These tumors have been reported under various names such as leiomyomatous renal hamartoma, congenital mesoblastic nephroma
, cystic hamartoma of the renal pelvis, solitary multilocular cysts of the kidney, multilocular renal cyst with mullerian-like stroma, and adult metanephric stromal tumor (4-12).
1,2] The ossification and mesenchymal components are similar to mesoblastic nephroma
One needs to distinguish, for example, vascular malformations from vascular tumors, lipoblastoma from liposarcoma, and mesoblastic nephroma
from clear cell sarcoma of the kidney.
Solid mixed epithelial and stromal tumors also need to be distinguished from mesoblastic nephroma
and metanephric adenofibroma.
4] Carpenter and colleagues demonstrated breakpoints in the q13-15 region of chromosome 12 in leiomyomas and congenital mesoblastic nephroma
Other possible diagnoses for antenatal suprarenal cysts include benign entities, such as adrenal hemorrhage, retropleural pulmonary sequestration, neurogenic cysts, enteric duplication cysts and malignant diseases, including Wilm's tumour and congenital mesoblastic nephroma
Congenital fibrosarcoma is another spindle cell sarcoma associated with a characteristic cytogenetic change, the t(12;15)(p13;q26) translocation, not found in adult fibrosarcomas or other sarcomas (123,124) and identical to that described for congenital mesoblastic nephroma
3-11) These tumors have been published under the following names in the literature: leiomyomatous renal hamartomas, congenital mesoblastic nephroma
in an adult, cystic hamartoma of renal pelvis, solitary multilocular cysts of the kidney, multilocular renal cyst with mullerian-like stroma, and adult metanephric stromal tumor.
2) Other renal tumors of childhood have been associated with recurring genetic abnormalities: deletion or mutations of WT1 and p53 in some Wilms tumors, t (12;15) creating the ETV6-NTRK3 fusion gene in congenital mesoblastic nephroma
, and INI1 deletions or mutations in malignant rhabdoid tumors.
The differential diagnosis for mesoblastic nephroma
includes (Figure 1): a.
Pathologic Diagnosis: Mesoblastic Nephroma
, Classic Type
This does not apply to children under 11 months of age, as tumours are then often benign mesoblastic nephromas