Embryonal sarcoma of the liver is a rare, aggressive malignant tumor that typically occurs in children and teenagers. Microscopic features include spindle, oval, or stellate cells with poorly defined cell borders, nuclear pleomorphism and multinucleation, and variable immunoreactivity to cytokeratin, vimentin, and alpha-1-antitrypsin. Intracellular and extracellular PAS-positive, diastase-resistant hyaline globules are commonly present. The authors evaluated a panel of IHC stains to better define the pattern of immunoreactivity in this tumor. Embryonal sarcomas of the liver were identified from archival files and were immunostained with antibodies: cytokeratin AE1/3, hepatocyte, SMMS, myogenin, calponin, h-caldesmon, desmin, S100, vimentin, CD34, C-kit (CD117), CD10, ALK-1, PE10, Bcl2, p53, and Ki-67. Six cases were identified. Patient age ranged from 6 to 24 years. Tumors ranged from 10 to 20 cm and contained spindled and epithelioid areas with PAS-positive, diastase-resistant globules and atypical cells with focal multinucleation. All cases showed immunoreactivity with vimentin and five showed immunoreactivity with Bcl2. Focal immunoreactivity was seen with cytokeratin AE1/3 in three cases, CD10 in four, calponin in two, desmin in one, and p53 in four. All tumors were negative with hepatocyte, myogenin, CD34, SMMS, h-caldesmon, PE10, ALK-1, and S100. No cytoplasmic staining was seen with C-kit. The proliferation index ranged from 30% to 95%. The diagnosis of embryonal sarcoma is based on typical morphologic features in a large liver tumor occurring in a young patient. The most useful IHC stains help to exclude tumors such as hepatoblastoma, hepatocellular carcinoma, embryonal rhabdomyosarcoma, and other sarcomas.

These findings suggest that clonality in neutrophilic dermatoses, while characteristic of underlying myeloid dyscrasia, is not observed exclusively in the setting of myeloproliferative diseases. The significance of clonal neutrophilic infiltrates unassociated with myeloproliferative disease is unclear, but it may have some implications regarding the pathogenesis of sterile neutrophilic infiltrates. Clonality is well described in the setting of lymphomatoid hypersensitivity, reflecting an overzealous response to antigenic stimuli. One could speculate a similar mechanism operational in cases of apparently reactive SS/PG associated with monoclonality; a localized form of cutaneous neutrophilic dyscrasia is also possible.

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Background: The VEGF inhibitor pazopanib is a widely used first-line therapy for the treatment of advanced renal cell carcinoma. Potential drug-drug interactions and toxicities may be underrecognized. Case Presentation: A 73-year-old woman with metastatic renal cell carcinoma on treatment with pazopanib presented with progressive inability to ambulate. The initial concern was for metastasis to the spine. However, MRI of the spine revealed diffuse muscle edema with no metastatic deposits or lytic lesions. Upon further evaluation, creatine kinase was significantly elevated and the diagnosis of rhabdomyolysis was made. With aggressive hydration and discontinuation of both pazopanib and rosuvastatin, the patient made a full recovery. Conclusion: This case of drug-induced rhabdomyolysis demonstrates an unexpected toxicity resulting from concomitant pazopanib and rosuvastatin therapy. This combination is predicted to be safe due to different, nonoverlapping effects on the cytochrome p450 enzymes. Discontinuation of statin therapy in patients with metastatic cancer should be considered when the risk of cancer-related death exceeds the risk of cardiovascular-related death.