eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2016-06-25 4 6 215 217 10.12691/ajmcr-4-6-8 AJMCR2016468 article Heidarali Esmaeili 1 Haniyeh Amidfar hany_med2005@yahoo.com 2 Mehrdad Yavarikia 3 Atiyeh Amidfar 4 Department of General Pathology, Tabriz University of Medical Science Assissstant of Pathology, Iran Department of Cardiology, Tabriz University of Azad Medical Science Department of Gynecology, Tabriz University of Medical Science Background: Chondroblastoma is a rare benign cartilaginous neoplasm that considered for approximately 1% of all bone tumors and characteristically emerges in the epiphysis of a long bone, especially the hummeros, femurand tibia.Only rare cases have been reported in the diaphyseal region. Case Report: We report a case of diaphyseal one in a 13 years old girl that admitted ith brief pain and deformities in left leg. Radiographic examinations disclosed a multiloculated osteolytic lesion in left tibia. Conclusion: Histologicak findings revealed proliferation of polygonal cells in the cartigenous background with few Giant cells. http://pubs.sciepub.com/ajmcr/4/6/8/ajmcr-4-6-8.pdf Chondroblastoma Diaphysis chondroblasts