Nasopharyngeal carcinoma in childhood and adolescence: a single institution's experience with treatment modalities during the last 15 years.

Pediatric nasopharyngeal carcinoma (NPC) represents a locally advanced undifferentiated tumor with widely varying epidemiological features and with a high cure rate when combined modality treatment is provided. Both local and systemic treatment is necessary, and additional treatment with biologic modifiers seems promising. In this study, clinical experience and therapeutic results of 10 children with newly diagnosed NPC, treated in a single pediatric hematology/oncology institution in Athens over a period of 15 years, are analyzed. Results from Greece on NPC in young patients are reported for the first time. Ten patients (6 male, 4 female) 7-14 years old (median = 12.5) with a nasopharyngeal tumor were retrospectively evaluated. Disease extent was staged according to the TNM system. EBV-DNA, EBERs, and LMP-1 from paraffin-embedded tissues were studied in 8 patients. All patients received both local and systemic treatment. All cases were classified as type WHO-3. The presence of EBV-DNA and expression of EBER 1-2 mRNAs was demonstrated in the 8 tumors examined, while LMP-1 protein was expressed in 4/8 of the studied cases. Disease stage was III in 4 and IV in 6 patients. Time from the onset of symptoms to diagnosis ranged from 4 to 24 weeks (mean 8 weeks). All patients received preradiation chemotherapy and radiotherapy, and 5/10 received postradiation chemotherapy due to either resistant or advanced disease. In 9/10 patients, complete locoregional control was achieved. In addition to chemotherapy and radiotherapy the latest patient of this series was treated with recombinant IFN-beta (10(5) IU/Kg i.v. 3 times a week) for 6 months and at 18 months remains in continuous complete remission. One patient was lost to follow-up 3 years after cessation of treatment while remaining in complete remission. Of the remaining 9 patients, 7 are alive for a median follow-up of 54 months (range 18-186); 5/7 are free of disease, and 2/7 are with disease but stable. The median time for first relapse was 17 months. The data confirm the good results of combined chemo-radiotherapy treatment for high-risk NPC in young patients. The documented EBV latency underlying this tumor, which possibly critically mediates its pathogenesis, justifies the use of biological modifiers with antiviral and immunoregulatory activity, like the IFNs, which may offer better therapeutic results in the future.