Bladder cancer

Bladder cancer is responsible for approximately 3% of all malignancies diagnosed in New Zealand each year. Bladder cancer is more common in men than women and typically affects people over 60 years of age. The main risk factor for this disease is cigarette smoking. Nearly all are transitional cell cancers (arising from the inner lining cells of the bladder). Rarer bladder tumours include adenocarcinoma (usually arising from the urachus) and squamous cancer (associated with chronic inflammation and schistosomiasis).

Bladder cancer at an early stage of growth may not produce any noticeable signs or symptoms. Common signs of bladder cancer include haematuria (bloody urine that looks red or rusty), which is usually painless and may appear only from time to time over a period of months, a burning sensation during urination and a need to urinate often. It is important to note that these symptoms can also be characteristic of urinary tract infection.

When bladder cancer causes noticeable symptoms, these symptoms are usually related to the irritation brought about by tumour growth. Symptoms include urination that is frequent, urgent, painful or difficult. These symptoms are more common among patients with ‘carcinoma in situ' (CIS), cancer that has not spread and is still "in place".
In fact, irritable urination (emptying of the bladder) may be the only noticeable symptom of CIS. As these symptoms are also caused by bacterial infections and stones, tests are important to make an accurate diagnosis especially if they last longer than 2 weeks.

If a bladder tumour blocks a ureter (one of the two tubes that pass urine out of the kidneys and into the bladder), patients may experience pain in the side of the body between the ribs and the top of the hip. In some cases, tumour growth may constrict the urethra (the tube that passes urine from the bladder out of the body) and slow the flow of the urine stream. Bladder cancers may also shed pieces of dead tissue that are then passed out in the urine.

If the tumour has spread beyond the bladder to surrounding tissue, the patient may experience pelvic pain. In addition, metastases from a bladder cancer may cause secondary symptoms, such as bone pain at the site of the new cancer or leg swelling (oedema) due to the involvement of the lymph nodes. Bladder cancer that has progressed to the point of organ invasion and metastasis may eventually cause the patient to lose weight and feel fatigued. Anaemia and high blood levels of metabolic by-products, often due to urinary tract obstruction, may be further indications of late-stage bladder cancer.

Diagnosis

If there is blood in the urine, or any of the other symptoms mentioned are experienced, further test will be required to define the underlying problem.

During a cystoscopy a thin flexible tube with a light and a camera lens is inserted into the urethra and up into the bladder. This is used to look at the inner lining of the bladder and check for any abnormalities or suspicious looking tissue. It is sometimes necessary to take a biopsy that can be examined more closely in a laboratory allowing an accurate diagnosis to be made. This is a quick and relatively painless but important test.
A special dye is injected into your arm that travels through the bloodstream, is filtered by the kidneys and outlines the urinary tract. A CT scan in turn is then performed to image the anatomy and detect any abnormalities in the bladder or urinary tract.

Treatments

There are a number of possible treatments available to patients diagnosed with bladder cancer. These include Surgery, Intravesical instillation treatment, Chemotherapy and Radiation Therapy. A number of treatments may be used in conjunction with each other, typical examples being the use of pre-operative chemotherapy to shrink the tumour or slow its growth, or intra-vesical (into the bladder via a catheter) therapies after localized cystoscopic surgery.

The choice of treatments depends on a number of factors, including your age, general health and the extent of the tumour. It is important to understand what is being recommended and why to decide on the most appropriate course of treatment for you.

Most bladder cancers will need some form of surgical management unless there are clear reasons not to.
Bladder cancers are usually diagnosed with this procedure. This is done under general anaesthetic. A cystoscope is used to visualize the tumour and a wire loop (which is heated using an electrical current) is used to resect it. As such no incision is required. All abnormal tissue and some of the normal tissue next to the tumour are removed to provide information about the stage and grade of the tumour. Chemicals may be instilled in the bladder at the end of the procedure to help prevent recurrence of the tumour.
Often this procedure is curative and leaves the bladder intact and functioning, however the risk of developing further tumours is relatively high and ongoing surveillance may be required for several years in the form of regular flexible cystoscopies and urine tests. The decision to follow this course of treatment depends mainly on the stage and grade of the tumour.
Bladder cancer grading has taken many forms historically. Currently, tumours are considered either high grade (behave aggressively) or low grade (behave less aggressively).
Bladder cancer staging follows the T (tumour) N (nodes) M (metastasis) system:
T stage
The depth of growth of the original primary tumour:
- Ta — localised to the innermost lining of the bladder
- T1 — localised to the innermost lining and underlying stretchy tissue
- T2 — growth into bladder muscle underlying the stretchy tissue
- T3 — growth into fatty tissue outside the bladder
- T4 — growth into other organs directly or the walls of the pelvis
N stage
Reflects whether lymph nodes distant to the bladder are involved with disease.
M stage
Reflects whether other organs and tissues distant to the bladder are involved with disease.
As a general rule, cancers which are localized to the innermost lining and stretchy tissue layers of the bladder are managed with TURBT and sometimes intravesical therapies whereas those that grow more deeply or fail to respond to these measures are managed with more radical treatment. Once the disease has spread to other parts of the body it is managed with palliative (relief giving but non-curative) treatments such as chemotherapy or radiotherapy.
For women, a standard form of surgery is a Radical Cystectomy, which involves cutting away the entire bladder and associated tissues, with Lymphadenectomy (removal of the lymph nodes within the pelvis). Radical cystectomy in women includes removal of the uterus, Fallopian tubes, ovaries, anterior vaginal wall (the front of the birth canal), and urethra. It therefore may affect sexual and reproductive function.
In men, a common surgical procedure is called Radical Cysto-Prostatectomy, which involves the removal of the bladder and prostate, with Lymphadenectomy and may also effect sexual and reproductive function.
The kidneys make urine by filtering the blood to remove toxins and any excess water. This then passes through the ureters into the bladder where it is held until ready to void.
Because some types of cancer can only be remedied by removing the bladder, another way must be found in order for the body to discharge urine. These procedures are called urinary diversions.
The most common diversion is called an Ileal Conduit – this involves taking a piece of bowel and forming a ‘pipe' that is inserted where the bladder once was. The conduit then carries the urine from the ureters out onto the skin of the abdomen where the conduit ends in a stoma – a small opening. Urine is then emptied into a plastic bag attached to the skin, which can be emptied when convenient.
Other forms of diversion involve the formation of an internal pouch (usually referred to as a neobladder) made out of part of the bowel. The pouch is then connected to the top of the urethra (outflow pipe) but acts solely as a reservoir (compared with the bladder which is a reservoir but also a pump). Some people are able to void with this reconstruction but others may need to pass a catheter through the urethra on a regular basis to empty the pouch.
This is a large operation and requires significant planning and recuperation time. The most appropriate form of urinary diversion should be discussed thoroughly prior to surgery.
Intra-vesical treatment involves flushing the bladder with chemotherapy (cell killing treatment) or immunotherapy (immune system stimulating treatment) to remove residual tumour cells following surgery. The chemicals are placed directly into the bladder in order to prevent the tumour recurring or to prevent it from invading the deeper layers of the bladder wall. This way of delivering the treatment helps to keep general side effects in the rest of the body to a minimum.