TY - JOUR
T1 - Myoid gonadal stromal tumours are characterised by recurrent chromosome-level copy number gains
T2 - molecular assessment of a multi-institutional series
AU - Collins, Katrina
AU - Sholl, Lynette M.
AU - Siegmund, Stephanie
AU - Dickson, Brendan C.
AU - Colecchia, Maurizio
AU - Michalová, Květoslava
AU - Hwang, Michael
AU - Ulbright, Thomas M.
AU - Kao, Chia Sui
AU - van Leenders, Geert J.L.H.
AU - Mehta, Vikas
AU - Trpkov, Kiril
AU - Yilmaz, Asli
AU - Cimadamore, Alessia
AU - Matoso, Andres
AU - Epstein, Jonathan I.
AU - Maclean, Fiona
AU - Comperat, Eva
AU - Anderson, William J.
AU - Fletcher, Christopher D.M.
AU - Acosta, Andrés M.
N1 - Publisher Copyright:
© 2022 John Wiley & Sons Ltd.
PY - 2023/2
Y1 - 2023/2
N2 - Myoid gonadal stromal tumours (MGST) represent a rare type of testicular sex cord-stromal tumour that has recently been recognised as a distinct entity by the World Health Organization (WHO) classification of genitourinary tumours. MGSTs affect adult men and have been reported to behave in an indolent fashion. Histologically, MGSTs are pure spindle cell neoplasms that coexpress SMA and S100 protein. Given that the molecular features of these neoplasms remain largely undescribed, we evaluated a multi-institutional series of MGSTs using DNA and RNA sequencing. This study included 12 tumours from 12 patients aged 28 to 57 years. Tumour sizes ranged from 0.6 to 4.3 cm. Aggressive histologic features, such as vascular invasion, necrosis, invasive growth, and atypical mitoses were invariably absent. Mitotic activity was low, with a median of less than 1 mitosis per 10 high power fields (HPF; maximum: 3 mitoses per 10 HPF). Molecular analyses did not identify recurrent mutations or gene fusions. All cases with interpretable copy number variant data (9/10 cases sequenced successfully) demonstrated a consistent pattern of chromosome arm-level and whole-chromosome-level copy number gains indicative of ploidy shifts, with recurrent gains involving chromosomes 3, 6, 7, 8, 9, 11, 12, 14q, 15q, 17, 18q, 20, and 21q. Similar findings have also been recognised in pure spindle cell and spindle-cell predominant sex cord-stromal tumours without S100 protein expression. MGSTs are characterised by ploidy shifts and may be part of a larger spectrum of spindle cell-predominant sex cord-stromal tumours, including cases without S100 protein expression.
AB - Myoid gonadal stromal tumours (MGST) represent a rare type of testicular sex cord-stromal tumour that has recently been recognised as a distinct entity by the World Health Organization (WHO) classification of genitourinary tumours. MGSTs affect adult men and have been reported to behave in an indolent fashion. Histologically, MGSTs are pure spindle cell neoplasms that coexpress SMA and S100 protein. Given that the molecular features of these neoplasms remain largely undescribed, we evaluated a multi-institutional series of MGSTs using DNA and RNA sequencing. This study included 12 tumours from 12 patients aged 28 to 57 years. Tumour sizes ranged from 0.6 to 4.3 cm. Aggressive histologic features, such as vascular invasion, necrosis, invasive growth, and atypical mitoses were invariably absent. Mitotic activity was low, with a median of less than 1 mitosis per 10 high power fields (HPF; maximum: 3 mitoses per 10 HPF). Molecular analyses did not identify recurrent mutations or gene fusions. All cases with interpretable copy number variant data (9/10 cases sequenced successfully) demonstrated a consistent pattern of chromosome arm-level and whole-chromosome-level copy number gains indicative of ploidy shifts, with recurrent gains involving chromosomes 3, 6, 7, 8, 9, 11, 12, 14q, 15q, 17, 18q, 20, and 21q. Similar findings have also been recognised in pure spindle cell and spindle-cell predominant sex cord-stromal tumours without S100 protein expression. MGSTs are characterised by ploidy shifts and may be part of a larger spectrum of spindle cell-predominant sex cord-stromal tumours, including cases without S100 protein expression.
KW - myoid gonadal stromal tumour
KW - sex cord-stromal tumour
KW - spindle cell tumour
KW - testicular tumour
KW - testis
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U2 - 10.1111/his.14825
DO - 10.1111/his.14825
M3 - Article
C2 - 36226695
AN - SCOPUS:85141430098
SN - 0309-0167
VL - 82
SP - 431
EP - 438
JO - Histopathology
JF - Histopathology
IS - 3
ER -