Multiple chromosome abnormalities in the pleural fluid of a patient with recurrent Ewing sarcoma

The authors report a 5.5-year-old male patient with a right paraspinal tumor, diagnosed as metastatic Ewing sarcoma. The pleural fluid along with the bone marrow was sent to the authors' laboratory for karyotyping. Bone marrow cultures revealed a normal karyotype, whereas 48, XY, i(1)(q11), +10, t(11;22)(q24;q12) karyotype was found in the cells obtained from the pleural fluid cultures. Trisomy 1q is quite frequently observed in Ewing sarcoma patients, mostly as part of unbalanced translocations, along with the common t(11;22) translocation. This patient's findings were significant, as the complex karyotype in the pleural effusion cells was observed.