PMID- 31768625 OWN - NLM STAT- MEDLINE DCOM- 20200330 LR - 20220218 IS - 1432-2307 (Electronic) IS - 0945-6317 (Print) IS - 0945-6317 (Linking) VI - 476 IP - 3 DP - 2020 Mar TI - Utility of FOS as diagnostic marker for osteoid osteoma and osteoblastoma. PG - 455-463 LID - 10.1007/s00428-019-02684-9 [doi] AB - Osteoid osteoma and osteoblastoma are bone-forming tumors shown to harbor FOS (87%) and FOSB (3%) rearrangements. The aim was to evaluate the immunohistochemical expression of FOS and FOSB in these tumors in comparison to other bone tumors, to evaluate the influence of decalcification, and to correlate immunohistochemical findings with the underlying genetic alteration using fluorescence in situ hybridization (FISH). Immunohistochemistry using whole sections was performed on osteoid osteoma (n=23), osteoblastoma (n=22), osteoblastoma-like osteosarcoma (n=3), reactive (n=3), and proliferative (n=11) bone lesions. Immunoreactivity in giant cell tumor of bone (n=74), aneurysmal bone cyst (n=6), chondromyxoid fibroma (n=20), osteosarcoma (n=85), chondroblastoma (n=17), and clear cell chondrosarcoma (n=20) was assessed using tissue micro arrays. Strong nuclear expression of FOS in > 50% of the tumor cells was observed in all osteoid osteomas (22/22), in 57% of osteoblastomas (12/21) and in 3/197 control cases. FOS immunoreactivity disappeared after > 3 days decalcification. FOS rearrangements were present in 94% of osteoid osteomas and osteoblastomas, with a concordance of 86% between FISH and immunohistochemistry. Two osteoblastomas (5%) were positive for FOSB, as opposed to 8/177 control cases. Additional FISH revealed no FOSB rearrangements in these cases. To conclude, in short decalcified biopsies, FOS immunohistochemistry can be used to diagnose osteoid osteoma and osteoblastoma, as overexpression is seen in the majority, being rare in their mimics. FOS immunohistochemistry should not be used after long decalcification. Moreover, low level of focal expression found in other lesions and tissues might cause diagnostic problems, in which case FISH could be employed. FAU - Lam, Suk Wai AU - Lam SW AD - Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands. FAU - Cleven, Arjen H G AU - Cleven AHG AD - Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands. FAU - Kroon, Herman M AU - Kroon HM AD - Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands. FAU - Briaire-de Bruijn, Inge H AU - Briaire-de Bruijn IH AD - Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands. FAU - Szuhai, Karoly AU - Szuhai K AD - Department of Cell and Chemical Biology, Leiden University Medical Center, Einthovenweg 20, 2333, ZC, Leiden, The Netherlands. FAU - Bovee, Judith V M G AU - Bovee JVMG AUID- ORCID: 0000-0003-1155-0481 AD - Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands. j.v.m.g.bovee@lumc.nl. LA - eng PT - Journal Article DEP - 20191125 PL - Germany TA - Virchows Arch JT - Virchows Archiv : an international journal of pathology JID - 9423843 RN - 0 (Biomarkers, Tumor) RN - 0 (FOS protein, human) RN - 0 (FOSB protein, human) RN - 0 (Proto-Oncogene Proteins c-fos) SB - IM MH - Adolescent MH - Adult MH - Biomarkers, Tumor/*analysis MH - Bone Neoplasms/*diagnosis MH - Child MH - Child, Preschool MH - Female MH - Humans MH - Male MH - Middle Aged MH - Osteoblastoma/*diagnosis MH - Osteoma, Osteoid/*diagnosis MH - Proto-Oncogene Proteins c-fos/*analysis/biosynthesis MH - Young Adult PMC - PMC7085481 OTO - NOTNLM OT - Bone tumors OT - FOS OT - Fluorescence in situ hybridization OT - Immunohistochemistry OT - Osteoblastoma OT - Osteoid osteoma EDAT- 2019/11/27 06:00 MHDA- 2020/03/31 06:00 PMCR- 2019/11/25 CRDT- 2019/11/27 06:00 PHST- 2019/08/01 00:00 [received] PHST- 2019/09/30 00:00 [accepted] PHST- 2019/09/24 00:00 [revised] PHST- 2019/11/27 06:00 [pubmed] PHST- 2020/03/31 06:00 [medline] PHST- 2019/11/27 06:00 [entrez] PHST- 2019/11/25 00:00 [pmc-release] AID - 10.1007/s00428-019-02684-9 [pii] AID - 2684 [pii] AID - 10.1007/s00428-019-02684-9 [doi] PST - ppublish SO - Virchows Arch. 2020 Mar;476(3):455-463. doi: 10.1007/s00428-019-02684-9. Epub 2019 Nov 25.