Jiao-jie Lv , Qian-lan Yao , Xue-bing Jiang , Min Ren , Xu Cai , Bo Dai , Yun-yi Kong
{"title":"Primary leptomeningeal melanocytic neoplasms: A clinicopathologic, immunohistochemical, and molecular study of 12 cases","authors":"Jiao-jie Lv , Qian-lan Yao , Xue-bing Jiang , Min Ren , Xu Cai , Bo Dai , Yun-yi Kong","doi":"10.1016/j.humpath.2024.04.014","DOIUrl":null,"url":null,"abstract":"<div><p>This study investigated the clinicopathological, immunohistochemical, and molecular features of primary leptomeningeal melanocytic neoplasms (LMNs). Twelve LMN cases were retrospectively reviewed. We performed Fluorescence <em>in-situ</em> hybridization (including a 4-probe FISH assay with <em>CDKN2A</em> and <em>MYC</em> assay) and Next-Generation sequencing analyses on available cases. Histologically, 2 tumours were classified as melanocytomas (MC), 2 as intermediate-grade melanocytomas (IMC), and 8 as leptomeningeal melanomas (LMM). Two rare cases of LMM were associated with large plaque-like blue nevus. One MC case was associated with Ota. Ten cases (83.3%) showed melanocytic cells with benign features diffusely proliferating within the meninges. The Ki-67 in three categories differed (MC 0–1%, IMC 0–3%, LMM 3–10%). 57.1% of LMM cases (4/7) were positive for FISH. Nine of 10 tumours harboured activating hotspot mutations in <em>GNAQ, GNA11,</em> or <em>PLCB4</em>. Additional mutations of <em>EIF1AX, SF3B1,</em> or <em>BAP1</em> were found in 40%, 30%, and 10% of tumours, respectively. During the follow-up (median = 43 months), 5 LMM patients experienced recurrence and/or metastasis, 3 of them died of the disease and the other 2 are alive with the tumour. Our study is by far the first cohort of LMN cases tested by FISH. In addition to morphological indicators including necrosis and mitotic figures, using a combination of Ki-67 and FISH helps to differentiate between IMC and LMM, especially in LMM cases with less pleomorphic features. <em>SF3B1</em> mutation is first described in 2 cases of plaque-type blue nevus associated with LMM. Patients with <em>SF3B1</em> mutation might be related to poor prognosis in LMN.</p></div>","PeriodicalId":13062,"journal":{"name":"Human pathology","volume":null,"pages":null},"PeriodicalIF":2.7000,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Human pathology","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0046817724000662","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PATHOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigated the clinicopathological, immunohistochemical, and molecular features of primary leptomeningeal melanocytic neoplasms (LMNs). Twelve LMN cases were retrospectively reviewed. We performed Fluorescence in-situ hybridization (including a 4-probe FISH assay with CDKN2A and MYC assay) and Next-Generation sequencing analyses on available cases. Histologically, 2 tumours were classified as melanocytomas (MC), 2 as intermediate-grade melanocytomas (IMC), and 8 as leptomeningeal melanomas (LMM). Two rare cases of LMM were associated with large plaque-like blue nevus. One MC case was associated with Ota. Ten cases (83.3%) showed melanocytic cells with benign features diffusely proliferating within the meninges. The Ki-67 in three categories differed (MC 0–1%, IMC 0–3%, LMM 3–10%). 57.1% of LMM cases (4/7) were positive for FISH. Nine of 10 tumours harboured activating hotspot mutations in GNAQ, GNA11, or PLCB4. Additional mutations of EIF1AX, SF3B1, or BAP1 were found in 40%, 30%, and 10% of tumours, respectively. During the follow-up (median = 43 months), 5 LMM patients experienced recurrence and/or metastasis, 3 of them died of the disease and the other 2 are alive with the tumour. Our study is by far the first cohort of LMN cases tested by FISH. In addition to morphological indicators including necrosis and mitotic figures, using a combination of Ki-67 and FISH helps to differentiate between IMC and LMM, especially in LMM cases with less pleomorphic features. SF3B1 mutation is first described in 2 cases of plaque-type blue nevus associated with LMM. Patients with SF3B1 mutation might be related to poor prognosis in LMN.
期刊介绍:
Human Pathology is designed to bring information of clinicopathologic significance to human disease to the laboratory and clinical physician. It presents information drawn from morphologic and clinical laboratory studies with direct relevance to the understanding of human diseases. Papers published concern morphologic and clinicopathologic observations, reviews of diseases, analyses of problems in pathology, significant collections of case material and advances in concepts or techniques of value in the analysis and diagnosis of disease. Theoretical and experimental pathology and molecular biology pertinent to human disease are included. This critical journal is well illustrated with exceptional reproductions of photomicrographs and microscopic anatomy.