histopathology of bladder and urethra.pptx

Histopathology of bladder and urethra.

1. HISTOPHATHOLOGY OF THE BLADDER AND URETHRA

2. URINARY BLADDER Hollow muscular elastic organ that sits on the pelvic floor posterior to the pubic symphysis and stores and expel urine. Males: anterior to rectum Females: just anterior to the vagina and uterus

3. URINARY BLADDER If full: bladder is spherical and extends into abdominal cavity and holds about 500 ml of urine. If empty: bladder lies entirely within pelvis with shape like upside-down pyramid. Urine exits via the urethra Trigone is inside area between ureters and urethra.

4. BLADDER HISTOLOGIC DESCRIPTION 4 layers from inside out: urothelium, lamina propria, muscularis propria, serosa / adventitia. Micrograph showing layers of bladder: urothelium, lamina propria and muscularis propria .

5. UROTHELIUM Urothelium : Three layers of cells. Umbrella or apical cells been the superficial layer. Formerly called transitional epithelium. Pyramid shaped, large and ovoid and it is a binucleated cells.

6. UROTHELIUM SUPERFICIAL CELLS Surface outline often overlapping two or more of the underlying cells. Superficial cytoplasm is not clearly define its more intensely stained than the rest of the cytoplasm. Luminal surface of the cells appears thickened and more densely stained. Form an impermeable barrier and tight junctions between the cells.

7. UROTHELIUM INTERMEDIATE CELLS Multicell layering, depending on the stage of distension. Cuboidal to low columnar with well-defined borders. Uninucleated cells with ovoid nuclei.

8. UROTHRLIUM BASAL CELLS Single layer in contact with basal lamina. Mononucleated with cuboidal cells. Cylindrical, can be flat when bladder wall is stretched some have longitudinal nuclear grooves.

9. The micrograph shows umbrella shaped cells with abundant apical cells. The basal cells are cuboidal and form a single layer. The lamina propria is rich in capillaries.

10. LAMINA PROPRIA Dense connective tissue containing a rich vascular network, lymphatic channels, sensory nerve endings, elastic fibers and adipose tissue . Thickness varies with the degree of expansion and is generally thinner in the areas of the trigone and bladder neck.

11. I rregularly smooth muscle fibers . They have a smaller diameter than muscularis propria .

12. Layer under the urothelium, predominantly consisting of loose connective tissue and nerves.

13. MUSCULARIS PROPRIA 3 layers: inner and outer longitudinal layers and a central circular layer. Layers are distinct near bladder neck, elsewhere it is not clearly define. Bladder's body has a higher smooth muscle content compared with the trigone.

14. Micrograph showing normal bladder histology, with muscularis propria; organized, thick bundle of muscle (lower right).

15. SEROSA / ADVENTITIA Thin connective tissue layer covering the bladder dome and continuous with the peritoneal layer of the abdominal wall. Contains blood vessels of various sizes. Adventitia, an outermost layer of loose connective tissue in areas where there is no serosa.

16. BLADDER PATHOLOGY

17. Urothelial proliferation of uncertain malignant potential. Thickened urothelium is arranged into narrow undulating mucosal folds.

18. Papillary or polypoid cystitis. Broad-based polypoid excrescences with stromal edema and fibrosis or thin papillae without secondary branching characterize polypoid cystitis, which is a benign reactive process.

19. P lasmacytoid urothelial carcinoma. Discohesive individual cells, with eccentric nuclei and abundant eosinophilic cytoplasm, characterize plasmacytoid carcinoma.

20. Most cases exhibit a variable percentage of cells with cytoplasmic vacuoles, with or without intracellular mucin. The absence of extracellular mucin distinguishes plasmacytoid urothelial carcinoma from mucinous adenocarcinoma with signet-ring cell features.

21. Mucinous adenocarcinoma with signet-ring features. The abundant extracellular mucin is characteristic of mucinous adenocarcinoma, which may have a predominance of signet-ring cells and or other patterns of admixed mucinous carcinoma.

