Invasive bladder cancer is a form of the disease in which cancer cells move past the lining of the bladder to the surrounding muscles, and perhaps to other organs and through lymph fluid. This type of cancer is more likely to develop if it begins to grow in the transitional cells, which line the wall of the bladder. The condition is less common than superficial bladder cancer, which only affects the bladder lining.
There are three primary kinds of cells that can present themselves in bladder cancer: adenocarcinoma, squamous cell carcinoma, and urothelial or transitional cell carcinoma. The previous two types are more likely to develop into invasive bladder cancer, while transitional cell carcinoma usually only presents itself as superficial bladder cancer. Adenocarcinoma typically originates in the glands. Squamous cell carcinoma tends to grow as the result of long-term inflammation and irritation in the bladder.
Each form of bladder cancer is given a classification based on its level of penetration into the body. Invasive bladder cancer is one of the highest possible classifications of the disease. Squamous cell carcinoma and adenocarcinoma tend to be more aggressive because they have usually developed for a long time before they are discovered.
Bladder cancer is also diagnosed based on the grade or size of the tumors. Most superficial bladder cancers typically consist of low-grade tumors. High-grade tumors, on the other hand, are common in invasive bladder cancer. Medical professionals may also be able to determine by tumor type what the chances are that the cancer will return after it is treated.
Most cases of invasive bladder cancer are treated via radical cystectomy, which is a surgical procedure that removes the bladder. This surgery is primarily undertaken due to a high risk of recurrence of the disease, which can often be worse or fatal if it develops a second time. Other problematic growths are typically also removed during this procedure, in a process called pelvic lymph node dissection. Though the disease is aggressive, some doctors will attempt to find a means of saving the patient’s bladder before resorting to surgery.
Other options for treating invasive bladder cancer include the generally discouraged practice of preserving the bladder and performing a partial cystectomy. To save the bladder, most patients will undergo radiation treatments that shrink the tumors. In most cases, chemotherapy is believed to be too toxic for the bladder. Partial cystectomy is a newer and rarely used procedure. It involves the removal of lymph nodes and tumors and may also be followed by radiation.