[Unifocal Langerhans cell granulomatosis in a young woman]

We report a 24-years-old woman who presented with thoracic pain after coughing. Physical exam revealed no abnormalities except pain after pressing under blade-bone area. A rib radiography and CT of the thorax showed a lonely osteolytic lesion inside eleventh left costal arch without affecting others tissues. There were no more osteolytic lesions at other levels and the histopathological study of a resection-biopsy of the lesion was diagnosed as Langerhans' cell granulomatosis. This is an uncommon disease which diagnosis can only be made through histopathological study of suspected lesions.