Killing the cancer without harming healthy cells

Deciding on treatment for prostate cancer can seem like a minefield and many options carry huge risk of side effects which can impact on quality of life, writes Victoria Lambert

When considering what prostate cancer treatment to begin, doctors consider location of the tumour and speed of growth. Specialist nurse John Robertson of Prostate Cancer UK explains: “The two early stages of cancer are localised – contained within the prostate gland – or locally advanced having spread just outside the gland to nearby tissue.”

Most localised cancer will grow slowly, so treatment could be as simple as active surveillance, monitoring through PSA (prostate-specific antigen) testing and repeat biopsies. If doctors are concerned the cancer is aggressive or already becoming locally advanced, they will suggest hormone treatment to shrink the tumour, before surgical removal, known as a prostatectomy, carried out as open surgery or via keyhole or even robotic procedures.

Treatment controls the cancer, rather than trying to get rid of it completely. Afterwards, radiotherapy may be used to destroy remaining cancer cells, followed by hormone therapy for three years to keep cancer in remission. If cancer recurs in the prostate gland, cryotherapy – freezing and thawing to kill the cancer cells – may be used.

Side effects, principally damage to nerves during surgery or due to radiotherapy, are still an issue for patients with some left with varying degrees of impotency or incontinence as a result. “Some men will have to have the whole prostate removed,” says Marc Laniado, a Windsor-based prostate cancer specialist, who operates robotically. “But for an increasing majority, that’s not true. We treat the cancer, but preserve the tissue around it.”

Hormone therapy

Hormone treatment helps control prostate cancer by stopping the production of testosterone or stopping testosterone reaching the prostate cancer cells where it is believed to fuel the cancer’s growth.

There are different types of hormone therapy available: GNrH agonists, such as Zoladex, stop the production of testosterone; anti-androgens block the effect. These are delivered as monthly or three-monthly injections, via an operation, tablets or implants. Hormone therapy can cause side effects, such as hot flushes, loss of sex drive and tiredness, because it reduces the levels of male hormones in the body.

Brachytherapy

Small radioactive metal seeds are placed into the tumour within the prostate gland where they release small doses of radiation very slowly over a period of time. The seeds are not removed, but stay in the prostate gland permanently.

High-dose rate (HDR) brachytherapy, also known as temporary brachytherapy, involves inserting high-dose radiation into the prostate gland for a few minutes at a time to destroy cancer cells.

It is sometimes combined with external beam radiotherapy – high-energy X-ray beams directed at the prostate gland from outside the body to damage cancer cells and stop them growing – and hormone therapy.

HIFU

High-intensity focused ultrasound is used to heat up tissue to the boiling point of water. This heat can penetrate through to localised cancer in the prostate without the need to make a surgical incision and destroy cancer cells. A rectal probe, which sends back images to a computer screen, is used so that doctor can see exactly where to treat.

Prostate cancer surgeon Marc Laniado explains: “This is a highly focused tissue-preserving therapy which attacks cancer without the side effects of treating the whole gland. No one is left incontinent and potency is preserved.”

Da Vinci robotic surgery

Useful for prostate cancer inside or just slightly outside the gland, robotic wins over conventional surgery due to the dexterity of instruments and the better vision it affords the surgeon. Usually performed as keyhole surgery, post-op pain is reduced and hospital stays are shorter.

Techniques are constantly being improved, not least by US robotic prostatectomy pioneer Dr David Samadi at New York’s Mount Sinai Medical Center. Mr Laniado concludes: “Side effects such as nerve damage seem to be reduced, but success still comes down to individual surgeons and how up-to-date their technique is, rather than the number of patients treated.”

Cyberknife

When treating prostate tumours with radiotherapy, the prostate moves unpredictably as air passes through the rectum and the bladder empties and fills, so radiation may be delivered imprecisely.

Cyberknife robotic radiotherapy uses smart technology to pinpoint the location of the prostate continuously, allowing radiation to target just cancer cells and reducing the risk of damaging healthy tissue.

It may be combined with external beam radiation for patients with locally advanced disease. However, Mr Laniado warns: “There is no long-term data yet and, if unsuccessful, it is then more difficult for the prostate to be removed without damaging nerves.”