Symptoms, Diagnosis, and Treatment Process of Bladder Cancer

Bladder cancer is the second most common cancer occurring along the urinary tract, starting from the kidneys. Approximately two-thirds of bladder cancers are non-fatal but tend to recur, while one-third have the potential to invade muscle tissue and subsequently metastasize to the rest of the body, exhibiting a more aggressive course.

The kidneys filter and cleanse approximately 200 liters of blood per day. Following this process, the kidneys produce about 1.5 liters of urine daily to maintain internal fluid balance and ensure the purification of the blood. The kidneys transport waste substances, which need to be eliminated from the body, to the bladder through the urinary tract within the produced urine.

The primary function of the bladder is to store urine. The operation of the bladder is controlled by the central nervous system. When the urine stored in the bladder reaches a certain level, the urge to urinate arises.

What is Bladder Cancer?

Bladder cancer is the second most common cancer occurring along the urinary tract, starting from the kidneys. Approximately two-thirds of bladder cancers are non-fatal but tend to recur, while one-third have the potential to invade muscle tissue and subsequently metastasize to the rest of the body, exhibiting a more aggressive course.

Bladder cancer occurs more frequently in men than in women and typically develops in adults. In Turkey, bladder cancer ranks third most common in men and thirteenth in women among the most common cancers.

What Are the Symptoms of Bladder Cancer?

After bladder cancer develops, the most important symptom prompting patients to seek medical advice is painless urination with visible reddish discoloration due to the presence of red blood cells in the urine. This symptom is known as macroscopic hematuria.

In addition to blood in the urine, several other symptoms may occur during the course of the disease:

• Pain in the groin and above the groin
• Frequent urination
• Urgency to urinate
• Presence of blood in the urine detectable by a microscope (microscopic hematuria)
• Presence of blood clots in the urine
• Painful urination
• Feeling of a mass and fullness in the groin area
• Back pain
• Fatigue
• Weight loss

If the disease spreads to other tissues and organs (metastasis), it can cause various symptoms depending on the affected area. For example, symptoms such as coughing or coughing up blood may indicate that bladder cancer has spread to the lungs. The appearance of bone pain in bladder cancer patients may suggest that the disease has spread to the skeletal system.

What Are the Stages of Bladder Cancer?

The staging of bladder cancer utilizes a system called the TNM classification.

• T: Evaluates the presence and spread of bladder cancer. T1 tumors are in more superficial parts of the bladder, T2 tumors invade muscle tissues, T3 tumors spread to the fatty tissue surrounding the bladder, and T4 tumors indicate the spread to other organs.
• N: Classifies whether bladder cancer has spread to the lymph nodes. Involvement of a single lymph node smaller than 2 centimeters is called N1, involvement of multiple lymph nodes between 2-5 centimeters is called N2, and involvement of any number of lymph nodes larger than 5 centimeters is called N3.
• M: Evaluates whether the cancer has spread to organs outside the bladder. If metastasis is detected, it is classified as M1; if not, it is classified as M0.

The clinical staging of bladder cancer, derived from the TNM classification, is divided into 4 stages:

• Stage 1: Superficial cancer of the bladder without lymph node involvement or spread to other organs.
• Stage 2: Cancer has advanced into deeper muscle tissues without spread to other tissues and organs.
• Stage 3: More advanced clinical stage typically involving lymph node involvement without distant organ spread.
• Stage 4: Indicates that the disease has spread to distant tissues and organs.

How Does Bladder Cancer Develop?

Cells that make up the human body have a specific life cycle. During their life cycle, cells grow, develop, and eventually age. Aged cells sacrifice themselves to make way for new cells, maintaining a delicate balance.

When this cycle is disrupted due to various factors, and a cell starts to multiply and spread uncontrollably, it is defined as cancer. Cancers are usually named according to the tissue and organ from which they originate.

What Causes Bladder Cancer?

Many risk factors can cause the development of bladder cancer. The most commonly identified are chemical substances, along with various infections and medications, which are considered risk factors.

• Genetic mutations
• Smoking
• Various occupations such as paint industry, dry cleaning, rubber, and chemical industries
• Schistosomiasis, a parasitic disease that settles in the bladder
• Irritation caused by bladder stones over long periods
• Certain painkillers and cancer medications

Diagnosis of Bladder Cancer

Urology specialists use various imaging methods, laboratory tests, evaluation of cells excreted in the urine, and microscopic examination of biopsy samples to diagnose bladder cancer.

• Biochemical laboratory tests: Urine tests, blood values, kidney and liver function tests, and other assessments can be conducted in bladder cancer patients.
• Urine cytology: Involves the microscopic examination of normal or cancerous cells from the bladder excreted in the urine.
• Imaging tools: Ultrasound, intravenous urography, computed tomography, magnetic resonance imaging, and cystoscopy can be used in the diagnosis of bladder cancer.

Computed tomography and magnetic resonance imaging can determine whether the disease has spread outside the bladder.

Bone scintigraphy can be used to evaluate the spread to the skeletal system in bladder cancer patients who complain of bone pain.

Cystoscopy allows for endoscopic evaluation of the bladder. During the cystoscopy examination, a method called transurethral resection (TUR) can be applied to take a sample. TUR can be used for both diagnosis and treatment.

Treatment of Bladder Cancer

Different methods are used in the treatment planning of bladder cancer based on whether the disease has spread to muscle tissue. If there is no muscle invasion, intravesical BCG therapy can be applied following the endoscopic removal of the lesion.

BCG therapy can provide a gain of about 40% in terms of recurrence and progression prevention. Side effects such as muscle fatigue, weakness, nausea-vomiting, diarrhea, fever, and pain during urination can occur after this procedure.

Surgical procedures applied in bladder cancer can involve complete or partial removal of the bladder, depending on the tumor stage and localization. In bladder cancers that have spread to muscle tissue, a surgical approach called radical cystectomy is usually applied. Chemotherapy can be used as an additional treatment approach to surgery, involving the removal of surrounding tissues and lymph nodes along with the bladder.

The treatment method aiming to destroy cancer cells using high-energy rays is called radiation therapy. Radiotherapy applications are particularly prominent in patient groups where surgical interventions are not suitable or preferred.

Bladder-sparing treatment approaches involve reducing the cancerous structure as much as possible with transurethral resection (TUR), followed by a combination of chemotherapy and radiotherapy, instead of complete removal of the bladder. Such organ-sparing approaches can be considered in suitable patient groups following the physician's evaluation.

If bladder cancer has spread to other parts of the body, systemic chemotherapy and/or targeted therapy (targeted immunotherapy) come to the forefront as treatment options.