Understanding Prostate Cancer

The prostate is a small organ, typically described as being walnut sized, present only in males. It lies at the base of the urinary bladder; the passage for excreting urine i.e. the urethra, passes through it. The size of the prostate, specifically the part adjacent to the urethra, increases in most men as they grow older. This non cancerous condition is called benign prostatic hypertrophy(BPH). The other reason for increase in size is prostate cancer.





q. What complaints or problems are an indication that the prostate requires to be investigated?
a. Presence of blood in the urine, frequent urination both during the day and/or night and inability to hold urine once the urge to pass has been felt, should prompt a visit to the doctor. Similarly, the inability to pass urine or the development of impotence should lead to medical consultation.  It is important to stress that these symptoms are not a definite indication of prostate cancer, but instead of a problem in the prostate. Besides prostate cancer, benign enlargement of the prostate (BPH) or an inflammation/ infection of the urinary tract may also give rise to the above symptoms.
Symptoms of a more general nature, such as weight loss and low backache are also important.
It is essential to know that prostate cancer arises most often from a part of the gland that is away from the urinary passage, and may hence produce no symptoms at all.





q. What steps are to be taken once symptoms relevant to a prostate problem have been noted?
a. A combination of steps are to be taken in consultation with a doctor. These are the measurement of Prostate Specific Antigen (PSA) in the blood and a Digital Rectal Examination (DRE), with or without an Ultrasound examination of the urinary tract. The ultrasound examines, among other parameters, the size, shape  and abnormalities of the prostate gland, as well as the amount of urine within the urinary bladder, before and after passing urine. DRE is a physical examination of the prostate via the rectum.
In case prostate cancer is suspected in the above investigations, a biopsy of the prostate gland may be planned. When the suspicion is very strong, the doctor may choose to get an MRI examination done even before a biopsy, so as to carry out the assessment before creating artifacts by the biopsy procedure. 



q. What is PSA?
a. PSA is a protein  produced by the  prostate gland. The blood level of this substance increases in the presence of prostate cancer; this fact is used to diagnose prostate cancer as well as to monitor its status. This is true of most but not all prostate cancers. PSA blood levels may also increase, to small degree, in benign enlargement of the prostate (BPH) or prostatic inflammation, as well as after particular activities and medical interventions.



q.How is prostate cancer diagnosed?

a.Once prostate cancer is suspected on the basis of a raised PSA value and an abnormal finding on clinical examination, a needle biopsy is performed via the rectal route, using an ultrasound to guide the needle into the prostate. Multiple cores of tissue are drawn out and examined under the microscope to document the presence of cancer cells. In addition, the grade of the cancer is determined, which is in turn a measure of the aggressiveness of the cancer


q.What happens after diagnosis?
a.The stage of the cancer is determined; broadly speaking the cancer may be confined to the prostate, be locally advanced or may have spread outside the confines of the prostate and its vicinity.

Following this, organ confined and locally advanced cancers are classified into low, intermediate and high risk categories. One of three options of treatment may be chosen, on the basis of multiple factors, the stage and grade of cancer, age, health status and desire of the patient.

Patients who are noted to have prostate cancer that has spread to other organs are treated with hormone therapy; occasionally they may also require chemotherapy.



q.Which are the three treatment options, mentioned above, for local and locally advanced prostate cancer?


a.Surgical removal of the diseased prostate gland, along with seminal vesicles that are attached to it as well removal of lymph glands in the pelvis is curative for early prostate cancer. It is now possible to perform this surgery, called radical prostatectomy, using the assistance of a robot that magnifies the surgical field up to 40 times and also allows the surgeon to reach difficult to access regions in the pelvis, while restricting discomfort and hospital admission time of the patient.

The cancer can also be treated non invasively using radiotherapy, i.e., x-rays.  A combination of sophisticated comuputerised planning and equipment called linear accelerator allow the radiation oncologist to focus radiotherapy on the prostate accurately while avoiding radiation to neighbouring urinary bladder and rectum. The technique used is Image Guided Radiotherapy ( IGRT) wherein the prostate�s position is confirmed prior to daily treatment; RapidArc or Intensity Modulated Radiotherapy ( IMRT) help ensure that radiotherapy dose to adjacent normal organs is minimized. This method of treatment is effective for organ confined as well as locally advanced prostate cancer, in addition to also working for failure after surgery or in post operative situations where the risk of failure is deemed high.  Radiotherapy is administered along with hormone therapy.




