I. BLADDER
Bladder is the organ that stores urine after its formation by the kidneys. It consists of three layers: a lining of mucous membrane, called epithelium; a midway layer of involuntary muscle, with fibers arranged in three layers, each running in an unlike direction; and an outer layer of connective tissue, roofed by the peritoneum above and to the back and blending with the connective tissues of the body wall in front and below. Urine enters the bladder from the kidneys all the way through two ureters and is discharged through the urethra. The openings of the ureters lie in the basal part of the bladder, each about 3.8 cm from the opening of the urethra, which is located in the midline of the bladder at its lowest point. Average normal capacity of the adult bladder is about half a liter.
II. TYPES OF BLADDER CANCER
Bladder cancer is the most commonly encountered primary tumor of the urinary tract. The incidence is 6 to 8 percent of all male cancers but is lower in the female at 2 to 3 percent, while the male to female ratio is about 2.5: 1. It is predominantly a cancer of the elderly with highest incidence in the 60 to 70 year age group, median age at presentation being about 69 years. Cigarette smoking is the commonest conferring a two to six fold increased risk.
III. METHODS OF STAGING
At the time of presentation one third of cancers will have multifocal disease and one third is invasive. Initial imaging may have already diagnosed a bladder mass, however, as imaging is not sufficiently specific, in all cases the diagnosis needs to be confirmed by endoscopy and biopsy. Tissue analysis not only confirms the cell type but also the malignancy is further subgraded into well differentiated, low grade tumours, moderately differentiated tumors or badly differentiated high grade tumors. The higher grades have a much poorer prognosis and greater likelihood of recurrence. The five year survival for a patient with a grade one tumor is 80 to 95 percent, however, this falls to around 60 percent with a grade three cell type. Further information is gained from the depth of invasion shown by the biopsy sample. This allows the disease to be considered in two broad categories: superficial and invasive. The depth of invasion has a direct bearing on the five year survival rate, the rate being greater than 80 percent for patients with tumors confined to the mucosa or submucosa but between 40 and 60 percent depending on whether the muscle is breached and the perivestical fat is involved. Depth of invasion also influences the treatment options, in broad terms, patients with the superficial tumor; the tumors confined to the mucosa and the superficial muscle layer, are treated with local resection and maintained on surveillance for recurrent disease, with additional intravesical therapy as necessary. Patients with deeper invasive tumors are treated with the more radical options of bladder resection or radiotherapy. This is an oversimplification of what is, in practice, a complex clinical problem and one that is evolving all the time, however, it serves a make the point that accurate microscopic and macroscopic staging of bladder transitional cell carcinoma is central to the management of this disease.
IV. SIGNS AND SYMPTOMS
One of the most common signs of bladder cancer is blood in the urine. In the majority of cases, this includes microscopic amounts of blood that can only be picked up by the laboratory on a urine sample. Some people will have so much bleeding that it turns the urine pink or red. Obviously, gross hematuria is not normal, and because it is so alarming, it will often prompt quicker evaluation. Microscopic hematuria though is also not normal and should always be evaluated by a urologist. Even if the blood in the urine clears up on its own, it still always needs to be evaluated. The absence of pain does not mean that there is no need for concern.
Hematuria is not the only warning sign, however, depending on its location within the bladder; the tumor may interfere with the normal functioning of the bladder, which could manifest as irritative voiding symptoms. These symptoms include urinary urgency and urinary frequency. Urgency is the feeling of a sudden, compelling desire to urinate that is difficult to make go away. Frequency means going to the bathroom eight or more times per day. Urgency and frequency are often caused by a simple urinary tract infection. Kidney stones can also cause these symptoms as they pass through the last part of the ureters. Irritative voiding symptoms such as urgency and frequency are also the most common symptoms of an overactive bladder. Overactive bladder is common in both older men and women.
If the tumor is located near the urethral orifice, it may block the flow of urine from the kidneys and cause an obstruction. Obstruction may often lead to back pain, nausea and vomiting especially if it occurs quickly. More gradual obstruction is often a symptomatic. Very rarely, both ureteral orifices may become obstructed, leading to low urine output and kidney failure. If the cancer has spread to an area outside of the bladder, then it could cause swelling of the legs or bone pain. Finally, if the tumor is very large it could be felt as a mass in the lower abdomen.
V. TREATMENT
Treatment of bladder cancer depends on the stage of the disease when it is first discovered. In the earliest stages of the disease, the cancer will appear as a warty growth on the internal lining of the bladder, known as a papillary carcinoma. The next main stage is reached when the cancer extends into the bladder wall to involve the muscle in this wall. Finally, the most advanced stage is when the cancer has extended beyond the bladder wall and encroaches on other organs in the pelvis. All these stages can be sub divided further by assessing the spread of the cancer to the local lymph nodes.
In the earliest stage of bladder cancer the growth can normally be removed at the initial cystoscopy by simply burning the papillary carcinoma from the bladder wall with a diathermy probe, which is introduced into the cystoscope. This procedure is often curative in itself though it will be necessary to have repeat cystoscopy examinations because the rate of recurrence of these cancers is quite high.
In addition to this surgical treatment, external or internal radiotherapy can be give. Internal radiotherapy in this case will involve introducing a radioactive compound into the bladder which irradiates all suspicious areas of the bladder lining. To radioactive solution is subsequently washed out of the bladder.
For the intermediate stages of bladder cancer the part of the bladder which contains the cancer is surgically removed. Following this radiotherapy is given either externally or internally.
In some centers chemotherapy may be given in the form of a solution directly introduced into the bladder. Repeat cystoscopies will be required to detect and treat recurrences. In the late stages of bladder cancer there is normally no alternative but to remove the bladder completely a procedure which may be followed by both radiotherapy and chemotherapy.
