Wilms tumour in horseshoe kidney

PATHOLOGY REPORTPathology report:

TISSUE ORIGINTissue origin: Right kidney.GROSS DESCRIPTIONGross description: Specimen Type: Radical nephrectomy Laterality: Right Kidney Size: Kidney dimension: 7.5 x 6 x 3.5 cm Weight: 105 grams Tumor Site: Lower area Tumor Size: 5x4x45 x 4 x 4.5 cm Tumor Characteristics: Solid and cystic with necrosis. Focality: Unifocal Adrenal gland: Not seen. Macroscopic Extent of Tumor Gerota's fascia: Intact Renal Sinus: Renal sinus involvement by tumor not identified Renal vein invasion: Absent Renal Capsule Grossly Intact: Yes. Representative sections were submitted in 17 blocks and labelled as follows: A: Renal hilum, B: Ureter, C: Tumor with parenchymal margin. D: Renal sinus, E: Tumor with pelvis F-H: Tumor, K: Kidney, L: Lymph Nodes. MICROSCOPIC FEATURESMicroscopic features: Histologic Type: Nephroblastoma, regressive type. Necrosis: Present (99% of tumor). Nephrogenic Rests: Absent. Anaplasia: Absent Margins: Margins uninvolved by tumor. Renal Sinus: Not involved. Regional Lymph Nodes: Four lymph nodes, free of tumor (0/4) Adrenal Gland: Free of tumor.Comment(s): Most of the tumor shows chemotherapy induced-induced changes (necrosis, fibromyxoid and sclerotic stroma with hemorrhage and hemosiderin-laden macrophages). Only rare microscopic foci of epithelial elements within muscular stroma and rare blastemal cellcells are seen.

DIAGNOSISDiagnosis: RIGHT KIDNEYRight kidney, RADICAL NEPHRECTOMYradical nephrectomy: Nephroblastoma, regressive type.  

• Horseshoe kidney is the most common type of congenital fusion anomaly of kidneykidneys in children. 
• Wilm's tumor tumour is the most common intra abdominal-abdominal solid mass lesion in children.
• Wilm's tumor tumour has increased incidence in horseshoe kidneys.

Large mixed echogenicity soft tissue mass lesion located in the retro peritoneumretroperitoneum of the mid abdomen.

There is a large lobulated heterogeneous density mass lesion with areas of necrosis/cystic density arising from a horseshoe kidney (involving the right kidney more than the left by claw sign). It compresses the right renal pelvis resulting in moderate hydronephrosis. The right kidney its selfitself appears hypo attenuatinghypoattenuating in comparison with the left one, probably due to a delayed nephrogram. thereThere is a suspicious of anterior abdominal wall invasion, as well as of the right liver lobe. theThe mass compressingcompresses the adjacent vessels without invasion or tumoral thrombus. There is minimalnon-specific mild stranding of the surrounding fat planes which may suggest ruptured tumor. Features are goesin keeping with Wilm's tumora Wilms tumour.