Bladder Cancer Treatment
Is there a cure for bladder cancer?
We do not have a cure for bladder cancer today. What we do have, in bladder cancer, is excellent diagnostic tests, and easy to administer treatments. For patients who follow their treating physicians recommendations, maintain their follow-up schedules, and comply with the recommendations, the good news is that most patients will survive bladder cancer. In fact, for most patients who present with superficial low-grade bladder cancer, and that's around 80% of all patients who present with bladder cancer, the five-year survival bid is about 94 to 95%. Thus, the risk of death with bladder cancer is relatively low.
What kinds of treatments are available for bladder cancer?
The treatment for bladder cancer needs to be individualized, and it's individualized based on a number of factors. There are guidelines for stage and grade, or locally advanced versus widely medistatic tumor, superficial tumor versus invasive tumor. In addition to the stage and grade of the tumor, obviously the patients health, overall condition, and life expectancy play a role. We're going to treat somebody who's 35 with an agressive bladder cancer quite differently than somebody whos 85 or 88 years old, because their physiology is different. They're able to withstand and recover from different sorts of therapy. The mainstay of the treatment of bladder cancer is surgical removal - removing any obvious or visible growths, and then, following surgery, very careful surveillance on an every three to four month basis for a pre-set number of years. Patients who present with high-grade or higher risk category, in addition to surgery, have to have some sort of medication instilled into the bladder on a regularly scheduled basis, maintain that maintenance therapy on a fixed schedule, and are monitored very closely. That's the mainstay for most patients. Patients who present with a more aggressive disease or a more invasive disease, have to consider more radical surgical options, such as removal of the bladder and diversion of the urinary stream.
How will I know which treatment options are best for my bladder cancer?
The key is communication. It takes great communication between the patient, the patients family, and the treating physician, as well as utilising some of the resources that are available today, especially on the internet - support groups, chat rooms, or blogs. There is a tremendous amount of information out there, but the old story that a little information can be a dangerous thing is also true. Communication between the patient and the patient's treating physician is utmost, and in most instances the doctor (the treating physician) will give you the diagnosis based on his experience, and the guidelines that are out there, and will give you what he or she feels is best for your individualised care. Given the wealth of information out there, we talk about second opinions a lot, and more information is better than less information. Certainly, second opinions are appropriate - especially if one is facing a much more invasive procedure, a more radical surgical procedure.
Are there any new therapies on the horizon for bladder cancer?
Something that is now being employed more and more frequently, is called the orthotopic neobladder. Neobladder means new bladder, orthotopic means in the same place, so it's a new bladder created in the same place as the old bladder. What is done is that same small bowel reservoir, instead of coming out to the side of the abdomen, is now turned and hooked back to the urethra remnant; both in men and women. It is a little bit more commonly used in men than it is in women - it's technically a little bit more difficult in women, but that's the direction that we're going.
What's the chance for recurrence of bladder cancer?
Recurrence of bladder cancer is high across the board for patients who present with superficial bladder cancer. The expected recurrence rate at five years is 60 to 70 per cent. That's why we stress upon patients that although the tumors may be small, they may be low-grade, they may be non-invasive, but we know that they're going to recur. We try to instill upon them the need for careful, conscientious, well planned, follow up examinations.
What is 'biological therapy'?
Biologic therapy in bladder cancer refers to the installation or the administration of biologic agents into the bladder. In the case of bladder cancer, what we generally refer to is BCG. BCG is bacillus calmette guerin, which is the bacillus, or the germ, that causes tuberculosis. The germ itself is attenuated, meaning that it is treated and it's weakened. The idea behind that is that it's weakened where, although the organism itself is still live, a live organism is being instilled. It is weakened where it will not cause an infection, but will be picked up by the cells, or will enter the cells. Due to the nature of the organism, it will cause an intense inflammatory response locally within the tumor, and systemically within the host. The body will recognize this, the immune system will recognize this, and generate antibodies and lymphocytes to fight it off. Today, BCG is the number one chemotherapy or intravesical therapy for patients with either intermediate or high risk bladder cancer.
