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A4079 - A Nut-ty Case of Lung Cancer
Author Block: E. Levin1, M. E. Dauterive2, C. Brown1; 1Pulmonary and Critical Care, East Carolina University, Brody School of Medicine, Greenville, NC, United States, 2East Carolina University, Brody School of Medicine, Greenville, NC, United States.
Introduction: NUT (Nuclear protein of the testis) carcinoma is a poorly differentiated squamous cell tumor. It was first described in 1991 and called midline carcinoma due to its propensity to occur in midline sites. It is still considered a rare aggressive tumor with poor prognosis. Due to its rarity no standard of care exists for treatment. Case Presentation:A 20 year old white male presents from an outside facility with complaints of cough and dyspnea over a two month period. His associated symptoms include fever and chills. On arrival to our hospital, he had completed two courses of antibiotics for pneumonia with no amelioration in symptoms. He had no significant past medical history and was a marine in basic training. On chest x-ray a left lower opacity was identified and further elicited on chest CT. A bronchoscopy was then performed with biopsy of an endobronchial lesion which identified atypical cells concerning for squamous cell. As no definitive diagnosis was reached, more samples were collected and the tumor was debulked with YAG laser. On further analysis and immunohistochemical staining, the tumor was identified as a NUT carcinoma. In our case, an unusual finding of papillomatosis was noted on histology. Despite aggressive chemotherapy, the patient expired six month after diagnosis. Discussion: NUT carcinoma is a rare entity however may be underdiagnosed due to lack of awareness. It usually involves only a single chromosome translocation t (15;19) (unlike typical squamous carcinomas with complex karyotypes). It is an aggressive tumor with lymph node involvement and metastatic invasion seen frequently at the time of diagnosis. The tumor is also noted to have a rapid progression: initial presentation with a large opacity then within 2-8 weeks progression to complete opacification of the hemithorax. Average survival is 9.5 months. Histopathology is not diagnostic and overlaps with many other poorly differentiated malignant neoplasms. Thus the clinician needs to be aware of this entity as a NUT immunohistochemical tool can confirm the diagnosis (sensitivity 87%, specificity 100%) yet is not often done due to perceived rareness of the disease. Early diagnosis is essential to facilitate further clinical trials for treatment in order to improve outcomes. NUT carcinoma should be included in the differential diagnosis of masses with abnormal clinical presentations, aggressive imaging features, and accelerated clinical (radiographic) courses.