A bladder polyp is a general term used by the public to describe any abnormal tissue growth or mass found on the inner lining of the bladder. These growths result from cells multiplying faster than normal to form a visible mass. While the presence of such a growth can be alarming, these masses are not all cancerous. The definitive nature of any bladder growth—whether benign or malignant—can only be confirmed through medical evaluation and testing. The discovery of a bladder mass necessitates prompt investigation due to the possibility of cancer.
Understanding Bladder Growths
Medical professionals often use specific terms such as “lesion,” “mass,” or “tumor” instead of the lay term “polyp” to describe abnormal bladder growths. A tumor describes any abnormal collection of cells that forms a mass, which may or may not be cancerous. The vast majority of clinically significant tumors arise from the urothelium, the specialized lining of the urinary tract.
Benign, or non-cancerous, growths exist in the bladder but are generally rare compared to malignant types. Examples include inflammatory pseudopolyps, which are masses formed by chronic inflammation or irritation rather than true tumors. Other benign tumors are named based on their tissue of origin, such as leiomyomas from smooth muscle or hemangiomas from blood vessels.
Prevalence of Malignancy Risk
Urothelial Carcinoma (UC), previously known as Transitional Cell Carcinoma, accounts for about 90% of all bladder cancer diagnoses. This high rate of malignancy means that when an abnormal bladder mass is found, the primary concern is ruling out this type of cancer by examining the tissue under a microscope.
Bladder tumors are broadly categorized into non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC). Approximately 75% of cases are non-muscle-invasive at presentation, meaning the growth is confined to the inner lining or the connective tissue layer. NMIBC tumors, such as papillary noninvasive (Ta) disease, have a high recurrence rate but a lower risk of progression. Muscle-invasive disease, where the tumor has spread into the deep muscle layer of the bladder wall, carries a significantly higher risk of spreading. Investigation focuses on identifying the specific type and depth of invasion to determine the risk and necessary treatment.
Identifying Common Symptoms
The most frequent sign that prompts a person to seek medical attention for a possible bladder growth is hematuria, the presence of blood in the urine. This blood may be visible (pink, red, or cola-colored) or microscopic, detectable only through lab testing. Painless visible blood in the urine is particularly noteworthy and should always lead to an evaluation.
A person may also experience irritative urinary symptoms, similar to those caused by a urinary tract infection. These changes include urinary frequency (an increased need to urinate) or urgency (a sudden, compelling need to urinate). Pain or a burning sensation during urination, termed dysuria, may also occur. While these symptoms can be caused by many benign conditions, their persistence warrants investigation to exclude a bladder tumor.
Diagnosis and Pathological Confirmation
The investigation process usually begins with a review of symptoms and a physical examination. Initial urine tests, such as urinalysis or urine cytology, check for microscopic blood or abnormal cells. The definitive visual examination of the bladder is performed using a procedure called cystoscopy.
During cystoscopy, a thin, flexible tube with a camera is inserted through the urethra into the bladder, allowing the doctor to visually inspect the inner lining for any masses. If an abnormal growth is identified, a surgical procedure known as Transurethral Resection of Bladder Tumor (TURBT) is typically performed.
The TURBT is both diagnostic and therapeutic, removing the visible tumor while collecting tissue samples for laboratory analysis. The removed tissue is sent to a pathologist for microscopic examination, which definitively confirms the nature of the growth. The resulting pathology report specifies if the mass is benign or malignant, and for cancerous tumors, details the type, grade, and depth of invasion. This confirmation dictates the subsequent course of treatment and follow-up care.