Case Series of SMARCA4-Deficient Undifferentiated Esophageal Carcinoma.

Undifferentiated esophageal carcinomas (UEC) are rare, with aggressive behavior and a dismal prognosis. An extremely rare subset is the SMARCA4-deficient UEC, which has only been reported in 14 cases to date. We present two cases of male patients (39- and 64-year-old) with SMARCA4-deficient UEC. Both patients had evidence of metastatic disease on presentation, progressed rapidly, and passed away within three months from the presentation. We aim to raise awareness of this underreported disease and contribute to the exploration of the possible underlying pathology and risk factors.