title: The World Health Organization 2016 classification of testicular non-germ cell tumours: a review and update from the International Society of Urological Pathology Testis Consultation Panel.
abstract: The World Health Organization (WHO) released a new tumour classification for the genitourinary system in early 2016 after consensus by pathologists with expertise in these organs. It utilized the framework of the 2004 classification, and incorporated the most up-to-date information concerning these tumours. In testicular tumours, the majority of the changes occurred in the nomenclature and classification of germ cell tumours; however, several modifications were also made for non-germ cell tumours. Among sex cord-stromal tumours, sclerosing Sertoli cell tumour (SCT) is no longer recognized as a separate entity but as a morphological variant of SCT not otherwise specified (NOS), as CTNNB1 gene mutations have been noted in both neoplasms but not in the other forms of SCT. Similarly, the lipid cell variant is not separately classified, but is considered to be a morphological variant of SCT NOS. Large-cell calcifying SCT is recognized as a distinct entity that occurs either sporadically or in association with Carney complex, with the latter patients having a distinct germline PRKAR1A gene mutation. Intratubular large-cell hyalinizing Sertoli cell neoplasia is also accepted as a separate entity linked with Peutz-Jeghers syndrome. The subcategories of 'mixed' and 'incompletely differentiated' forms of sex cord/gonadal stromal tumours have been replaced by 'mixed and unclassified sex cord-stromal tumours'. New entities introduced in the latest WHO revision include: myoid gonadal stromal tumour and 'undifferentiated gonadal tissue', a putative precursor lesion of gonadoblastoma, whereas juvenile xanthogranuloma and haemangioma are included in the miscellaneous category of tumours.
authors: Department of Pathology and Laboratory Medicine, Indiana University, Indianapolis, IN, USA.
authors: Muhammad T
authors: MT
authors: Idrees
authors: Department of Pathology and Laboratory Medicine, Indiana University, Indianapolis, IN, USA.
authors: Thomas M
authors: TM
authors: Ulbright
authors: Pathology Department, Massachusetts General Hospital, Boston, MA, USA.
authors: Esther
authors: E
authors: Oliva
authors: Pathology Department, Massachusetts General Hospital, Boston, MA, USA.
authors: Robert H
authors: RH
authors: Young
authors: Department of Pathology, Università Politecnica delle Marche, Ancona, Italy.
authors: Rodolfo
authors: R
authors: Montironi
authors: Department of Pathology, Karolinska University Hospital, Stockholm, Sweden.
authors: Lars
authors: L
authors: Egevad
authors: Department of Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK.
authors: Daniel
authors: D
authors: Berney
authors: Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
authors: John R
authors: JR
authors: Srigley
authors: Department of Pathology, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors: Jonathan I
authors: JI
authors: Epstein
authors: Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
authors: Satish K
authors: SK
authors: Tickoo
mesh_terms: D006801:Humans; D008297:Male; D018312:Sex Cord-Gonadal Stromal Tumors / Q000145:classification*; D013736:Testicular Neoplasms / Q000145:classification*; D014944:World Health Organization
keywords: ISUP; World Health Organization 2016 Classification; non-germ cell tumours; testicular tumours