Luminal Bladder Cancer Effective Response to Neoadjuvant Chemotherapy (LUMBER-NAC)

The goal of this study is to assess the feasibility and oncologic safety of upfront radical cystectomy in luminal MIBC, using pathological upstaging (pT3-4 or pN+) and efficacy as the primary safety endpoints.

For patients with muscle-invasive bladder cancer (MIBC), the standard treatment remains sequential neoadjuvant therapy (NAT), which may include either cisplatin-based chemotherapy or novel approved combination regimens (i.e., chemotherapy and immunotherapy) followed by cystectomy. Although NAT improves overall survival, individual patient responses are heterogeneous (meaning not all patients experience the same benefit), and patients often experience morbidity.

In this study, the investigators will use the commercially available GSC- Decipher Bladder to analyze tumor tissue and determine the genomic subtype (luminal or basal).

Additionally, circulating tumor cell DNA (ctDNA) will be assessed at several time points in patients receiving NAT followed by RC, compared with those receiving upfront cystectomy.

Inclusion criteria

• ▪ Inclusion Criteria

• Willing and able to provide informed consent
• Age ≥18 years old
• Eligible to receive standard of care systemic neoadjuvant therapy
• Eastern Cooperative Group (ECOG) performance status of 0-1
• Documented histologically confirmed urothelial muscle-invasive bladder cancer
• cT2N0M0 bladder cancer based on pre-TURBT bimanual exam and cross-sectional imaging performed within 8 weeks of surgery or initiation of NAT.
• Willing to undergo RC with urinary diversion
• No signs of extravesical disease on pre-TURBT conventional imaging
• Variant histology is allowed so long as the tumor is predominantly urothelial carcinoma.
• No presence of LVI on TURBT
• Decipher Bladder GSC test result
• Ineligible for or refusing TMT
• No cN+
• The population is adult men or women of any ethnicity diagnosed with muscle-invasive bladder cancer.

Exclusion criteria

• Patients under 18 years old. Considering the minimal incidence of bladder cancer among the pediatric population, children are not eligible for this study.
• Not willing or unable to give informed consent.
• Clinical or pathological evidence of metastatic disease, including, non-regional lymph nodes, visceral lesions, and bone lesions.
• Significant hepatic impairment (Serum bilirubin > 1.5x upper limit of normal).
• Significant renal impairment (creatinine clearance <30 ml/min).
• Predominant variant histology (i.e. nested, micropapillary, sarcomatoid, plasmacytoid, small cell)6
• cT3 bladder cancer on pre-TURBT bimanual exam or with hydronephrosis on cross-sectional imaging performed within 8 weeks of surgery or initiation of NAT
• TURBT specimen with lymphovascular invasion (LVI) cT4 or unresectable bladder cancer
• Concurrent diagnoses of other, non-urothelial, malignancies or prior malignancy diagnoses within the past three years. Exceptions, determined at the discretion of the principal investigator, include squamous cell carcinoma, basal cell carcinoma, or other low-grade cancer not expected to progress or require surgical/systemic therapy.
• Prior history of systemic treatment for non-urothelial malignancies in the past three years, including chemotherapy and immunotherapy.
• Prior diagnosis or evidence of psychiatric or medical conditions that may prevent patients from giving full and properly informed consent.
• Any medical, familial, psychiatric, or geographic considerations that may prevent patients from study participation or follow-up required by the study protocol
• Patients (cN+) are excluded from participation and are not eligible for enrollment.
• Prisoners, Individuals without Decisional Capacity, and Pregnant Women will be excluded.