Bladder is the organ that stores urine after its formation by the kidneys. It consists of three layers: a lining of mucous membrane, called epithelium; a midway layer of involuntary muscle, with fibers arranged in three layers, each running in an unlike direction; and an outer layer of connective tissue, roofed by the peritoneum above and to the back and blending with the connective tissues of the body wall in front and below. Urine enters the bladder from the kidneys all the way through two ureters and is discharged through the urethra. The openings of the ureters lie in the basal part of the bladder, each about 3.8 cm from the opening of the urethra, which is located in the midline of the bladder at its lowest point. Average normal capacity of the adult bladder is about half a liter.
II. TYPES OF BLADDER CANCER
Bladder cancer is the most commonly encountered primary tumor of the urinary tract. The incidence is 6 to 8 percent of all male cancers but is lower in the female at 2 to 3 percent, while the male to female ratio is about 2.5: 1. It is predominantly a cancer of the elderly with highest incidence in the 60 to 70 year age group, median age at presentation being about 69 years. Cigarette smoking is the commonest conferring a two to six fold increased risk.
III. METHODS OF STAGING
At the time of presentation one third of cancers will have multifocal disease and one third is invasive. Initial imaging may have already diagnosed a bladder mass, however, as imaging is not sufficiently specific, in all cases the diagnosis needs to be confirmed by endoscopy and biopsy. Tissue analysis not only confirms the cell type but also the malignancy is further subgraded into well differentiated, low grade tumours, moderately differentiated tumors or badly differentiated high grade tumors. The higher grades have a much poorer prognosis and greater likelihood of recurrence. The five year survival for a patient with a grade one tumor is 80 to 95 percent, however, this falls to around 60 percent with a grade three cell type. Further information is gained from the depth of invasion shown by the biopsy sample. This allows the disease to be considered in two broad categories: superficial and invasive. The depth of invasion has a direct bearing on the five year survival rate, the rate being greater than 80 percent for patients with tumors confined to the mucosa or submucosa but between 40 and 60 percent depending on whether the muscle is breached and the perivestical fat is involved. Depth of invasion also influences the treatment options, in broad terms, patients with the superficial tumor; the tumors confined to the mucosa and the superficial muscle layer, are treated with local resection and maintained on surveillance for recurrent disease, with additional intravesical therapy as necessary. Patients with deeper invasive tumors are treated with the more radical options of bladder resection or radiotherapy. This is an oversimplification of what is, in practice, a complex clinical problem and one that is evolving all the time, however, it serves a make the point that accurate microscopic and macroscopic staging of bladder transitional cell carcinoma is central to the management of this disease.
IV. SIGNS AND SYMPTOMS
One of the most common signs of bladder cancer is blood in the urine. In the majority of cases, this includes microscopic amounts of blood that can only be picked up by the laboratory on a urine sample. Some people will have so much bleeding that it turns the urine pink or red. Obviously, gross hematuria is not normal, and because it is so alarming, it will often prompt quicker evaluation. Microscopic hematuria though is also not normal and should always be evaluated by a urologist. Even if the blood in the urine clears up on its own, it still always needs to be evaluated. The absence of pain does not mean that there is no need for concern.
Hematuria is not the only warning sign, however, depending on its location within the bladder; the tumor may interfere with the normal functioning of the bladder, which could manifest as irritative voiding symptoms. These symptoms include urinary urgency and urinary frequency. Urgency is the feeling of a sudden, compelling desire to urinate that is difficult to make go away. Frequency means going to the bathroom eight or more times per day. Urgency and frequency are often caused by a simple urinary tract infection. Kidney stones can also cause these symptoms as they pass through the last part of the ureters. Irritative voiding symptoms such as urgency and frequency are also the most common symptoms of an overactive bladder. Overactive bladder is common in both older men and women.
If the tumor is located near the urethral orifice, it may block the flow of urine from the kidneys and cause an obstruction. Obstruction may often lead to back pain, nausea and vomiting especially if it occurs quickly. More gradual obstruction is often a symptomatic. Very rarely, both ureteral orifices may become obstructed, leading to low urine output and kidney failure. If the cancer has spread to an area outside of the bladder, then it could cause swelling of the legs or bone pain. Finally, if the tumor is very large it could be felt as a mass in the lower abdomen.
V. TREATMENT
Treatment of bladder cancer depends on the stage of the disease when it is first discovered. In the earliest stages of the disease, the cancer will appear as a warty growth on the internal lining of the bladder, known as a papillary carcinoma. The next main stage is reached when the cancer extends into the bladder wall to involve the muscle in this wall. Finally, the most advanced stage is when the cancer has extended beyond the bladder wall and encroaches on other organs in the pelvis. All these stages can be sub divided further by assessing the spread of the cancer to the local lymph nodes.
In the earliest stage of bladder cancer the growth can normally be removed at the initial cystoscopy by simply burning the papillary carcinoma from the bladder wall with a diathermy probe, which is introduced into the cystoscope. This procedure is often curative in itself though it will be necessary to have repeat cystoscopy examinations because the rate of recurrence of these cancers is quite high.
In addition to this surgical treatment, external or internal radiotherapy can be give. Internal radiotherapy in this case will involve introducing a radioactive compound into the bladder which irradiates all suspicious areas of the bladder lining. To radioactive solution is subsequently washed out of the bladder.
For the intermediate stages of bladder cancer the part of the bladder which contains the cancer is surgically removed. Following this radiotherapy is given either externally or internally.
In some centers chemotherapy may be given in the form of a solution directly introduced into the bladder. Repeat cystoscopies will be required to detect and treat recurrences. In the late stages of bladder cancer there is normally no alternative but to remove the bladder completely a procedure which may be followed by both radiotherapy and chemotherapy.
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