Qap (Anatomical Pathology) 

QAP Peer Review

AP297
Case History: F/65 Left lower limb tumor
Intended diagnosis: Myxoid malignant fibrous histiocytoma / myxofibrosarcoma. Contributed by:MW
Code Diagnosis Comment Score
anonymous High grade sarcoma (100%), differential diagnoses are myxofibrosarcoma and de-differentiated liposarcoma Immunostains for CDK4 and p16 are positive in de-differentiated liposarcoma. MDM2 amplication can be demonstrated by FISH test in liposarcoma.  100
anonymous Liposarcoma nil  50
anonymous Low grade myxoid sarcoma Differential diagnosis myxofibrosarcoma or myxoid liposarcoma  50
anonymous Well-differentiated liposarcoma 90% Myxofibrosarcoma 10% 1. Perform immunohistochemical studies or FISH for CDK4 and mdm2 to confirm well-differentiated liposarcoma; 2. Sample more blocks to look for more typical well-differentiated liposarcoma and possible de-differentiation area.  60
anonymous Myxoid liposarcoma Unlikely ddx: sclerosing well differentiated liposarcoma should be MDM2+ and CDK4+. Myxoid liposarcoma has t(12,16) or t(12,22) translocation.  50
anonymous Myxoid malignant fibrous histiocytoma (100%) nil  100
anonymous Left lower limb tumour, DDx: 1. Myxofibrosarcoma 80% 2. Well differentiated liposarcoma 20% Ensure adequate sampling for definitive diagnosis, immunohistochemistry with markers MDM2 and CDK4 to rule in/out WD liposarcoma  100
anonymous Sarcoma, favour myxofibrosarcoma (90%), differential diagnosis includes myxoid liposarcoma (5%) and well differentiated liposarcoma (5%) extensive sampling to look for lipoblast  100
anonymous Myxofibrosarcoma 100% nil  100
anonymous Dedifferentiated liposarcoma nil  70
anonymous SOFT TISSUE tumour, left lower limb - MYXOFIBROSARCOMA nil  100
anonymous Myxofibrosarcoma nil  100
anonymous Soft tissue - Well differentiated liposarcoma With focal pleomorphic area. Examine more blocks from tumour.  50
anonymous dedifferentiated liposarcoma (100%) nil  70
anonymous low grade fibromyxoid sarcoma. 100% nil  50
anonymous high grade sacrcoma liposarcoma nil  60
anonymous Pleomorphic liposarcoma 100% nil  60