- Prostate brachytherapy
=What is brachytherapy?=
Brachytherapy is a type ofradiotherapy , or radiation treatment, offered to certain cancer patients. There are two types of brachytherapy – high dose-rate (HDR) and low dose-rate (LDR). LDR brachytherapy is the type that is most commonly used to treatprostate cancer ; it may sometimes be referred to as ‘seed implantation’ or it may also be called ‘pinhole surgery’.LDR prostate brachytherapy
In LDR brachytherapy, tiny radioactive particles the size of a grain of rice (see . These particles are known as ‘seeds’, and they can be inserted linked together as strands, or individually. Because the seeds are inserted or implanted directly into, or very close to, the tumour, they deliver high doses of radiation to the tumour without affecting the normal healthy tissues around it. This means that the procedure is less damaging than conventional radiation therapy, where the radioactive beam is delivered from outside the body and must pass through other tissues before reaching the tumour.
LDR prostate brachytherapy (seed implantation) is a proven treatment for early, localised prostate cancer (when the cancer is contained within the prostate). Kupelian PA, Potters L, Khuntia D et al. Radical prostatectomy, external beam radiotherapy less than 72 Gy, external beam radiotherapy ≥72 Gy, permanent seed implantation, or combined seeds/external beam radiotherapy for stage T1-T2 prostate cancer. International Journal of Radiation Oncology Biology Physics 2004;58:25–33] [Potters L, Morgenstern C, Calugaru E et al. 12-year outcomes following permanent prostate brachytherapy in patients with clinically localized prostate cancer. The Journal of Urology 2005;173:1562–1566] Under a general anaesthetic, the radioactive seeds are injected through fine needles directly into the
prostate , so that the radiotherapy can destroy the cancer cells. The seeds are permanently implanted, so they remain in place but gradually become inactive as the radioactivity decays naturally and safely over time. [The American Brachytherapy Society: www.americanbrachytherapy.org] Unlike traditional surgery, LDR brachytherapy requires no incisions and is normally carried out as a day-case procedure. Sometimes a single overnight stay in hospital is required. Patients usually recover quickly from LDR brachytherapy, which means that most men can return to work or normal daily activities within a few days. As described below, LDR brachytherapy has a good side-effect profile with less risk ofincontinence orimpotence than other treatment options,Frank SJ, Pisters LL, Davis J et al. An assessment of quality of life following radical prostatectomy, high dose external beam radiation therapy and brachytherapy iodine implantation as monotherapies for localized prostate cancer. The Journal of Urology 2007;177:2151–2156] and is becoming an increasingly popular alternative to major surgery (conventional radical prostatectomy or laparoscopic (keyhole surgery) radical prostatectomy).What does LDR prostate brachytherapy treatment involve?
When LDR prostate brachytherapy (seed implantation) is carried out, an
ultrasound probe is inserted into the back passage (rectum ), and images from this probe are used to assess the size and shape of the ) to ensure that all cancer cells present in the prostate have been completely treated.Once in place, the seeds slowly begin to release their radiation. While the seeds are active, the patient must observe some basic precautions. Travel and contact with adults are fine; however, for the first two months following seed implantation, small children and pregnant women should not be in direct contact with the patient for prolonged periods – for example children should not sit on the patient’s knee for any length of time. Sexual intercourse can start again within a few weeks. Very occasionally a seed can be expelled in the semen on ejaculation; if this does happen, it will usually occur in the first few ejaculations, so it is advisable to use a condom for the first two or three occasions of intercourse following LDR brachytherapy. Ash D, Flynn A, Batterman J et al. ESTRO/EAU/EORTC recommendations on permanent seed implantation for localized prostate cancer. Radiotherapy and Oncology 2000;57:315–321]
Patients can usually get back to normal activities and work within a few days. They should expect to be seen for follow-up after four to six weeks, and then every three months for a year, six-monthly up to five years, then annually.Salembier C, Lavagnini P, Nickers P et al. Tumour and target volumes in permanent prostate brachytherapy: a supplement to the ESTRO/EAU/EORTC recommendations on prostate brachytherapy. Radiotherapy and Oncology 2007;83:3–10] Ash D, Flynn A, Batterman J et al. ESTRO/EAU/EORTC recommendations on permanent seed implantation for localized prostate cancer. Radiotherapy and Oncology 2000;57:315–321]
Who can have LDR prostate brachytherapy?
