Intended learning outcome The student should learn at the end of this lecture principles of CT in bladder cancer.
CTU is a term used to describe high-spatial-resolution imaging of the urinary tract by using contrast material administration, a multidetector CT scanner with thin collimation and imaging in the excretory phase.
Hematuria Patients at increased risk for having upper or lower tract urothelial neoplasms Urinary diversion procedures following cystectomy Hydronephrosis, chronic symptomatic urolithiasis or planning of percutaneous nephrolithotomy (PCNL) Traumatic and iatrogenic uretheral injury, and complex urinary tract infections.
2 Phase- single bolus CTU: - Oral hydration (700 ml of water, 30 min ) - Low dose diuretic (Furosemide): 0.1mg/kg, 1-3 min, before CM - Single bolus of 100 - IV CM - Arterial phase - Nephrographic phase@ 100 sec - Excretory phase @ 12 min (7-15 min)
1.- Ultrasound is widely used. 2.-Using Furosemide there is an improvement in lithiasis diagnosis. Furosemide decrease the urine attenuation value (< 500 HU) *. LithiasisHU Calcium oxalate monohydrate Calcium oxalate dihidrate Cystine Struvite Uric acid 1645+ 238 1417 + 234 711 + 228 666 + 87 409 + 118
Bladder cancer tends to show peak enhancement with the 60- second (portal Phase) scanning delay *. Portal phase CTU offers high accuracy detecting BC: - Sensitivity: 89%–92% in per lesion analysis 95% in per patient analysis - Specificity: 88%– 97% in per lesion analysis 91%–93% in per patient analysis
CTU image review and postprocessing: Using a workstation and/or a picture archiving and communication system (PACS): Creation of multiplanar reformatted images and 3D reconstructed images by using: - Maximum intensity projection techniques (MIP 5-50mm) - Volume-rendering (VR 5-50 mm) -Narrow and wide windows and thin sections with MPR and axial images review (improve the detection rate for tumors smaller than 5 mm)
Homogeneous bladder opacification: Voiding the bladder before examination or mixing bladder contents: patient rolls over supine- prone on the CT table or walks around the CT room. All the excretory system must be included in the exam: Since the urothelium of the entire urinary system is at risk of developing cancer. CTU may allow staging of deeply invasive tumors, detection of metastases and other extra-genitourinary pathology.
Background Is the most common malignancy of the urinary tract. Is a disease of older patients (>65). Represents the 6.6% of the total cancers in men and 2.1% in women, with an estimated male-to-female ratio of 3.8:1*.
Risk factors Cigarrete smoking: Smokers have a two to sixfold increased risk of cancer compared to non-smokers. Occupational exposures: Exposition to aromatic amines (petrochemical, textile, printing industries), hairdressing, firefighting, truck driving, plumbing… Exposures to certains medications: Phenacetin, Cyclophosphamide. Others: Arsenic in drinking water, prior pelvic irradiation and lower urinary tract inflammation (schistosomiasis).
Cell type I.- Epithelial tumors: Urothelial (transitional cell) cancer (90%). Is the most common urinary tract cancer in the United States and Europe. Has a propensity to be multicentric (30-40% ) with synchronous and metachronous bladder and upper tract tumors. Squamous cell (5-8 %) Adenocarcinoma (2%) II.- Non-epithelial tumors: Leiomyosarcomas, lymphoma: Rare
Ta: Non invasive CIS: high- grade flat Urothelial cancer T1: Invade lamina propria T2a and T2b: bladder wall musculature T3a and T3b: perivesical space extension T4: Adyacent organs or pelvic sidewall invasion. GRADE: Grade 1: Well differentiated: papillary/ superficial Grade 2: Poorly differentiated: infiltrative/Invasive
Microscopic or gross hematuria, but only 13- 28% patients with gross hematuria have bladder cancer.
Small filling defects Soft tissue window (W:400, L:40) Wide windows (W:1990, L:362)
67 year-old man. Previous transurethral BC resection. CTU: Asymetric enhancing right wall thickening Cystoscopy: Fybrosis
Flat tumors Bladder lesions located at the bladder base (near prostate and urethra) The most problematic group: Patients have already undergone local treatment for non-invasive bladder tumors.
72 year-old man. CTU: Prostatic hypertrophy and diffuse wall thickening and small polipoid nodule in the posterior bladder wall Cystoscopy: BC in small nodule
75 year-old man. Previous transurethral resection CTU: Small bladder, diffuse wall thickening and small enhancing nodule at bladder dome Cystoscopy: BC