Establishing the Natural History and Growth Rate of Ameloblastoma with Implications for Management: Systematic Review and Meta-Analysis

BackgroundAmeloblastoma is the second most common odontogenic tumor, known to be slow-growing, persistent, and locally aggressive. Recent data suggests that ameloblastoma is best treated with wide resection and adequate margins. Following primary excision, bony reconstruction is often necessary for a functional and aesthetically satisfactory outcome, making early diagnosis paramount. Despite earlier diagnosis potentially limiting the extent of resection and reconstruction, an understanding of the growth rate and natural history of ameloblastoma has been notably lacking from the literature.MethodA systematic review of the literature was conducted by reviewing relevant articles from PubMed and Web of Science databases. Each article’s level of evidence was formally appraised according to the Centre of Evidence Based Medicine (CEBM), with data from each utilized in a meta-analysis of growth rates for ameloblastoma.ResultsLiterature regarding the natural history of ameloblastoma is limited since the tumor is immediately acted upon at its initial detection, unless the patient voluntarily refuses a surgical intervention. From the limited data, it is derived that the highest estimated growth rate is associated with solid, multicystic type and the lowest rate with peripheral ameloblastomas. After meta-analysis, the calculated mean specific grow rate is 87.84% per year.ConclusionThe growth rate of ameloblastoma has been demonstrated, offering prognostic and management information, particularly in cases where a delay in management is envisaged.

背景：成釉细胞瘤（ameloblastoma）是第二常见的牙源性肿瘤（odontogenic tumor），以生长缓慢、迁延不愈且具有局部侵袭性为典型特征。现有研究表明，成釉细胞瘤的最优治疗方案为广泛切除术（wide resection）联合安全切缘（adequate margins）。原发灶切除术后，通常需实施骨重建（bony reconstruction）以获得功能与美学俱佳的预后效果，因此早期诊断至关重要。尽管早期诊断可缩小手术及重建的范围，但目前学界对成釉细胞瘤的生长速率与自然病程的认知仍存在显著空白。
方法：本研究通过检索PubMed与Web of Science数据库中的相关文献，开展了一项系统综述。依据循证医学中心（Centre of Evidence Based Medicine, CEBM）的标准，对纳入文献的证据等级进行正式评估，并提取各研究数据用于成釉细胞瘤生长速率的荟萃分析（meta-analysis）。
结果：由于成釉细胞瘤在初次确诊后通常会立即接受干预治疗（除非患者主动拒绝手术干预），相关自然病程的文献较为有限。基于现有有限数据可知，实性多囊型成釉细胞瘤（solid, multicystic type ameloblastoma）的预估生长速率最高，外周型成釉细胞瘤（peripheral ameloblastomas）的生长速率最低。经荟萃分析计算，其平均比生长速率为每年87.84%。
结论：本研究明确了成釉细胞瘤的生长速率，可为其预后评估与治疗方案制定提供参考依据，尤其适用于预计存在治疗延迟的病例。