Kiwi men set to benefit from better prostate cancer diagnosis

Men suffering from recurrent prostate cancer will soon have better access to what's being called a generational leap forward in diagnosis.

It's new technology using a radioactive tracer to pinpoint tiny cancer cells which can otherwise be missed on conventional scans.

It's new technology using a radioactive tracer to pinpoint tiny cancer cells which are otherwise missed on conventional scans. Source: 1 NEWS

Called F-18 PSMA, or Fluorine-18 Prostate Specific Membrane Antigen, it's a radioactive tracer marker which, once injected into the patient's bloodstream, attaches itself to any prostate cancer cells in the body.

"As a clinician it's very pleasing; for the patient it's a game-changer," says Christchurch oncologist Dr Chris Wynne.

An elevated PSA blood test can indicate that a man's prostate cancer may have returned, but it doesn't tell doctors where it might be in the body.

At the moment, CT scans find larger growths but not tiny ones.

However, F-18 PSMA does.

"We can detect metastases down to two or three millimetres in size, which is a very fine level of detail," says Pacific Radiology's Dr Trevor Fitzjohn.

The fluorine tracer arrives into Pacific Radiology's Wellington and Christchurch PET scanning facilities early on Wednesday morning, following a midnight flight from Melbourne, where it is currently manufactured.

Once unpacked the race is on to get the antibody tracer injected into the patient's bloodstream while the radioactivity is still active.

The patient is then positioned on a PET scanner.

The tracer travels through his bloodstream attaching itself only to any prostate cancer cells it comes across in the body.

The PET scanner highlights these growths in red, clearly visible to even the layman's eye.

"This injected antibody looks for the antigen on the cancer cell surface and locks onto it," says Dr Fitzjohn.

Finding and pinpointing exactly where tiny growths lie gives doctors a clearer idea of how to proceed with a patient's treatment.

"We have an opportunity to remove it or give radiotherapy in many cases and potentially cure him and that opportunity’s not been there before," says Dr Wynne.

Until now only Auckland patients have had access to similar technology for prostate cancer in the city's two PET scanners.

However Pacific radiology plans to manufacture the F-18 tracer itself in Wellington from next year and is preparing to supply all five of the country's scanners.

Instead of being able to scan just three patients a site each day, Pacific Radiology hopes producing the tracer closer to home will mean less travel time and therefore greater patient access, hopefully up to around eight patients per site per day.

Pacific Radiology says it has used its tracer diagnosis on 20 patients so far in the first month of offering it in its Wellington and Christchurch PET scanner sites.

It says the cost of the PET scan/F-18 tracer diagnostic test is approximately $3000 and, although most patients so far have paid privately, the company has just scanned its first public hospital-referred patient.