HER2 Support Group Forums - View Single Post - circulating tumor cells as risk factor --in patients with early bc (stage 1-3)

Becky · 09-25-2007, 10:04 AM

They are not the same.

A circulating tumor cell (CTC) is exactly what you think - a breast cancer cell in the bloodstream.

Tumor marker (let's say CA 27/29) measure the amount of a certain protein. Tumors produce more of this protein that normal cells (and/or organs). So, when tumors are growing and getting bigger (or spreading), more of the protein is being produced and the "tumor marker" goes up and can be measured in the blood. (This is kind of like being pregnant. You don't do an ultrasound to try to find a tiny object but you can measure the amount of pregnancy protein (in this case, HCG) in urine).

09-25-2007, 10:04 AM	#5
Becky Senior Member Join Date: Sep 2005 Location: Stockton, NJ Posts: 4,179	They are not the same. A circulating tumor cell (CTC) is exactly what you think - a breast cancer cell in the bloodstream. Tumor marker (let's say CA 27/29) measure the amount of a certain protein. Tumors produce more of this protein that normal cells (and/or organs). So, when tumors are growing and getting bigger (or spreading), more of the protein is being produced and the "tumor marker" goes up and can be measured in the blood. (This is kind of like being pregnant. You don't do an ultrasound to try to find a tiny object but you can measure the amount of pregnancy protein (in this case, HCG) in urine). __________________ 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"