Finally!!!!! a paper showing which tumor markers (and serum her2ECD test) are best at

[Lani]

discovering recurrence early, determining if treatment worked/working and with specificity statistics even. And stats subtype specific, even! Most oncologists do not want to use CEA, CA and serum her2 as they say "they don't mean anything" or "we don't know what they mean" or "they can bounce all around and not reflect what the cancer is doing and can also miss a recurrence"

Although the sensitivity of each test individually are in the 32-50% percent range, the combination of all 3 performed in the group in which these are most accurate (the her2+ group...yeah!) is around 67% and waiting for a recurrence to become macroscopic and measurable to start a new regime can let the tumor bulk up so much of it is anaerobic, unavailable to the blood supply so the new treatment can't get to it, and allows many different additional mutations to develop/clones to take over so the next treatment will have a harder time keeping it under control.

Let's spread word about this one as my guess is they are going to need larger studies, multiinstititional etc before guidelines and practice are changed. NICE may decide 60-60% isn't cost effective, etc. This is where, in my opinion, advocates can be helpful as they can "get in the face" of those who determine the guidelines and remind them that some flesh and blood humans personally have something at stake here.

Let's get those larger studies done quickly and...if they pan out...work to get the guidelines changed. It seems the group where determining if utilizing these markers and changing treatment, adding additional early imaging may make a difference will be most clear and beneficial will be....the her2+ group.

The serum her2 ECD test is going off patent. Don't know if that means that it will be more widely done or performed more cheaply
(when was the last time you remember a test being done more cheaply?) but perhaps we can get its use to be more widespread.

Now an oncologist will probably say that since the sensitivity is only 50-60% why should they change treatment if the tests are positive? I bet they could get stats regarding if the tests are positive two or three times in a row over an x week period the specificity/sensitivity goes way up with each time it stays that way and similarly, having elevating tumor markers should be a reason to retest whether that means PET/CT, CTCs, CHEST CT, BRAIN MRI, abdominal MRI or bone scan. These tests have been shown NOT to be cost effective when done when the patient is first diagnosed, but would be when tumor markers are rising IF catching the recurrence, biopsying the recurrence and changing treatment early make a difference in overall outcome. It seems intuitive that it would, but oncologists/bean counters won't change their approach until a large multiyear study demonstrates number they can quote. It seems to me those numbers will be easiest to get with her2+ bc as there are now a large number of treatments proving effective in contrast to her2= breast cancers.

As regards the sensitivity, here too, serum her2 ECD should excel in her2+ bc patients.

This has been one of my rare opinion posts. Usually I just post information.

Anyone else want to chime in?

Here it is:

Clin Chem Lab Med. 2013 Feb 13:1-9. doi: 10.1515/cclm-2012-0488. [Epub ahead of print]
Sensitivity of CA 15-3, CEA and serum HER2 in the early detection of recurrence of breast cancer.
Pedersen AC, Sørensen PD, Jacobsen EH, Madsen JS, Brandslund I.
Abstract
Abstract Background: The aim of this project was to investigate the sensitivity of CA 15-3, CEA and HER2 in the early diagnosis of metastatic breast cancer. Methods: Serial serum values of CA 15-3, CEA and HER2 were determined in 107 patients with recurrence after breast cancer. Fifteen of the patients had primary disseminated disease, nine patients only developed local recurrence during the follow-up period and the remaining 83 developed distant metastases. Results: In the group of patients with distant metastatic disease (n=83), elevated serum levels of CA 15-3 (>32.4 U/mL), CEA (>2.5 µg/L for non-smokers and >10 µg/L for smokers) and HER2 (>15 µg/L) were found in 49.4%, 38.6% and 32.5%, respectively, at the time of diagnosis of recurrence. CA 15-3 was significantly better than HER2 (p=0.027). The most sensitive combination was obtained using CA 15-3/CEA (60.2%) or CA 15-3/HER2 (57.8%). Combining all three tumour markers raised the sensitivity to 63.9%. In the subgroup of patients with tissue HER2+ tumours, the sensitivity of HER2 increased to 55.6%. The best combination in this group was CEA/HER2 (66.7%). In the subgroup of patients with tissue HER2- tumours, CA 15-3 was significantly better. The best combination was CA 15-3/HER2 or CA 15-3/CEA with a sensitivity of 55.8% and 59.6%, respectively. Conclusions: The combination of several tumour markers enhances the sensitivity for detection of metastatic breast cancer. We recommend HER2 or the combination of CEA and HER2 in tissue HER2+ and CA 15-3 or the combination of CA 15-3 and CEA in tissue HER2-.
PMID: 23403727