Bladder/Urothelial tract

Question 1

benign mimics of malignancy

Answer 1

nephrogenic adenoma

von Brunn nests

cystitis cystica and cystitis glandularis

inverted papilloma

squamous metaplasia

urachal remnants

endometriosis (Mullerianosis)

radiation cystitis

malakoplakia

Question 2

malignant mimics of benign

Answer 2

nested and microcystic urothelial carcinoma (poorly formed nests, deep invasion, focal atypia and mitoses)

Question 3

granulomas

Answer 3

postoperative

BCG therapy

infection: TB, fungal, schistosoma

sarcoid

Question 4

spindle cell lesions

Answer 4

sarcomatoid ca (CK+, p63+)

IMT (ALK1+)
leiomyoma/sarcoma (desmin+)

rhabdomyosarcoma (kids) (myogenin+)

GIST

melanoma

Question 5

nested lesions

Answer 5

nested urothelial carcinoma (poorly formed nests, deep invasion, focal atypia and mitoses)

Brunn nests

paraganglioma (NE markers)

Question 6

bladder adenocarcinoma DDX

Answer 6

urachal adenoca: near dome, no CIS

prostate adenoca: PSA, PSAP

intestinal adenoca (direct spread): mucosal/LP sparing

endometriosis/endocervicosis: benign cytology

metastatic: clinical

Question 7

clear cell adenocarcinoma vs nephrogenic adenoma

Answer 7

CCAc: p53+

NA: PAX8+