Scan that makes prostate cancer cells glow could cut need for biopsies

Findings from the PRIMARY2 trial are presented today [Friday 13 March 2026] at the European Association of Urology Congress in London (EAU26). 

The PSMA PET/CT scan identifies more aggressive prostate cancer cells, which are potentially harmful and may need treatment. It does this with a molecule that binds to prostate cancer cells and causes them to ‘glow’, appearing as bright spots in the scanning image. This could also help reduce the risk of overdiagnosis by determining which cancer_Butes are low-risk and will never cause harm, the study says. 

People with suspected prostate cancer usually have an MRI scan to look for abnormal areas of the prostate. If MRI results are suspicious or inconclusive, patients undergo a biopsy that takes small pieces of prostate tissue and looks for cancer cells. This is a routine but invasive procedure that can be uncomfortable and sometimes worrying for patients and is associated with side effects. 

The PRIMARY2 trial recruited people at higher risk of prostate cancer, such as a strong family history, who had a normal result on their MRI. These people often go ahead with prostate biopsy. They were randomly assigned to have either a standard biopsy or a PSMA PET/CT scan. 

PSMA PET/CT scanning could identify people who either did not have cancer, or whose cancer was so low-risk or slow-growing it would likely never cause harm. These people did not need a biopsy. Meanwhile, people with a positive PSMA PET/CT scan result had a biopsy. This approach halved the number of people who needed a biopsy, without missing any harmful cancers. 

For patients who still needed a biopsy, their scan results ensured the procedure was targeted to the suspicious areas identified in the test to minimise complications and improve accuracy. 

These are the first results released from PRIMARY2, which will follow these 660 patients for two years. PRIMARY2 is an Australia-wide phase III clinical trial, led from Peter MacCallum Cancer Center in Melbourne and St Vincent’s Hospital in Sydney. PSMA PET/CT scanning is becoming increasingly accessible in the UK and Europe, primarily for diagnosing high-risk or recurrent prostate cancer, although cost and availability remain limitations to widespread use. It is widely available in Australia. 

Dr James Buteau, a nuclear medicine physician at Peter MacCallum Cancer Centre, is presenting the research at EAU26. He said: “PSMA PET/CT scanning makes prostate cancer cells light up in a remarkable way, particularly in more aggressive cancers. It’s rare to see such strong imaging that could be so powerful in the clinic. Incorporating this testing into clinical care could help to address the major challenge of prostate cancer overdiagnosis, which leads to at best unnecessary and at worst harmful treatment for cancers that would never cause any harm.”

Professor Louise Emmett, Director of Theranostics and Nuclear Medicine at St Vincent's Hospital co-led the study with Professor Michael Hofman from Peter MacCallum Cancer Centre. She said: “Getting told you have a risk of prostate cancer is a huge cause of anxiety and concern. Our findings show that PSMA PET/CT after MRI offers a 'belt and braces' approach that can determine which people have a clinically significant cancer, and which people are at low risk and don’t need a biopsy or further testing. PRIMARY2 is the largest of a series of studies undertaken by this group, exploring whether PSMA PET/CT scanning could improve prostate cancer diagnosis and reduce unnecessary biopsies for patients.”

Prof Dr Derya Tilki is a member of the EAU Scientific Congress Office and a senior consultant urologist at Martini-Klinik Prostate Cancer Center, Germany. She said: “This well-conducted trial shows that incorporating PSMA PET/CT in men with low or intermediate risk lesions – defined by MRI as PI-RADS 2 or 3 – significantly reduced the number of unnecessary biopsies and the diagnosis of clinically insignificant prostate cancer. Importantly, this didn’t compromise the detection of clinically significant disease. These results support consideration of PSMA PET/CT in the diagnostic work-up of appropriately selected patients. I congratulate the investigators on their study.”

ENDS

For further information, contact:

Abi Chard/ Dan Richards-Doran
Campus PR & Communications
+44 (0) 7960 448 532 / +44 (0) 7957 351 810
eaupress@campuspr.co.uk 

Embargoed to: Friday 13 March 2026 00:01 UK time 
Not peer-reviewed | Multicentre Randomised Phase III Trial | In people 

Notes to editors 

Patients were recruited to PRIMARY2 after receiving a PI-RADS score of 2 or 3 from MRI, combined with other prostate cancer risk factors such as rising PSA score or strong family history. 

Participants in the control arm underwent transperineal prostate biopsies while those in the experimental arm underwent pelvic PSMA PET/CT scanning. In the control arm, 44% of people had a biopsy when they did not have prostate cancer, compared to 22% in the experimental arm. In the control arm, 32% of people had a low-risk or slow-growing cancer that needed no treatment, compared to 14% in the experimental arm. 

Impact of [68Ga]Ga-PSMA-11 PET/CT in the diagnosis of prostate cancer in men with equivocal or non-suspicious findings on multiparametric MRI (PRIMARY2): a multi-centre, phase III, randomised trial by Buteau J.P., Moon D., Fahey M.T., Roberts M.J., Ayati N., Papa N., Murphy D., Kasivisvanathan V., Du Y.T., Hutton A.C., Jack G., Lee S.F., Lee S.T., Leslie S., Levy S.M., Mitchell C., Morigi J.J., Nguyen A., Patel M.I., Pattison D.A., Yaxley J., Thompson J., Hofman M.S., Emmett L. is presented at EAU26 on Friday 13 March 2026. 

About EAU26

The 41st Annual Congress of the European Association of Urology (EAU26), Europe’s biggest urology conference, takes place from 13-16 March 2026 in London, UK. Around 2,000 abstracts will be presented and moderated live, covering subjects ranging from prostate, kidney and bladder cancer to urinary incontinence and erective dysfunction. The packed four-day scientific programme includes live surgery, state-of-the-art lectures, case discussions and debates. See the full scientific programme on the congress website: https://eaucongress.uroweb.org/

About PRIMARY2

PRIMARY2 is sponsored by the Peter MacCallum Cancer Centre, co-led with St Vincent’s Hospital, Sydney. The study is funded by the U.S. Prostate Cancer Foundation (PCF), supporting both the Prostate Cancer Theranostics Imaging Centre of Excellence (ProsTIC) and Louise Emmett, St Vincent’s Hospital Curran Foundation, Peter MacCallum Cancer Foundation, National Health and Medical Research Council (NHRMC) and the Australian and New Zealand Urogenital and Prostate (ANZUP) Cancer Trials Group.

About Peter MacCallum Cancer Center 

Peter MacCallum Cancer Centre is a world leading cancer research, education and treatment centre and Australia’s only public health service dedicated to caring for people affected by cancer.

About St Vincent’s Hospital Sydney 

St Vincent’s is a unique not-for-profit social enterprise that features two major inner-city health networks in Melbourne and Sydney, 10 private hospitals, 26 aged care facilities – with more than 3,000 hospital beds and 2,500 residential aged care beds – and a range of virtual and home care options.