What are the non-surgical options for prostate cancer?

The established non-surgical options for localised prostate cancer are active surveillance and radiotherapy.

Treatment decisions for localised prostate cancer depend on the risk category – low, intermediate or high. This in turn is determined by the extent of the tumour, Gleason grade and PSA blood test number. 

The Gleason grade refers to how aggressive the cancer cells look under the microscope.

Active surveillance is suitable for low-risk men with small, low Gleason grade tumours in the prostate. Immediate treatment is deferred, and the cancer is monitored carefully using the PSA blood test and examination of the prostate. A repeat biopsy of the prostate is also recommended to confirm the cancer remains non-aggressive. Treatment with surgery or radiation therapy is only initiated when the tests suggest the cancer is at risk of growing, or if the man chooses to end surveillance. 

Radiation therapy uses high energy radiation directed at the cancer to eliminate it. It is painless. The two main types are intensity modulated radiotherapy (IMRT) and brachytherapy. 

IMRT is delivered from an external source using a machine called a linear accelerator, which directs high energy x-rays to the prostate according to a computer plan designed by the radiation oncologist. It used to be given slowly over 37 or more daily sessions over around 2 months. Recent trials show it is safe to deliver it over 20 sessions in 4 weeks.

Brachytherapy is the use of radioactive sources implanted within the prostate via needles. The implant may be permanent in the form of around 100 radioactive seeds that release short range radiation slowly over months (Low Dose Rate Brachytherapy). Temporary implants involve passing radioactive pellets via plastic tubes into the prostate for a few minutes before withdrawing them (High Dose Rate Brachytherapy). It is done in a few sessions over a period of 1-2 days. 

Stereotactic body radiotherapy (SBRT) is the latest advanced external beam radiation technique that utilizes the latest technological advances in tumour targeting and radiation delivery. This short and intense treatment to the prostate involves just five outpatient treatments in less than two weeks. It has shown equivalent cure rates in low to intermediate risk prostate cancer.

Prostate cancer cells’ growth is driven by the male hormone testosterone. In intermediate and high risk cases, hormone therapy to reduce testosterone production is added to radiotherapy, to improve chances of cure. This androgen deprivation therapy comes in the form of a quarterly injection into the tummy fat. The number of injections required depends on the risk category of the cancer.

What are the cost and benefits of these options?

In well selected candidates, active surveillance does not compromise survival (<1% will die from prostate cancer) and allows men to avoid the side effects and risks of treatment for an extended period, maintaining their quality of life. That said, more than half end up going for treatment eventually. Men should be psychologically comfortable with ‘living with the cancer’ when choosing this option.

IMRT is a completely non-invasive, outpatient treatment that does not require anaesthesia. There are no surgical risks and thus it’s suitable for men who are older or have medical co-morbidities. The main cost paid is in the patient’s time – it requires multiple sessions over a few weeks. In mitigation, men can still carry out their normal daily activities and even do non-strenuous work.

Brachytherapy is somewhat in-between surgery and IMRT. Anaesthesia is required for the insertion of needles, but a prolonged hospital stay is not necessary like with surgery. Return to normal activities and work is faster than with surgery. The duration of the treatment course is substantially shorter than that of IMRT. 

SBRT seeks to combine the benefits of both IMRT and Brachytherapy in being completely non-invasive, outpatient based and yet short in duration, with minimal impact on patient lifestyle. The treatment area, which is targeted personally by the radiation oncologist for each treatment, is more focused than IMRT, so there is less collateral radiation exposure of surrounding organs.

What are the potential side effects?

Short term side effects of radiotherapy include increased frequency and urgency of both bowel and bladder movements. There are medications to reduce these, but many men do not find them troubling enough to use them. These normally settle down a month or two after radiotherapy. 

The main long term potential complications of radiotherapy include bleeding from the back passage and blood in the urine. Serious bleeding is rare with modern techniques. A new technology called SpaceOAR is now available to significantly reduce the rate of moderate and above rectal bleeding to 1%. This involves injecting a biodegradable gel into the space between the prostate and rectum, under ultrasound guidance, prior to radiotherapy. The gel increases the distance between the two organs from 0 to 1cm and thus radiation dose to the rectum is vastly reduced. Erectile dysfunction can occur up to 40% of the time, but sexual intercourse can still be possible with the help of medications like Viagra.

Hormone therapy can give rise to hot flushes, low sex drive, fatigue and weight gain.

Are non-surgical treatments suitable for patients from Stage I to Stage 4?

Stage I-III cancers can be cured successfully with radiotherapy, with the higher stages requiring addition of hormone therapy for best results.

Stage IV prostate cancer is not treated surgically as the cancer has spread outside the area of the prostate. The backbone of stage IV treatment is androgen deprivation therapy injections. There are newer oral hormone tablets that have been proven to prolong life when added to ADT. Chemotherapy is also an option when hormone therapies become less effective for the patient. PSMA Radionuclide therapy – targeted radioactive molecules that home in prostate cancer cells when injected into the blood – will be increasingly used as costs come down. 

Interestingly, giving radiotherapy to the prostate to selected low disease burden Stage IV patients has been shown in a recent UK trial to prolong life. Also, if a Stage IV patient has only a few areas (3 or less) of spread, Stereotactic Body Radiation Therapy can be employed to eliminate these tumours individually, and possibly defer needing hormone therapy.

An article by Dr Jonathan Teh

Read more: Prostate cancer early screenings can save lives

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