Permeative lesion with wide zone of transition in the left subtrochanteric femur. Posterior cortical destruction. No pathological fracture evident.

Large left pelvic and proximal thigh soft tissue mass encases the proximal femur by more than 180 degrees. Associated cortical erosion is demonstrated with intramedullary tumor extension posteriorly where significant erosion and permeative change is seen, extending to the greater femoral trochanter. Tumor involves the entire femoral medullary cavity over a length of 14.5 cm from the femoral neck. A minimally displaced pathologic intertrochanteric fracture is also noted with horizontal and vertical components, better appreciated on coronal images. No intra-articular extension into the hip joint.

The large soft tissue tumor mass also involves the left obturator externus and internus muscles, with erosion of the left inferior pubic ramus. Tumor is also seen in the mid pelvis, inseparable from the prostate and from a 30 mm tumor nodule in the left ischioanal fossa. Tumor lies clear of the left sciatic nerve.

Normal appearance of the distal femur and proximal tibia.

No abnormality is seen in the sacrum.

No pathologically enlarged inguinal lymph nodes by size criteria.

CONCLUSION:

The pathologically diagnosed B-cell lymphoma displays a large predominantly extra osseous component in the proximal left thigh and pelvic cavity.

Intramedullary left femoral tumor extension is evident with a pathologic intertrochanteric fracture.

Prophylactic IMHS of the left femur. No hardware complication. Stable right proximal femoral permeative lesion. No pathological fracture evident.