Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Etiology | Clinical features | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Positive stains | Negative stains | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Anderson D, Tretiakova M. Lymphoepithelioma-like. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bladderlymphoepithel.html. Accessed April 10th, 2021.
Definition / general
- Rare variant of urothelial carcinoma throughout the urinary tract
- Resembles undifferentiated nasopharyngeal carcinoma but EBV negative (Int J Urol 2007;14:1093, Mod Pathol 2006;19:494)
Essential features
- Rare variant of urothelial carcinoma resembling undifferentiated carcinoma of the nasopharynx
- Composed of sheets of undifferentiated, pleomorphic cells with syncytial appearance, admixed with obscuring inflammatory infiltrate
Terminology
- Also called lymphoepithelial carcinoma but most authors prefer adding "-like" since it is EBV negative, in contrast to the nasopharyngeal tumor
Epidemiology
- Rare (< 50 cases described), first reported in 1991 in bladder
- Incidence 0.4 - 1.3% of all bladder carcinomas but has also been described in upper ureter and renal pelvis (Can Urol Assoc J 2013;7:E590)
- 14 cases of the renal pelvis, including 7 case reports and 2 small case series
- In the bladder is more common in late adulthood (mean age 70 years) with male predominance (Zhou: Genitourinary Pathology, A Volume in the Series - Foundations in Diagnostic Pathology, 2nd Edition, 2015)
- In renal pelvis virtually all reported cases from patients 65 and older
Etiology
- Derived from urothelium, often admixed with conventional urothelial component
- May have similar pathogenesis as high grade invasive urothelial carcinoma (Am J Surg Pathol 2011;35:474)
- Not associated with Epstein-Barr virus (EBV) (Urology 2005;66:1109)
Clinical features
- Painless hematuria (Nat Clin Pract Urol 2007;4:167)
- Common to present with advanced stage (Can Urol Assoc J 2013;7:E590)
Radiology description
- May show enhancing soft tissue mass in the renal pelvis or ureter, involvement of the renal parenchyma or hilar fat
Radiology images
Prognostic factors
- Dispute whether this variant in the urinary tract has more favorable prognosis, especially when pure / predominant (J Urol 1998;159:503, Histopathology 2001;39:106, Urology 2005;66:1109, Mod Pathol 1998;11:1252, Int J Urol 2007;14:1093) or poor prognosis (Virchows Arch 2001;438:552, J Urol 1998;159:779, Am J Surg Pathol 1994;18:466) or whether there is no difference
- Outcome with bladder primary similar to urothelial carcinoma when treated by cystectomy (Mod Pathol 2007;20:828)
- Survival analysis showed no differences with conventional upper urinary tract urothelial carcinoma, as pT classification is the only significant prognostic parameter (Virchows Arch 2017;470:703)
Case reports
- 65 year old man with hematuria (Ann Saudi Med 2009;29:478)
- 65 year old woman with lymphoepithelioma-like carcinoma and squamous component in renal pelvis (Korean J Pathol 2014;48:458)
- 67 year old woman with lower pole renal pelvis tumor infiltrating the perirenal hilar fat (J Urol 2002;167:2127)
- 70 year old Japanese man with lymphoepithelioma-like carcinoma of the renal pelvis (Mod Pathol 1998;11:1252)
- 71 year old man with primary tumor of ureter (Ann Diagn Pathol 2010;14:209)
- 74 year old woman (Arch Pathol Lab Med 2001;125:1383)
- 75 year old woman with ulcerated mass of ureter (Case #267)
- 75 year old women with lymphoepithelioma-like carcinoma in renal pelvis (Can Urol Assoc J 2013;7: E590, Int J Urol 2007;14:851)
Treatment
- There are no specific guidelines regarding management
- In bladder, pure lymphoepithelioma-like carcinoma is reportedly more responsive to chemotherapy
Gross description
- In bladder, relatively small tumor in dome, posterior wall or trigone
Gross images
Microscopic (histologic) description
- Microscopically resembles undifferentiated nasopharyngeal carcinoma
- Pleomorphic, undifferentiated round or spindle cell carcinoma with ill defined borders (Am J Surg Pathol 1994;18:466)
- Arranged in syncytial sheets, nests or individual cells with abundant mixed inflammatory cells often obscuring the neoplastic cells (Am J Surg Pathol 1994;18:466)
- Nonneoplastic cells are a mixture of polyclonal B and T lymphocytes, histiocytes, eosinophils and plasma cells
- May be pure or mixed, onsider recording proportion of variant (Int J Clin Exp Pathol 2009;2:194)
- Surface urothelium may demonstrate carcinoma in situ (CIS)
- Can have focal glandular and clear cell differentiation
Microscopic (histologic) images
Cytology description
- Single cells or mixed with inflammatory cells
- Large tumor cells with high nuclear to cytoplasmic ratio, vesicular chromatin, prominent nucleoli (Diagn Cytopathol 2008;36:600)
Positive stains
Negative stains
- CD45 / LCA (stains lymphocytes, not tumor cells), vimentin, EBV, HPV, TTF1, CD30, AMACR, CDX2, synaptophysin (Virchows Arch 2017;470:703, Am J Surg Pathol 2011;35:474)
Differential diagnosis
- Florid chronic cystitis: no malignant epithelial component, cytokeratin negative
- Lymphoma: no malignant epithelial component, cytokeratin negative; lymphocytes are clonal and LCA positive
- Small cell neuroendocrine carcinoma: molding or crush artifact, no prominent nucleoli and usually no prominent lymphocytic component
- Squamous cell carcinoma, poorly differentiated: a pure squamous lesion with no in situ or invasive urothelial component
- Urothelial carcinoma with prominent lymphocytic reaction: lacks syncytial growth pattern
- Xanthogranulomatous pyelonephritis and other inflammatory lesions: foamy histiocytes; cytokeratin negative
Board review style question #1
Which statement about lymphoepithelioma-like carcinoma of the urinary tract is false:
- Cytokeratin positive
- Derived from the kidney parenchyma
- GATA3 is expressed
- Not associated with Epstein-Barr Virus in contrast to nasopharyngeal carcinoma.
Board review style answer #1
B. The epithelial cells are thought to derive from the urothelium. They are seen in nests and syncytial sheets in a dense inflammatory background which can obscure visualization of the tumor cells.
Reference: Lymphoepithelioma-like carcinoma
Comment Here
Reference: Lymphoepithelioma-like carcinoma
Comment Here