Conventional TURBT vs En Bloc TURBT for Non-Muscle-Invasive Bladder Cancer
En bloc resection of bladder tumor (ERBT) offers superior specimen quality with higher rates of detrusor muscle inclusion (>95%) compared to conventional TURBT, making it the preferred technique for non-muscle-invasive bladder cancer when equipment and trained operators are available.
Key Differences Between Techniques
Conventional TURBT
- Technique: Tumors are resected in fractions, especially for larger tumors (>1 cm)
- Specimen Collection: Multiple specimens sent in separate containers 1
- Muscle Inclusion: Variable rates of detrusor muscle in specimen
- Residual Tumor Risk: Higher rates of residual tumor (17-71% depending on stage) 1
- Recurrence Risk: Higher recurrence rates, particularly at the same site
En Bloc TURBT
- Technique: Complete removal of tumor as a single piece with underlying detrusor muscle
- Specimen Quality: Superior pathological specimens with intact architecture 2
- Muscle Inclusion: Consistently high rates of detrusor muscle (>95%) 2
- Energy Sources: Can be performed using:
- Bipolar electrocautery
- Various laser technologies (holmium, thulium)
- Advantages:
- Better histopathological assessment
- Potentially lower recurrence rates
- Reduced risk of tumor cell seeding 3
Clinical Outcomes Comparison
Specimen Quality
- En bloc provides significantly higher rates of detrusor muscle inclusion (>95% vs variable rates) 2
- Better preserved tumor architecture for pathological assessment
- Potentially more accurate staging
Recurrence Rates
- Limited comparative data on recurrence rates
- Extended TURBT protocols show recurrence in the same area as primary tumor in only 5.1% of cases 4
- En bloc technique may reduce tumor cell implantation during resection
Complications
- Similar perioperative morbidity between both techniques 2
- Laser-based en bloc techniques may reduce obturator nerve reflex risk, particularly useful for lateral wall tumors 3
Indications and Patient Selection
Ideal Candidates for En Bloc TURBT
- Smaller tumors (<3 cm)
- Lateral wall tumors (when using laser techniques)
- Patients requiring high-quality specimens for accurate staging
Conventional TURBT Still Preferred For:
- Very large tumors (>3 cm)
- Multiple tumors in difficult locations
- Settings without access to en bloc equipment or expertise
Practical Considerations
Equipment Requirements
- En bloc requires specialized equipment:
- Bipolar electrocautery systems
- Laser systems (holmium, thulium)
- Conventional TURBT has wider availability in most centers 3
Technical Expertise
- En bloc has a steeper learning curve
- Conversion to conventional technique may be necessary for larger tumors
Recommendations for Clinical Practice
For initial diagnosis and small tumors: En bloc resection is preferred when available due to superior specimen quality
For all TURBT procedures: Ensure resection includes detrusor muscle (except for TaG1/low-grade tumors) 1
Repeat TURBT indications (regardless of technique):
- Incomplete initial TURBT
- No muscle in specimen (except TaG1/low-grade)
- T1 tumors
- G3/high-grade tumors 1
Documentation requirements:
- Number, location, and size of tumors
- Use of bladder diagram recommended
- Separate submission of tumor base to confirm muscle presence 1
Common Pitfalls to Avoid
- Failing to obtain adequate tissue samples including detrusor muscle
- Underestimating need for repeat TURBT in high-risk tumors
- Excessive cauterization causing tissue destruction and hampering pathological assessment 1
- Not submitting specimens from different fractions in separate containers
En bloc TURBT represents an evolution in surgical technique that addresses some limitations of conventional TURBT, particularly regarding specimen quality and potentially recurrence rates. While not yet universally adopted, the technique shows promise in improving the management of non-muscle-invasive bladder cancer.