Higher circulating tumor cell counts are associated with an increased risk of death.
Men with metastatic castrate resistant prostate cancer don’t have a good biomarker to predict survival. According to a study published online ahead of print in the Journal of Clinical Oncology.
by Amir Goldkorn, MD, and colleagues at the Keck School of Medicine of the University of Southern California in Los Angeles,Measuring circulating tumor cells (CTCs) may be a more effective method of predicting survival compared with PSA tests.
The researchers evaluated blood samples of 263 men with metastatic CRPC prior to their beginning chemotherapy. They enumerated CTCs at baseline and three weeks after treatment.
At the baseline the men had a median CTC count of 5 cells per 7.5 mL. The median overall survival (OS) was 26 months for men with fewer than 5 CTCs per 7.5 mL versus 13 months for those with 5 or more CTCs per 7.5 mL at baseline, which translated into a 2.7 times increased risk of death for those with 5 or more CTCs per 7.5 mL.
They also found that men who had elevated CTC counts after having chemotherapy had up to a 5-fold increased risk of death, whereas men whose CTC counts dropped by 50% or more were half as likely to die.
The authors said they believe that this method can help to prevent harmful and unnecessary testing in men who are eligible of undergoing PSA screening.
The significance of these findings is that CTC counts before and 3 weeks after the first cycle of chemotherapy are an early indicator of whether these patients would do well with treatment and how long they may live. According to Goldkorn “This could help guide clinicians’ treatment decisions and save patients from toxic treatment that won’t help them.”
What the doctor is hinting at would be electing to triage men and decide based on CTCs if we should pay for a treatment or just tell a man to pack his bags and go home to die without any additional treatments.
How do you feel about this type of medicine?
Joel T. Nowak, M.A., M.S.W.