LDR prostate brachytherapy (seed implantation) is recommended as a treatment for patients whose cancer is at an early stage (cancer stages T1 to T2), and which has not spread beyond the prostate (localised disease).Ash D, Flynn A, Batterman J et al. ESTRO/EAU/EORTC recommendations on permanent seed implantation for localized prostate cancer. Radiotherapy and Oncology 2000;57:315–321] National Institute for Clinical Excellence. Prostate cancer diagnosis and treatment (2008). NICE clinical guidelines 58. London: National Institute for Clinical Excellence] Doctors use a combination of factors such as cancer stage and grade, PSA level and Gleason score to help them decide if a patient is suitable for LDR brachytherapy. Patients should ask their doctors about the results of these different tests and how they influence the type of treatment they may be offered.Ash D, Flynn A, Batterman J et al. ESTRO/EAU/EORTC recommendations on permanent seed implantation for localized prostate cancer. Radiotherapy and Oncology 2000;57:315–321] National Institute for Clinical Excellence. Prostate cancer diagnosis and treatment (2008). NICE clinical guidelines 58. London: National Institute for Clinical Excellence] LDR brachytherapy in combination with external beam radiotherapy may also be recommended for patients with later-stage cancer and higher PSA level and Gleason score.Ash D, Flynn A, Batterman J et al. ESTRO/EAU/EORTC recommendations on permanent seed implantation for localized prostate cancer. Radiotherapy and Oncology 2000;57:315–321]
What are the risks/benefits of LDR prostate brachytherapy?
Since its introduction in the mid-1980s, prostate brachytherapy (seed implantation) has become a well-established treatment option for patients with early, localised disease. In the US alone, over 50,000 eligible prostate cancer patients a year are treated using this method.The Prostate Brachytherapy Advisory Group: www.prostatebrachytherapyinfo.net] Awareness of this treatment choice has now spread to other parts of the world, and there is widespread and rapidly growing use of the technique. In the UK alone, brachytherapy has been used for over 10 years and thousands of patients have been treated.
Clinical benefits
LDR prostate brachytherapy (seed implantation) on its own has been shown to be highly effective for the treatment of early prostate cancer. [Khaksar SJ, Laing RW, Henderson A et al. Biochemical (prostate-specific antigen) relapse-free survival and toxicity after 125I low-dose-rate prostate brachytherapy. BJU International 2006;98:1210–1215] The rate of survival with no increase in average PSA levels after LDR brachytherapy is similar to that achieved with external beam radiotherapy and radical prostatectomy.Kupelian PA, Potters L, Khuntia D et al. Radical prostatectomy, external beam radiotherapy less than 72 Gy, external beam radiotherapy ≥72 Gy, permanent seed implantation, or combined seeds/external beam radiotherapy for stage T1-T2 prostate cancer. International Journal of Radiation Oncology Biology Physics 2004;58:25–33] However LDR brachytherapy has a lower risk of some of the complications associated with these other treatment options.Frank SJ, Pisters LL, Davis J et al. An assessment of quality of life following radical prostatectomy, high dose external beam radiation therapy and brachytherapy iodine implantation as monotherapies for localized prostate cancer. The Journal of Urology 2007;177:2151–2156] It is important to remember that many men in this age group die from diseases unrelated to their prostate cancer.
ide-effects
LDR prostate brachytherapy (seed implantation) is a very effective treatment for early, localised prostate cancer, with patients rapidly returning to normal activities. [Langley SE, Laing R. Prostate brachytherapy has come of age: a review of the technique and results. BJU International 2002;89:241–249] Although patients may experience problems (
urinary incontinence or difficulty withurination ) for the first 6 months or so after their implant, these usually settle down and lasting problems are rare, only occurring in about 1–2% of patients. [Crook J, Fleshner N, Roberts C, Pond G. Long-term urinary sequelae following 125Iodine prostate brachytherapy. The Journal of Urology 2008;179:141–146] Some patients (less than 10%) report an increase in bowel problems (diarrhoea or urgency of the bowels), but again this usually settles down without further treatment.Buron C, Le Vu B, Cosset JM et al. Brachytherapy versus prostatectomy in localized prostate cancer: Results of a French multicenter prospective medico-economic study. International Journal of Radiation Oncology Biology Physics 2007;67:812–822]Erectile dysfunction (difficulty getting and/or keeping an erection; impotence) is another side-effect associated with all treatments for prostate cancer. Other treatments for prostate cancer cause problems with erectile dysfunction in 30–60% of men (as seen in ), but these problems are much less common after LDR brachytherapy, and only occur in about 10–30% of men under the age of 60 years, who were potent before treatment.The Prostate Brachytherapy Advisory Group: www.prostatebrachytherapyinfo.net]
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