Prostate cancer

Prostate cancer is the most common cancer in men across the developed world, affecting almost 1.5 million men worldwide each year and killing nearly 400,000 [IARC]. Numbers of new cases are set to double by 2040 [Lancet 2024].

In recent years, MRI has transformed the way that we diagnose and treat prostate cancer [European Association of Urology]. But the demand for medical imaging is growing far faster than the radiology workforce: the UK has a shortfall of over 1,900 radiologists, 30% of the workforce [Royal College of Radiologists].

Further, major studies indicate that we need to improve how we diagnose prostate cancer. For example, in the PROMIS study [Lancet, 2017], 12% of clinically significant prostate cancer (any Gleason score ≥7) was missed at MRI, and 55% of cancer-free men were indicated for potentially avoidable biopsies that lead to patient harm and use valuable clinical resources. In England, 46% of men are first diagnosed at stages III or IV – finding prostate cancer when it is difficult or impossible to cure [NPCA, 2024].

So how is a doubling in prostate cancer numbers going to be addressed along with earlier diagnosis?

Lucida Medical develops solutions like Pi to give clinicians the tools to detect cancer quickly and accurately.

Our vision is that Pi, together with MRI and other clinical data, can help detect every cancer as early and efficiently as possible while enabling those who are cancer-free to avoid costly and painful investigations and procedures.

The Prostate and Prostate Cancer

With thanks and acknowledgement to Prostate Matters and Professor Hashim Ahmed for the content of this section.

Almost all men over 60 will have one or more prostate cancer lesions, but only 3% of those will die of the disease. What is important is to find tumours that are likely to affect the patient’s life and only treat those.

Adenocarcinoma is the type of cancer that develops in gland cells. It is the most common type of cancer found in the prostate gland.

About the Prostate

The prostate is a small gland that secretes much of the liquid portion of semen, the milky fluid that transports sperm through the penis during ejaculation.

The prostate is located just beneath the bladder, where urine is stored, and in front of the rectum. It encircles, like a donut, the first section of the urethra; the tube that carries urine from the bladder out through the penis. During ejaculation, semen passes from the testicles, through the epididymis and then vas deferens. The vas on each side enters the prostate, joins an ejaculatory duct and from there enters the urethra. The bladder neck acts as a valve preventing backward passage of sperm into the bladder, and muscles around the urethra contract so that it is passed out through the penis.

The prostate is made up of three lobes encased in a thin outer covering, or capsule. It is flanked on either side by the seminal vesicles, a pair of pouch-like glands that contribute secretions to the semen. The testicles, in addition to manufacturing sperm, produce testosterone, a male sex hormone that controls prostatic growth and function.

Prostate cancer

Cancer of the prostate is a disease unique to men as only males have a prostate. As the prostate is a ‘gland’ it may develop cancer in a similar way to the glandular tissues of the breast or the thyroid.

Prostate cancer stage & grade

There are two important factors to consider when dealing with prostate cancer – the ‘stage’ and the ‘grade’.

The stage refers to how far the cancer has physically spread from its origin;

• it may still be confined to the prostate gland (‘localised or organ-confined’),
• it may have spread beyond the capsule into tissue around the prostate or organs of the pelvis (‘locally advanced’),
• it may have spread outside the pelvis (‘metastatic’) either through the blood stream or lymph glands.

The grade refers to how aggressive the cancer cells appear under the microscope and is usually given a score: more specifically, the ‘Gleason grade’, named after a histopathologist who devised a reliable system for attributing a grade.

The Gleason grade and score is made up of three numbers, such as 3+3=6, 3+4=7, 4+3=7, 4+4=8, 4+5=9 or 5+4=9. Each number refers to the two most common types of cell seen in the biopsy cancer tissue with the most common grade first. The first two numbers or ‘grades’ ranging from 1-5 are added to give the final ‘score’ ranging from 2-10. The higher the total score, the more aggressive the prostate cancer is. In the modern era, scores of 2 to 5 are rarely given as these are now commonly regarded as non-cancerous. The higher the total score, the more likely it is that the prostate cancer may spread outside the prostate. Cancers of very low grade (Gleason number) may not need treatment and can be watched (Active Surveillance) whereas cancers with higher grades are likely to require treatment. Some have advocated re-labelling Gleason 3+3=6 as a benign entity because it is low risk, although this proposition is controversial.

An enhanced type of MRI scan “multiparametric” is the recommended diagnostic test used to detect disease before biopsy . There is emerging evidence that the scan can also tell us something about the grade of a tumour.

Who is at risk?

With acknowledgement to Prostate Matters and Associate Professor Francesco Giganti.

It is important to note that the majority of men over 60 will have one or more prostate cancer lesions, but most of the time these are indolent and are not a cause for concern, in fact only 3% of those with prostate cancer will die of the disease.

What is important is to identify groups of men who are likely to be at risk of developing significant disease.

They are as follows:

• Men of West African and South African genetic heritage, that includes all men for example of Afro Caribbean decent.
• Relatives who were diagnosed with early onset prostate cancer (diagnosed before age 55)
• 3 first degree relatives (brother, son, father) diagnosed with prostate cancer
• Men with Ashkenazi Jewish ancestry with a family history breast, ovarian or prostate cancer
• A family history of Prostate cancer and two relatives with breast or ovarian cancer
• A family history of Prostate cancer and male breast cancer, or ovarian cancer or bilateral breast cancer
• A family history of Prostate cancer or early onset bowel or womb cancer (before age 50)
• A family history of Prostate cancer and/or 2 relatives with bowel or womb cancer

The size and scale of the problem

With acknowledgement to The Lancet [Lancet 2024] and The Guardian Newspaper [article]

The Lancet  Commission on prostate cancer: planning for the surge in cases

According to the Lancet Commission study published in April 2024, the number of men diagnosed with prostate cancer worldwide is projected to double to from 1.4 million in 2020 to 2.9 million a year by 2040, with annual deaths predicted to grow to almost 700,000 by 2040.

Prostate cancer is  the most common male cancer in most countries in the developed world. As populations age and life expectancy is increasing, the impact of this cancer will grow.

Many risk factors for prostate cancer – such as age and having relatives with cancer – cannot easily be avoided.

However, we now have tools to help us tackle prostate cancer more effectively and must make use of them to reduce its impact. These include new ways of testing and earlier diagnosis to find the cancer earlier so that it can be treated more effectively, and advances in therapies. This way we can reduce the burden of prostate cancer and save many lives.

“As more and more men around the world live to middle and old age, there will be an inevitable rise in the number of prostate cancer cases,” said Prof Nick James, the lead author of the study. “We know this surge in cases is coming, so we need to start planning and take action now.”

“Evidence-based interventions, such as improved early detection and education programmes, will help to save lives and prevent ill health from prostate cancer in the years to come,” added James, a professor of prostate cancer research at the Institute of Cancer Research, London, and a consultant clinical oncologist at the Royal Marsden NHS foundation trust.