How is bladder cancer diagnosed?

Dr Daleen Geldenhuys lists the various diagnostic tests that may be done to diagnose bladder cancer.

You can listen to this article below, or by using your favourite podcast player at pod.link/oncologybuddies

The diagnosis of any cancer starts with acting on abnormal symptoms and reporting those to your general practitioner. 

Bladder cancer symptoms

Haematuria (blood in urine), even if only at the end of urination should be investigated. Occasionally only staining of the undergarment may be the only blood seen. Bladder infections, bacterial or even bilharzia infections, can also present with bleeding but in general, that should also be reported to the primary care physician. 

Bladder and pelvic pain or discomfort and being aware of your bladder all the time is suspicious. Pain may radiate to the flanks and not be central. Suprapubic pain (pain in the lower abdomen, above the pubic bone and below the belly button) may be a sign of local extension of the tumour. Invasion of the complex nerve system around the bladder neck may cause incontinence but may also cause urinary retention (unable to pass urine despite a large volume of urine in the bladder).

Voiding symptoms, the feeling of not being able to empty your bladder, with residual urine only emptying if you change position, indicates a non-compliant, non-contractile organ. Irritative voiding, such as urge incontinence appear in about a third of patients. 

Bladder cancer may involve other organs, such as the prostate and the rectum that lies directly behind it in men or the cervix and vagina in women. Pain or difficulty passing stool, may also be a sign. Often the blood in the urine disappears for a week or so and may make you think that all is well. Don’t ignore it.

Symptoms such as fatigue, weight loss, and no appetite are usually signs of advanced or metastatic disease and denotes a poor prognosis. In rare cases, patients may have constitutional symptoms due to kidney failure caused by bilateral ureteral obstruction. 

Causes of bladder cancer 

This includes a number of different causes. Chemical exposure, such as smoking, the main cause, including secondary smoke, opium users, and occupational exposure to pathogens. 

At risk occupations are metal workers, painters, rubber industry workers, leather workers, textile and electrical workers, miners, cement workers, transport operators, excavating-machine operators, and jobs that involve manufacture of carpets, paints, plastics, and industrial chemicals that include benzene, polyaromatic hydrocarbons, and diesel exhausts.

Diagnostic evaluation

Bedside evaluation with a urine dipstick as well as observation of macroscopic blood seen in the urine sample. This should be sent for microscopy, culture, and even cytology if the clinician suspects a non-benign diagnosis.

Cystoscopy (a procedure to examine the inside of the bladder and urethra) is the initial procedure for both the diagnosis and management of urothelial malignancy. Cystoscopy is used to establish the diagnosis, assess whether or not muscle invasion is present, and provide initial therapy for non-muscle invasive lesions. 

Urine cytology (test that examines urine samples for abnormal cells) is widely used in combination with cystoscopy to assess for the presence of carcinoma in situ and to evaluate for the presence of upper urinary tract lesions.

Tissue biopsy of the lesions in the bladder or if more advanced, lymph nodes or other organs involved. This allows better characterisation of the tumour and also specifies whether the tumour is transitional carcinoma, squamous carcinoma, or infiltrative from direct extension from e.g. colonic or prostatic origin.

CT scan is the preferred imaging procedure to assess the local extent of disease and to further examine the renal pelvis and ureters. 

MRI scan of the pelvis will assist to see if the tumour is localised or invasive into the bladder muscle.

FDG PET-CT scan is only useful for metastatic workup as the bladder fills with the tracer very quickly and will mask disease in the bladder.

Remember, diagnosis depends on early detection of this cancer. As there are no screening programmes, even for patients at risk, the key factor in making the diagnosis is prompt reporting from the patient and high level of suspicion from the general practitioner.