Bladder Cancer: Causes, Symptoms, Diagnosis and Treatment — Overview, Diagnosis & Treatment Options | MyMedicPlus

Bladder cancer is the 6th most common cancer in the United States, with approximately 82,000 new cases and 17,000 deaths annually. It is the 4th most common cancer in men. Over 90% are urothelial (transitional cell) carcinoma (UC) — arising from the transitional epithelium (urothelium) lining the bladder, ureters, and renal pelvis — with the remainder comprising squamous cell carcinoma (5%), adenocarcinoma (2%), and small cell carcinoma. The disease shows a striking male predominance (approximately 4:1 male-to-female ratio), likely reflecting greater historical occupational and tobacco exposure. The majority (approximately 75%) of bladder cancers are diagnosed as non-muscle-invasive bladder cancer (NMIBC) — confined to the bladder mucosa and lamina propria (stages Ta, T1, and carcinoma in situ/CIS) — which carries a good prognosis but has the highest recurrence rate of any solid tumor (50-70% recur within 5 years), requiring lifetime surveillance cystoscopy. The remaining 25% are muscle-invasive (MIBC, T2-T4) at presentation and carry substantially higher mortality without multimodal treatment (radical cystectomy or bladder-preserving chemoradiation). The management of metastatic bladder cancer was transformed by the EV-302 trial (2024), which established enfortumab vedotin plus pembrolizumab as the new first-line standard with median OS of approximately 31 months — unprecedented in this disease. Additional molecularly targeted approaches include erdafitinib (FGFR3/2 inhibitor) for FGFR-altered disease and atezolizumab/pembrolizumab maintenance after platinum chemotherapy.

Cigarette smoking is the dominant risk factor, accounting for approximately 50% of all bladder cancer cases — tobacco carcinogens including aromatic amines (4-aminobiphenyl, 2-naphthylamine, benzidine) and nitrosamines are metabolized and excreted in the urine, chronically bathing the urothelium; risk increases with pack-year exposure and is dose-dependent; risk decreases progressively after cessation, returning to near-baseline after 15-20 years. Occupational exposure to aromatic amines: workers in rubber manufacturing, dye and textile industries, leather processing, printing, hairdressing, and chemical and petroleum industries have 2-10 fold elevated bladder cancer risk from carcinogenic amine exposure; historically, benzidine (a bladder carcinogen) was used in the dye industry; occupational bladder cancer typically has a 30-50 year latency. Other established risk factors: pelvic radiotherapy (for cervical, prostate, or rectal cancer) — 2-4 fold increased risk with approximately 10-15 year latency; cyclophosphamide chemotherapy — acrolein metabolite concentrated in urine damages urothelium, causing hemorrhagic cystitis and urothelial carcinoma risk; risk reduced by Mesna (sodium 2-mercaptoethane sulfonate) prophylaxis; chronic catheterization or recurrent urinary tract infections associated with squamous metaplasia and squamous cell carcinoma; Schistosoma haematobium infection — endemic in sub-Saharan Africa and parts of the Middle East — causes squamous cell carcinoma of the bladder (not transitional cell) through chronic granulomatous inflammation; arsenic-contaminated drinking water (above 300 μg/L) substantially increases risk. Genetic risk: FGFR3 mutations are the most common somatic alteration in low-grade NMIBC (approximately 60-80%); TP53 and RB1 mutations predominate in high-grade and invasive tumors; ERBB2 (HER2) amplification in approximately 10-20%; TERT promoter mutations in approximately 60-80% of all UC; CDH1 loss, ARID1A, KDM6A, and chromatin remodeling gene mutations in muscle-invasive disease. Lynch syndrome (MMR germline mutations) increases upper tract urothelial carcinoma risk more than bladder risk, but is associated with bladder UC risk.

Painless gross hematuria — visible red, brown, or pink urine — is the cardinal presenting symptom of bladder cancer, occurring in approximately 85% of patients; the bleeding is typically intermittent and may spontaneously resolve, falsely reassuring both patient and clinician; any single episode of gross hematuria in an adult warrants urological evaluation. Microscopic hematuria (blood detected only on urinalysis, above 3 red cells per high-power field): detected incidentally on dipstick or microscopy; significant bladder cancer risk in older patients — approximately 5-10% of patients with microscopic hematuria above 25 red cells/hpf have significant urological pathology. Irritative lower urinary tract symptoms: urinary frequency (voiding more than 8 times in 24 hours), urgency (sudden compelling need to void), dysuria (painful urination), and nocturia — these symptoms, particularly without an identifiable infective cause (negative urine culture), strongly suggest carcinoma in situ (CIS, Tis) of the bladder which invades the urothelium diffusely and produces these irritative symptoms; CIS is particularly aggressive (60-80% progress to muscle-invasive disease if untreated). Advanced local disease (MIBC, T2-T4): pelvic pain or pressure from direct tumor extension into perivesical fat or adjacent organs (uterus, rectum, prostate); hydronephrosis from ureteral orifice obstruction causing flank pain; bladder outflow obstruction with urinary retention; fistula formation (vesicovaginal, vesicorectal). Metastatic bladder cancer: bone pain (axial skeleton most common), lower extremity lymphedema from pelvic lymph node obstruction, leg edema from common iliac lymph node involvement, hepatomegaly from liver metastases, and dyspnea from pulmonary metastases. Constitutional features of advanced disease: progressive weight loss, fatigue, anorexia, and cachexia. Upper tract urothelial carcinoma (renal pelvis, ureter) may present with hematuria and flank pain without bladder symptoms — whole urological tract CT urogram is essential in the hematuria workup.

