Percentage of sarcomatoid component as a prognostic indicator for survival in renal cell carcinoma with sarcomatoid dedifferentiation

Abstract

OBJECTIVE Renal cell carcinoma with sarcomatoid dedifferentiation(sRCC) is associated with higher stage of presentation and worse survival. The objective of this study was to examine the clinicopathological characteristics associated with overall survival(OS), specifically examining the percentage of sarcomatoid component(PSC). METHODS We reviewed clinicopathologic data for all nephrectomized patients with confirmed sRCC. Histologic slides were re-reviewed by dedicated GU pathologists to ascertain PSC. Patient characteristics were tabulated overall and by disease stage. Cutpoints in the PSC providing a meaningful difference in OS were identified by recursive partitioning analysis(RPA). Factors selected included age group, gender, race, clinical stage, tumor histology, presurgical systemic therapy, lymphovascular invasion, and tumor size. Kaplan-Meier method and log-rank test were used to assess differences in OS. RESULTS Among 186 patients with sRCC, 64(34%) had localized, and 122(66%) had metastatic disease at presentation. Patients had primarily clear cell histology(73%). Median follow-up was 12.1 months(range 0.1–242.2 months). Median OS was 12.6 months (95%CI 10.7–14.9 months). Univariate RPA identified a PSC cutpoint of 10% as prognostically significant. Patients with PSC>10% were at higher risk of death compared to patients with ≤10%(45% vs. 61% 1-year OS;P=0.04). Multivariate RPA revealed that tumor size, presence of metastatic disease, and PSC were significantly associated with OS. Among 4 identified groups, patients with localized disease and tumor size ≤10cm were most likely to be alive at 1 year(89%), and patients with metastatic disease and PSC>40% were least likely to be alive at 1 year(28%;p<0.001). CONCLUSION PSC appears to be a prognostic factor in patients with sRCC, with larger percentage of involvement portending a worse survival, especially in patients with metastatic disease.

Outcomes of Patients with Renal Cell Carcinoma and Sarcomatoid Dedifferentiation Treated with Nephrectomy and Systemic Therapies: Comparison between the Cytokine and Targeted Therapy Eras

“…In addition, the vast majority of our patients (92%) presented with symptoms related to their primary tumor or metastatic disease. Consistent with previous reports, 26 our analysis suggested that patients with higher percentages of sarcomatoid component have shorter median OS (Supplementary Figure 4). Detecting sarcomatoid features by biopsy of the primary renal tumor or a metastatic site prior to nephrectomy is challenging.…”

WHO/ISUP classification, grading and pathological staging of renal cell carcinoma: standards and controversies

“…Tumours consisting only of sarcomatoid cells are placed in the ‘unclassified’ category in the WHO classification [1]. The extent of sarcomatoid morphology has been shown to adversely affect survival, but there is no international agreement on how this can be measured and reported reliably [92, 93]. …”

Impact of sarcomatoid differentiation and rhabdoid differentiation on prognosis for renal cell carcinoma with vena caval tumour thrombus treated surgically

“…We believe that the equivalence of sarcomatoid differentiation and grade 4 classification in RCC may underestimate the prognostic value of sarcomatoid differentiation. Furthermore, Adibi et al [19] found that the percentage of sarcomatoid differentiation (PSD) was a prognostic factor for overall survival in RCC. Zhang et al [20] suggested that PSD was an independent predictor of prognosis.…”