Monday, May 15, 2017

Impact of Treatment in Long-Term Survival of FL

The journal PLOS ONE just published an article called "Impact of Treatment in Long-Term Survival Patients with Follicular Lymphoma: A Spanish Lymphoma Oncology Group Registry." As the article title implies, it looks at FL patients from a lymphoma registry in Spain, and tries to assess factors related to long-term survival.

I'll be honest -- I've kind of struggled with this article. I've read it over a few times, and I'm still not sure what to get out of it. I thought about just not writing about it (I'd rather do that than write something I wasn't comfortable with), but I decided the things that I do understand are important, and the lesson I get is worth sharing.

The study looks at a large group of 1074 Follicular Lymphoma patients in Spain who were diagnosed between 1980 and 2013. But it also looks at a smaller group of those patients who were still alive over 10 years after they were diagnosed, to see what those patients had in common.

There is a lot of statistical analysis in the article (which might be one of the things that gives me trouble), but the important statistic (mentioned in the title) is Overall Survival.

Looking at their large sample of 1000+ patients, they found that the Overall Survival was over 20 years.

If nothing else, that is important: OS for this group was over 20 years.

To give that some context, when I was diagnosed 9 years ago, I read that the OS was 8-10 years. That actually was probably low -- it might have been 12-15 years at best. But for this group, it was over 20 years. As a whole, Follicular Lymphoma patients are living longer. That should give us all something to celebrate.

Now, researchers tried to answer the question "Why do some patients live longer than others?"

To do this, they looked at 166 patients in their study who had been diagnosed over 10 years ago and were still alive. It's an important grouping. The larger study involved patients who were diagnosed before Rituxan was introduced in Spain (in 2004), and we know that Rituxan has played a HUGE role in making our lives better. So looking at more recent patients who have had long-term success makes a lot of sense.

They looked at a bunch of stuff to try to figure out what makes these patients have a longer OS. They found that the following were statistically significant:stage
  • age under 60 years at diagnosis
  • low FLIPI (they used FLIPI, and not FLIPI2 or m7-FLIPI, which are much newer)
  • normal Beta2 microglobulin (found in blood -- higher than normal levels are bad)
  • no B symptoms at diagnosis (things like fever and night sweats that might indicate a more aggressive form of FL)
  • combines treatments with Rituxan and anthracyclines (the patient had R-Chop or R-Bendamustine)
So, statistically, patients who survived more than 10 years were more likely to have had one or more of those things.

But let's keep things in perspective -- those are statistical measures only, and don't predict an individual patient's disease or survival.

And to me, none of them are very surprising. Low FLIPI and  lower stage are, by definition, measures of a less aggressive FL. Same with no B symptoms and normal Beta2 microglobulin. These things are not news.

What I did find interesting was some of the factors that do NOT correlate with longer Overall Survival:

  • gender
  • number of nodal areas affected (more isn't necessarily bad)
  • bone marrow involvement
  • origin (whether it started in lymph nodes or organs)
  • LDH levels (lactate dehydrogenase -- high levels are a problem)
  • presence of bulky mass (nodes are really big)
  • or transformation to an aggressive lymphoma
That first group included a bunch of things that I expected to be there. But this group includes things that I didn't expect to be there. The big lesson, for me as a patient, is to be really careful looking at statistics.

I've said before that I'm not a big fan of statistics. Every time my disease has gotten me depressed, it's because I focused too much on statistics, and where my place was within those numbers. And these statistics are a good explanation of why that happened.

It would be easy for someone to look at that first list and think they were in trouble, maybe regretting that they decided to watch and wait or take just Rituxan instead of R-CHOP. Or that their FLIPI score was too high. But, again, those things don't really tell us anything about an individual patient.

When I do look at statistics, I try to focus on the good numbers -- the things that make me happy. That's probably not fair, and it certainly isn't the way a statistician or scientist would do things. Fortunately for me, I am not a statistician or scientist, so I can look at numbers any way I want.

And the good number in this study says that our Overall Survival is trending up. People with Follicular Lymphoma are living longer with their disease. That's something we should all be hopeful about.

And the title of this article tell us why -- it's about the impact of treatment. Rituxan seems to be the common factor here, though they also tie it to Rituxan + chemotherapy. But again, the big lesson  here: Treatments are getting better. And they'll keep getting even better.

As I said, there's a lot more that could be analyzed in this study, I know. there's more to it than just saying we're living longer. Adn if anyone wants to point out other lessons to be learned, please do so.

But I'm sticking with what makes me happy. It's what I need today.


John said...

Bob, as always, thanks for posting this kind of information. Been having some down days lately, and you have a way of presenting everything with the "right" perspective. I'm also thankful not to be a statistician or scientist ;)

Lymphomaniac said...

John, thank you for the comment. I'm glad I can help. And sorry you're having some down days. I hope things pick up soon.