Case reports of diagnostic error: liposarcoma mistaken for hematoma in an obese female with concurrent ipsilateral thrombosis on rivaroxaban.

We report the case of a morbidly obese 49-year-old female found to have a 16×14×10 cm high grade myxoid liposarcoma of the thigh initially diagnosed as a hematoma. Recent initiation of rivaroxaban for a coincident ipsilateral popliteal vein thrombosis placed hematoma high in the differential diagnosis. Despite its large size, the mass was not directly appreciable on physical exam due to excess adjacent adipose tissue. Diagnostic success was achieved only after anchoring bias was abandoned and adaptive expertise was applied.

[Molecular pathology of sarcomas. Update on the research group "Molecular Diagnosis of Sarcomas"]. / Molekularpathologie von Sarkomen. Erste Ergebnisse des Sarkomforschungsverbundes KoSar.

To establish precise diagnostic algorithms and standardised treatment of sarcomas in specialized centers, the interdisciplinary research group KoSar (sarcoma competence network) has been funded by German Cancer Aid. A sarcoma tissue repository and a diagnostic reference center have been set up, presently containing about 1000 accurately diagnosed sarcomas of different entities. Significant gene expression profiles for synovial sarcomas, leiomyosarcomas, myxoid liposarcomas and a small profile for myxofibrosarcomas as well as a new classification of angiosarcomas were defined. We systematically searched for activated signal transduction pathways in sarcoma cell lines and xenograft transplant models and candidate targets for molecular therapies were identified. Based on these results first clinical studies have been initiated by the German Interdisciplinary Sarcoma Study Group (GISG).