Hepatoid Adenocarcinoma of the Lung: A Case Report on a Rare Medical Condition.

We describe a case of an 82-year-old man who initially presented with back pain in the thoracic region and, on imaging, was found to have a right lower lobe lung nodule and a soft tissue mass eroding the posterior aspect of the right-sided ninth rib. Biopsy of this soft-tissue mass initially raised concern for metastatic HCC, but the patient was later found to have hepatoid adenocarcinoma of the lung. The patient was started on immunotherapy and a chemotherapy regimen, but unfortunately died within six months of diagnosis, highlighting the aggressive nature and course of the disease.