22. Nested urothelial carcinoma.

23. Micropapillary urothelial carcinoma. Multiple small clusters of neoplastic urothelial cells in the same lacunar space is a reliable feature of this subtype and is often associated with lacunar spaces.

24. THE URETHRA Smooth muscle with inner mucosa Changes from transitional through stages to stratified squamous near end. Drains urine out of the bladder and body Male: about 20 cm (8) long Female: 3-4 cm (1.5) long Short length is why females have more urinary tract infections than males - ascending bacteria from stool contamination.

25. MALE URETHRA Measures 15 - 20 cm in length. Urethral sphincter surrounds the urethra. Extends from the bladder neck to the inferior fascia of the urogenital diaphragm. Controls urination and discharge of semen into urethra. Composed of smooth and striated muscle. Divided into prostatic, membranous and penile urethra.

26. PROSTATIC URETHRA Extends from the bladder neck through the prostate gland (3 - 4 cm) and lined by urothelium. Ejaculatory ducts enter at the posterior wall and most prostatic ducts empty into the posterior and lateral walls. Verumontanum is posterior to the mid prostatic urethra into which the ejaculatory ducts empty and subsequently join with the prostatic urethra.

27. The prostatic urethra has an undulated multilayered epithelium with a large empty lumen.

28. MEMBRANOUS URETHRA Extends from the apex of the prostate to the bulb of the penis 1 cm. Lined by stratified pseudostratified columnar epithelium similar to urothelium but lacking umbrella cells. Passes through the urogenital diaphragm as it enters the perineum. Surrounded by external voluntary sphincter formed by skeletal muscle of the urogenital diaphragm.

29. PENILE (SPONGY) URETHRA Extends through the penis to the urethral meatus opening in the glans (15 cm). Surrounded by the corpus spongiosum Bulbourethral (Cowper) glands.

30. The penile urethra has an undulated multilayered epithelium with a large empty lumen. It is surrounded by corpus spongiosum with prominent anastomosing vessels .

31. Divided into 3 regions. Bulbar urethra: spans the bulb of the penis, lined by stratified or pseudostratified columnar epithelium. Pendulous urethra: spans the pendulous penis (shaft), lined by stratified or pseudostratified columnar epithelium. Fossa navicularis: dilated portion in the glans, lined by nonkeratinizing squamous epithelium.

32. FEMALE URETRA The female urethra is short 2.5 to 4 cm long and empties at the vulva 2–3 cm posterior to the clitoris. The external sphincter muscle is located at the proximal portion of the urethra.

33. HISTOLOGY OF THE FEMALE URETHRA Epithelium The lumen of the proximal female urethra is lined with urothelium. In the middle is columnar epithelium, and the distal urethra is lined with stratified squamous epithelium.

34. Lamina propria and muscularis The lamina propria is rich in blood vessel. Especially in the distal urethra, numerous glands are located in the lamina propria. The tunica muscularis consists of smooth and striated muscles that build up the urinary bladder's sphincter.

35. MALE AND FEMALE URETHRA

36. URETHRA PATHOLOGY

37. Male penile urethra, squamous cell carcinoma in situ within periurethral glands.

38. Male penile urethra, HPV+ high risk ISH in squamous cell carcinoma in situ within periurethral glands.

39. Non-invasive high grade urothelial carcinoma in a female . Invasive high grade urothelial carcinoma in a female .

40. Primary urethral squamous cell carcinoma with necrosis and keratinization.

41. Polypoid mass is lined by normal appearing urothelium and composed of urethritis cystica and glandularis embedded in a dense fibrous stroma

42. The glands of the urethritis cystica and glandularis are lined by columnar epithelial cells. With pale to eosinophilic cytoplasm and inconspicuous nucleoli. Eosinophilic contents are present in the glandular lumens.