RapidArc Radiotherapy Plan for Prostate Cancer




Patients with poor life expectancy because of advanced age or ailments such as a heart disease or diabetes and the presence of low risk prostate cancer, it may be reasonable to follow a treatment plan which primarily aims at keeping the disease under observation, with regular assessment to document its growth.  This is called active surveillance. Treatment is carried out if the disease appears to progress. This option has to be chosen   very carefully as while this approach avoids unnecessary treatment, it also results in a small chance that the cancer may progress into an incurable stage in between two assessments.



q.How is prostate cancer treated by you?

a. My patients with prostate cancer that has remained confined to the prostate or its vicinity are typically treated in 28 sessions. This treatment is delivered over 5 - 6 weeks. In certain situations, such as when  a patient has many urinary complaints, a more protracted course of radiotherapy is advised.
Radiotherapy is administered in a carefully controlled condition, with due attention to positioning of the patients and application of protocols for bladder filling and rectal emptying, under daily image guidance.

In addition, patients receive Androgen Deprivation Therapy, i.e. drugs to prevent formation of the male hormone. This therapy may last for a period ranging from 6 months to 2 years, depending on the nature of the patient's ailment.

Patients are able to carry on their daily routine during radiotherapy. Some patients may experience urgency while passing urine, and occasionally, some may also encounter mild burning sensation while passing urine. Discomfort in passing stools occurs rarely. These symptoms are transient.






Radiotherapy for Hepatocellular Carcinoma

Patients suffering from Hepatitis B and C  infection and, or, alcohol induced liver cirrhosis,  are more prone to develop hepatocellular carcinoma, i.e. liver cancer. Aflatoxin toxicity,   as well as fatty liver, may also make a person more prone to this aggressive cancer, considered among the top few causes of dying due to cancer.

Treatment of this cancer is linked to the general health status of the patient, the health of his liver, the number and size of the cancerous lesions, as well as the presence of the tumour in major vessels, nodes or other organs of the body.

Resection of a part of the liver, or removal of the entire liver, accompanied by transplanting the liver of a donor, has a high chance of resulting in cure. This treatment is, however, generally reserved for patients who  either have a  moderately sized single tumour, or  small tumours  less than 3 in number,  with good general health, and good functional capacity of the liver.

Patients with more extensive tumours, which are still confined to the liver, may undergo local treatments, with a view to controlling the tumour. This is done with the intent of making the  tumour amenable to  surgery  (downstaging), to buy time while the patient is on a waiting list for a donated liver, or, in some situations, as the sole therapy to prolong the life of a patient.

One of the therapies that is used is Trans Arterial Chemo Embolisation (TACE).  Performed by interventional radiologists, TACE involves  insertion of a catheter in the  blood vessel feeding the tumour, instillation of chemotherapy, locally into the tumours, and then closing off the blood supply to the tumour, thus allowing the drug to act locally.



Radiotherapy is the treatment of cancer using X rays. Various sophisticated techniques, that are an integration of advances in  computer software and in treatment machines called linear accelerators, enable safe radiotherapy. Tumours can be targeted better, notwithstanding their irregular shape, proximity to vital organs or movement with respiration or other bodily functions.

Radiotherapy was earlier considered ineffective for liver cancers; improvement in radiotherapy techniques has resulted in improvement in the therapeutic ratio, i.e. the chance of curing the tumour vis a vis the risk of damaging normal organs. With this improvement, high doses of radiotherapy can be administered, leading to  better chances of controlling tumours. Techniques used for this treatment are Intensity Modulated Radiotherapy ( IMRT) and  Volume Modulated Radiotherapy (VMAT), also called RapidArc. These treatments are delivered under image guidance, i.e. the patient is scanned, prior to each radiotherapy session, on the treatment couch itself, for accuracy. This is called Image Guided Radiotherapy ( IGRT). Since, with these mechanisms, the tumour is targeted accurately and the  bowel and normal liver spared well, very high doses of radiotherapy may be delivered in limited number of sessions; this is called Stereotactic Ablative Radiosurgery (SABR) or Stereotactic Body Radiotherapy  ( SBRT).



Stereotactic Ablative Radiosurgery dose colour wash for a lesion in the liver ( outlined in red).
Radiosurgery may be administered as the sole therapy for patients too unwell for surgery. It may also be used as bridge therapy for patients on a waitlist for liver transplant. This has the twin role of preventing progression during the waiting period as well as identifying patients with aggressive tumours that should not be treated with aggressive surgery, anyway.

Another application is as a treatment for patients with a portal vein tumour thrombus ( PVTT). Patient with any vascular involvement are thought to have a poor prognosis. Adding radiotherapy to the treatment protocol, alone , or along with TACE , is thought to improve the outcome for some patients suffering from HCC with PVTT. 

The treatment of HCC using  SABR/SBRT or the more protracted SHORT typically takes 2 - 3 weeks. In case surgery is planned following radiation, it may be performed anytime from 2 weeks to 6 months later.

In conclusion,  surgery is the ideal treatment for HCC. Non surgical options like TACE and SABR/SHORT help prepare patients for surgery as well as offer a possibility of controlling the disease for sometime, in case surgery is not possible.









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