Ependymomas of the central nervous system and adult extra-axial ependymomas are morphologically and immunohistochemically distinct - A comparative study with assessment of ovarian carcinomas for expression of glial fibrillary acidic protein Journal Article

  

Authors:	Idowu, M. O.; Rosenblum, M. K.; Wei, X. J.; Edgar, M. A.; Soslow, R. A.
Article Title:	Ependymomas of the central nervous system and adult extra-axial ependymomas are morphologically and immunohistochemically distinct - A comparative study with assessment of ovarian carcinomas for expression of glial fibrillary acidic protein
Abstract:	Extra-axial ependymomas are very rare but have been reported in the ovary, broad ligament, sacrococcygeal region, lung, and mediastinum. The histogenesis is obscure, and a thorough immunohistochemical analysis is lacking. We reviewed the morphologic and immunohistochemical features of 5 extra-axial ependymomas occurring in adults, 1 arising in an infantile sacrococcygeal teratoma, and a control group of 10 central nervous system (CNS) ependymomas in adults. All cases were evaluated for expression of epithelial membrane antigen, estrogen receptor (ER), progesterone receptor (PR), WT1, CD99, CK18, AE1:3, CAM 5.2, 34βE12, CK7, CK20, synaptophysin, chromogranin, and glial fibrillary acidic protein (GFAP) using formalin-fixed, paraffin-embedded tissue. One hundred twelve ovarian carcinomas in 3 tissue microarrays were also studied with GFAP. The adult extra-axial cases demonstrated more architectural variability than the CNS cases. We observed that both the CNS and adult extra-axial ependymomas expressed GFAP diffusely, whereas only 9 stage III, high-grade ovarian serous papillary carcinomas stained with GFAP (2 strongly and diffusely and 7 exhibiting focally weak expression). There were significant immunophenotypic differences between adult extra-axial and CNS ependymomas, with extra-axial cases preferentially expressing 34βE12 (60% vs. 0%), CK18 (100% vs. 20%), CAM 5.2 (60% vs. 10%), CK7 (80% vs. 10%), ER (100% vs. 10%), and PR (80% vs. 20%). Two spinal cord ependymomas expressed CK18, 1 expressed CK7, and 1 expressed CAM 5.2. CNS ependymomas more frequently expressed CD99 (100% vs. 20%). The following stains were not differentially expressed: epithelial membrane antigen (expressed in 2 of 15 cases, including both extra-axial and CNS ependymomas), synaptophysin (1/15), chromogranin (0/15), WT1 (8/15), AE1:3 (10/15), and CK20 (0/15). The ependymal elements of the sacrococcygeal tumor failed to express 34βE12, CK18, CAM 5.2, and CK7, like most CNS ependymomas. The morphologic and immunophenotypic differences between extra-axial and CNS ependymomas suggest that they derive from distinct precursors and/or differentiate along distinct pathways. The differential diagnosis of extra-axial ependymomas is extensive, and GFAP expression in primary ovarian serous carcinomas, although rare, could theoretically contribute to diagnostic difficulties. ER and PR expression in extra-axial ependymomas may provide targets for hormonal therapy. © 2008 Lippincott Williams & Wilkins, Inc.
Keywords:	immunohistochemistry; adolescent; adult; clinical article; controlled study; preschool child; protein expression; middle aged; clinical feature; histopathology; anamnesis; paclitaxel; antineoplastic agent; neoplasm staging; salpingooophorectomy; adenocarcinoma; ovarian neoplasms; carboplatin; multiple cycle treatment; neoplasm recurrence, local; lung non small cell cancer; differential diagnosis; tumor markers, biological; glial fibrillary acidic protein; combination chemotherapy; cyclophosphamide; morphology; central nervous system neoplasms; ovary; immunoenzyme techniques; infant; ovary carcinoma; ependymoma; teratoma; wt1 protein; cytokeratin; estrogen receptor; progesterone receptor; thymoma; chromogranin; abdominal hysterectomy; epithelial membrane antigen; synaptophysin; antibody labeling; broad ligament
Journal Title:	American Journal of Surgical Pathology
Volume:	32
Issue:	5
ISSN:	0147-5185
Publisher:	Lippincott Williams & Wilkins
Date Published:	2008-05-01
Start Page:	710
End Page:	718
Language:	English
DOI:	10.1097/PAS.0b013e318159a2b4
PUBMED:	18360284
PROVIDER:	scopus
DOI/URL:	http://www.scopus.com/inward/record.url?eid=2-s2.0-42649135137&partnerID=40&md5=bb016cfeb844108cb9a592f5f5e5160f
Notes:	--- - "Cited By (since 1996): 7" - "Export Date: 17 November 2011" - "CODEN: AJSPD" - "Source: Scopus"

https://synapse.mskcc.org/synapse/works/has_related_data_chk/14613