S4396 Double Trouble: A Rare Esophageal Cancer

Introduction: Adenosquamous carcinoma (ASC) of the esophagus is a rare type of esophageal cancer that contains both adenocarcinoma and squamous cell carcinoma elements. ASC of the esophagus has a poorer prognosis and a higher rate of lymph node and distant metastasis compared to adenocarcinoma or squamous cell carcinoma alone. We present a case of ASC of the esophagus in a 61-year-old man. Case Description/Methods: A 61-year-old man with a past medical history of intellectual disability and chronic cigarette smoker presented to the emergency department with 2-month history of vomiting after meals and 27 pounds weight loss. Computed tomography abdomen and pelvis revealed a 1.9 cm thickening of the gastroesophageal junction, suggesting possible malignancy. Upper endoscopy showed near complete obstruction at the lower esophagus at 39 cm with friable mucosa concerning malignancy, which was biopsied. Pathology showed moderately differentiated invasive carcinoma with both gland formation and non-keratinizing squamous differentiation, which is most consistent with adenosquamous carcinoma. A gastrojejunostomy tube was placed for nutrition. The patient was initially treated with Carboplatin and Paclitaxel-based neoadjuvant chemoradiation with curative intent. However, he developed metastatic disease and declined further treatment with palliative chemotherapy and immunotherapy. The patient's family decided for him to be made comfort care. Discussion: ASC of the esophagus is a rare type of esophageal cancer, accounting for about 1% of all esophageal carcinomas. A multidisciplinary approach is required for treatment. Its prognosis is difficult to ascertain given its low incidence, which is reflected in current literature with conflicting data. ASC has the potential to have worse prognosis, with some studies suggesting lower mean survival time compared to esophageal squamous cell carcinoma or esophageal adenocarcinoma alone. Prompt diagnosis of this cancer is essential in guiding neoadjuvant chemotherapy, radiation, surgical resection, and potential immunotherapy to augment patients' prognosis.