Hepatoid Adenocarcinoma of the Lung

Hepatoid adenocarcinoma of the lung (HAL) is an comparatively rare malignant tumor originating from the lung with shorter survival. HAL morphologically and pathologically exhibits hepatocellular carcinoma (HCC)-like characteristics, while its clinical features resemble pulmonary adenocarcinoma. High concentration of alpha-fetoprotein (AFP) is often detected in the serum of HAL patients with no hepatic occupying lesion. Patients with AFP-negative HAL survive a few months longer than those with positive AFP test. HAL is a rare type of carcinoma, so there is a lack of systematic and extensive statistical research. The treatment strategy for HAL is similar to common lung adenocarcinoma. Complete surgical resection and adjuvant chemotherapy are the current major treatments for HAL patients. There are also a few of case reports suggesting that HAL patients may benefit from immunotherapy and targeted therapy. This review focuses on the clinical and pathological features, immunohistochemical staining characteristics, treatment and prognosis of HAL.