Acquired von Willebrand syndrome associated with plasma cell myeloma - a rare histopathological bone marrow image.

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder that is associated with a variety of underlying diseases. We report a case of AVWS associated with plasma cell myeloma. The patient was a 57-year-old male with recurrent bleeding symptoms for a few months. Physical examination was normal. Laboratory studies revealed isolated prolongation of the activated partial thromboplastin time. His factor VIII activity, von Willebrand factor (VWF) Ag, and VWF activity were low. Bone marrow aspirate showed diffuse infiltration of atypical plasma cells and erythroid line hyperplasia.

Pigmented/melanocytic malignant perivascular epithelioid cell tumor with TFE3-SFPQ(PSF) rearrangement - a challenging diagnosis of PEComa family of tumors.

We here report a case of a distinct subtype of pigmented/melanocytic malignant PEComa with TFE3-SFPQ(PSF) rearrangement. The tumor involved the iliac region and clinically mimicked metastatic melanoma. The immunohistochemical assessment was supplemented with molecular studies including fluorescence in situ hybridization (FISH) and next-generation sequencing sarcoma panel (NGS). We also discuss the differential diagnosis of intraabdominal PEComas and emphasise the recent molecular reports on the TFE3 rearranged tumors.