Hepatoid adenocarcinoma of the lung metastasizing to the tonsil.

Hepatoid adenocarcinoma (HAC) is a rare tumor that typically originates in gastrointestinal tissue, such as the stomach, but can also occasionally originate in the lung. The majority of HACs express α-fetoprotein (AFP) on tumor cells, and serum AFP can be used as a marker of response to treatment or disease progression. HAC has a poor prognosis, although early diagnosis and aggressive treatment can result in long-term survival. To the best of our knowledge, this is the first reported case of HAC metastasizing to the tonsil. Irradiation using intensity-modulated radiation therapy (IMRT) to 30 Gray (Gy) achieved a significant, and durable tumor response. IMRT can be considered for local control of HAC at other metastatic sites of disease.