Today’s case is a 4-year-old female neutered Mastiff with a 3-week history of a growing mass and lameness. Take a look at the case, and post your comments below.
4 year old Mastiff
Teaching and learning about veterinary diagnostic imaging.
A large soft tissue mass is present along the caudomedial aspect of right femur. The right stifle joint may have increased synovial volume; however, additional radiographs are required for accurate evaluation. No abnormalities are present in the remainders.
These findings represent possible soft tissue origin neoplasia such as rhabdomyosarcoma, melanoma, hemangiosarcoma or lymphoma. Infiltrative lipoma or liposarcoma cannot be ruled out. Further diagnostic imaging such as throacic rads or CT scan and biopsy are recommned.
A large soft tissue mass is present at the caudomedial aspect of the right pelvic limb from the pelvis to the proximal tibia. No osteolysis of the adjacent femur or tibia is observed. The soft tissue mass is partially superimposed on the stifle joint, but a normal infrapatellar fat pat is observed. There is enthesophytosis of the supracondylar eminences of the distal femur and periarticular remodeling of the stifle joint.
Impressions: Soft tissue mass at the caudomedial aspect of the proximal right pelvic limb. Ddx: neoplasia (fibrosarcoma, rhabdomyoma / sarcoma, other soft tissue sarcoma, or less likely hemangiopericytoma); other causes of a soft tissue mass, e.g. abscess or granuloma are unlikely. Periarticular remodeling of the stifle is most likely incidental, representing osteoarthrosis, as the mass is not centered on the joint. Thoracic radiographs are recommended given that neoplasia is the top ddx. Ultrasound of limb may help characterize the mass and allow guided FNA or biopsy.