While new FDA-approved intravesical treatments like nadofaragene firadenovec and TAR-200 demonstrate high complete response rates initially, their effectiveness consistently diminishes over time. This highlights the ongoing challenge of achieving durable, long-term bladder preservation.

Upcoming trials like RETAIN and IMVigor011 are using circulating tumor DNA (ctDNA) to guide complex treatment choices in muscle-invasive bladder cancer. This biomarker-driven approach aims to personalize therapy, potentially enabling bladder preservation for some patients and identifying others who need additional adjuvant treatment.

Historically, bladder-sparing options were primarily for patients unfit for radical cystectomy. Now, with advances in surgical techniques and perioperative care, fewer patients are deemed truly ineligible for surgery. This shift means new bladder-sparing strategies are being developed for a much broader patient population.

While bladder preservation is a key goal, there is an unavoidable risk. Forgoing definitive local treatment like surgery means a subset of patients will not be cured by systemic therapy alone and will miss their opportunity for a potentially curative operation, a crucial ethical consideration.

In early-stage bladder cancer, where the goal is a cure, the argument to "save a therapy for later" is flawed. The primary objective should be to use the most effective treatment upfront. Withholding it doesn't make it more effective upon relapse; it just gives the cancer an opportunity to progress.

High relapse rates (~70%) in surgery-alone arms of recent trials suggest most patients with muscle-invasive bladder cancer (MIBC) already have micrometastatic disease. This reframes the disease, prioritizing early systemic therapy over immediate surgery to achieve control and potential cure.

By improving response rates before surgery, adding intravesical BCG can reduce the number of patients requiring follow-up adjuvant systemic therapy. This de-escalation strategy limits patients' overall exposure to toxic treatments and their side effects, a key benefit beyond improving primary outcomes.

In high-risk non-muscle invasive bladder cancer (NMIBC), trials like CREST and POTOMAC show adding a systemic immune checkpoint inhibitor to BCG therapy introduces significant toxicity. The benefit is primarily in local control, which may not justify the risk, especially with other effective intravesical options available.

The success of new treatments like immunotherapy and ADCs leads to more patients achieving a deep response. This high efficacy makes patients question the necessity of a radical cystectomy, a life-altering surgery, creating an urgent need for data-driven, bladder-sparing protocols.