Bladder Cancer Basics

What is 'bladder cancer'?

Bladder cancer is a malignant tumor, or a malignant growth within the bladder. Bladder cancers can be small or large. They can be low grade, intermediate grade or high grade. They can exhibit a variety of different behaviors in terms of their recurrence pattern or progression, but ultimately most, if not all, growths within the bladder are malignant and need to be attended to.

What kind of a doctor specializes in bladder cancer?

Generally, bladder cancer is treated by urologists. Within urology, there are some uro-oncologists who specialize in bladder cancer treatment, but most bladder cancer that presents is superficial, low grade, and non invasive. The bulk of the patients with bladder cancer are currently treated by their community urologist. As bladder cancer advances or progresses, urologists tend to rely and consult with medical oncologists, as well as radiation oncologists, in terms of managing patients with advanced bladder cancer. There is a multi-discipline area approach to patients who are either high risk or have advanced bladder cancer, but the bulk of the bladder cancer that is seen on a day to day basis is generally treated by the community urologist, who is trained to diagnose and treat the disease.

What causes bladder cancer?

The short answer is that we don't know. Certainly, epidemiologic and environmental data over the years has suggested a relationship between certain toxic exposures, number one being cigarette smoking. We do see patients who present with bladder cancer, where there is no clear cut history of either smoking or any exposure to any environmental carcinogens. The answer is not so clear cut, and the causes of bladder cancer, much like the causes of many other cancers, are still remaining to be defined.

How common is bladder cancer?

Bladder cancer is surprisingly common, although it's not well represented in terms of support groups or media attention. When we try to estimate how common it is, we talk about two aspects of the disease. One is the incidence, in other words, how many new patients are diagnosed with bladder cancer a year - and that's estimated to be about 70,000 in the US and about 350 to 450 thousand worldwide, although we dont have accurate reporting from central Asia and some parts of the world. What's a much more telling number, is the prevalence of bladder cancer, and that refers to the number of patients who at any one time are alive with bladder cancer, and because patients with bladder cancer tend to live a long time and not succumb to the disease, the prevalence of bladder cancer in the United States is now estimated to be about 600 000 subjects or patients. When you look at that, it is the second-most common or most prevalent cancer in the United States today.

Are there different types of bladder cancer?

The most common type of bladder cancer that we see in the United States and the Western world is transitional cell carcinoma of the urinary bladder. Transitional cell refers to the cell type that lines the urinary bladder. This type of cell lines the bladder, the ureters that drain urine from the kidney down to the bladder, and also the urethra, where urine is transported outside the bladder. The cancer that starts from these cells is therefore called transitional cell carcinoma. About 85 to nearly 90% of the bladder cancer that we see in this country is of the transitional cell variety. There are different types of cancers - squamous carcinoma is also seen. This tends to be a little bit more of an aggressive type of cancer. It tends to be associated with different risk factors, primarily chronic infection and chronic inflammation and irritation. It can be seen in this country associated with chronic catheter use or bladder stones. In other parts of the world, especially Northern Africa and Egypt up the Nile Valley, there's a strong association with a parasitic infection called Schistosomiasis or Bilharziasis, in which the parasite invades the bladder. The most common type of cancer seen in that part of the world is not transitional cell carcinoma but squamous cell carcinoma, and the treatment is quite different for that kind of tumor. In addition to these two, there are some rarer cancers - adenocarcinoma of the bladder is seen, ring cell carcinoma, and mucinous carcinoma of the bladder. There is finally a urachal carcinoma or a urachal variant, which is probably the rarest in this country. Urachal carcinoma refers to its origins in the urachus, which is the remnant of the umbilical cord connecting to the dome of the bladder.

What are the symptoms of bladder cancer?

Bladder cancer per se, generally does not have any symptoms. This is one of the reasons that it's under-diagnosed, and sometimes not diagnosed early enough. The usual presenting symptom of bladder cancer is referred to as painless hematuria. Hematuria means blood in the urine. It is painless, as opposed to other causes of blood in the urine, or hematuria, that are associated with passage of a stone, or infections where there's usually pain, discomfort, burning, or pressure symptoms. Patients with bladder cancer use the restroom as they would normally, and happen to notice that there might be some blood in the urine. Fortunately, bladder cancer tends to bleed early - it's thought to be due to the fact that it's a very vascular tumor with a lot of new blood vessels growing, and also because during urination, the bladder contracts pretty forcefully, and that filling contraction tends to promote bleeding. Most patients do tend to notice some bleeding early in the course of the disease. The downside of the fact that other than the bleeding there's no symptom with it, is that the bleeding generally is not persistent, in other words you can see some blood one day and not the other. That's one of the reasons that the diagnosis of bladder cancer, especially in women, is sometimes delayed - because the blood disappears, they assume it was nothing or just a little broken blood vessel, or maybe some menstrual bleeding interspersed with it. Since it disappears, they don't pursue it through their family physician.

