WSSP Challenging Cases in Bone and Soft Tissue Pre-Test Name* First Last Credentials (MD, PhD, etc.) Email* Uncommon Presentations of (relatively) Common SarcomasJose G. Mantilla Arango, MD1. Molecular diagnosis in liposarcoma is important because of the following:*a. DDIT3 amplification in dedifferentiated liposarcoma portends a poor prognosis.b. It is not. Most cases of liposarcoma can be accurately classified based on morphology.c. Different subtypes of liposarcoma may have overlapping morphologic features; prognosis and treatment modalities can vary based on molecular findings.d. Pleomorphic liposarcomas are highly responsive to combination therapy.2. The following is true regarding the incidence of retroperitoneal liposarcoma:*a. Liposarcomas with MDM2 amplification are the main diagnostic consideration.b. Retroperitoneal myxoid liposarcoma is relatively common in young individuals.c. Pleomorphic liposarcoma is the most common subtype overall.3. The following is true regarding malignant peripheral nerve sheath tumors:*a. They are defined by specific cytogenetic changes.b. The presence of heterologous differentiation is associated with a better prognosis.c. The vast majority of cases are associated with plexiform neurofibromas.d. Although rare, MPNST can arise in schwannomas, especially in the setting of prior radiation therapy.4. Regarding the distinction between synovial sarcoma from other fusion-defined morphologic mimics, the following is true:*a. It is important to accurately distinguish these lesions, since their overall survival and response to chemotherapy can be very different.b. It is not important to distinguish these lesions, since their biological behavior is essentially the same.c. A combination of cytokeratin, CD99 and WT-1 immunohistochemical stains can help classify most cases.d. Sarcomas with CIC-DUX4 fusion tend to have an indolent behavior when compared to synovial sarcomas.5. Regarding primary sarcomas of the larynx, the following is true:*a. Sarcomatoid carcinomas are much more common, and the main diagnostic consideration.b. Chondrosarcomas are rare when compared to other subtypes.c. Most cases do not demonstrate a line of differentiation.d. SATB2 expression is diagnostic of osteosarcoma.6. Which of the following is true regarding angiomatoid fibrous histiocytoma:*a. Most cases are seen in elderly patientsb. It is an invariably aggressive malignant neoplasm.c. Most cases have gene fusions involving EWSR1d. Morphologic features are useful for predicting malignant behavior.Histologic Mimics of Soft Tissue NeoplasmsEleanor Chen, MD, PhD1. Which of following is NOT true about pseudomyogenic hemangioendothelioma?*a. Multifocality is a frequent presentation.b. It tends to occur in young men.c. The tumor shows muscle differentiation.d. Can occur in both soft tissue and bone.2. Which of the following translocations has been identified in epithelioid hemangioendothelioma (EHE)?*a. ASPL-TFE3b. YAP1-TFE3c. JAZF1-PHF1d. TFE3-MITF3. Which of the following infectious agents causes Kaposi sarcoma?*a. HPVb. Bartonella henselaec. HHV8d. EBV4. Which of the following panel of immunohistochemistry markers is most useful for differentiating pseudomyogenic hemangioendothelioma from other histologic mimics?*a. AE1/AE3, D2-40, INI1, CD34b. MNK-116, DESMIN, MYOGENINc. CAM5.2, CD34, DESMINd. AE1/AE3, CD31, ERG, DESMIN, INI15. Which of the following markers is NOT useful in distinguishing carcinoma from epithelioid angiosarcoma?*a. AE1/AE3b. CD31c. ERGd. CD346. Which of the following findings is not true regarding myxoinflammatory fibroblastic sarcoma (MIFS)?*a. It is likely related to hemosiderotic fibrolipomatous tumor (HFLT).b. TGFBR3-MGEA5 fusion has been identified in hybrid MIFS/HFLT.c. It is a sarcoma with high metastatic potential.d. It occurs mostly frequently in the distal extremities.