Oxygen in tumors predicts prostate cancer recurrence

Low oxygen levels in tumors can be used to predict cancer recurrence in men with intermediate-risk prostate cancer even before they receive radiation therapy.

The , led by radiation oncologists at the Princess Margaret Hospital (PMH) Cancer Program, University Health Network (UHN) is published online today in , a journal of the American Association for Cancer Research (doi: 10.1158/1078-0432.CCR-11-2711).

"We've not only shown that men do worse if they have low oxygen levels (hypoxia) in their , but that they also do worse over a shorter period of time," says Dr. Michael Milosevic, radiation oncologist in the PMH Cancer Program, UHN. "These patients seem to develop within only a few years of completing treatment."

"This information could change the way prostate cancer is treated and goes a long way to ensuring that all patients receive the right treatment from the outset – based on their individual tumour," says Dr. Milosevic, who is also a professor of radiation oncology at the University of Toronto. "At the heart of it, this is what personalized medicine is all about."

Prostate cancer is commonly treated with surgery or , and yet cancer recurs or spreads in about 25% of treated men. The discovery of indicators, such as low oxygen in tumours, enables doctors to better select the most appropriate and effective treatments for each patient even before radiation therapy is delivered.

Dr. Milosevic and colleagues measured in 247 men with localized prostate cancer prior to radiation therapy and followed them for a median of 6.6 years. Low oxygen in the tumors predicted early relapse after radiation treatment. It was also the only identified factor that predicted local recurrence during follow-up.

"We believe that a tumour's genetic signature will be another promising predictor of recurrence," says Dr. Robert Bristow, in the PMH Cancer Program, UHN, and professor in the departments of radiation oncology and medical biophysics at the University of Toronto. "Combined, these indicators may signal that the cancer has spread at a previously-undetectable level."

Dr. Milosevic and colleagues hope that identifying the factors that influence prostate cancer behavior will lead to the exploration of new drugs to target hypoxia in tumors. The findings may also accelerate the development of new treatment strategies – informing physicians when complementary treatment may be more effective. .

"Knowing what works for which patient will make treatment more effective and improve outcomes for patients," says Dr. Milosevic.

Provided by University Health Network

5 /5 (3 votes)
add to favorites email to friend print save as pdf

Related Stories

Radiation plus hormone therapy greatly improves survival

Nov 03, 2011

Men with locally advanced or high-risk prostate cancer who receive combined radiation and hormone therapy live longer and are less likely to die from their disease, shows clinical research led by radiation oncologists at ...

Why some prostate cancer returns

May 27, 2009

The majority of men who receive one of the standard treatments for localized prostate cancer - surgery or radiation therapy - have an excellent outcome.

Recommended for you

Unraveling the 'black ribbon' around lung cancer

21 minutes ago

It's not uncommon these days to find a colored ribbon representing a disease. A pink ribbon is well known to signify breast cancer. But what color ribbon does one think of with lung cancer?

Survival hope for melanoma patients thanks to new vaccine

5 hours ago

(Medical Xpress)—University of Adelaide researchers have discovered that a new trial vaccine offers the most promising treatment to date for melanoma that has spread, with increased patient survival rates and improved ability ...

New clinical trial launched for advance lung cancer

9 hours ago

Cancer Research UK is partnering with pharmaceutical companies AstraZeneca and Pfizer to create a pioneering clinical trial for patients with advanced lung cancer – marking a new era of research into personalised medicines ...

User comments