The Gross Appearance of a NUT Midline Carcinoma.

The NUT midline carcinoma (NMC) is a recently described and highly aggressive tumor that usually involves the head and neck and anterior mediastinum. Most patients with NMC present with metastases and are often treated with neoadjuvant chemotherapy and/or radiation therapy. As a consequence, surgical specimens are often piecemeal excisions demonstrating treatment effect. In this report, we provide what is to the best of our knowledge the first complete gross description of NMC resected in toto and without prior treatment. The patient in this case underwent a pneumonectomy for a lung mass with curative intent. On gross examination, the tumor was found to be arising from the mediastinum with a smooth border, and demonstrated only minimal invasion of the surrounding structures. However, lymphovascular invasion was present throughout and there was extensive involvement of surrounding lymph nodes. The gross appearance of the tumor in this case reaffirms that NMC is an aggressive malignancy that usually metastasizes before it invades locally.