solitary neaurofibroma in lower extremity with central extensive hyalinization

Introduction: neurofibroma is a rare benign tumor that often originates from peripheral nerve sheath. the solitary type can be seen in middle-aged people. hyalinization is a rare phenomenon that can be observed in fibrous tumors. case presentation: in this report, a 46-year-old male patient with a hard mass in proximal femoral is presented. he had central necrosis in the initial imaging studies. the mass was painful and caused signs of local anesthetic for the patient. extensive hyalinization was observed in the central part of the mass in histopathological studies. s100 protein was widely positive, but cd34 and bcl2 were negative. no necrosis was observed. conclusions: the extensive central hyalinization is very rare in fibrous tumors and is observed for the first time in neurofibroma. hyalizination in the work up prior to surgical treatment led to misdiagnosis of the radiologist and the surgeon. detailed pathological examination is very important to definitive diagnosis.