case_images: PMC9069099_01
case_images: CT thorax: (A1, 2) (Shanxi Provincial Cancer Hospital,2021-02-03) shows a large irregular and well-defined border mass lesion measuring 7.7x6.3 cm with inhomogenous enhancement beside the left hilus pulmonis across the interlobar fissure and an enlarged mediastinal lymph node measuring 2.7x1.9 cm. (B1, 2). (Shanxi Provincial Cancer Hospital,2021-05-12)Tumor was remarkable reduced to 2.5*3.4cm and the mediastinal lymph node was 1.2 cm.
case_images: fonc-12-822469-g001.jpg
case_images: PMC9069099_01_fonc-12-822469-g001.jpg
case_images: f1
case_images: Only 16 days later, CT thorax in our hospital revealed the mass increased to 7.7 x 6.3cm and an enlarged mediastinal lymph node measuring 2.7x1.9 cm. ( Figure 1 ).
case_images: Pathological examination. (A) H&Ex200/400 cell block shows small round tumour cells; (B) CD99(+)x200/400; (C) AE1/AE3(-)x200/400 (D) TTF-1(-)x200/400 (E) Ki67(appro. 80%+x400); (F) FISH shows EWSR1 gene rearrangement.
case_images: fonc-12-822469-g002.jpg
case_images: PMC9069099_01_fonc-12-822469-g002.jpg
case_images: f2
case_images: TTF-1(-) and Syn(+). A fluorescent in situ hybridization (FISH) assay showed positive rearrangement of the ESWR1 gene  Figure 2 .
case_images: The evariation trend of the size of the tumor and the mediastinal lymph nod.
case_images: fonc-12-822469-g003.jpg
case_images: PMC9069099_01_fonc-12-822469-g003.jpg
case_images: f3
case_images: On March 4th, March 23rd and May 12th, 2021, CT thorax re-examination showed that the size of the left mass was significantly decrease (5.8*4.7cm,4.3*2.7cm and 3.4 *2.5cm, respectively) ( Figure 3 ).