Circulating Tumor Cells | Dr. Dan Rubin | Ryan Sternagel

KEY TAKEAWAYS

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What are CTCs and what do they mean?

• Cells from a collection of cancer cells, tumor or metastatic deposit
• Sometime seen on scans but not always
• Circulate in the blood or lymphatic tissues
• Can only test for the CTC in blood. Need biopsy to detect in lymphatic tissue
• The presence of CTCs doesn’t necessarily indicate metastatic cancer
• CTCs don’t live very long in the blood – persistent CTC is cause for concernCancer spreads in two ways

• Metastasize (means “evil spread”) – cells travel via blood vessels
• Direct invasion – cells invade the tissues and then access lymphatic system or blood streamWhat to look for in CTC testing

• Only available for certain cancers – ovarian, pancreatic, colon, lung, breast, prostate
• Looking for two different populations of CTCs- cytokeratin(CK)-positive and CK-negative
  • ➔  CK is an anchor molecule for cells
  • ➔  CK-negative cells are cells that have down regulated their CK and can leave thetissue space to ‘circulate’ as a CTC
  • ➔  CK-positive cells are rarely found in CTC tests unless through trauma or if the tumor is invasive
  • ➔  CK-negative cells can revert back to CK-positive and “anchor in” to a new tissue site
• Test results provide highly individual information about that person’s specific tumor
• Can also see some markers you’d see on pathology specimens – things that sit on the surface of cells such as androgen and estrogen receptorsHosted By:

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