Flexible cystoscopy is the gold standard diagnostic procedure — direct endoscopic visualization of the bladder mucosa identifies papillary lesions, flat erythematous areas (suggestive of CIS), and the number, size, and location of tumors; a normal cystoscopy in the presence of gross hematuria mandates upper tract imaging. Urine cytology: cytological examination of voided urine or bladder washings for malignant cells — high sensitivity (~80%) and specificity for high-grade UC; low sensitivity (~20-40%) for low-grade NMIBC; Paris System 2022 standardizes cytological reporting. Urine biomarkers (UroVysion FISH, NMP22, BTA): supplementary tests for surveillance in known NMIBC; not yet recommended as primary screening tools. CT urogram (CTU, CT urography): multiphase CT with late-phase excretory images of the entire urothelial tract — required for hematuria workup to exclude upper tract urothelial carcinoma (UTUC), renal tumors, and ureteral lesions. Transurethral resection of bladder tumor (TURBT): both diagnostic and initial treatment — endoscopic resection of all visible tumors with submission of detrusor muscle in the specimen (confirming depth of invasion); must include muscle in the specimen to distinguish T1 (superficial) from T2 (muscle-invasive) disease; repeat TURBT in 4-6 weeks for high-grade T1 tumors to confirm absence of residual muscle-invasive disease. MRI of pelvis (multiparametric, mpMRI with diffusion-weighted imaging): superior to CT for local staging of MIBC — T2, T3, T4 staging and assessment of perivesical fat and adjacent organ involvement; bladder MRI imaging reporting system (VIRADS) provides standardized assessment of muscle-invasion probability. CT chest-abdomen-pelvis: metastatic staging for all MIBC patients — lymph nodes, liver, lung, and bone assessment. Bone scan or whole-body MRI: for bone metastasis assessment when symptomatic. AJCC 8th edition TNM: Ta (non-invasive papillary), Tis (carcinoma in situ), T1 (lamina propria invasion), T2a/b (superficial/deep muscle invasion), T3a/b (microscopic/macroscopic perivesical fat), T4a (prostate stroma, seminal vesicle, uterus, vagina), T4b (pelvic or abdominal wall invasion). Molecular biomarkers: FGFR3/2 mutation status (erdafitinib eligibility), PDL1 expression (IHC, for pembrolizumab/atezolizumab NMIBC use), TMB, and MSI-H assessment.

Non-muscle-invasive bladder cancer (NMIBC): transurethral resection of bladder tumor (TURBT) with intraoperative single-dose intravesical mitomycin C instillation immediately post-resection (within 6 hours) for low-risk disease reduces recurrence by 30%. High-risk NMIBC (high-grade T1, CIS, large or multifocal high-grade Ta): BCG (Bacillus Calmette-Guerin, attenuated Mycobacterium bovis) intravesical immunotherapy — 6-week induction course plus maintenance for 1-3 years (SWOG S8795 schedule: 3 weekly instillations at 3 months, 6 months, and then twice-yearly for 3 years); BCG reduces disease progression by 27% and improves OS vs mitomycin C in meta-analysis; BCG shortage alternative: intravesical nadofaragene firadenovec (gene therapy, FDA-approved 2022) or cretostimogene. BCG-unresponsive NMIBC (persistent high-grade disease after adequate BCG): pembrolizumab 200 mg IV every 3 weeks FDA-approved for BCG-unresponsive CIS; radical cystectomy recommended for T1 BCG failure. Muscle-invasive bladder cancer (MIBC, T2-T4a N0 M0): neoadjuvant cisplatin-based chemotherapy (gemcitabine plus cisplatin, 4 cycles; or dose-dense MVAC — methotrexate, vinblastine, doxorubicin, cisplatin) followed by radical cystectomy (total cystoprostatectomy in men, anterior exenteration in women) with pelvic lymph node dissection plus urinary diversion — SWOG S8710 trial established neoadjuvant platinum as standard (OS HR 0.75); or bladder-preserving trimodal therapy (TURBT + concurrent cisplatin-based chemoradiation, 64.8 Gy in 36 fractions) for selected patients refusing cystectomy or unfit for radical surgery. Adjuvant nivolumab (anti-PD-1) for ypT2+ or N+ disease after neoadjuvant chemo and cystectomy (CheckMate 274: disease-free survival benefit). Locally advanced or metastatic bladder cancer (first-line): enfortumab vedotin (1.25 mg/kg IV days 1, 8 of 21-day cycle) plus pembrolizumab (200 mg IV day 1 every 21 days) — EV-302 trial: median PFS 12.5 vs 6.3 months, median OS 31.5 vs 16.1 months vs gemcitabine-platinum — now the global first-line standard. Cisplatin-eligible patients who decline or do not have access to EV+pembrolizumab: gemcitabine 1000 mg/m2 day 1 and 8 plus cisplatin 70 mg/m2 day 1, every 21 days for 4-6 cycles; maintenance avelumab 800 mg IV every 2 weeks (JAVELIN Bladder 100 trial: OS benefit for non-progressive disease after platinum). Erdafitinib (FGFR3/2 inhibitor) 8 mg orally once daily with uptitration: approved second-line for FGFR3/2-altered metastatic UC (THOR trial: OS benefit vs vinflunine or docetaxel). Sacituzumab govitecan (anti-Trop2 ADC): FDA-approved after platinum and checkpoint inhibitor failure.

