PROSTATE CANCER & ROBOTICS

1. Diagnosis

PSA
Prostate cancer is the most common cancer in men and the 2nd leading cause of cancer death. The main risk factor is family history of the disease. Men with a first-degree relative with prostate cancer have almost three times the risk of developing prostate cancer. This increases to 10 times with two relatives with the condition.

Diet may have a role in developing prostate cancer and populations of men with the most risk factors for heart disease also have the highest incidence of Prostate Cancer. The best prevention is to maintain ideal body weight, regular exercise and balanced diet, control of blood pressure, diabetes and cholesterol and no smoking.

Prostate cancer is screened with PSA – Prostate Specific Antigen. This peptide is produced by the healthy prostate and in higher levels with Prostate Cancer, prostate infection, large prostates and other inconsistent factors. The Urological Society of Australia and New Zealand recommends regular testing from age 45 years in all men and from 40 years in those with a strong family history.

PSA levels vary according to age reflecting growth of the prostate with increasing years. PSA can also be interpreted by the rate of rise over time – known as PSA velocity – and by the Free:Total ratio. The PSA should be repeated several weeks after the first reading to ensure it is genuinely elevated. Any urine infection or prostatitis should be treated and the PSA repeated.

Occasionally the PSA may be normal but the prostate feels irregular or nodular on examination. This requires further investigation because it is possible to have prostate cancer with normal PSA levels.

Prostate MRI
Prostate MRI has become an excellent adjunct to the diagnosis of Prostate Cancer and in assisting decision-making when cancer is identified. MRI tends to be less sensitive at detecting slower growing prostate cancers but is excellent for detecting faster growing tumours. The scans can be used to decide when biopsies are required immediately or can be delayed, where to guide the biopsies, and the possibility of a prostate cancer beginning to grow outward through the capsule of the Prostate.

Remember: a negative MRI scan does not rule out Prostate Cancer. And a lesion seen on MRI is not always cancer but provides increased risk of the disease.

Prostate biopsy – Transperineal biopsies
The absolute diagnosis of Prostate Cancer is made by tissue samples. Occasionally this can occur with TURP (the operation to remove the inner zone of the prostate to relieve blockage), but mostly the diagnosis is made with needle biopsies of the prostate taken under ultrasound guidance usually under anaesthetic. The Transperineal technique is very precise and rarely associated with infection that was a major potential issue when the biopsies were taken through the wall of the rectum. It still uses an ultrasound probe into the rectum to show highly details anatomical images of the Prostate.

If the MRI scan shows a lesion, the images can be superimposed on the ultrasound image of the Prostate to provide precision in the biopsies (MRI fusion technique). Otherwise tissue cores are taken from six separate zones of the prostate.

The biopsies reveal the presence of cancer, how extensive it is through the Prostate and how aggressive the cancer cells are. This information is very important to decide the best course of management. TP biopsies are the technique I use exclusively for Prostate biopsies due to the precision and the safety factors.

2. Active Surveillance

Active surveillance is perhaps the greatest advance in Prostate Cancer management in the last 20 years. Not all Prostate Cancer is aggressive and many can be observed closely with PSA testing and occasional repeat imaging and biopsies. The goal is to select the slow and moderate growth patterns which are not extensive at diagnosis.

I use the Active Surveillance criteria developed through the Monash Urology Prostate Cancer Protocols and cancer Pathway. The cancers should be in no more than 2 of 6 zones in the Prostate and should have a Gleason grade 3 or less (or score of 6). The Gleason score is a system of describing the aggressiveness of the cancer with an area of 2 or 3 being slow and moderate growth, and areas of 4 and 5 being fast and very fast. The grades of two areas are added together to give the Gleason Score.

If the tumour is suitable for Active Surveillance, the PSA is measured every 3 months and after 12 – 15 months the MRI scan and biopsies are repeated. If the tumour has not grown and the PSA remains stable, follow-up consists of PSA testing alone. If the PSA starts to rise as will occur in more than 50% of cases, the cancer may be growing. Such cancers tend to grow within the prostate and are much less likely to spread to lymph nodes and bones compared to fast and very fast cancers. Thus, even with progression under active surveillance, it is possible to offer curative treatment. The advantage of Active Surveillance is to avoid surgery or radiation in those people with tumours that may never progress. This can avoid the potential complications associated with treatment.

3. Robotic Prostatectomy

Robotic surgery is advanced laparoscopic surgery with imaging and ergonomic advantages over conventional laparoscopic equipment. The technology involves the primary surgeon controlling the camera position and magnification, as well as three additional working arms to control surgical instruments, with a clutch mechanism to interchange the 3rd and 4th arms. The surgeon sits at a separate console and an assistant is at the operating table using two additional access ports for suction and delivery of surgical equipment such as sutures and retrieval bags.

The vision at the console is a magnified 3-D image and the instruments are “wristed” to allow a wider range of movement to enhance dissection / access / suturing. This allows precise anatomical definition of tissue planes and significantly improved access for more complex surgery compared to standard laparoscopy. The device has Tremor Filtration Technology and Motion Scaling to improve precision and eliminate the effect of human tremor on fine dissection. There are significant ergonomic advantages for surgeons assisting fatigue, consistency and sustainability.

Robotic Prostatectomy vs Open Radical Prostatectomy
– There is equivalent outcomes of cancer margins rates with Robotic Surgery, continence and Erectile Function. The primary determinate of these outcomes is the experience and skill of the surgeon
– Superiority for robotic surgery in terms of less post-operative pain, decreased transfusion rates, shorter length of stay, quicker return to work and higher patient satisfaction
– Significant decrease in reported rates of Bladder Neck Contracture in Robotic Prostatectomy compared to the open procedure
– Duration of post-operative catherization varies for surgeon to surgeon but in my practice, we generally remove catheters after just 10 days with robotic Prostatectomy

Since commencing robotic training in 2016 and attending the iconic Robotic Training Centre in Tokyo I now prefer Robotic Prostatectomy even though I have performed more than 1000 open Radical Prostatectomy operations. It is very rewarding to see the majority of patients recover so quickly from major surgery and able to return home in 1-2 days.

I now use a nerve sparing technique that comes from beneath the prostate near the apex of the gland and safely pushes the nerve away at this point where it starts to separate from the prostate. The nerve packet can then be dissected off the prostate with atraumatic techniques possible with Robotic vision and motion. This technique appears to provide the best possible outcomes for erectile function after the surgery. It is not always possible to spare the nerve especially when the cancer is large, close to the nerve and fast growing. Consideration of all factors is given in every case.

In terms of Urinary Continence after Robotic Prostatectomy, the key aspect is the functional length of the urinary sphincter that can be maintained. The Prostate itself has sphincter function so inevitably some function is lost. The urethra can be dissected from the apex of the prostate using atraumatic technique to preserve the functional urethral length maximally. It is sutured to the bladder when the prostate has been removed under magnified direct vision to provide ideal approximation.

In my hands there has been no deterioration in the excellent cancer margins using Robotic techniques compared to open. The robotic arms and vision allows excellent separation of tissues revealing the optimum points of dissection to maintain function and at the same time remove the entire cancer.