How is biological therapy used to cure bladder cancer?
Biologic therapy is used to treat bladder cancer and hopefully to cure it, and it works very well. The biologic therapy for bladder cancer is the installation into the bladder of an organism that is referred to as BCG. It's actually the germ or the organism that causes active tuberculosis. The active tuberculose organism is attenuated - it is weakened by a heat type treatment to the point where the organism, although it is live, will not cause an infection within the host (within the patient) where it is administered. What it is able to do, is to stimulate the immune system of the host or the patient two ways. One is to cause an intense inflammatory response within the bladder where it's administered, especially within the tumor. Also, it stimulates, essentially turns on, the immune system of the host . The host recognizes that this is a foreign substance, it's a tuberculose organism, and wants to fight it off by generating lymphocytes and other antibodies to fight. BCG works very well - it's relatively easy to administer, it's relatively inexpensive, and it's the mainstay in addition to surgery for patients with intermediate and high-risk bladder cancer today.
Is there a new treatment for bladder cancer on the horizon?
There are several new treatments investigated for recurrent bladder cancer on the horizon. Most of them are focused on intravesical therapy. One of the new treatments is a drug called EOquin, which we are developing here at Spectrum Pharmaceuticals. EOquin is a new type of a chemotherapeutic drug. It is called an alcolating agent because it interferes with the DNA make-up of the cancer cell. It is related, or an analog, to a chemotherapeutic drug that's been around for some time called Mytomycin, but EOquin is unique in several aspects. One is that it is referred to as a pro-drug. It is itself not very active, but has to be in an environment where it is, essentially, activated by the body. Ideally, EOquin is activated in an environment where there is little to no oxygen, hence the bladder is a perfect place for it because it is instilled into the bladder, and it takes a certain type of enzyme, which is found more frequently in transitional cell carcinoma, or bladder cancer cells. EOquin instilled into the bladder becomes a chemotherapeutic drug. What's also unique about EOquin is that the molecule itself is quite large. Where this has a role, is that large molecules are not absorbed through the lining of the bladder very easily. In fact, we've just completed a pilot study and reported on a study where patients were instilled EOquin directly into the bladder. EOquin was retained for an hour, right after surgery, so that the area in the bladder where the tumor was resected was still raw. These patients then had blood levels drawn systematically at set time points, immediately after the installation, to see if we could detect any EOquin in their circulating blood stream. In none of the patients was either EOquin or any of its metabolites detected. What this means is that in terms of a chemotherapy drug, most of the side effects of chemotherapy drugs that you hear of, or that most patients associate - such as nausea, vomiting, hair loss, fatigue and tiredness - are due to the fact that it's within their circulation. It reaches other tissues within the body. With EOquin, that should not be a problem.
How will EOquin work?
EOquin is an interesting drug. It is an analog of a chemotherapy drug called Mitomyacin C, that has been around for many years. What seems to be unique about EOquin is that it is often referred to as a pro-drug. EOquin, by itself, is not active. There are certain enzymes that are found in primarily bladder cancer, which activate the drug in an environment that's oxygen-free. The bladder is an ideal target for it, because it's oxygen-free, and bladder cancer elicits the particular enzyme that activates the drug. What's also interesting about EOquin is that when you look at the chemical structure of it, it's a large structure, and by virtue of the fact that it's a large structure, it's not absorbed through the bladder. We've completed and reported on a study here at Spectrum that has looked at immediate post-operative installation of EOquin that was retained for an hour and, during that time point, and after, blood levels were drawn in 20 subjects, looking to see if there was any detectable EOquin in the blood stream, and neither EOquin nor any of its metabolized were detected. Although EOquin is a chemotherapeutic agent, since it doesn't get into the systemic circulation, you will not get the nausea, vomiting, hair-loss and similar symptoms that most patients associate with chemotherapy.