OncLive today...12/18/12. Dr Cristofanelli provides supportive data on CTC's as a complementary clinical tool with some discussion on CTC counts and predicting bone mets progession. Some discussion on OS...
"Cristofanilli also discussed the role of CTCs in measuring progression, where enumeration has proven beneficial as a complement to imaging (Clin Cancer Res. 2006;12:6403-6409). Researchers have looked into the question of whether patients with 5 CTCs will progress faster, and found it to be “a very good determination of progression,” he said, particularly in visceral metastases.
Presenting new data on studies of patients (N = 146) with oligometastatic disease, Cristofanilli noted that typically these patients do better in terms of OS, but patients with 5 CTCs do worse. Researchers found a statistically significant difference in time to new metastatic sites for oligometastatic patients with 5 CTCs. Median survival was 40.2 months for patients with
Interesting article. No discussion though of how drug induced changes in CTC may or may not influence outcome and that is where the emphasis needs to go if one is looking for CTC count as a possible surrogate endpoint. Did mention that baseline CTC was not outcome predictive in patients treated with Avastin. Not sure how to interpret that.
So far the CTC guys have focussed on that seemingly important 5 cell/7.5 ml count and on 30% reductions in CTC as relevant. I believe those are the endpoints being tested in the Comet trials. Those may or may not be the best measures, but sometimes a compromise plan carried out to completion is better than lengthy searching and optimizing to get the best end result.
"Did mention that baseline CTC was not outcome predictive in patients treated with Avastin. Not sure how to interpret that."
Given bevacizumab's noteworthy toxicities in BC, I was driven to consider Wildbiftek's continued benefit vs.toxicity cautions immediately. It's unfortunate that the OncLive interviews are often too skeletal to provide much more than food for thought.
Each time I find new research into CTC prognostics, I feel reinforced - and compelled to make note, just in case that particular dataset be the straw to break the camel's back. With such a bounty of credible information, separating the wheat from the chaff is a vigil.
Ernie, you managed to solicit all my daily platitudes...