Blue light cystoscopy in patients with suspected non-muscle invasive bladder carcinoma: a review of clinical utility

According to Canadian Cancer Statistics, bladder cancer is the fifth most common cancer, accounting for more than 4% of all cancers or 7,800 cases per year.1 Of all incidents of bladder cancer cases at first diagnosis, about 80% were non-muscle invasive bladder cancer (NMIBC) and 20% were muscle inv...

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Bibliographic Details
Main Author: Tran, Khai
Corporate Author: Canadian Agency for Drugs and Technologies in Health
Other Authors: Severn, Melissa
Format: eBook
Language:English
Published: Ottawa (ON) Canadian Agency for Drugs and Technologies in Health 2017, February 15, 2017
Edition:Verions: 1.0
Series:CADTH apid response report: summary with critical appraisal
Subjects:
Online Access:
Collection: National Center for Biotechnology Information - Collection details see MPG.ReNa
Description
Summary:According to Canadian Cancer Statistics, bladder cancer is the fifth most common cancer, accounting for more than 4% of all cancers or 7,800 cases per year.1 Of all incidents of bladder cancer cases at first diagnosis, about 80% were non-muscle invasive bladder cancer (NMIBC) and 20% were muscle invasive and advanced bladder cancer.2 Smoking is the main risk factor of bladder cancer.2,3 Other risk factors include exposure to chemicals such as aromatic compounds, radiation and chemotherapy.2,3 The most common symptom of bladder cancer is the presence of blood in the urine.2 Bladder cancer is diagnosed by means of cystoscopy and transurethral resection of the bladder tumor (TURBT) in combination with urine analysis and cytology.2,4 The tumors are classified based on the degree of invasion into layers of tissues; CIS (flat on surface or carcinoma in situ), Ta (raspberry growth on surface), and T1 (moves into submucosa layer) are those not yet invading into the muscle or NMIBC,
while T2a, T2b, T3b and T4a are those invade deeper into the muscle layer and perivesical fat tissue.2 About 60% of NMIBC are Ta type, while CIS and T1 account for 10% and 30%, respectively.3 After the initial removal of NMIBC by TURBT, tumors can come back (recurrence) or come back and invade into the muscle layer (progression).2 Tumors are graded based on the risk of progression and metastasis.3 For instance, Ta tumors are usually low grade (non-aggressive) but have high risk of recurrence and just require repeated scraping, while CIS and T1 tumors are high grade (aggressive), have a high risk of progression to muscle layer and require more aggressive treatment.2 Visibility of tumors is very important during TURBT,
in particular flat lesions such as CIS or low-graded tumors are often missed under standard white light cystoscopy.5 A new technique termed "blue light" cystoscopy have been introduced to improve the visibility of tumors by using a photosensitizing agent and fluorescent light in the photodynamic diagnosis of NMIBC.4 In fluorescent cystoscopy, the photosensitizing agent such as 5-aminolevulenic acid (5-ALA) or hexaminolevulinate (HAL), a derivative of 5-ALA, are first instilled into the bladder.4 The drug then incorporates into the urothelial cytoplasm where abnormal cells appear red and normal cells appear blue green upon illumination with fluorescent light.4 Thus, "blue light" or fluorescent cystoscopy may help the detection of tumors more accurately and may reduce the risk of recurrence and progression compared to white light cystoscopy.
HAL needs a much shorter instillation time than 5-ALA and has been approved only for detection of bladder cancer in Europe and USA since 2010.4 HAL, branded as Cysview, has been approved by Health Canada since November 2015 as an adjunct to cystoscopy for the detection of NMIBC in patients with known or suspicion of bladder cancer.6,7 The aim of this report is to review the clinical utility of "blue light" cystoscopy in patients with suspected NMIBC undergoing TURBT.
Physical Description:1 PDF file (15 pages)