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New Treatments for Bladder Cancer

There are over 50,000 new cases of bladder cancer diagnosed per year. There is a 2:1 to 3:1 ratio of men to women with this disease. Part of this is explained on the basis of different rates of smoking in men versus women. The other reasons are not well understood. The mortality rate for bladder cancer has increased.

The etiology of bladder cancer is not well understood. Like most other malignancies, it is an environmental cancer. About 50% of bladder cancers can be accounted for on the basis of cigarette smoking. There is a dose-response relationship between the amount of cigarettes.

The typical presentation for bladder cancer is painless hematuria, generally it is gross hematuria. Sometimes microscopic hematuria. Rarely do we see irritative symptoms. Usually this occurs in the context of extensive carcinoma in situ, which we’ll come back to. If bladder cancer is suspected, based on hematuria - gross hematuria or microscopic hematuria or irritative symptoms - there is some imaging that takes place.

The staging of bladder cancer is strictly on the basis of the depth of invasion of the tumor into the bladder wall. There are two subsets of bladder cancer. One is superficial bladder cancer and the other is bladder cancer, which is seen by medical oncologists in the context of multi-modality therapy. Superficial bladder cancer consists of three different subtypes; carcinoma in situ, which is generally a high-grade potentially very aggressive tumor that involves just the superficial epithelial layer of the bladder.

Superficial bladder cancer has a tendency to recur. Over 50% of the time after initial presentation it will recur. Rarely, superficial bladder cancer will progress onto invasive or metastatic disease. The likelihood of progression to metastatic disease can be predicted to a certain extent based on the T-stage of the tumor and the grade of the tumor.

Superficial bladder cancer is initially treated with resection of the primary. After resection, one needs to see some muscle in the biopsy to say, "No, there is no muscle involvement. Therefore, it is superficial bladder cancer." So resection is the primary therapy. Intravesical chemotherapy is used for recurrent or multi-focal superficial bladder cancer. Thus far it has been proven to reduce the likelihood of recurrence, reduce the frequency of the number of tumors that recur.

For muscle invasive disease, the prognosis is largely dependent upon the depth of invasion, the T-stage of the tumor, to a lesser extent tumor grade. Because the majority of muscle invasive tumors are high grade. The treatment of choice for invasive bladder cancer in the United States is a cystectomy.

There have been efforts to try to reduce the likelihood of microscopic metastatic disease at the time of local therapy. Neoadjuvant chemotherapy had been very popular for many years, where chemotherapy is given prior to cystectomy or prior to radiation. Chemotherapy will frequently reduce the size of the tumor in patients with bulky locally advanced tumors and make the tumor more operable. However, there are no randomized studies yet that have been performed that have demonstrated a survival benefit to giving neoadjuvant therapy.

Adjuvant chemotherapy. The standard chemotherapy in the United States, MVAC four-drug regimen - methotrexate, vinblastine, Adriamycin, cisplatin - or CMV which is cisplatin, methotrexate and vinblastine. There are no studies yet involving the newer drugs, Taxol.