Bladder Cancer
Bladder cancer occurs when the cells that make up the urinary bladder – starting with those that line the organ – begin to grow uncontrollably. As more cancer cells develop, they can form a tumor and, if not treated early, spread to other parts of the body.
It is one of the most common tumors of the urinary tract and the ninth most incident type worldwide. When compared by gender, it ranks sixth in men and 19th in women. The estimated risk of a person having bladder cancer is 7.23 new cases per 100,000 men and 2.8 per 100,000 women.
Types of bladder cancer
Bladder cancer is classified according to the type of cell that has undergone changes. There are three types:
- Transitional cell carcinoma: represents the majority of cases and begins in the cells of the innermost tissue of the bladder;
- Squamous cell carcinoma: affects the thin, flat cells that can arise in the bladder after prolonged infection or irritation; and
- Adenocarcinoma: begins in the glandular (secretory) cells that can form in the bladder after long-term irritation or inflammation.
Bladder cancer is considered superficial when it is limited to the lining tissue of the bladder, and invasive when it spreads through the lining of the bladder and invades the muscular wall. It can affect nearby organs or lymph nodes.
Symptoms of bladder cancer
Blood in the urine is considered the main symptom of bladder cancer. The amount of blood may not always be enough to change the color of the urine, but laboratory tests can detect small amounts of blood present. Early cases of the disease usually cause little bleeding and little pain, or none at all.
It is important to note that other conditions such as infections and kidney stones can also result in blood in the urine, which is why a more detailed examination is necessary to determine the causes;
In addition to blood in the urine, other symptoms of bladder cancer may include:
- Changes in urinary habits – such as urinating more frequently than usual;
- Feeling pain or burning when urinating;
- Urgency to urinate; and
- Trouble urinating or weak urine flow.
Diagnosis of bladder cancer
The diagnosis of bladder cancer can be made through urine tests and imaging exams, such as computed tomography and cystoscopy (internal examination of the bladder using a camera-equipped instrument). During cystoscopy, material can be removed for biopsy.
The likelihood of cure will depend on the staging (extent) of the cancer (superficial or invasive) and the patient’s age and overall health.
Treatment for bladder cancer
Surgery, alone or combined with other treatments, is the most common approach.
In early stages, tumors can be removed. The issue is that, over time, new cancers may form in other parts of the bladder.
There’s also the option of total bladder removal or the combined use of surgery with other approaches. Treatment options will depend on the stage of the disease.
In summary, the possible surgeries are:
- Transurethral resection: a surgery in which the doctor removes the tumor through the urethra;
- Partial cystectomy: a surgical procedure that removes only a part of the bladder; and
- Radical cystectomy: the complete removal of the bladder, with the construction of a new organ to store urine.
Radiation therapy can be used alone or in combination with chemotherapy, and sometimes it is used after surgery or as a substitute for surgery.
Regarding chemotherapy, which can be neoadjuvant (performed before surgery) or adjuvant (performed after the surgical process), there are two alternatives:
- In the systemic form, it is ingested as a medication or injected into the vein; and
- In the intravesical form, it is applied directly to the bladder through a tube inserted through the urethra.
For muscle-invasive tumors, the treatments can be as follows:
- Radical cystectomy – is the standard treatment for localized muscle-invasive tumors. The patient’s clinical condition and the presence of comorbidities are evaluated to determine the treatment. The overall five-year survival rate is around 65%, and at 10 years, around 45%; and
- Lymphadenectomy – is the removal of part of the lymph nodes and should always be performed, as it is associated with better oncological outcomes.
Prevention for bladder cancer
Avoiding risk factors is a way to prevent bladder cancer.
Smoking, among the most important risk factors for developing bladder cancer, is present in 50% to 70% of cases, and smokers have three times the risk of developing the disease compared to non-smokers.
Secondly, occupational exposure to chemicals such as aromatic amines (such as benzidine and beta-naphthylamine, used in the dye industry) accounts for about 10% of cases. Professionals at higher risk of developing bladder cancer include painters, mechanics, typesetters, hairdressers, and truck drivers (due to diesel fumes).
The use of the diabetes medication pioglitazone is associated with an increased risk of bladder cancer. Some dietary supplements containing aristolochic acid also elevate the risk of developing the tumor.
Some risk factors, however, cannot be controlled, such as:
- Race and ethnicity – whites are twice as likely to develop bladder cancer (the reasons for this difference are still unknown);
- Age – about 90% of bladder cancer patients are over 55 years old;
- Chronic irritation and infections: kidney or bladder stones and recurrent urinary tract infections have been associated with bladder cancer; and
- Family history: those who have or have had family members with bladder cancer have an increased risk of the disease.
It is important to clarify that having one or some of the risk factors, controllable or not, does not mean that the person will necessarily have bladder cancer.
