Editing Non-RCC Renal Malignancies (section)

== Sarcomas of the Kidney ==

=== Background ===

*'''Renal sarcoma is less common but more lethal than sarcoma of any other genitourinary site'''

=== Epidemiology ===

*Represent 1-2% of all malignant renal tumors in adults
* Peak incidence in the 5th decade of life

=== Pathology ===

* '''Leiomyosarcoma is the most common histologic subtype of renal sarcoma'''

=== Natural History ===

*High-grade sarcomas often metastasize, with the lungs being a primary site of spread, and prognosis is poor; many patients die of disease progression in a matter of months. 
**Sarcomas are derived from mesenchymal components and are thus free of many of the natural barriers to dissemination that confine other tumor types.
*Low-grade sarcomas tend to pursue a more indolent course

=== Diagnosis and Evaluation ===

*'''Signs and Symptoms (similar to those seen with large, rapidly growing RCCs)'''
*#'''Palpable mass'''
*#'''Abdominal or flank pain'''
*#'''Hematuria'''
*Differentiation of renal sarcoma from sarcomatoid RCC is often difficult on the basis of clinical presentation, radiographic findings, and, in some cases, pathologic analysis

=== Management ===

*'''Primarily a surgical disease'''
**'''Wide excision is the goal with intraoperative monitoring of margin status'''
***The initial resection is the key event because this is the best chance for a long-term cure. 
***This often mandates RN along with en bloc excision of adjacent organs.
*'''Chemotherapy'''
**'''Has demonstrated some activity against metastatic sarcomas'''
**'''Response rates are disappointing'''
*'''Combined radiation therapy and chemotherapy'''
**'''Has proved effective in an adjuvant setting for the management of sarcomas of the extremity, has not provided much benefit for renal or retroperitoneal sarcomas'''. 
*A multimodal approach is often pursued if performance status allows, given the poor prognosis.

=== Prognosis ===

* '''Most important prognostic factors for sarcomas (2)'''
*#'''Margin status'''
*#'''Tumor grade'''