Cancer, cure and control
Medical and technological advancements have made it possible for men with prostate cancer live long and active lives, according to Dr. Ashutosh Tewari and Dr. Abhishek Srivastava. See video | Patient's checklistUpdated: May 03, 2011 17:01 IST
Men with prostate cancer are spoilt for information and choice, yet many do not get the best treatment because they are embarrassed to talk about it and do not act early enough.
If diagnosed early enough (in the first two stages), new treatments make it possible to cure and control the cancer for you to live a long and active life. A few simple steps are all that are needed to follow to help those newly diagnosed to take charge of their lives and overcome much of the fear and anxiety that accompanies a cancer diagnosis.
The key factors in choosing the most effective treatment option includes the extent of the cancer, the patient’s age, and the presence or absence of any other significant disease.
For patients with disease confined to the prostate gland, standard treatment options include radical prostatectomy (RP), radiation therapy (external beam and/or brachytherapy), focal therapy (cryotherapy or HIFU) and active surveillance or tacking of the disease. When disease extends through the prostatic capsule into the seminal vesicles or into regional lymph nodes, definitive local therapy directed at the prostate itself may be combined with additional radiation therapy and/or systemic hormonal therapy (directed to the whole body in general).
Active surveillance The final treatment chosen depends on a number of factors: • The clinical stage of disease, tumour grade (Gleason score), and serum PSA. • Age, general medical condition, and potential life-limiting comorbidities to estimate life expectancy without treatment. • Estimated outcomes (cancer control, continence and sexual function) with different treatments. • Treatment-related side effects, including effects on health-related quality of life.
Many prostate specific antigen (PSA) screen-detected -- High blood levels of the PSA protein produced by the prostate gland is an indicator of cancer -- prostate cancers are small, harmless and thought to have a relatively low risk of progression. For many men, such disease may never require treatment or treatment can be postponed for a long time without significantly lowering the chance of cure.
The final treatment chosen depends on a number of factors:
• The clinical stage of disease, tumour grade (Gleason score), and serum PSA.
• Age, general medical condition, and potential life-limiting comorbidities to estimate life expectancy without treatment.
• Estimated outcomes (cancer control, continence and sexual function) with different treatments.
• Treatment-related side effects, including effects on health-related quality of life.
Active surveillance is the postponement of immediate treatment till there is evidence of disease progression. The goal is to avoid treatment-related complications for men whose cancers are not likely to progress while maintaining an opportunity for cure in those who show evidence of progression.
It is distinguishable from ‘watchful waiting’, which is based on the premise that the patient will not benefit from treatment of localised prostate cancer. In such cases, the decision is made at the outset to forego definitive treatment and patients are treated symptomatically as the cancer progresses. ‘Watchful waiting’ is a good alternative for elderly men and for those with other co-existing diseases.
RP is most effective when the cancer is confined to the prostate gland. It’s also an appropriate option for men with locally advanced prostate cancer or men with local recurrence after radiation therapy.
Open RP is a widely used surgical approach for treating localised prostate cancer, with the absence of detectable PSA in the serum after treatment being the best measure treatment efficacy.
Minimally invasive RP is done using minimally invasive approaches, such as robotic or laparoscopic surgeries. Robotic surgery now accounts for 80% of all surgeries, with its small incisions and better precision resulting in more rapid recovery, shorter hospital stays and fewer acute complications. The rates of cure and recovery depend on the expertise of the surgeon.
The chances of the cancer recurring depend on the grade, volume and pathologic extent of disease. Patients with organ-confined disease have long-term biochemical relapse-free survival rates of 80 to 90%, while those with locally advanced disease (extraprostatic extension, positive surgical margins, seminal vesicle invasion, and regional lymph node involvement) have an increased risk of recurrence. Disease-free and overall survival rates are even higher since many men with a biochemical recurrence do not have a clinical recurrence of their prostate cancer.
Technical advances have made it possible to give of higher doses of radiation to the tumour while lowering toxicity to healthy tissue.
• Three-dimensional conformal RT (3D-CRT) - 3D-CRT delivers radiation to a three-dimensional volume using appropriate imaging studies and computer software to precisely delineate the prostate gland and adjacent structures.
• Intensity-modulated RT - Intensity-modulated RT (IMRT) is an advanced form of 3D-CRT, which can target a complex and irregular tumour volume. IMRT utilises a beam with varying intensity, in contrast to techniques in which the dose rate is constant.
