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Bladder Cancer

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Overview

In developed countries, 90% of bladder cancers are urothelial (also known as transitional cell) carcinomas. The majority are superficial (they do not invade the muscle) at presentation.

In developing countries, Schistosomiasis infection can lead to chronic inflammation of the bladder which increases the risk of squamous cell carcinoma. This can make up to 80% of cases in endemic areas.

Bladder cancer usually metastasises to the lymph nodes, lungs, liver, bone, and central nervous system.

Epidemiology

  • Around 10,000 new bladder cancers are diagnosed yearly
  • It is more common in people >65 years old
  • Around ¾ of new cases are seen in men, but both sexes can be affected

Risk Factors

Many risk factors for urothelial (transitional cell) bladder cancer are associated with exposure to aromatic organic compounds (compounds containing a benzene ring), many of which are renally excreted:

  • Smoking – around 50%
    • Tobacco smoke contains aromatic amines
    • Smoking increases the risk of bladder cancer up to 6 times
  • Occupational exposure to aromatic compounds and dyes – around 10% of cases:
    • Examples include aniline dyes in the solvents and the printing industry, textile and rubber manufacturing
  • Cyclophosphamide:
    • This is toxic to the bladder and causes bladder damage

Risk factors for squamous cell carcinoma include:

  • Schistosomiasis – more common in developing countries:
    • Likely due to chronic inflammation of the bladder
  • Smoking

Presentation

Overview

Painless haematuria is a urological malignancy until proven otherwise:

  • The hallmark feature of bladder cancer is painless gross haematuria (up to 85%). 
  • Non-visible (microscopic) haematuria can still suggest bladder cancer:
    • This may be found incidentally while testing for other conditions and can suggest bladder cancer if it cannot be explained by other causes such as a urinary tract infection (UTI)

In early stages, other features such as physical exam abnormalities or other urinary symptoms (e.g. voiding symptoms) are not present. These usually emerge in advanced disease.

Referral

Overview

Urgently refer using a suspected cancer pathway (for an appointment within 2 weeks) for bladder cancer if any of the following apply:

  • ≥40 and have any one of the following:
    • Unexplained visible haematuria without UTI
    • Visible haematuria that persists/recurs after successfully treating UTI
  • ≥60 and have unexplained non-visible haematuria and any one of the following:

Consider a non-urgent referral for bladder cancer for people ≥60 with any of the following:

  • Recurrent UTI
  • Persistent unexplained UTI

Investigations

Diagnosis

Most cases of bladder cancer are diagnosed with cystoscopy and biopsy in secondary care.

Many places have haematuria clinics that perform ultrasound scans before cystoscopy as bladder cancer shares features with other urological cancers such as renal cell cancer. 

In secondary care, the following investigations may be performed:

  • Cystoscopy – key in diagnosis:
    • Allows direct visualisation of the bladder and biopsy of suspicious lesions
  • Urinalysis:
    • To exclude infection
    • Red cells are present, white cells may be seen and may lead to confusion with UTI
  • Urine cytology:
    • May identify malignant cells, but cannot exclude a diagnosis of bladder cancer
  • CT/MRI abdomen and pelvis:
    • Screens for other causes such as renal stones and may identify bladder cancer and metastases
    • Often performed before transurethral resection of bladder tumour (TURBT)
  • Transurethral resection of bladder tumour (TURBT):
    • May be used to take a biopsy or remove bladder cancer in early stages

Staging

There are many different staging systems for bladder cancer. A modified version of the tumour, node, and metastasis (TNM) system has been made by NICE which includes histological findings. Investigations that may be used for staging include:

  • CT/MRI staging
  • CT urography
  • CT thorax
  • Fluorodeoxyglucose positron emission tomography (FDG PET)‑CT

Management

Overview

Management depends on the staging and risk category of the patient and is coordinated by a multidisciplinary team. Some management steps include:

  • Transurethral resection of bladder tumour (TURBT):
    • Tumours limited to the superficial muscle layer may be managed with TURBT alone
  • Intravesical chemotherapy:
    • Often given alongside TURBT to reduce the risk of recurrence
  • Intravesical Bacillus Calmette-Guérin (BCG) immunotherapy:
    • The BCG vaccine was initially developed for Mycobacterium bovis, which no longer infects humans. Studies have shown that bladder cancer cells take up M. bovis leading to inflammation and destruction.
    • As a result, giving the BCG vaccine is thought to trigger an immune response leading to the destruction of bladder cancer cells and has been demonstrated to be effective.
  • Radical cystectomy:
    • This involves removal of the entire bladder 

Prognosis

  • Superficial transitional cell carcinoma has a high recurrence rate (70% within 5 years) but has a good prognosis of up to 90% survival rates
  • Muscle-invasive cancer has 5-year rates of 30-60% and this drops to 10-15% for people with metastatic disease

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