Mesoblastic Nephroma : Treatment
Section Editor: Dharam M. Ramnani, MD
Virginia Urology, Richmond, VA, USA
Image Description
Treatment & Prognosis: Complete excision with wide margins is curative and is associated with an excellent prognosis (5-yr survival rate of 95%). Further treatment (radiation therapy and chemotherapy) is not necessary.
Recurrences or metastases occur in 5%-7% of cases. Adverse prognostic factors include cellular variant histology, age greater than 3 months at the time of resection, tumor rupture, lymphovascular invasion and infiltration into the renal sinus. Recurrent tumors locally invade the retroperitoneum, whereas the sites of distant metastasis are lungs, liver, and brain. In TRK-fusion positive cases, the use of selective TRK inhibitors such as Larotrectinib and Entrectinib in metastatic setting has shown promising results.
This intermediate power view of a classic mesoblastic nephroma shows intersecting bundles of spindle cells creating an appearance reminiscent of a uterine leiomyoma. Entrapped glomeruli and tubules can also be seen. Some cases contain islands of hyaline cartilage and extramedullary hematopoiesis.
Recurrences or metastases occur in 5%-7% of cases. Adverse prognostic factors include cellular variant histology, age greater than 3 months at the time of resection, tumor rupture, lymphovascular invasion and infiltration into the renal sinus. Recurrent tumors locally invade the retroperitoneum, whereas the sites of distant metastasis are lungs, liver, and brain. In TRK-fusion positive cases, the use of selective TRK inhibitors such as Larotrectinib and Entrectinib in metastatic setting has shown promising results.
This intermediate power view of a classic mesoblastic nephroma shows intersecting bundles of spindle cells creating an appearance reminiscent of a uterine leiomyoma. Entrapped glomeruli and tubules can also be seen. Some cases contain islands of hyaline cartilage and extramedullary hematopoiesis.