• Image-guided RT - Image-guided RT (IGRT) uses two- or three-dimensional imaging prior to each treatment to precisely locate the tumor and surrounding organs. IGRT thus minimizes the radiation to normal tissue that would otherwise be required because of changing anatomic relationships.
• Proton-beam RT — Proton-beam RT uses charged particles (protons) to deliver high doses of RT to the target volume while limiting the ’scatter‘ dose received by surrounding tissues. There are only limited data in men with prostate cancer, and the necessary equipment is not widely available.
The goal of RT is to deliver a therapeutic dose of radiation to the tumour while minimising radiation exposure to adjacent healthy tissues. Gastrointestinal and genitourinary complications may occur due to the close anatomic proximity of the prostate gland to the rectum and bladder.
Both external beam RT (EBRT) and brachytherapy are widely used, with results being similar to radical prostatectomy. Assessment of the efficacy of RT relies upon prostate specific antigen (PSA) -- high blood levels of this protein produced by the prostate gland is an indicator of cancer -- measurements to spot biochemical recurrence. But unlike after RP in which the prostate gland has been removed, the presence of residual normal prostate tissue following RT makes PSA levels post-treatment more difficult to interpret.
EBRT uses an external source of radiation to treat the prostate gland and a margin of adjacent healthy tissue. The outcomes with EBRT have improved significantly due to technical advances and the addition of androgen deprivation therapy (ADT) to RT for men with locally advanced cancer. Contemporary EBRT techniques appear to be as effective as radical prostatectomy for localised prostate cancer, with EBRT also being used as additional therapy for men with rising serum PSA after radical prostatectomy.
Brachytherapy potentially maximises irradiation of the tumour while limiting radiation to normal structures by direct implantation of a radioactive source (radioactive seeds) to treat prostate cancer. Another advantage is that it requires a one-time treatment instead of daily therapy as required by EBRT.
In some cases, brachytherapy is combined with EBRT to ensure that an adequate radiation dose is given at the margin of the treatment field.
Cryotherapy uses freezing to kill tumour cells. In early studies, it was associated with high rates of complications but technical advancements have lowered toxicity and increased effectiveness.
High-intensity focused ultrasound (HIFU) uses externally generated sonic waves to create a sharply delineated area of thermal energy that destroys the target tissue. Devices for HIFU are approved in Europe and elsewhere, but are investigational in the US.
Primary hormone therapy * Get as much information as possible from books, support groups and the internet before meeting your doctor, but since this information may not always be accurate, unbiased or relevant to your situation, always crosscheck with your doctor before following medical advice. * Take along a detailed list of questions and record the answers. * Ask about your doctor's experience in treating prostate cancer. * Take along your partner or a friend who can act as your advocate. * Discuss the pros and cons of the different treatments and how they will affect you with your doctor.
Bt itself, primary hormone therapy is used in men seeking active therapy but wishing to avoid the side effects of RP or RT. This approach, however, does not have a role in patients with clinically localised disease.
* Get as much information as possible from books, support groups and the internet before meeting your doctor, but since this information may not always be accurate, unbiased or relevant to your situation, always crosscheck with your doctor before following medical advice.
* Take along a detailed list of questions and record the answers.
* Ask about your doctor's experience in treating prostate cancer.
* Take along your partner or a friend who can act as your advocate.
* Discuss the pros and cons of the different treatments and how they will affect you with your doctor.
Androgen deprivation therapy (ADT) is the preferred initial treatment for men with metastatic prostate cancer. Based upon this, its use to treat men with localised prostate cancer who do not undergo definitive local therapy has gone up.
Antiandrogen monotherapy lowers symptoms of sexual dysfunction, hot flashes and spares bone and muscle mass but raises gynecomastia compared to ADT. Primary antiandrogen monotherapy is not recommended for localised prostate cancer and antiandrogens are not approved as monotherapy to treat advanced prostate cancer in the US.
All treatments can have some risk of side effects, which include with surgery, cryoablation, and radiation resulting in impotence and incontinence. Hormonal therapy, which reduces the amount of testosterone in the bloodstream, usually leads to loss of sex drive and weight gain. The potential consequences of treatment have to be weighed carefully in each case to determine the optimal approach.
With inputs from Dr Prasanna Sooriakumaran, Dr Sonal Grover and Robert Leungwww.nycrobotics.com