Introduction
The bladder is the most common site of cancer in the urinary system. Bladder Cancer is much more common in men – the risk by age 85 is 1 in 44 for men, compared to 1 in 154 for women. Bladder cancers usually arise from the cells lining the bladder.
What are the symptoms?
The most common symptom is that of blood in the urine (haematuria), which is usually painless. This is why all patients with blood in the urine have to be investigated, even though the cause is non-cancerous in most cases. If the bleeding is heavy, blood clots can form in the bladder and patients can go into urinary retention (unable to pass urine).
Other symptoms are the frequent need to pass urine and burning when passing urine. In advanced cases, patients present with cancer that may have spread to other organs (commonly to bones causing bone pain) or blockage of the kidneys causing kidney failure.
There is no screening test for bladder cancer.
What are the risk factors?
- Smoking increases the risk of bladder cancer by 2 to 4 fold. By stopping smoking, the risk slowly reduces to baseline in 20 to 30 years.
- Chemical exposure to dye increases the risk of bladder cancer. Some occupations with an increased risk are textile workers, petroleum workers, painters, hairdressers, and tire / rubber workers.
- Some chemotherapy drugs.
- Radiation treatment for other pelvic cancer.
What are the investigations?
Investigations are aimed at diagnosing bladder cancer and determining how advanced it is (staging and grading). As the bladder lining is made of the same cells as the inside of the kidneys and ureters (tubes draining the kidneys to the bladder), it is also necessary to rule out cancer there.
Diagnosing the bladder cancer
A urine test can be done to look for cancer cells. Blood tests are also done to check the blood count, kidney function, and screen for liver enzyme abnormalities (which may be abnormal if there is a spread of cancer to the liver).
X-ray imaging with a CT scan (with intravenous contrast) is useful to make sure there are no other cancers in the kidneys or ureters. It can also look for kidney obstruction or evidence of the spread of cancer beyond the bladder.
Sometimes a patient may not have intravenous contrast for medical reasons and the CT scan would not provide the necessary information needed. In this case, a procedure done under general anaesthetic (retrograde pyelogram) may be done. This involves injecting contrast up the ureters and taking some x-ray pictures, during a cystoscopy (inspection of the bladder with a tubelike camera).
Staging
A chest x-ray and a bone scan may be ordered if there is suspicion that the cancer may have spread beyond the bladder. Together with the CT scan, this is described as staging of the cancer.
The most important test is a cystoscopy, during which bladder biopsies of suspicious areas may be done. If there is an obvious bladder cancer, this can be resected (transurethral resection of bladder tumour – TURBT) and the specimen sent off for analysis by a pathologist. This analysis can determine how aggressive the cancer cells are (grading of cancer), and this is important because subsequent treatment would depend on it. In particular, bladder cancer is categorised either as a superficial or invasive cancer.
What other treatments are needed after the bladder tumour is resected?
The treatments needed depend on whether the cancer is superficial or invasive.
Superficial bladder cancer
For superficial bladder cancer, the patient is put on a long-term surveillance program, which involves inspecting the bladder for recurrences with a cystoscopy at regular intervals. Some patients may benefit from regular treatments of infusion of medications into the bladder via a catheter. These medications coat the bladder lining, kill the cancer cells, and are drained from the bladder via the catheter after 1 to 2 hours of treatment (see bladder instillation therapy).
Invasive bladder cancer
For invasive bladder cancer, it must first be determined if there is a spread of cancer beyond the bladder (metastatic cancer).
If the cancer is still confined to the bladder, a major operation to remove the bladder (radical cystectomy) may be done. During this operation, the ureters are joined to a segment of the small bowel that is either fashioned as a stoma (which drains directly from the abdominal wall into a bag) or as a neobladder (artificial bladder; the patient still retains some normal urinary control). Sometimes, chemotherapy may be given to shrink the cancer before surgery. In patients who are not fit for surgery, radiotherapy and chemotherapy may be given to control bleeding from the bladder and to control the cancer respectively.
If there is evidence that the cancer has spread beyond the bladder, it is no longer curable. Surgery is not appropriate in this case and chemotherapy is the treatment of choice to control the cancer.