INTRODUCTION

A variety of lesions containing foreign body type or osteoclast-like giant cells occur within bone and soft tissues. These tumors demonstrate a wide range of behavior from entirely benign inflammatory or autoimmune processes such as foreign body granulomas and the granulomas of rheumatoid arthritis to highly aggressive and metastasizing neoplasms originally characterized as malignant fibrous histiocytoma (MFH) and now more commonly termed pleomorphic sarcoma. The benign inflammatory or collagen vascular diseases usually occur in the superficial subcutaneous tissue or dermis and around joints, often within the synovium. Cytologic analysis is usually successful at separating the inflammatory/collagen vascular diseases from true neoplasms including nodular tenosynovitis, conventional giant cell tumor of bone, and the various forms of giant cell rich pleomorphic sarcoma.

FOREIGN BODY REACTION WITH A PROMINENT COMPONENT OF FOREIGN BODY TYPE GIANT CELLS

Clinical features

Foreign body type granulomas may occur within the dermis and subcutaneous tissues associated with the implantation of foreign material including wood splinters, sutures, glass, and metal fragments. Usually, an inciting injury is known but in some cases the etiology is cryptogenic. In many cases, the granulomas formed are non-caseating but in some instances, central necrosis is present.