Management of Bladder CIS After BCG Induction
For a 60-year-old man with CIS of the bladder who received an induction course of BCG with no residual tumor on follow-up biopsy and mild atypia on cytology, maintenance BCG therapy should be initiated with three weekly instillations at months 3,6, and 12, and continuing with three weekly instillations every 6 months for up to 3 years. 1, 2
Rationale for Maintenance BCG Therapy
The NCCN guidelines strongly recommend maintenance BCG therapy for patients with high-risk non-muscle invasive bladder cancer (including CIS) who have responded to induction therapy 1. This recommendation is based on evidence that:
- An induction course of BCG followed by a maintenance regimen produces better outcomes than intravesical chemotherapy alone 1
- Maintenance therapy significantly reduces disease recurrence and progression compared to induction therapy alone 1
- For high-risk patients (including those with CIS), 3-year maintenance BCG reduced recurrence compared with 1-year maintenance 1
Recommended Maintenance Schedule
The optimal maintenance schedule based on the strongest evidence is:
- Three weekly instillations at months 3,6, and 12 after induction
- Continue with three weekly instillations at months 18,24,30, and 36 2
This schedule is based on the SWOG trial regimen that demonstrated reduced disease progression and metastasis 1.
Monitoring During Maintenance Therapy
- Regular cystoscopy and urinary cytology every 3 months for the first 2 years
- Then every 6 months for years 3-4, and annually thereafter 2
- Upper tract imaging at least once within the first 2 years 2
Important Considerations
Response Assessment
- Complete response is defined as no visible tumor on cystoscopy, negative cytology, and negative biopsies 2
- If cytology becomes positive during follow-up but cystoscopy remains negative, selected mapping biopsies are indicated 2
BCG Toxicity Management
- Full-dose BCG is recommended by the NCCN panel 1
- If significant local symptoms develop during maintenance, dose reduction may be considered 1
- Symptom management with single-dose, short-term quinolones and/or anticholinergics can reduce adverse events 1
Management of Recurrence
- If recurrence is detected during maintenance therapy, consider a second course of BCG induction (maximum of 2 consecutive courses) 2
- For persistent high-grade T1 tumors after a second course, cystectomy is recommended 1
- For persistent CIS or Ta disease after a second course, options include cystectomy or changing the intravesical agent 1
Why Option C is Correct
Among the given options, option C (three weeks of BCG at three and six months, then every six months for two years) most closely aligns with the evidence-based maintenance schedule recommended by current guidelines. This schedule follows the established SWOG protocol that has demonstrated the best outcomes in reducing disease progression and metastasis 1, 2.
Option A (cystoscopy and cytology in three months) is inadequate as it does not include maintenance therapy, which is strongly recommended for CIS patients who have responded to induction 1.
Option B (monthly BCG for one year) represents an excessive and non-standard maintenance schedule that could increase toxicity without proven additional benefit 1.
Option D (intravesical mitomycin C) would be appropriate only after BCG failure, not as first-line maintenance therapy 1.
Option E (additional six weeks of BCG) would constitute a second induction course, which is only indicated for persistent or recurrent disease, not for patients who have already shown complete response 1.