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Becky · 09-27-2007, 07:30 PM

The CA 27/29 measures a protein that cells make but cancerous tumors make more of. This is why everyone (to include those who never had cancer) would get some type of positive number.

The Her2 Serum test tests for the cleaved external part of the Her2 receptor that lies on the outside of the bc cell (this is called the external domain). The more bc cells there are, the more external domain is shed and it can also be a marker for cancer recurrence. However, it may not be reliable for those that do not have metastatic disease. It was mainly developed to test to see if chemo was working on reducing tumor burden instead of having to scan all the time. In Stage 1 and 2, there should not be very much if anything to measure at all. The test, in itself, is only approved for Stage 4 but many women on this board that are Stage 3B or C have been able to get it. At least one Stage 3 person on this board used the test reliably to get scanned and it showed mets. Theoretically, one could use it this way but there is no protocol.

It is common, during chemo, that the tumor marker goes up then down again. Do not be concerned with this, especially at your stage.

Hug to you

09-27-2007, 07:30 PM	#2
Becky Senior Member Join Date: Sep 2005 Location: Stockton, NJ Posts: 4,179	The CA 27/29 measures a protein that cells make but cancerous tumors make more of. This is why everyone (to include those who never had cancer) would get some type of positive number. The Her2 Serum test tests for the cleaved external part of the Her2 receptor that lies on the outside of the bc cell (this is called the external domain). The more bc cells there are, the more external domain is shed and it can also be a marker for cancer recurrence. However, it may not be reliable for those that do not have metastatic disease. It was mainly developed to test to see if chemo was working on reducing tumor burden instead of having to scan all the time. In Stage 1 and 2, there should not be very much if anything to measure at all. The test, in itself, is only approved for Stage 4 but many women on this board that are Stage 3B or C have been able to get it. At least one Stage 3 person on this board used the test reliably to get scanned and it showed mets. Theoretically, one could use it this way but there is no protocol. It is common, during chemo, that the tumor marker goes up then down again. Do not be concerned with this, especially at your stage. Hug to you __________________ Kind regards Becky Found lump via BSE Diagnosed 8/04 at age 45 1.9cm tumor, ER+PR-, Her2 3+(rt side) 2 micromets to sentinel node Stage 2A left 3mm DCIS - low grade ER+PR+Her2 neg lumpectomies 9/7/04 4DD AC followed by 4 DD taxol Used Leukine instead of Neulasta 35 rads on right side only 4/05 started Tamoxifen Started Herceptin 4 months after last Taxol due to trial results and 2005 ASCO meeting & recommendations Oophorectomy 8/05 Started Arimidex 9/05 Finished Herceptin (16 months) 9/06 Arimidex Only Prolia every 6 months for osteopenia NED 18 years! Said Christopher Robin to Pooh: "You must remember this: You're braver than you believe and stronger than you seem and smarter than you think"