In short
Benign tumors of the ureter are rare growths that develop in the tubes connecting your kidneys to your bladder. Unlike cancerous tumors, these growths don't spread to other parts of the body, but they can still cause significant problems with urine flow and kidney function.
What is a Benign Neoplasm of the Ureter?
A benign neoplasm of the ureter is a growth that develops in the ureter but is not cancerous. The term "benign" means that the tumor is made from normal, intact cells rather than abnormal cells. These tumors can grow to large sizes, but they do not spread beyond the organ where they started.
The ureter is a tube that carries urine from your kidney to your bladder. You have two ureters, one connected to each kidney. In most males, each ureter is about 8 inches long, while in females it is about 2 inches long. When a benign tumor develops in the ureter, it can interfere with the normal flow of urine.
A benign neoplasm is characterized by the absence of unusual or harmful cell features, and it does not have the ability to invade nearby tissues or spread to distant parts of the body (a process called metastasis).
Medical Classification
MONDO:0001398 C0154016 D30.2
Benign Neoplasm of the Ureter, Benign Tumor of the Ureter, Benign Tumor of Ureter, Benign Ureter Neoplasm, Benign Ureter Tumor, Benign Ureteral Neoplasm, Benign Ureteral Tumor
Associated Anatomy
- Ureter
- Kidney
- Bladder
Types of Benign Ureter Tumors
Benign tumors of the ureter are uncommon. They most often appear in the form of fibroepithelial polyps, which represent from 2 to 6% of all benign tumors of the urinary tract.
Fibroepithelial polyps are benign tumors that originate from tissue of mesodermal origin, which is the middle layer of embryonic tissue. This group of tumors also includes other rare types such as angiomatous polyps, leiomyomas, hemangiomas, neurofibromas, lymphangiomas, granulomas and endometriomas.
Fibroepithelial polyps are more commonly found in the ureteropelvic junction (where the ureter connects to the kidney) or in the upper ureter. They can also occur in the renal pelvis, which is the central collecting area inside the kidney. Most of these tumors are single growths, but there have been reports of multiple fibroepithelial polyps affecting both the pelvis and ureter.
Causes and Risk Factors
The exact causes of benign ureter tumors are still not fully understood. Several factors have been suggested as possible causes, including allergy, trauma, exposure to substances that cause cancer, and hormonal imbalances.
Some medical experts believe these tumors may have a birth-related origin due to abnormal development during pregnancy. Others think they may develop from irritation caused by kidney stones.
Different sources report varying information about who is more likely to develop these tumors. Some research indicates they are more common in women and typically occur on one side only. Other studies have found fibroepithelial polyps more often in young men.
These tumors tend to occur most often in adults between 20 and 40 years of age. However, they can arise in children and have even been reported in newborn babies.
Signs and Symptoms
The most common symptoms of benign ureter tumors are blood in the urine (called hematuria) and pain in the side of the lower back or abdomen (called flank pain).
When blood appears in the urine, it may be visible to the naked eye or only detectable through laboratory testing (microscopic hematuria). Patients may notice their urine is stained a faint pink color, or they may see red streaks or clots in their urine. These symptoms gradually increase over time until they become very noticeable.
Pain may come and go because the tumor causes partial blockage of the ureter. Sometimes the pain is associated with symptoms that suggest kidney stones. This intermittent pain occurs because the tumor obstructs urine flow at times.
One type of benign ureter tumor can cause acute urinary retention (inability to pass urine) along with heavy bleeding in the urine.
If the urinary tract becomes blocked by a blood clot or by the tumor itself, this can lead to a condition called hydronephrosis. In hydronephrosis, urine backs up and causes swelling in the kidney's collecting area (the renal pelvis) and the small tubes inside the kidney (calyces). Over time, this can lead to damage and shrinkage of kidney tissue.
How is it Diagnosed?
Diagnosing benign ureter tumors requires several tests and procedures. A physical examination alone cannot detect a mass or enlarged kidney by touching the abdomen.
Doctors use a combination of blood tests, urine analysis (called urinalysis), ultrasound imaging, and other scanning techniques to make a diagnosis. These diagnostic tools may include:
- Abdominal CT scan (computerized tomography scan)
- Abdominal MRI (magnetic resonance imaging)
- Blood test
- Intravenous pyelogram (IVP)
- Kidney ultrasound
- Renal scan
- Urinalysis
A procedure called ureteroscopy may be performed. During this procedure, a healthcare professional inserts a thin, lighted tube equipped with a camera into the urethra (the tube through which urine exits the body). The device is passed through the bladder and into the ureters. This allows the doctor to see inside the ureters and look for abnormal growths.
If a suspicious growth is found, a biopsy may be taken during the ureteroscopy. A biopsy involves removing a small sample of tissue for examination under a microscope to determine whether the tumor is benign or malignant.
Treatment Options
Treatment for benign ureter tumors depends on the size and location of the tumor, as well as whether the base of the tumor can be clearly identified.
Surgical Treatment
The most common approach to treating benign ureter tumors is surgery. The type of surgical procedure depends on the specific characteristics of the tumor.
For some tumors, open surgery with partial removal of the ureter may be necessary. In cases where only the tumor and a small segment of the ureter are removed, this is called segmental ureterectomy resection. If the tumor is small and confined to one area, it may be possible to remove only the part of the ureter that contains the growth.
When the base of the polyp is well identified, the tumor can be treated using an endoscopic approach. This is a minimally invasive technique where a flexible tube is inserted through the urethra to reach the tumor, avoiding the need for large incisions.
Some cases may require more extensive surgery. If the tumor has caused significant damage or complications, removal of the entire kidney (nephrectomy) may be necessary. In other situations, the kidney, ureter, and upper part of the bladder may all need to be removed in a procedure called nephro-ureterectomy.
Alternative Approaches
In certain situations, doctors may use laser therapy to destroy the tumor cells. This approach involves deploying a laser at the end of a flexible tube inserted through the urethra or through a small incision in the abdomen.
The choice of treatment depends on the tumor's location, size, and the patient's overall health. The goal is to remove the tumor while preserving as much normal kidney and ureter function as possible.
