rising tumor markers - confused

I have bone mets & was on fasoldex/herceptin/zometa for 6 months last year. PET scan 12/03 showed more tumor activity & my ca2729 was up to 41 (from staying in the 'normal' range for several months. So I started chemo (navelbine) in January. Each month my ca2729 has continued to rise: 55, 67, 74, 82 ... not big jumps, but a definite trend. PET scan on 3/29/04 showed no visible bone lesions (great news), but with the caveat that there was diffuse activity in most bone marrow areas, which they say is due to the effects neupogen shots I have to give myself each week to keep my wbc up. The report said these diffuse areas may prevent seeing bone lesions. So, my onc. is confused; PET scan results & tumor markers results are giving opposing info. I'm to have 3 more treatments of navelbine, then 2 weeks with no treatment or neupogen. Then have another PET scan 2 weeks after when the shadowy effects should be out of my system, so the PET should be more clear. Until then I feel like I'm on pins & needles. My onc. says he puts lots more value on the scans, doesn't want to change treatment on a less specific tumor marker test, but can't explain away the rising counts either since it's a definite rising trend.

I forgot to ask my onc, can rising markers indicate brain mets? I had a normal brain mri 6 months ago.

Are there other explanations?

Thanks. Pam

perhaps in this setting, an mri might be more specific. while the PET is good for screening, it is not always specific. Maybe pick the area that has the most PET activity and do an MRI?

Rose, Good suggestion, but right now I don't think there is an identified area of "most activity" to focus on an MRI.

My sister - who was disgnosed stage III, her +++ in November has been on chemo + herceptin and the markers started to rise 89, then retested at 93 - about 2 months ago. Went thorugh the whole round of scans / MRI - everything and nothing showed. Doctor finally concluded that the markers were unreliable for her case. There are other possible explanations for rising markers (other medical conditions) - and she did have a health issue then.

I read somewhere else (I'm not sure if true - perhaps someone can confirm) - that brain met won't affect marker due to the blood brain barrier.

The marker results are not enormously high for you - I think that I've heard in the 800 range or higher - as a possability with activity.

Hang in there.