What are common bladder cancer risk factors?

We certainly have a clear knowledge of some of the well defined and associated risk factors in bladder cancer. Risk factors that have been proven and identified are primarily varied. Smoking is the number one risk factor. Smoking increases your risk of developing bladder cancer throughout your lifetime four fold, so it's a significant risk. If you think about it, it makes sense - the metabolites of the tar and the nicotine that are inhaled get into the blood stream and are filtered by the kidney. The kidney then secretes these toxic waste products into the urine and they're stored in the bladder. Although you urinate anywhere from six to eight, to ten times a day, in between urination these products, these toxic carcinogens sit in the bladder, and irritate the lining, and subsequently lead to bladder cancer. Similar, men and women who have worked in rubber industries - annelyn dyes that were used, especially around the turn of the previous century in the leather industry were at high risk, and there are a number of Napthol related chemical industries, some pesticide industries where there's a risk to the workers themselves.

Is bladder cancer inherited?

There is no strong evidence to support any type of genetic link. There have been some studies that have looked at familial bladder cancer, but even in families where there appears to be an increase in incidents, there are several generational skips. What we can say today is that there is no conclusive evidence to suggest any genetic link or familial link or inherited link to bladder cancer.

What is 'urachal cancer'?

Urachal Carcinoma refers to a malignancy that starts from the Urachal remnant. The urachus is the remnant of the umbilical cord. During fetal development, the dome of the bladder is connected through the belly button, through the urachus, and after fetal development that tissue becomes fibrotic and generally disappears, although urachal remnants are seen with some frequency during abdominal surgery. Rarely, however, a malignant tumor can develop from this, and since it is attached to the dome of the bladder, it can present as a bladder cancer. Unlike the other variants of bladder cancer that tend to start in the lining cells of the bladder, this starts within the wall of the bladder and then pushes out towards the lining. It is a rare cancer, but it's presentation is quite different.

What kind of bladder cancer presents with the symptom of frequent urination?

Most bladder cancers are asymptomatic, in that they do not cause any burning, pressure, discomfort, or frequency. However, Carcinoma in Situ was initially thought to be an early form of bladder cancer, but is actually a more aggressive form of bladder cancer. Transitional Carcinoma can present with what are called irritative bladder symptoms of frequency, urgency, and again these are often treated or assumed to be symptoms of an infection, and often are treated with one or two or several courses of antibiotics before proper investigation is done, and the proper diagnosis is made.

Is the mortality rate high for people with bladder cancer?

The mortality rate for bladder cancer depends on the stage and grade at the time of the initial diagnosis. Fortunately, most patients who present with blood in the urine and are subsequently diagnosed to have bladder cancer have low grade superficial bladder cancer. It's estimated that for patients who are newly diagnosed with bladder cancer, sixty to seventy-five percent of those patients have low grade tumors. Again, they're still malignant tumors, but they tend to have low propensity to infiltrate the bladder, to spread to other parts of the body. The prognosis for those patients is actually quite good. The likelihood of living five years with superficial bladder cancer is about ninety five percent. The recurrence rate at five years is quite high. It's around sixty percent, but most of those recurrences also tend to be low grade and superficial. The outcome for patients who present with high grade or invasive bladder cancer is different. Those patients have an overall five year life expectancy of just under fifty percent, forty five to forty eight percent range, even with the best of care.

Why is bladder cancer so deadly?

A bladder cancer, generally, is not as deadly as many of the other cancers. It is the fourth leading killer for men, and the eighth leading killer for women, but that, in men, is behind lung cancer, it's behind colorectal cancer, and it's behind prostate cancer. Part of the reason that the numbers are so large is because so many patients actually have it, and they live a long time before succumbing to it. The patients who die of bladder cancer are generally patients who present with more aggressive forms of bladder cancer, either higher grade or higher stage, or a combination; patients who have ignored their symptoms for a long time and present too late for any type of curative procedure. In general, great strides are being done, and the concept of screening for bladder cancer is being introduced with newer, at-home screening tests under development, although there's no current recommendation, or availablity - but that's the direction that we're headed. We will impact the mortality associated with bladder cancer within our lifetimes.