Contributed by Faye F Gao, MD., PHD and Uma N.M. Rao, MD
The patient is an 87-year-old male who had a pathology hip fracture in April 2008, admitted with failure of the open reduction and internal fixation, requiring resection of the proximal femur with reconstruction and total hip arthroplasty and the tumor was resected mostly as a palliative measure.
X-rays showed intramedullary device to be in place, but there was destruction of the inferior head and neck of the femur. There was protrusion of the nail through the femoral head into the acetabulum with complete loss of bone. There was also a note of a second fracture just above the lesser trochanter.
The femoral head shows green-tan discoloration, was markedly brittle and fragile, and appeared to have a fracture site where the prosthesis exited. There was a rock hard tumor mass occupying about 70 % of the epiphysis and diaphysis of the excised length of the femur measuring 7 x 6.5 cm. Tumor broke through the cortex and invaded adjacent soft tissue (Figure 1). The cut surfaces of the mass were firm, white-tan to yellow. The distal 2.9 cm of femur showed red brittle bone that fractured easily upon pressure.
The tumor invaded the soft tissue circumferentially around the femur. Additional friable, fleshy, hemorrhagic and focally gritty fragments were received and the largest tumor mass measured 20.5cm in greatest dimension.
Microscopically, the tumor cells showed mitotically active pleomorphic and spindle cells. Abundant filigree osteoid as well as mineralized coarse trabeculae of malignant osteoid were present. Few chondroblastic foci were noted. Telangiectatic areas were also present (Figures 2, 3 and 4).
Host bone at a distance from the tumor showed features of Pagets disease such as irregular cement lines, scalloped bone adjacent osteoclasts, and some areas of osteoblastic rimming. The intertrabecular spaces had fibrosis and slight increase in vascularity and scant bone marrow elements (Figures 5 and 6).