Radiotherapy for Localised Prostate Cancer
Radiotherapy utilizes radiation beams to target and eliminate cancer cells. Prostate cancer can be treated using either external or internal radiotherapy methods.
The testicles
The testicles are two small, oval-shaped organs located below the penis, enclosed in a skin pouch called the scrotum.
Image of the testicles (cruk)
Starting from puberty, the testicles begin producing sperm. Inside the testicle, small tubes come together to form the epididymis, a single tube that becomes wider as it exits the testicle. This wider tube is known as the spermatic cord.
The spermatic cord leads to a short passage called the ejaculatory duct, which opens into the urethra, the tube that carries urine and semen out of the body through the penis.
Testosterone:
The testicles produce the hormone testosterone, which is responsible for developing male characteristics such as:- A deeper voice
- Facial hair growth
- Increased muscle mass
- The ability to achieve an erection
- Male sexual drive (libido)
Where does testicular cancer start:
The testicles consist of various cell types, and the kind of cancer you have depends on the specific cell where it begins. Most testicular cancers arise from germ cells, which are responsible for producing sperm. Doctors classify germ cell cancers into two main types:- Seminoma
- Non-seminoma
External Beam Radiotherapy:
External beam radiotherapy is an effective treatment for prostate cancer at stages T1, T2, and T3. Typically, before starting radiotherapy for localized prostate cancer, hormone therapy may be administered for a few months. This helps shrink the prostate, making it easier to target during treatment. Hormone therapy is discontinued once radiotherapy is completed.
In cases of T3 (locally advanced) disease, hormonal therapy may continue for two to three years following radiotherapy. External beam radiotherapy involves daily treatments over two to six weeks, with sessions lasting about 10 minutes each day, five days a week.
Before initiating external beam radiotherapy, a CT scan is conducted to precisely identify the treatment area. This region may be marked with a small medical tattoo for accuracy during treatment.
Prostate movement due to breathing can sometimes lead to challenges in targeting during radiotherapy. To address this issue, small gold markers known as fiducial markers (approximately 2mm in size) may be implanted in the prostate. These markers facilitate precise targeting of the prostate, even if it moves slightly during treatment. Fiducial markers remain in the prostate permanently without causing any medical issues.
There are two types of External Radiotherapy
Conformal Beam Radiotherapy :
This method precisely directs radiation to cancerous areas using advanced 3D computerized imaging, minimizing the impact on healthy surrounding tissues.
Intensity Modulated Radiotherapy ( IMRT):
This technique evaluates the shape of the cancer and administers a higher radiation dose to the central part of the tumor while minimizing exposure to surrounding healthy tissues.
IMRT can also adjust the radiation beam to avoid affecting non-targeted structures, making it particularly beneficial for treating men with extensive prostate cancer that extends to the prostate surface or seminal vesicles.
A more advanced form of IMRT utilizes a machine known as rapidarc, which rotates around the body to deliver treatment more efficiently. This reduces treatment duration and limits the total radiation dose applied.
Internal Radiotherapy ( Brachytherapy)
A) Permanent Brachytherapy
This form of radiotherapy treatment involves implanting small radioactive seeds directly into the prostate through a minor surgical procedure. Known as permanent brachytherapy, these seeds emit radiation that targets and destroys cancer cells. Typically, this treatment requires only one or two hospital visits and generally does not necessitate hormonal therapy prior to administration.
Brachytherapy is commonly employed for the treatment of T1 and T2 prostate cancer stages.
B) Non-Permanent Brachytherapy:
This radiotherapy technique entails placing temporary radioactive rods into the prostate gland. Unlike permanent brachytherapy, where radioactive seeds remain indefinitely, these rods are designed to deliver targeted radiation for a specific treatment period.
c) High Dose Brachytherapy:
In this approach, temporary brachytherapy is integrated with external beam radiotherapy to enhance the treatment efficacy for prostate cancer.
2.3 : Other Radiotherapy Technics :
Other radiotherapy methods, though less prevalent, may be accessible in select locations across the India.
Stereotactic Radiotherapy (Cyber Knife):
Advanced computer imaging allows for precise delivery of higher doses of radiotherapy, thereby shortening the required treatment duration.
Proton Beam therapy :
External beam radiation delivers its highest radiation dose shortly after entering the skin, as it traverses toward the tumor, and again as it exits through and beyond the tumor.
Proton Beam Therapy utilizes a different form of radiation that can be aimed directly at the tumor site, ceasing energy release beyond the prostate. It is capable of delivering most of its energy at precise depths.
Advocates of Proton Beam Therapy suggest it may minimize damage to nearby healthy tissue.
While Proton Beam Therapy has been employed for challenging cancers, it is not currently a standard treatment for prostate cancer in India.
Pencil Beam Radiotherapy:
Pencil Beam Radiotherapy represents a highly precise approach within proton beam therapy, employing an ultra-thin beam of radiation specifically for treating prostate cancer.
2.4: Possible Side effects of radiotherapy:
a) Erectile Disfunction:
Radiotherapy may impact the nerves around the prostate responsible for controlling erections. Various treatments are available for erectile dysfunction.
b) Urinary Problems:
Radiotherapy typically does not result in urinary incontinence. However, it can occasionally cause the urethra (the tube that carries urine through the penis) to narrow. This narrowing can make urination difficult and usually happens several years after the treatment.
c) Bowel Problems:
In a small percentage of men, radiotherapy can irritate the lining of the rectum (back passage). This inflammation might be temporary, but it can also be permanent in some cases. It can lead to bleeding from the rectum or cause men to need to pass stool (poo) more frequently.
Next Steps:
Following radiotherapy, men will undergo routine blood tests to monitor their PSA levels.
If the cancer recurs after radiotherapy, a prostatectomy (surgical removal of the prostate gland) is generally not advised. Instead, alternative treatments like HIFU (High-Intensity Focused Ultrasound) or Cryosurgery may be proposed to manage the disease.
Daignosis
If you have any symptoms, your first step is usually to visit your GP. They will discuss your symptoms with you and conduct an examination. Based on their findings,
Treatment options
A team of healthcare professionals (multidisciplinary team) will determine your treatment plan. Most people undergo surgery to remove the affected