Prognostic factors and survial of advanced renal cell carcinoma with predominant sarcomatoid histology.
400 Background: Sarcomatoid renal cell carcinoma (SRCC) is known to have aggressive clinical course and poor response to treatment. Very limited data of clinical feature, prognostic factor, and survival are available for advanced disease with predominant sarcomatoid histology. We evaluated clinical features, response to treatment, and prognostic factors for survival. Methods: Between 2001 and 2010, 30 patients with metastatic or recurrent RCC with predominant sarcomatoid histology (sarcomatoid component 30% or more for resected kidney or exclusive sarcomatoid carcinoma on needle biopsy) were treated at our institution. We reviewed these patients' records to identify clinical and pathologic features which could affect survival. The role of nephrectomy and systemic therapy on patient outcome was also investigated. Results: There were 20 male and 10 female patients with a median age of 58 years (range, 43–83). Twenty patients had initially metastatic disease and 16 patients (53%) had ECOG performance status (PS) of 0–1. The most frequent metastatic site was lung (57%) followed by bone (43%) and distant lymph nodes (23%). Fourteen (70%) out of 20 patients with initially metastatic disease underwent primary nephrectomy and six patients also underwent metastasectomy. The median % of sarcomatoid component was 80% (range, 30–100%). All patients (N=10) who received immunotherapy had progressive disease as their best response and only one out of 5 patients treated with sunitinib or everolimus had a partial response. With a median follow-up duration of 22 months, the median survival was 3.6 months (95% CI, 0∼7.5) with 6-month survival rate of 43%. Only ECOG PS had impact on survival (P<0.001: ECOG=0, 14.1 months; ECOG=1, 7.4 months; ECOG=2, 3.2 months, and ECOG=3, 1.64 months). Survivals for initially metastatic disease were not significantly different whether patients underwent nephrectomy or not (2.0 months vs. 3.4 months, HR=0.62, 95% CI, 0.16–2.44 after correcting for potential prognostic factors). Conclusions: Patients with SRCC have a fulminant clinical course and the majority of patients had disease progression irrespective of any treatment. Only performance status dose have impact on overall survival. No significant financial relationships to disclose.