TY - JOUR A1 - Neubauer, Henning A1 - Hassold, Nicole A1 - Warmuth-Metz, Monika A1 - Winkler, Beate A1 - Kreissl, Michael C. A1 - Ernestus, Karen A1 - Beer, Meinrad T1 - Hit the mark with diffusion-weighted imaging: metastases of rhabdomyosarcoma to the extraocular eye muscles N2 - Background Rhabdomyosarcoma is the most frequent malignant intraorbital tumour in paediatric patients. Differentiation of tumour recurrence or metastases from post-therapeutic signal alteration can be challenging, using standard MR imaging techniques. Diffusion-weighted MRI (DWI) is increasingly considered a helpful supplementary imaging tool for differentiation of orbital masses. Case presentation We report on a 15-year-old female adolescent of Caucasian ethnicity who developed isolated bilateral thickening of extraocular eye muscles about two years after successful multimodal treatment of orbital alveolar rhabdomyosarcoma. Intramuscular restricted diffusion was the first diagnostic indicator suggestive of metastatic disease to the eye muscles. DWI subsequently showed signal changes consistent with tumour progression, complete remission under chemoradiotherapy and tumour recurrence. Conclusions Restricted diffusivity is a strong early indicator of malignancy in orbital tumours. DWI can be the key to correct diagnosis in unusual tumour manifestations and can provide additional diagnostic information beyond standard MRI and PET/CT. Diffusion-weighted MRI is useful for monitoring therapy response and for detecting tumour recurrence. KW - Rhabdomyosarcoma KW - Metastases KW - Extraocular eye muscles KW - DWI KW - PET/CT Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110106 ER - TY - JOUR A1 - Gerhard-Hartmann, Elena A1 - Wiegering, Verena A1 - Benoit, Clemens A1 - Meyer, Thomas A1 - Rosenwald, Andreas A1 - Maurus, Katja A1 - Ernestus, Karen T1 - A large retroperitoneal lipoblastoma as an incidental finding: a case report JF - BMC Pediatrics N2 - Background Lipoblastoma is a rare benign mesenchymal neoplasm of infancy that most commonly occurs on the extremities and trunk but can arise at variable sites of the body. Retroperitoneal lipoblastomas are particularly rare but can grow to enormous size, and preoperative diagnosis is difficult with diverse, mostly malignant differential diagnoses that would lead to aggressive therapy. Since lipoblastoma is a benign tumor that has an excellent prognosis after resection, correct diagnosis is crucial. Case presentation A case of a large retroperitoneal tumor of a 24-month old infant that was clinically suspicious of a malignant tumor is presented. Due to proximity to the right kidney, clinically most probably a nephroblastoma or clear cell sarcoma of the kidney was suspected. Radiological findings were ambiguous. Therefore, the mass was biopsied, and histology revealed an adipocytic lesion. Although mostly composed of mature adipocytes, in view of the age of the patient, the differential diagnosis of a (maturing) lipoblastoma was raised, which was supported by molecular analysis demonstrating a HAS2-PLAG1 fusion. The tumor was completely resected, and further histopathological workup led to the final diagnosis of a 13 cm large retroperitoneal maturing lipoblastoma. The child recovered promptly from surgery and showed no evidence of recurrence so far. Conclusion Although rare, lipoblastoma should be included in the differential diagnoses of retroperitoneal tumors in infants and children, and molecular diagnostic approaches could be a helpful diagnostic adjunct in challenging cases. KW - retroperitoneal tumor KW - pediatric KW - lipoblastoma KW - PLAG1 rearrangement KW - case report Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260173 VL - 21 ER -