en Orthopedic Surgery Orthopedic Surgery case report case report <p> <strong> Abstract </strong></p><p>  A solitary plasmacytoma of bone occurs in approximately 2-5% of patients with </p><p>  myeloma. The lesion mostly found in the axial skeleton and have infrequently been </p><p>  reported to arise in the hand, and usually occur in the distal phalanges. We report the </p><p>  interesting case of a 75-year-old man who developed a solitary lytic lesion of the </p><p>  thumb proximal phalanx. This lesion was explored through MR imaging and histologic </p><p>  examination, and then a final diagnosis of plasmacytoma was determined. He </p><p>  was treated with fractionated radiotherapy and no complication was detected with </p><p>  this procedure. The clinical, imaging, and histologic findings of this case are presented </p><p>  here. </p> plasmacytoma, thumb, proximal phalanx 173 176 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-80&slc_lang=en&sid=1 Dawood Jafari 20031947532846001862 20031947532846001862 No Iran University of Medical Sciences, Tehran, Iran. Hamid Taheri 20031947532846001863 20031947532846001863 No Iran University of Medical Sciences, Tehran, Iran. Hooman Shariatzadeh 20031947532846001864 20031947532846001864 No Iran University of Medical Sciences, Tehran, Iran. Farid Najd Mazhar 20031947532846001865 20031947532846001865 No Iran University of Medical Sciences, Tehran, Iran Alireza Pahlevansabagh pahlevansabagh@yahoo.com 20031947532846001866 20031947532846001866 Yes Department of Hand Surgery, Shafa Yahyaian Hospital, Baharestan Sq. Tehran, Iran.