Primary Clavicle Tumors and Tumorous Lesions in East Asia：A Systematic Review of 222 Reported Cases in Recent 29 Years

Objective The aim of this systematic review is to review the published papers from East Asia on the clinical,pathological,and epidemiological characteristics of primary clavicle tumor and tumorous lesions. Methods A computerized search based on keywords “clavicle,” “tumor,” and “tumorous lesion” (both in Chinese and in English) was performed on papers published from 1980 to 2011 in East Asian countries,including China,Japan,DPR Korea,North Korea,and Mongolia.An analysis was carried out with unified inclusion and exclusion criteria. Results Two hundred and twenty two cases were identified.The age of onset ranged from 1.5 to 70,with an average age of 29.4,and a male/female ratio of 1.53∶1.The percentage of different tumor sites was 28.9% of the cases were located in medial 1/3 region of the calvicle,18.8% in central 1/3 region and 33.6% in lateral 1/3 region；7.4% involved both the medial and central 1/3 region as well as the central and lateral 1/3 region；and 4.0% involved the full length.Major pathological types included 18.02% eosinophilic granuloma,9.91% plasmocytoma,8.11% osteosarcoma and osteochondrom,7.21% Ewing sarcoma,and 5.41% chondrosarcoma.The age of onset was found to be strongly correlated with the benign/malignant ratio.Clavicle malignancy was rarely found in patients younger than 10 years old,while the incidence of malignancy greatly was increased among patients over 40 years old.Total or subtotal claviculectomy was the most adopted treatment in cases with available treatment information.Among them,40.8% of patients in these cases received reconstruction of allograft or autograft. Conclusion Clavicle tumors and tumorous lesions in East Asia had an inclined occurrence in respect to age and gender.The most common tumors were eosinophilic granuloma and tumors derived from the bone marrow hematopoietic system.Elder age was found to be a risk factor for malignancy.These characteristics may be related to the special tissue structure and mode of development in clavicle as well as the genetic traits of the typical Mongoloid in East Asia.