Retrograde Analysis of Clinical Characteristics of Bone Metastasis in 1,031 Cases of Preliminarily Diagnosed Nasopharyngeal Carcinoma

Purpose: To explore the clinical characteristics of bone metastasis (BM) in a large sample of preliminarilydiagnosed nasopharyngeal carcinomas (NPCs).
Methods: The sample consisted of 1,031 patients diagnosed withNPC at first visitg clinics between October 1989 and June 2012. Several parameters including metastasis locus,T/N staging, diagnosis, therapy and prognosis of BM were analyzed retrospectively.
Results: In 70 patients whohad been preliminarily diagnosed with BM, the incidence of BM in N0, N1, N2 and N3 stage was 5.7%, 17.2%,50.2%, and 25.7%, respectively, while the incidence in T0, T1, T2 and T3 stage was 0%, 23.8%, 47.6% and 28.6%respectively. BM occurred in most common in vertebral column, rib, sternum, ilium and femur. Positive rate ofEpstein-Barr virus antibody was 77.6%. The median survival time was 12 months.
Conclusion: The incidenceof BM in NPC preliminarily diagnosed is about 7% and it is related to N classification but not T classification.