Differential NF1, p16, and EGFR patterns by interphase cytogenetics (FISH) in malignant peripheral nerve sheath tumor (MPNST) and morphologically similar spindle cell neoplasms.

摘要: Malignant peripheral nerve sheath tumors (MPNSTs) are diagnostically challenging neoplasms for which sensitive and specific immunohistochemical markers lacking. Although limited to date, previous studies have suggested that NF1 (17q), NF2 (22q), p16 (9p), EGFR (7p) alterations may be involved in MPNST tumorigenesis. To determine whether genetic changes differentiate between morphologically similar neoplasms, we assessed these chromosomal regions 22 MPNSTs (9 NF1-associated, 13 sporadic), plexiform neurofibromas, 5 cellular schwannomas, 8 synovial sarcomas, 6 fibrosarcomas, hemangiopericytomas by 2-color FISH. deletions, often the form of monosomy 17, were found (76%). neurofibromas (31%), (17%), fibrosarcomas but not sarcomas or schwannomas. losses encountered more frequently versus other (p < 0.001), as homozygous deletions (45% vs 0%; p amplifications (26% = 0.006), polysomies either chromosomes 7 (53% 12%; 0.003) (50% 4%; 0.001). Hemizygous detected 75% MPNSTs, benign Thus, FISH analysis identifies relatively patterns useful selected cases, differential diagnosis includes low- high-grade MPNST.