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Upper Tract Tumors
Overview
Upper tract tumors develop in tissue in the kidneys that collects urine (i.e., the renal pelvis) and the tubes that carry urine from the kidneys to the bladder (ureters). Cancer that originates in the upper urinary tract accounts for less than 1% of cancers of the reproductive and urinary systems (genitourinary tract). Upper tract tumors are often associated with bladder cancer.
Types
More than 90% of renal pelvis tumors develop in surface lining cells (transitional epithelial cells). This type is called transitional cell carcinoma (TCC). TCC often develops in multiple areas of the upper urinary tract.
Fewer than 10% of renal pelvis tumors are squamous cell carcinomas, which develop in flat surface cells that line the renal pelvis. Adenocarcinoma, which develops in glandular cells, is extremely rare. These types of renal pelvis tumors are associated with inflammation caused by chronic urinary tract infections and kidney stones.
Incidence and Prevalence
According to the American Cancer Society, incidence of upper tract tumors is about 1-2 cases per 100,000 people each year. Renal pelvis tumors are more common in men and in Caucasians. Peak incidence occurs in the 60- to 70-year age group. The highest incidence is in Balkan countries such as Bulgaria, Greece, Yugoslavia, and Romania.
Upper tract tumors occurring on both sides (bilateral) account for less than 2% of cases.
Causes and Risk Factors
The cause of upper tract tumors is unknown. A personal history of bladder cancer is the primary risk factor. Smoking cigarettes is also a major risk factor. Smoking may contribute to as many as 60-80% of cases. Other risk factors include the following:
• Age
• Balkan descent
• Chronic urinary tract infections
• Family history of transitional cell carcinoma
• Genetic mutation of the p53 gene
• Overuse of analgesics that contain phenacetin
• Recurrent kidney stones
• Use of chemotherapy drugs cyclophosphamide and ifosfamide
People who work in chemical, petroleum, aniline dye, and plastics industries, and those exposed to coal, tar, and asphalt, also have an increased risk for upper tract tumors. Consuming more than seven cups of coffee a day may slightly increase the risk for the condition.
Signs and Symptoms
Blood in the urine (hematuria) is the most common symptom. Hematuria may be visible to the naked eye (gross) or visible upon examination with a microscope (microscopic). Other symptoms include bladder irritation, constipation, and pelvic pain.
Diagnosis
Diagnosis of upper tract tumors requires physical examination to detect tumors that are able to be felt with the fingers (palpable), laboratory tests, and imaging procedures. Laboratory tests include the following:
• Urinalysis (to detect microscopic hematuria)
• Urine cytology (to examine tissue cells found in urine for abnormalities)
• Urine culture (to rule out urinary tract infection)
Imaging procedures include computed tomography (CT scan) and intravenous pyelogram (IVP). CT scan uses x-rays to provide images of the urinary tract. It is used to distinguish kidney stones from upper tract tumors and to determine if a tumor has spread (metastasized).
Intravenous pyelogram is performed to detect a blockage in the urinary tract. In this procedure, a contrast agent (radiopaque dye) is administered intravenously and x-rays are taken as the dye moves through the urinary tract.
If an upper tract tumor is suspected, ureteroscopy and brush biopsy may be performed. Anesthesia is administered and a thin, telescope-like tube with a tiny camera attached (ureteroscope) is inserted into the ureter to allow the physician to detect abnormalities.
In a brush biopsy, a catheter is inserted into the ureter and tissue samples of suspicious lesions are taken using a small brush. The cells are examined under a microscope and the disease is staged if cancer is detected.
Treatment
The preferred method for treating most upper tract tumors is surgical removal of the kidney, ureter, and a portion of the bladder (nephroureterectomy). Partial removal of the ureter is not often recommended because there is a high risk for recurrence in the remaining portion.
Tumors that are confined to the lower third of the ureter may be treated using surgical removal of the ureter (ureterectomy) and surgical removal of regional lymph nodes (lymphadenectomy).
Patients with only one kidney and those with reduced kidney function, bilateral tumors (i.e., occurring on both sides), and metastatic upper tract tumors are not candidates for this procedure. These patients are treated using topical immunotherapy or chemotherapy.
Topical immunotherapy, also called biological therapy, is used to enhance the immune system’s ability to fight cancer. In this treatment, BCG, a vaccine derived from the bacteria that causes tuberculosis, is infused through a catheter into the upper urinary tract to stimulate the immune system to destroy cancer cells.
Side effects include inflammation of the bladder (cystitis), inflammation of the prostate (prostatitis), and flu-like symptoms. If high fever (over 101.5 °F) occurs, it may indicate that bacteria have entered the bloodstream (called bacteremia, a life-threatening condition that requires antibiotic treatment).
Chemotherapy is used after surgery to treat metastatic upper tract tumors and as primary treatment for inoperable tumors. Chemotherapy involves using toxic drugs to destroy cancer cells. A combination of methotrexate, vinblastine, doxorubicin, and cisplatin (M-VAC) is often used for upper tract tumors. These drugs may be injected, administered intravenously, or taken in pill form. Chemotherapy has many side effects, some of which are severe.
Radiation may be used to reduce pain (called palliative treatment) for upper tract tumors.
Prognosis
The prognosis for upper tract tumors depends on the stage of the disease at diagnosis. Untreated upper tract tumors are fatal. Tumors of the renal pelvis have a better prognosis than tumors of the ureter.
Prevention
Upper tract tumors cannot be prevented. Avoiding smoking and eliminating other known risk factors as well as chronic UTI and kidney stones can help prevent the condition.
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