Huge heterogeneous cystic mass on enhanced CT. Gross and microscopic pathological

Huge heterogeneous cystic mass on enhanced CT. Gross and microscopic pathological analysis showed that the cysts contained necrotic tissues. These findings are not typical of CCSK. Radiographically demonstrable calcification is observed in 3?7 of primary Wilms tumors [3, 4], but calcification is rarely reported in CCSK. Glass et al. reported calcification in CCSK, which was detected as acoustic shadowing on sonography, indicating a calcific deposit [5]. In the present case, calcification was detected on CT. The pathological findings revealed that the calcification was present around the sphacelus, which is considered dystrophic calcification attributable to necrosis [6]. These results suggest that huge areas ofnecrosis and calcification are not reasons to reject a diagnosis of CCSK. The abnormal karyotype t(10;17)(q22;p13) has been reported previously in CCSK [7], and CpG sites in the THBS1 gene were shown to be specifically hypermethylated in CCSK [8]. A new chromosomal abnormality was detected in our patient, 46,XY,der(3)(3pter PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/15501003 3q23::7?::3?::7p13 7pter)der(7)(X?::7p11.2 7q22::3?::Xq13 Xqter)der(X) del(X)(p11.2p22.1)t(X;7)(q11;?). A complex karyotype, containing chromosomal 3, chromosomal 7, and X chromosomal abnormalities, was detected with spectral karyotyping FISH, in which a fragment of chromosome 7 was added to the partially deleted X chromosome. It is unclear whether this abnormality was involved in the development of CCSK, although renal cell sarcoma (RCC) with an Xp11.2 translocation has been reported [9?1]. Calcification and CCSK occurrence, which were two features of our patient, in an older child or young adult are characteristics of RCC with the Xp11.2 translocation [9?1]. Interestingly, both patients with Xp11.2 RCC and our patient display X-chromosome abnormalities.Fig. 2 Gross pathological findings. The tumor weighed approximately 750 g and measured 15 ?12 ?9 cm. The left kidney is replaced by the neoplasm. Calcification is apparent around the necrotic tissueFig. 3 Microscopic pathological analysis. Small oval cells arranged in nests or cords are separated by fibrovascular septa. Plump or spindle-shaped cells contain clear cytoplasmKato et al. Diagnostic Pathology (2015) 10:Page 3 ofFig. 4 Fluorescence in situ hybridization of tumor chromosomes. A new chromosomal abnormality, 46,XY,der(3)(3pter 3q23::7?::3?::7p13 7pter)der(7)(X?::7p11.2 7q22::3?::Xq13 Xqter)der(X)del(X)(p11.2p22.1)t(X;7)(q11;?), was identified in the tumorTherefore, it is likely that an X-chromosome aberration produces an atypical pathogenesis in CCSK, including calcification and huge areas of necrosis. CCSK is considered an unfavorable histological renal tumor by the National Wilms Tumor Study Group (NWTSG) and JWiTS [1, 2, 12?4]. The survival rate for stage 2 CCSK is reported to be 75 when doxorubicin is added Lenalidomide to the therapeutic regimen [1, 2, 13, 14]. However, necrosis is reported to increase the risk of tumor-related mortality in CCSK [13]. Our patient requires careful follow-up.Author details 1 Department of Pediatrics, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293, Japan. 2Department of Radiology, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293, Japan. 3Department of Anatomic and Diagnostic Pathology, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293, Japan. 4First Department of Surgery, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293, Japan. Receiv.