Bladder cancer is a malignant tumor in the bladder. It is particularly common in industrialised countries. Most bladder cancers are superficial and limited to the mucosa. However, bladder cancer may spread to the bladder wall and metastasise to the liver, lungs, bones, etc. Approximately 20–25% of all bladder cancers invade muscular layers. Bladder cancer recurrence risk is high, which is why the patients must be followed up for the rest of their lives.
Risk of disease
Similar to many other types of cancer, the risk of developing bladder cancer increases with age. Smoking and occupational exposure to chemicals (aromatic amines) are the most important factors that increase the risk of bladder cancer. The risk of bladder cancer has decreased thanks to efficient protective equipment worn by industrial workers today. In addition, exposure to cancerogenic substances in industry is closely monitored to prevent exceeding of limit values. If occupational exposure can be demonstrated, bladder cancer is considered as a compensable occupational cancer. Bladder cancer may also be due to a hereditary cause.
The usual first symptoms of bladder cancer include haematuria (blood in the urine) and pain urinating. If the tumor prevents the flow of urine from the kidneys to the bladder, this may lead to kidney damage. In that case, the patient usually feels pain in the kidney area. A tumor obstructing the urethra causes great difficulty urinating.
When a bladder tumor is suspected, the basic examinations include analysis of the urine to detect haematuria, cytological examination of urine and cystoscopy (an examination of the inside of the bladder). The most common imaging examinations include a urography (x-ray examination) and ultrasound scan of the urinary tract. Increasingly often, a CT scan (CT urography) is performed to examine local spreading of the cancer.
This is followed by an ultrasound scan of the urinary tract. It reveals any large tumors in the bladder and alterations in the kidneys. A contrast-enhanced urography of the kidneys is also one of the first examinations usually performed. It helps to ensure that there are no tumors or blockages in the upper urinary tract. Regardless of what other examinations are conducted, the doctor always performs a cystoscopy.
Prior to transurethral resection, a CT scan of the body is usually performed if it is suspected that the cancer has invaded muscle.
There are different treatment options for bladder cancer, used alone or in combination with each other. Bladder cancer takes many forms and its prognosis varies. Therefore, accurate staging and histopathological classification performed by a pathologist are important with regard to the choice of treatment.
If the tumor is superficial, that is, it has not spread from the bladder mucosa to the muscular tissue of the bladder, it is treated with transurethral resection of the bladder (TURB). A cytoscope is inserted into the bladder through the urethra and the tumor is scraped or burned away.
If the cancer has spread to the muscular tissue of the bladder or there is a risk of this, radical surgery may be chosen. This means partial or complete removal of the bladder and removal of the prostate. There are two alternatives for arranging the passing of urine after a radical operation. A urostomy means that urine is collected via a stoma into a urostomy pouch. Another alternative is to use a part of the intestine to construct a replacement bladder.
Depending of the type of cancer, the size of the tumor and possible metastases, radiotherapy and intravenous chemotherapy may also be necessary. Chemoradiotherapy can be as successful as traditional surgery.
Superficial bladder cancer with a good prognosis is treated with transurethral resection of the tumor. In connection with the operation, or immediately following it, a bladder instillation of medication is administered once in order to decrease the risk of recurrence. If a superficial tumor has a higher recurrence risk, the patient is treated postoperatively with repeated instillations of medication.
A male patient’s prostate is normally removed in the operation, but today the urethra is usually saved. A female patient’s urethra is removed, and usually the uterus and adnexa are also removed. If surgical treatment is not possible, for reasons such as the patient’s poor physical condition or the location of the tumor, the cancer is treated with radiotherapy.
At the time of diagnosis, metastases are found in a small minority of patients (approximately five per cent). In this event, it may be decided not to perform a bladder removal operation, and the patient is referred to radio- or chemotherapy. In methastasised cancers, radiotherapy can be administered as palliative treatment to relieve symptoms caused by pain, discharge, a large tumor or urinary tract blockage. A metastatic cancer is treated with chemotherapy. As a result, metastases usually decrease in size and symptoms of the disease are alleviated. Chemotherapy extends the survival of a patient with metastatic cancer by six months on average.