Follow-up strategy based on event dynamics for stage II nasopharyngeal carcinoma.PURPOSE
 To investigate the follow-up strategy of stage II NPC based on event dynamics.


 Stage II NPC patients were retrospectively assessed from January 2007 to December 2014 at Guangxi Medical University Cancer Hospital.  Event dynamics for patterns of recurrence and metastasis were calculated based on the hazard rates.


 A total of 251 patients were included.  After treatment, 10 (4.0%) patients developed recurrence and 6 (2.4%) patients developed metastasis.  The hazard rate curve of recurrence showed a bimodal recurrence pattern.  The maximum hazard rates were 0.048 and 0.072 at the intervals of 36-42 and 90-96 months, respectively.  The maximum hazard rate was 0.036 at the interval of 48-54 months in the hazard rate curve of metastasis.


 CONCLUSIONS
 Follow-up strategies of stage II NPC should be performed based on currently recommended guidelines. 
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