The recently described SWI/SNF complex-deficient sinonasal carcinoma (SMARCB1 & SMARCA4) may exhibit a yolk sac-like morphology. Tumors with similar features (yolk sac-like histology combined with the immunohistochemical loss of SMARCB1/INI1 and/or SMARCA4/BRG1) have also been described in other sites, such as the female genital tract. In this study, we immunohistochemically assessed SMARCB1/INI1 and SMARCA4/BRG1 expression to evaluate if these proteins could be involved in the pathogenesis of testicular yolk sac tumors of postpubertal type (YSTpt). Specifically, we analyzed a retrospective case series comprising pure YSTpt and mixed germ cell tumors of the testis (GCTT) with YSTpt components. In the present study, no testicular YSTpt showed loss of SMARCB1/INI1 (0/24, 0%) or SMARCA4/BRG1 (0/24, 0%). However, testicular choriocarcinoma (CHC) and isolated syncytiotrophoblast cells (iSTCs) demonstrated abnormal staining patterns for SMARCA4/BRG1 [CHC: 4/4 (100%); iSTCs: 12/12 (100%), respectively], including focal or diffuse loss of expression in a subset of cases. The results of our study suggest that functional loss of SMARCA4/BRG1 represents a recurrent event that may be relevant for the pathogenesis of a subset of testicular CHC.
Yolk sac tumor of postpubertal-type does not exhibit immunohistochemical loss of SMARCB1/INI1 and SMARCA4/BRG1…but choriocarcinoma? / Ricci, C.; Ambrosi, F.; Franceschini, T.; Giunchi, F.; Franchini, E.; Massari, F.; Mollica, V.; Bianchi, F. M.; Colecchia, M.; Acosta, A. M.; Fiorentino, M.. - In: PATHOLOGY RESEARCH AND PRACTICE. - ISSN 0344-0338. - 241:(2023). [10.1016/j.prp.2022.154269]
Yolk sac tumor of postpubertal-type does not exhibit immunohistochemical loss of SMARCB1/INI1 and SMARCA4/BRG1…but choriocarcinoma?
Colecchia M.;
2023-01-01
Abstract
The recently described SWI/SNF complex-deficient sinonasal carcinoma (SMARCB1 & SMARCA4) may exhibit a yolk sac-like morphology. Tumors with similar features (yolk sac-like histology combined with the immunohistochemical loss of SMARCB1/INI1 and/or SMARCA4/BRG1) have also been described in other sites, such as the female genital tract. In this study, we immunohistochemically assessed SMARCB1/INI1 and SMARCA4/BRG1 expression to evaluate if these proteins could be involved in the pathogenesis of testicular yolk sac tumors of postpubertal type (YSTpt). Specifically, we analyzed a retrospective case series comprising pure YSTpt and mixed germ cell tumors of the testis (GCTT) with YSTpt components. In the present study, no testicular YSTpt showed loss of SMARCB1/INI1 (0/24, 0%) or SMARCA4/BRG1 (0/24, 0%). However, testicular choriocarcinoma (CHC) and isolated syncytiotrophoblast cells (iSTCs) demonstrated abnormal staining patterns for SMARCA4/BRG1 [CHC: 4/4 (100%); iSTCs: 12/12 (100%), respectively], including focal or diffuse loss of expression in a subset of cases. The results of our study suggest that functional loss of SMARCA4/BRG1 represents a recurrent event that may be relevant for the pathogenesis of a subset of testicular CHC.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
