Radiological, pathological and DNA remission in recurrent metastatic nasopharyngeal carcinoma

Background: Circulating plasma Epstein Barr Virus DNA (EBV-DNA) is a sensitive and specific marker of nasopharyngeal carcinoma (NPC). The mainstay of treatment of metastatic NPC is systemic chemotherapy and resection for solitary metastasis. Despite high response rate to chemotherapy, complete remission is uncommonly seen. Case Presentation: We report a case of recurrent metastatic NPC in a 43-year-old man, who achieved complete remission three times with chemotherapy and surgery. Serial plasma EBV-DNA levels were measured during the course of disease. The patient had three episodes of recurrences of NPC manifested as distant metastasis. Both time, rise in the plasma EBV-DNA level preceded detection of recurrences by imaging. Following systemic chemotherapy, he achieved complete remission each time, of which was confirmed by 18-flourodeoxyglucose positron emission tomography and hepatectomy pathology. The plasma EBV-DNA level dropped to zero copy/ml at the time of each remission. Conclusion: This case highlights the high chemosensitivity of NPC by illustrating a rare occurrence of complete response of metastatic NPC to chemotherapy. This case also underscores the usefulness of EBV-DNA as a useful tool in monitoring NPC by its ability to detect early recurrence and excellent correlation with treatment response.