Bladder cancer prognosis depends critically on disease stage and response to treatment. Non-muscle-invasive bladder cancer (NMIBC, Ta/T1/Tis) has an overall excellent prognosis — 5-year disease-specific survival exceeds 85-90% for Ta and T1 tumors; however, NMIBC has the highest recurrence rate of any solid tumor (50-70% within 5 years), necessitating lifelong cystoscopic surveillance. High-grade T1 tumors and CIS (carcinoma in situ) carry progression risk to muscle invasion of approximately 30-50% without adequate BCG therapy. BCG intravesical immunotherapy reduces recurrence by 30-40% and progression by 20-30% for high-risk NMIBC compared to TURBT alone. Muscle-invasive bladder cancer (MIBC) has 5-year overall survival of approximately 60-65% after neoadjuvant chemotherapy plus radical cystectomy for T2 disease; T3-T4 disease has 5-year survival of approximately 45-55%; lymph node involvement reduces survival to approximately 25-35%. Pathological complete response (ypT0N0) after neoadjuvant chemotherapy predicts 5-year survival exceeding 80%. Bladder-preserving trimodal therapy (maximal TURBT plus concurrent chemoradiation) achieves comparable outcomes to cystectomy in selected T2 patients, with 5-year OS of approximately 57-66% and bladder preservation in approximately 70-75%. Metastatic urothelial carcinoma treated with enfortumab vedotin plus pembrolizumab (EV-302 trial) achieves unprecedented median overall survival of approximately 31 months — more than double historical platinum-based chemotherapy outcomes. FGFR3-altered metastatic disease responds to erdafitinib with objective responses in approximately 40% after platinum failure. Long-term complications to monitor in survivors include urinary diversion-related metabolic complications, sexual dysfunction, and secondary malignancy risk from prior chemotherapy and radiation. Factors adversely affecting prognosis include high grade, advanced stage, lymphovascular invasion, squamous or glandular differentiation, and poor performance status.

Smoking cessation is the single most impactful preventive strategy, as tobacco causes approximately 50% of bladder cancers; cessation immediately reduces further risk accumulation and risk declines progressively over 15-20 years. Never-smokers should avoid initiating tobacco use. Workers in rubber, dye, leather, and chemical industries at risk of aromatic amine exposure should use proper respiratory and skin protection and undergo periodic urinary surveillance. Adequate daily fluid intake — targeting 2+ litres of urine output — may dilute urinary carcinogens and reduce contact time with the bladder mucosa. Avoiding arsenic-contaminated drinking water is important in endemic regions. Regular cystoscopy surveillance after treatment of bladder cancer is essential for early detection of recurrence, as 50-70% of NMIBC recur within 5 years.

Any single episode of painless visible blood in the urine (macroscopic haematuria) in an adult requires prompt urological evaluation — haematuria should never be attributed to benign causes until bladder cancer and upper tract malignancy have been excluded. Recurrent microscopic haematuria (detected on urinalysis on two or more occasions) also warrants cystoscopy and upper tract imaging. Persistent irritative bladder symptoms — urinary frequency, urgency, and burning — that do not respond to antibiotic treatment may indicate high-grade bladder carcinoma in situ and require cystoscopic evaluation. Patients in high-risk occupational groups (rubber, dye, chemical industries) with any urinary symptom should have a lower threshold for evaluation. Existing bladder cancer patients must adhere to their surveillance cystoscopy schedule — even if completely well — as early recurrence detection allows less aggressive repeat treatment.