- Among women with the earliest stage of invasive breast cancer (stage 1), 25% of them already have breast cancer cells that can be found in their bone marrow. (reference)
- Among men with the earliest stages of prostate cancer (pT2, no lymph node involvement, Gleason scores </=6, PSA </=4 ng/mL), over 70% of them have prostate cancer cells that can be found in their bone marrow. Even among the men who are presumed cured after prostatectomy (3 months postoperative PSA <0.4 ng/mL), 57% of them have prostate cancer cells within their bone marrow. (reference)
These and many other studies confirm that the silent (occult) presence of these metastatic cells, whether they are in the bone marrow (called, “disseminated tumor cells” or “DTC’s”) or circulating within the blood(called, “circulating tumor cells” or “CTC’s”), is not surprisingly associated with a higher rate of recurrence and death from their cancer in the future.
CTC’s are able to be detected by taking a sample of the patients blood and submitting it for analysis. DTC’s are detected by analyzing a sample of tissue taken from a bone marrow biopsy (a more painful procedure than a blood draw, and thus less desirable.)
Studies have clearly shown that not all patients with measurable CTC’s or DTC’s will go on to develop a detectable metastatic tumor. These cells may be attacked and killed by the body’s immune system, they may self-destruct (apoptosis) or they may remain dominant within the body. However, if the conditions are right they will grow into a metastatic tumor. These conditions can include:
- suppressed immune system
- excessive free radicals (oxidation)
- stimulation by tumor growth factors/hormones
Researchers are currently studying the clinical use of tailoring cancer treatment (i.e. chemotherapy, immune therapy, etc.) based on the response as measured by following the number of CTC’s or DTC’s. This is an exciting area of research, as typically oncologists will give a cancer-killing drug for 1-3 months before assessing the response to treatment using radiographic scans (i.e. PET/CT, CT, MRI, etc.). The use of CTC or DTC analysis enables the oncologist to assess response to treatment after each dose of drug, facilitating a more rapid change to an alternative drug that may be more effective. Use of CTC’s and DTC’s to tailor cancer treatment may be one of the most important advances in the field of oncology.
Now that I have discussed the significance of these silent (occult), metastatic cancer cells, I hope that everyone reading this blog will recognize that by implementing an anticancer lifestyle you may be able to influence the biological terrain that can help keep these cells in check (dormancy or cell death.)
The future of integrative oncology research will need to include the assessment of response to specific anticancer lifestyle interventions on CTC’s or DTC’s. In the meantime (while we await years for this data to be available), there is already a substantial body of evidence to support that these healthy interventions will improve cancer outcomes…so don’t delay, and get on the anticancer bandwagon now.
Learn more about CTC’s:
What is the clinical relevance and biology of CTC’s? (Breast Cancer Research: review article)
The latest technology in capturing and analyzing CTC’s