Teratocarcinosarcoma (TCS) is an extremely rare and aggressive malignant neoplasm with uncertain
histogenesis. Overall, fewer than 100 cases of TCS have been reported in English research. This article
reports a case of a 19-year-old male patient who was cured of nasal-type natural killer/T-cell (NK/Tcell) lymphoma through concurrent chemoradiotherapy (CCRT). After 13 years, at the age of 32, he
developed sinonasal teratocarcinosarcoma (SNTCS) and subsequently underwent endoscopic sinus
surgery and CCRT. The patient tolerated the treatment well, and symptoms were resolved. Tumor
recurrence was not observed during 12-month posttherapy follow-up endoscopy and magnetic
resonance imaging. This is the first reported case of SNTCS development after CCRT for nasal-type
NK/T-cell lymphoma. This report highlights the importance of considering the effects of CCRT on
SNTCS development and expands the spectrum of reported radiation-induced malignancies in the
sinonasal tract.
