Bladder cancer overview

# Overview
Bladder cancer refers to any of several types of malignant growths of the urinary bladder. Bladder cancer may be classified according to cell types into several subtypes: transitional cell carcinomas, squamous cell carcinomas, adenocarcinomas, small cell carcinoma, lymphoma, and sarcoma. The prevalence of bladder cancer is approximately 130.5 per 100,000 individuals in the United States. Males are more commonly affected with bladder cancer than females. Common risk factors in the development of bladder cancer are smoking, occupational exposure to chemicals, chronic bladder irritation, chemotherapy, radiation therapy, arsenic, personal history of cancer in the urinary tract, congenital bladder anomalies, and aristolochic acids. The most common symptoms of bladder cancer include hematuria, urinary frequency , urinary urgency, difficulty urinating, and dysuria. Common complications of bladder cancer include metastasis, anemia, hydronephrosis, urethral stricture, and urinary incontinence. The predominant therapy for bladder cancer is surgical resection. Adjunctive chemotherapy, radiation therapy, and immunotherapy may be required. Prognosis is generally good, and the 5-year survival rate is approximately 77.4%. The prognosis varies with the stages of tumor; carcinoma in situ have the most favorable prognosis.

# Classification
Bladder cancer may be classified according to cell types into several subtypes: transitional cell carcinomas, squamous cell carcinomas, adenocarcinomas, small cell carcinoma, lymphoma, and sarcoma.

# Pathophysiology
Genes involved in the pathogenesis of bladder cancer include HRAS, Rb1, PTEN/MMAC1, NAT2, and GSTM1. On gross pathology, flat lesions or papillary lesions are characteristic findings of non-invasive transitional cell carcinomas; a large infiltrative mass or a multifocal, flat to papillary lesion with delicate fronds are characteristic findings of invasive transitional cell carcinomas. On microscopic histopathological analysis, loss of cell polarity, nuclear crowding, and cytologic atypia are characteristic findings of flat lesion; fibrovascular stalks, umbrella cells, and eosinophilic cytoplasm are characteristic findings of papillary lesion; invasion beyond the basement membrane is the characteristic finding of invasive transitional cell carcinomas.

# Causes
There are no established causes for bladder cancer.

# Differential Diagnosis
Bladder cancer must be differentiated from renal cancer, renal stones, prostate cancer, and cystitis.

# Epidemiology and Demographics
The prevalence of bladder cancer is approximately 130.5 per 100,000 individuals in the United States. The incidence of bladder cancer is approximately 20.3 per 100,000 individuals in the United States. The incidence of bladder cancer increases with age; the median age at diagnosis is 73 years. Males are more commonly affected with bladder cancer than females. Bladder cancer usually affects individuals of the white race. African American, Asian, and Hispanic individuals are less likely to develop bladder cancer.

# Risk Factors
Common risk factors in the development of bladder cancer are smoking, occupational exposure to chemicals, chronic bladder irritation, chemotherapy, radiation therapy, arsenic, personal history of cancer in the urinary tract, congenital bladder anomalies, and aristolochic acids.

# Screening
According to the the U.S. Preventive Service Task Force (USPSTF), there is insufficient evidence to recommend routine screening for bladder cancer.

# Natural History, Complications and Prognosis
Common complications of bladder cancer include metastasis, anemia, hydronephrosis, urethral stricture, and urinary incontinence. Prognosis is generally good, and the 5-year survival rate is approximately 77.4%. The prognosis varies with the stages of tumor; carcinoma in situ have the most favorable prognosis.

# History and Symptoms
The most common symptoms of bladder cancer include hematuria, urinary frequency , urinary urgency, difficulty urinating, and dysuria.

# Physical Examination
Common physical examination findings of bladder cancer include cachexia, pallor, and a pelvic mass may be palpated.

# Staging
Bladder cancer may be classified into several subtypes based on TNM system.

# Laboratory Findings
Laboratory findings consistent with the diagnosis of bladder cancer include blood in the urine, abnormal cells in the urine, and elevated tumor markers.

# X Ray
Chest X-ray may be performed to detect metastases of bladder cancer to the lungs.

# CT Scan
CT scan may be helpful in the diagnosis of bladder cancer.

# MRI
MRI may be helpful in the diagnosis of bladder cancer.

# Ultrasound
There are no ultrasound findings associated with bladder cancer.

# Other Imaging Findings
There are no other imaging findings associated with bladder cancer.

# Other Diagnostic Studies
There are no other diagnostic study findings associated with bladder cancer.

# Biopsy
Biopsy is helpful in the diagnosis of bladder cancer.

# Medical Therapy
The predominant therapy for bladder cancer is surgical resection. Adjunctive chemotherapy, radiation therapy, and immunotherapy may be required.

# Surgery
Surgery is the mainstay of treatment for bladder cancer.

# Primary prevention
Primary prevention strategies of bladder cancer include cease smoking, avoid aristolochic acids, and avoid exposure to industrial chemicals and arsenic.

# Secondary prevention
There are no secondary preventive measures available for bladder cancer.