Urothelial Carcinoma - Types, Diagnosis, and Management

Introduction

Urothelial carcinoma is a type of cancer that begins in the urothelium which is the tissue lining parts of the urinary system. It accounts for about 90 percent of all bladder cancers and seven percent of all kidney cancers, including the ureter and renal pelvis. Kidney and bladder cancer caused by urothelial carcinoma has the same symptoms. If they are detected early, these cancers can be easily treated and have almost similar prognoses, and chances of recurrence are possible in both.

What Causes Urothelial Carcinoma?

The exact cause of urothelial carcinoma occurring in the bladder and kidneys is unknown. However, some of the risk factors of urothelial carcinoma include:

• Smoking Cigarettes - Cigarette smoking increases the risk of developing cancers in the urinary system linked to urothelial carcinoma.

• Certain Chemical Exposure - Studies have shown that people exposed to chemicals like rubber, dyes, leather, paint, hairdressing supplies, and textiles in their work atmosphere have an increased risk of cancers in the urinary system linked to urothelial carcinoma.

How Does Urothelial Carcinoma Affect a Person's Body?

Urothelial carcinoma affects a person's kidney and bladder in several ways.

• Urothelial Carcinoma Affecting a Person’s Bladder - A triangle-shaped organ situated above the urethra, between the hipbones, and below the kidneys is called a bladder. The urine released from the kidneys drains into the bladder which is lined by tissues called the urothelium. Urothelium consists of cells that undergo stretching whenever the bladder fills with urine and then get collapsed when it is empty. The bladder can at least hold two cups of urine. In the case of the bladder cancer, the abnormal urothelial cells start spreading from the inner lining of the bladder into the deeper layers. These cells also spread through the bladder wall into the surrounding fatty tissues of the bladder. If left untreated, this cancer can grow through the bladder walls to their nearby lymph nodes and other areas of the body including the liver, lungs, or bones. Bladder cancer can be of two types:

  • High-Grade Urothelial Carcinoma can be a life-threatening condition and also recur after treatment. It can spread into the lymph nodes, muscle layers of the bladder, and other areas of the body.

  • Low-Grade Urothelial Carcinoma can recur. However, it rarely spreads into the muscle layers or other parts of the body.

• Urothelial Carcinoma Affecting a Person’s Kidneys - The majority of people have two kidneys. Kidneys are organs situated below the rib cage and behind the belly area. This kidney clears toxins and other waste products from the body by producing urine which gets collected in the renal pelvis situated in the middle of both kidneys. From this area, the urine drains through a tube called the ureter which connects the kidney to the bladder. Like the kidneys, the ureter and renal pelvis are lined by urothelial tissue. In the case of kidney cancer, the abnormal cells form tumors in the kidney, ureter, or renal pelvis. Kidney cancer can spread to other tissue or organs.

What Are the Symptoms Seen in Urothelial Carcinoma?

Blood in the urine is the first noticeable symptom that occurs in urothelial carcinoma. Other symptoms include tiredness, persistent back pain, unexplained weight loss, painful urination, low-grade fever, and a mass or lump in the kidney area.

How Is Urothelial Carcinoma Diagnosed?

Certain tests are done to diagnose kidney and bladder cancer including urothelial carcinoma. The tests include:

• Urinalysis - This test is done to check the color of the urine and its contents like protein, sugar, blood, and bacteria.

• Urine Cytology - The doctor will examine the urine under a microscope to check for any abnormal cells. Cancer of the bladder or ureter and kidney cancer can shed cancer cells into the urine.

• Ureteroscopy - The doctor will use a narrow tube-like instrument containing a lens and a light to view the inside of the renal pelvis and ureter and to obtain tissue samples.

• Computed Tomography (CT) - The CT scan uses a computer that is linked to the X-ray machine to create detailed photos of areas inside the body.

• Ultrasound - This procedure uses a high-energy sound wave that bounces off the internal organs or tissues and creates echoes. These echoes form pictures of the body tissues called sonograms. Doctors usually perform an abdominal ultrasound to help diagnose cancer of the ureter and renal pelvis.

How Is Urothelial Carcinoma Managed?

Different treatment modalities exist for urothelial carcinoma of the kidneys, bladder, ureter, and renal pelvis.

• Bladder Cancer Management - Management of bladder cancer includes surgical intervention, chemotherapy, immunotherapy, radiation therapy, and targeted therapy. Surgical intervention includes the removal of tumors using high-energy electricity and burning them away in a process called fulguration.

• Kidney Cancer Management - Doctors manage kidney cancer the same way they manage bladder cancer. However, additional treatments include surgery, cryoablation, and radiofrequency ablation. In surgical intervention, the doctor might remove parts of the kidney containing cancer. In some cases, even the entire kidney might be removed.

• Ureter or Renal Pelvis Cancer Management - The surgeons will remove part of the ureter or renal pelvis containing the cancer cells.

What Is the Ureteroscopic Management of Urothelial Carcinoma?

• In recent years the endoscope has made a transition from being a diagnostic tool to a therapeutic aid in managing the upper urinary tract.

• Uteroscopic management is considered the first-line treatment for low-risk disease and is being utilized increasingly due to increasing surgical experience and technological advances.

• A low-risk urothelial carcinoma is defined as a unifocal disease consisting of a tumor of less than 2 cm in size, low grade on ureteroscopic biopsy, low-grade cytology, and on cross-sectional imaging, no invasive aspect was seen.

• The majority of bladder cancer patients with a low-grade, early-stage disease are managed endoscopically by the transurethral resection of the tumor present in the bladder.

• Endoscopic management can be done through a percutaneous approach or a ureteroscopic approach.

• Using diagnostic ureteropyeloscopy, patients with urinary tract disorders like benign bleeding lesions are being treated on a routine base with excellent success rates. An upper urinary tract urothelial malignancy undergoes endoscopic diagnosis by a no-touch technique.

• During ureteroscopy, visually the urothelial carcinoma can be differentiated from the benign processes. Ureteroscopic tissue samples will be able to provide specimens to differentiate inflammatory lesions from benign and malignant tumors, in case the diagnosis is uncertain.

• Although, the recurrence rate of upper tract lesions is common endoscopic management gives a 90 percent cancer survival rate for non-invasive upper tract urothelial carcinoma at 20 years in certain patients.

Conclusion

Urothelial carcinoma begins as abnormal cells in the tissue lining the kidney, bladder, renal pelvis, and ureter. This cancer causes 90 percent of bladder cancer and about 7 percent of kidney cancer including cancer that affects the ureter and renal pelvis. Both kidney and bladder cancer have the same symptoms and prognosis. They are easy to manage however the chances of recurrence are high in both of these cancers. In recent times ureteroscopic management of urothelial carcinoma has gained much popularity And is being considered the first-line treatment for a low-risk urothelial carcinoma.