their CT scan were found to actually have only a partial response (PR) after the PET. On the other side, 53% (30 out of 57) of patients that were deemed PR after the CT scan were considered CR after the PET.

They then followed up with those patients for almost 3 years, and found that 66% of those who had been labeled as having a CR did not have their lymphoma return, while only 35% of those with a PR managed to keep their lymphoma from progressing. Thus, PET scans can be seen a prognostic tool -- a way of predicting whether or not it will progress over time. The authors recommend that PET scans become a required part of determining whether or not a patient has responded to treatment.

Interesting results, and it will be interesting to see how the lymphoma community responds. The CT vs. PET question has been thrown around for quite some time; both types of imaging have their limitations, and there are cost/benefit arguments that have to take place, too. (See Lymphomation.org for their (as usual) excellent discussion of PETs.]

Maybe we're leaning toward PET scans being worth it? ASH also featured a presentation this year on the benefits of PETs for Follicular Lymphoma after first-line Rituxan-containing treatments. It was similar to this Italian study in some ways, though not completely parallel. Still, the results also came down in favor of using PET scans as a prognostic tool. Maybe the two studies together will make a difference.

It's hard for me to get too emotionally invested in using PET vs CT. My own oncologist has favored CT scans, and while I haven't had a scan in a few years,  the CT seemed to work just fine. But the numbers certainly favor taking a harder look at the value of PETs for Follicular Lymphoma.