Aim: To highlight the challenges involved in the diagnosis and management of synchronous tumours. A synchronous head and neck lesion brings the attending physician into a quandary, as there is no gold standard for managing such patients. Failure to respond to treatment should provoke physicians into considering other possible diagnoses, as often a secondary lesion may be the hidden culprit. Case report: Herein, we present a case of a synchronous cervical mass: Kimura disease and nasopharyngeal carcinoma in a 48-year-old woman. She was initially treated for Kimura disease based on fine-needle aspiration cytology evidence, and later found out to have a synchronous malignancy in the fossa of Rosenmüller. Failure of Kimura disease to respond to steroid treatment led to a repeated examination, which resulted in the diagnosis of nasopharyngeal carcinoma. The patient was treated with concurrent chemoradiotherapy. Conclusion: Kimura disease, a rare benign head and neck tumour, is treated successfully with steroids. Persistent swelling coupled with treatment failure should alert physicians to repeat patient assessment, as improper disease management leads to severe complications.