Bajan men in cancer research to reduce deaths

With prostate cancer ranking as the most common cancer and accounting for the highest number of cancer deaths here, the Barbados Cancer Society (BCS) is using samples from Barbadian men in international research with the ultimate aim of reducing the number of people dying from the disease.

Reporting on the BCS Prostate Cancer Trial 2020-2021, on Friday, World Cancer Day, Acting President of the Society Professor David Rosin said it was hoped that the discovery of a molecular signature would become readily available – like DNA testing to discover a man’s heritage – at a reasonable price in the near future.

He said this liquid biopsy, as it is also called, will allow for cancers of the prostate to be prediagnosed and followed up with parametric MRI scans and treated as early as possible, hopefully resulting in reduced deaths.

More than 300 men are diagnosed with prostate cancer annually in Barbados. The latest figures from 2018 show 113 men died from the disease.

Professor Rosin said work has been done in the United Kingdom by Professor Mark Emberton and his team at the Institute of Urology, University Hospital, London, on the new parametric MRI scans.

He said findings have shown the scans to be successful for diagnosing prostate cancer, leading to the number of biopsies falling to 50 per cent with vertically no false positive or negative results, since biopsies under MRI control are almost 100 per cent accurate.

“In partnership with Yale University & Wren Laboratories, Massachusetts, USA, the Barbados Cancer Society ran a trial comparing the standard screening blood test, the Prostatic Specific Antigen (PSA), with a newly discovered DNA molecular signature specific for prostate cancer which can be detected in a drop of blood.

“We recruited over 500 volunteers who were mainly men of African descent. Being a country in which the population is predominantly (92.4 per cent) who are of African descent, this is the largest and first trial carried out in black men. Also, with a fairly static population, these volunteers are easy to follow up,” Professor Rosin said.

A total of 554 men entered the trial, 114 of them being over the age of 50 – because prostate cancer is present in younger men in Barbados – and 40 others between ages 40 and 50 recruited as controls.

Professor Rosin said although analysis is still ongoing, it was found that 80 of the men tested had a positive molecular signature. Of these, 20 were known to have had prostatic cancer in the past and were being treated.

“Most importantly, the other 60 participants in the trial with positive molecular signature had no symptoms or signs and with normal PSA levels. We have counselled these 60 men and are following them regularly. Most have had repeat molecular signature estimations as well as repeat PSA tests. We intend to discover their prostatic cancer when in a very early stage so that the treatment will be less radical and more effective,” Professor Rosin said.

“Molecular signatures in the blood have been found for a number of cancers, including prostate, colon, breast, lung, and endocrine, and each specific for that cancer. They have been found to have a sensitivity of 94 and a 100 per cent specificity,” he added.

“Most importantly, it will be positive before there are symptoms, signs, or positive imaging.

It has been shown to be present three years before cancer is clinically present. Another bonus is that it can predict the aggressiveness of the cancer and is useful to follow up patients after treatment to find the response.” anestahenry@barbadostoday.bb