What is Bladder Cancer?

Overview

Bladder cancer is one of the most common cancers of the urinary system in India. According to the Indian Council of Medical Research (ICMR), bladder cancer ranks among the top 10 cancers in men, with an estimated 12,000–15,000 new cases diagnosed annually. It is more common in men than women and usually affects people over the age of 55^(1,3).

What is Bladder Cancer?

Bladder cancer is the abnormal, uncontrolled growth of cells that form a tumour in the urinary bladder, the organ that stores urine before it is excreted from the body. Most bladder cancers start in the urothelial cells (also known as transitional cells) that line the inside of the bladder. Over time, these cells may become cancerous and grow into the bladder wall or spread to other parts of the body^(2,3).

Types of Bladder Cancer (3,4,5)

Bladder cancers are classified based on the type of cells involved:

• Urothelial carcinoma (Transitional Cell Carcinoma): The most common type, accounting for over 90% of bladder cancers.
• Squamous Cell Carcinoma: Linked to chronic infection or irritation of the bladder.
• Adenocarcinoma: A rare type, developing from glandular (mucus-secreting) cells in the bladder lining.

Stages of Bladder Cancer

According to the American Joint Committee on Cancer (AJCC), the AJCC TNM system (8th Edition) is a widely used staging system for bladder cancer. It combines information about the tumour (T), the extent of spread to nearby lymph nodes (N), and whether the cancer has spread to distant organs (M), to determine the overall stage of the disease². Numbers or letters after T, N, and M provide more details about each of these factors, with higher numbers generally indicating more advanced disease.

Once the T, N, and M categories have been determined, they are combined in a process called ‘staging’ to arrive at an overall stage group. These stages are described by Roman numerals from Stage I to Stage IV, and may sometimes be divided further (e.g., Stage IIIA, Stage IIIB)⁵.

The grade (G) of the tumour: which describes how abnormal the cancer cells appear under the microscope is also reported separately, as it helps guide prognosis and treatment decisions^(4,5).

Bladder cancer is broadly staged as follows^(2,4,5):

• Stage 0: Cancer cells are limited to the inner lining of the bladder.
• Stage I: Cancer has grown into the connective tissue but not the muscle layer.
• Stage II: Cancer has invaded the bladder’s muscle wall.
• Stage III: Cancer has spread through the bladder wall to nearby tissues or organs.
• Stage IV: Cancer has spread to lymph nodes or distant organs (metastatic bladder cancer).

Other systems such as the WHO/ISUP grading system and EORTC risk models are also used to assess tumour grade and risk of recurrence, especially in non-muscle invasive bladder cancers.

Causes of Bladder Cancer (2,3,4)

The exact cause of bladder cancer is not always known. However, certain risk factors increase the likelihood of developing it:

• Tobacco smoking: The leading cause, responsible for more than 50% of cases in men and 30% in women.
• Occupational exposure: Long-term exposure to industrial chemicals used in dyes, paints, rubber, and leather industries.
• Chronic bladder irritation: From repeated urinary infections, bladder stones, or long-term catheter use.
• Radiation therapy: To the pelvis for other cancers.
• Certain medications: Such as cyclophosphamide or pioglitazone.
• Family history: A family member with bladder cancer can slightly increase risk.

Like most cancers, bladder cancer develops when genetic mutations cause cells to grow and divide uncontrollably, forming a tumour.

Symptoms of Bladder Cancer (3,4)

Symptoms can vary, but the most common early sign is blood in urine (hematuria), which is often painless and may come and go. Other symptoms include:

• Frequent or urgent need to urinate.
• Pain or burning sensation during urination.
• Lower abdominal or back pain.
• Difficulty urinating or weak urine flow.
• Fatigue and unexplained weight loss in advanced cases.

Screening and Diagnosis

There is no routine screening test recommended for bladder cancer in the general population^2,3.

Diagnosis begins with a detailed medical history and physical examination, followed by:

• Urine cytology: Examination of urine for abnormal cells.
• Cystoscopy: A thin tube with a camera is inserted through the urethra to view the bladder lining.
• Imaging tests: CT scan, MRI, or ultrasound to assess the tumour’s size and spread.
• Biopsy: Tissue sampling during cystoscopy confirms the diagnosis and type of cancer.

Treatment of Bladder Cancer (2,3,5)

Once diagnosed, a multidisciplinary cancer care team including Uro-Oncologists, Medical Oncologists, and Radiation Oncologists will discuss the best treatment options based on the stage and grade of the cancer.

1. Surgery
   • TURBT (Transurethral Resection of Bladder Tumour): For early-stage or non-muscle invasive cancers.
   • Partial or Radical Cystectomy: Removal of part or all of the bladder, with urinary reconstruction in advanced stages.
2. Intravesical Therapy

   Involves placing medication directly into the bladder (e.g., BCG therapy or chemotherapy drugs such as mitomycin C) to kill residual cancer cells and prevent recurrence.

3. Chemotherapy

   Systemic drugs like Cisplatin, Gemcitabine, and Methotrexate are given intravenously before or after surgery, or in advanced disease.

4. Radiation Therapy

   Used when surgery is not possible or as part of a bladder preservation approach. Techniques include IMRT (Intensity Modulated Radiation Therapy) and IGRT (Image-Guided Radiation Therapy).

5. Immunotherapy and Targeted Therapy

   Immune checkpoint inhibitors such as Pembrolizumab, Nivolumab, and Atezolizumab help the body’s immune system recognize and destroy cancer cells.

   Targeted therapies (e.g., Erdafitinib) are used in certain advanced bladder cancers with specific gene mutations.

Survival Rate (2,3,4)

The survival rate depends on the stage, grade, and overall health of the patient.

• Early-stage bladder cancers (confined to the bladder lining) have a high 5-year survival rate of about 85–90%.
• Muscle-invasive bladder cancers have lower survival rates (approximately 40–60%).
• Advanced or metastatic cancers require combination therapy and ongoing monitoring⁵.

Regular follow-up is important, as bladder cancer has a tendency to recur even after successful treatment.

References

1. Indian Council of Medical Research (ICMR) – National Cancer Registry Programme (NCRP), 2023
2. National Cancer Institute (NCI), USA – Bladder Cancer Treatment (PDQ®)
3. American Cancer Society (ACS) – Bladder Cancer: Causes, Symptoms, and Treatment (2024 update)
4. Cancer Research UK – Types and Stages of Bladder Cancer
5. National Comprehensive Cancer Network (NCCN) Guidelines – Bladder Cancer (Version 2025.1)