PET/MR effective for imaging recurrent prostate cancer

June 11, 2013

When prostate cancer makes a comeback, it becomes increasingly important to have exceptional imaging available to find all possible regions where cancer has spread to other parts of the body, or metastasized, in order to plan the best possible treatment. A relatively new imaging system that simultaneously combines positron emission tomography and magnetic resonance (PET/MR) demonstrates a higher capacity for mapping recurrent prostate cancer than the already high standard of integrated PET and computed tomography (PET/CT), say researchers presenting a study at the Society of Nuclear Medicine and Molecular Imaging's 2013 Annual Meeting.

PET/MR provides superb soft tissue contrast with its MR component, compared to PET/CT, which focuses more on structure and density imaging with CT. This study ushers PET/MR into the ring of clinical practice by exhibiting clear benefits for with metastatic tumors.

In this comparative study recurrent prostate cancer is imaged both with PET/MR and PET/CT with the agent C-11 choline, which was approved for this use by the U.S. (FDA) last year. Choline is a naturally occurring B vitamin complex that is avidly bound by upon injection, even those that have traveled through the bloodstream and taken up residence to develop elsewhere, which is especially likely in the lymph nodes and in bone.

"The combination of PET, here with C-11 choline, and functional MRI provides complementary information that increases diagnostic certainty with higher detection rates, especially for more precise localization of recurrence. This could help to better tailor specific therapy, e.g., radiation of the pelvis versus antihormonal therapy, for patients with metastatic prostate cancer," said Matthias Eiber, MD, lead scientist for the study from TU Muenchen in Munich, Germany.

Methodology included a study population of 31 patients who had both PET/CT and PET/MR performed for restaging of recurrent prostate cancer with single injection of the imaging agent C-11 choline. PET/CT scans occurred about five minutes after injection, and PET/MR scans occurred about 51 minutes after injection. Scans were interpreted separately and all detected lesions were categorized according to suspected metastases as definitely, probably or indeterminately metastatic. Researchers discovered that PET/MR found more areas of metastases—17 in 12 different patients—when compared to PET/CT, which found 12 areas of metastases in eight subjects. PET/MR also found more lymph node metastases, 42 versus 39 areas of interest with PET/CT. The same held true for bone metastases, which were detected in 17 areas for five patients with PET/MR and 14 areas for four patients with PET/CT.

Simultaneous PET/MR is comparable to—if not more powerful than—PET/CT for recurrent prostate cancer. The only obvious challenge was a longer scan time than PET/CT, but it was found to be tolerable by patients undergoing PET/MR. PET/MR additionally offers considerably lower radiation exposure compared to PET/CT. As many of these patients often get a series of examinations in the course of their disease, despite their high average age, radiation protection could be another argument for the promotion of PET/MR. This molecular imaging technique can now be considered a conceivable alternative to PET/CT for restaging prostate metastases, especially when small local tumor recurrences are involved.

"In principle, whole-body integrated PET/MR is a technique that is officially commercially available; however, so far only a limited number of these scanners have been installed worldwide," said Eiber. "Showing a concrete example of how combining PET and functional MR imaging benefits patients with metastatic prostate cancer could potentially motivate continued PET/MR research in this field."

Explore further: Heart: Cardiac PET/MR measures up to PET/CT

Related Stories

Heart: Cardiac PET/MR measures up to PET/CT

June 10, 2013
Just a few years ago, integrated positron emission tomography and magnetic resonance (PET/MR) imaging was found only in research institutes, but little by little the technology has expanded into clinical practice. This is ...

Breast cancer: PET and MR predict chemotherapy's ability to prolong life

June 11, 2013
For patients with advanced breast cancer, positron emission tomography (PET) and magnetic resonance (MR) imaging can improve quality of life and survival by providing physicians with information on the effectiveness of chemotherapy ...

PET/CT shows clear advantages over conventional staging for breast cancer patients

January 2, 2013
New research published in the January issue of The Journal of Nuclear Medicine shows that 18F-fludeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) imaging offers significant prognostic stratification ...

Trio of studies support use of PET/CT scans as prostate cancer staging tool

October 21, 2011
Recent studies have suggested that C-11 choline positron emission tomography/computerized tomography (PET/CT) scans can be utilized as a staging and potentially therapeutic tool in prostate cancer. The results of three studies, ...

Mayo Clinic gets FDA approval for new imaging agent for recurrent prostate cancer

November 8, 2012
Mayo Clinic has received U.S. Food and Drug Administration approval to produce and administer Choline C 11 Injection, an imaging agent used during a positron emission tomography (PET) scan to help detect sites of recurrent ...

Demographic variation in early PET scan use for NSCLC

June 10, 2013
(HealthDay)—For Medicare beneficiaries with non-small-cell lung cancer (NSCLC), demographic differences in the rates of positron emission tomography (PET) scan use persisted from 1998 to 2007, according to research published ...

Recommended for you

Clear link between heavy vitamin B intake and lung cancer

August 22, 2017
New research suggests long-term, high-dose supplementation with vitamins B6 and B12—long touted by the vitamin industry for increasing energy and improving metabolism—is associated with a two- to four-fold increased lung ...

Study provides insight into link between two rare tumor syndromes

August 22, 2017
UCLA researchers have discovered that timing is everything when it comes to preventing a specific gene mutation in mice from developing rare and fast-growing cancerous tumors, which also affects young children. This mutation ...

Retaining one normal BRCA gene in breast, ovarian cancers influences patient survival

August 22, 2017
Determining which cancer patients are likely to be resistant to initial treatment is a major research effort of oncologists and laboratory scientists. Now, ascertaining who might fall into that category may become a little ...

Study identifies miR122 target sites in liver cancer and links a gene to patient survival

August 22, 2017
A new study of a molecule that regulates liver-cell metabolism and suppresses liver-cancer development shows that the molecule interacts with thousands of genes in liver cells, and that when levels of the molecule go down, ...

Zebrafish larvae could be used as 'avatars' to optimize personalized treatment of cancer

August 21, 2017
Portuguese scientists have for the first time shown that the larvae of a tiny fish could one day become the preferred model for predicting, in advance, the response of human malignant tumors to the various therapeutic drugs ...

Scientists discover vitamin C regulates stem cell function, curbs leukemia development

August 21, 2017
Not much is known about stem cell metabolism, but a new study from the Children's Medical Center Research Institute at UT Southwestern (CRI) has found that stem cells take up unusually high levels of vitamin C, which then ...

0 comments

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.