ARID1B and ovarian carcinoma: Inactivation of the SWI/SNF complex through alterations of core subunits (SMARCA4, SMARCB1, and ARID1B) has been strongly associated with dedifferentiated and undifferentiated endometrial and ovarian carcinomas (DDC/UDC) but is also reported in dedifferentiated and undifferentiated malignancies from many different tissues, including gastrointestinal, hepatobiliary, genitourinary, head and neck, thoracic, mammary, and neurologic [3,4,5,6,7,8,9,10].