Intravesical immunotherapy or chemotherapy for non-muscle invasive bladder cancer (NMIBC) is a well-established treatment for preventing or delaying tumor recurrence after tumor resection. For high-risk non-muscle invasive bladder cancer, immunotherapy in the form of intravesical Bacillus Calmette-Guérin (BCG) can be effective as first-line; nevertheless, the response rate to BCG is suboptimal with many patients failing treatment. Following BCG-failure, however, very few effective therapeutic options exist besides life-changing cystectomy. Recent shortages of BCG have pushed the use of alternative intravesical therapies for non-muscle invasive bladder cancer. At the University of Arizona Cancer Center, the use of intravesical Gemcitabine + Docetaxel (Gem/Doce) is considered as standard treatment for patients with non-invasive bladder cancer who are unable to get BCG or are BCG-resistant. The role of Gemcitabine as first-line treatment for NMIBC is poorly understood. The purpose of this study is to gain a better understanding of the use of Gemcitabine + Docetaxel intravesical chemotherapy for non-muscle invasive bladder cancer.

Inclusion Criteria:

1. Patients able to consent in English or Spanish; provision of signed and dated informed consent form

2. Stated willingness to comply with all study procedures and availability for the duration of the study

3. Male or female ages ≥18 years.

4. Patients with intermediate or high-risk non-muscle-invasive UC of the bladder and no previous BCG treatment.

   1. Histologically confirmed intermediate or high-risk non-muscle invasive urothelial carcinoma of the bladder (Ta, T1, or Tis stage) on Transurethral Resection of Bladder Tumor (TURBT) must be obtained within 180 days of registration. OR Patients with a high-grade recurrence after 24 months since last dose of BCG.

6. Eastern Cooperative Oncology Group (ECOG) performance status Grade 0-2. 7. Post-transurethral bladder tumor resection. 8. Evidence of post-menopausal status or negative urinary pregnancy test of female pre-menopausal patients is required. Women will be considered post-menopausal if they have been amenorrheic for 12 months without an alternative medical cause.

Exclusion Criteria:

1. Known hypersensitivity reaction to gemcitabine and/or docetaxel.
2. Clinical T2 or higher stage UC of the bladder.
3. Histopathology demonstrating any small cell component, pure adenocarcinoma, pure squamous cell carcinoma, or pure CIS of the bladder.
4. Active malignancies other than the disease being treated under study.
5. Subjects with concurrent upper urinary tract (i.e. ureter, renal pelvis) urothelial carcinoma of any stage.
6. Pregnant or breast-feeding women.
7. Has an underlying substance abuse or psychiatric disorder such that, in the opinion of the investigator, the patient would be unable to comply with the protocol.