Conclusion:
The RLS remains a rare tumor and should be suggested in cas of any large
retroperitoneal tumor. It is an aggressive tumor with no typical
presentation. The complete resection of the mass and a favorable
histopathologic grade are positively associated with long-term
disease-free survival. The complete (R0) surgical resection
needs frequently an en-bloc resection of the tumor with ipsilateral
involved or encased organs in particular the kidney. Criteria in favor
of renal conservation are well encapsulated RLS, widely displaced
kidney, well differentiated RLS sub-type and patient advanced age. An
entirely encased kidney and ureteral invasion are not formal indications
for associated nephrectomy.