title: Leptomeningeal carcinomatosis in sinonasal undifferentiated carcinoma.
abstract: BACKGROUND
  Sinonasal undifferentiated carcinoma (SNUC) is an uncommon neoplasm characterized by local extension and an aggressive course. Treatment often includes a combination of chemotherapy, radiation therapy, and surgery, although the optimal strategy remains unclear. Here, we present the first reported case of leptomeningeal carcinomatosis from SNUC.
  
  
  RESULTS
  A 28-year-old man with rapidly progressive headaches, congestion, and exophthalmos was found to have a nasal mass. Biopsy revealed sinonasal undifferentiated carcinoma. He had a transient response to chemotherapy followed by a sustained response to concurrent chemoradiation. At the completion of radiation, he developed subtle neurologic findings and MRI revealed diffuse, bulky leptomeningeal spread. He was able to receive only a single fraction of external beam radiation to his spinal axis before his disease rapidly progressed, leading to respiratory failure and death.
  
  
  CONCLUSIONS
  Sinonasal undifferentiated carcinoma can be associated with leptomeningeal carcinomatosis, which can lead to a fulminant clinical course.
authors.affiliation: Division of Medical Oncology, Keck University of Southern California School of Medicine, USC Norris Comprehensive Cancer Center, Los Angeles, California.
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Liu
authors.forename: Naveed
authors.initials: N
authors.lastname: Wagle
authors.forename: Gabriel
authors.initials: G
authors.lastname: Zada
authors.forename: Bonnie
authors.initials: B
authors.lastname: Sun
authors.forename: John
authors.initials: J
authors.lastname: Go
authors.forename: Afshin
authors.initials: A
authors.lastname: Rashtian
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D002277:Carcinoma / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D018450:Disease Progression; D017809:Fatal Outcome; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008444:Maxillary Sinus Neoplasms / Q000473:pathology* / Q000628:therapy; D055756:Meningeal Carcinomatosis / Q000175:diagnosis / Q000532:radiotherapy / Q000556:secondary*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D010255:Paranasal Sinus Neoplasms / Q000473:pathology* / Q000628:therapy; D035583:Rare Diseases; D012131:Respiratory Insufficiency / Q000503:physiopathology
keywords: chemotherapy; leptomeningeal carcinomatosis; radiation; sinonasal undifferentiated carcinoma (SNUC)