New research may point to better predictor of prostate cancer survival

March 21, 2014 by Leslie Ridgeway

New research by USC Norris Comprehensive Cancer Center scientists demonstrates that measuring circulating tumor cells (CTCs) – the cells that spread cancer through the body – may be a better predictor of patient survival than the prostate specific antigen (PSA).

The research was published March 10, 2014 in the Journal of Clinical Oncology by a team led by Amir Goldkorn, M.D., assistant professor of medicine at USC Norris, part of Keck Medicine of USC. Goldkorn's team discovered that elevated CTC counts after chemotherapy indicated as much as a five-fold higher risk of death, and for patients whose CTCs dropped by 50 percent or more, the risk of death was cut in half. The study demonstrates CTCs are an important biomarker for and treatment.

"The significance of these findings is that looking at CTCs before and three weeks after the first cycle of chemotherapy is an early indicator of whether these men would do well with treatment and how long they may live," Goldkorn said. "This could help guide clinicians' treatment decisions and save patients from toxic treatment that won't help them."

According to the American Cancer Society, is the second most common cancer in American men. The society estimates that for 2014, about 233,000 new cases of prostate cancer will be diagnosed and about 29,480 men will die of prostate cancer.

Using blood samples from prostate cancer patients enrolled in phase 3 clinical trial, Goldkorn's team studied baseline counts of CTCs in blood samples before chemotherapy in 263 men. They then measured CTCs three weeks after chemotherapy and determined "hazard ratios" – the likelihood of a patient surviving after chemotherapy.

CTCs are a growing area of interest to many cancer researchers because these cancer cells are shed from tumors into the blood, spreading the cancer throughout the body. The theory behind Goldkorn's research was that isolating and analyzing CTCs could provide a powerful tool giving a snapshot of a patient's at a certain place and time with no need for invasive biopsies.

CTCs are rare – 100 in a typical blood sample, compared to billions of and millions of . To streamline the isolation process, Goldkorn established a CTC core lab at USC Norris and worked with Yu-Chong Tai of CalTech to create microfilter technology to enrich CTCs in .

The research sprang from a 2008 phase 3 clinical trial conducted as part of the SouthWest Oncology Group (SWOG), of which USC Norris is a member. Although the drug tested in the trial did not show a positive outcome, the method used – drawing blood before and after treatment starts and counting CTCs – indicated that the number of CTCs could act as a biomarker to determine a patient's clinical course and help select the most appropriate therapy, Goldkorn said.

Goldkorn's team plans to follow up this study with more research analyzing whether choosing therapy based on changes in CTC counts can improve disease outcomes. At the same time, the researchers are molecularly analyzing CTCs to discover what genes they express and what mutations they possess to inform clinicians' courses of treatment.

Explore further: Changing chemo not beneficial for metastatic B.C. patients with elevated circulating tumor cells

More information: "Circulating Tumor Cell Counts Are Prognostic of Overall Survival in SWOG S0421: A Phase III Trial of Docetaxel With or Without Atrasentan for Metastatic Castration-Resistant Prostate Cancer," … rch-type=QuickSearch

Related Stories

Changing chemo not beneficial for metastatic B.C. patients with elevated circulating tumor cells

December 13, 2013
For women with metastatic breast cancer who had elevated amounts of circulating tumor cells (CTCs) in their blood after a first line of chemotherapy, switching immediately to a different chemotherapy did not improve overall ...

Capturing live tumor cells in the blood

August 8, 2013
Tumor cells circulating within a patient's bloodstream can carry cancer from a primary tumor site to distant sites of the body, spreading the disease.

Detecting circulating tumor cells

March 25, 2013
A proof-of-concept device is nearly perfect in separating breast cancer cells from blood.

Circulating tumor cells in blood can predict a patient's response to chemotherapy

December 3, 2013
Scientists from Granada have demonstrated, for the first time, that detecting circulating tumour cells (CTCs) in blood and studying the presence of certain genetic markers in them is a technique that allows specialists to ...

Blood test could lead to improved diagnosis and treatment of breast cancer

June 5, 2012
Scientists have discovered that a simple blood test could lead to better diagnosis and treatment for early-stage breast cancer patients, according to an Article published Online First in The Lancet Oncology.

Cancer cells in blood predict chances of survival and can help target breast cancer treatment

March 22, 2012
Detecting the presence of circulating tumour cells (CTCs) in the blood of women with early breast cancer after surgery but before the start of chemotherapy can provide useful information about their chances of surviving the ...

Recommended for you

New therapeutic approach for difficult-to-treat subtype of ovarian cancer identified

July 24, 2017
A potential new therapeutic strategy for a difficult-to-treat form of ovarian cancer has been discovered by Wistar scientists. The findings were published online in Nature Cell Biology.

Anti-cancer chemotherapeutic agent inhibits glioblastoma growth and radiation resistance

July 24, 2017
Glioblastoma is a primary brain tumor with dismal survival rates, even after treatment with surgery, chemotherapy and radiation. A small subpopulation of tumor cells—glioma stem cells—is responsible for glioblastoma's ...

Immune cells the missing ingredient in new bladder cancer treatment

July 24, 2017
New research offers a possible explanation for why a new type of cancer treatment hasn't been working as expected against bladder cancer.

No dye: Cancer patients' gray hair darkened on immune drugs

July 21, 2017
Cancer patients' gray hair unexpectedly turned youthfully dark while taking novel drugs, and it has doctors scratching their heads.

Shooting the achilles heel of nervous system cancers

July 20, 2017
Virtually all cancer treatments used today also damage normal cells, causing the toxic side effects associated with cancer treatment. A cooperative research team led by researchers at Dartmouth's Norris Cotton Cancer Center ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.