Transforming the Perioperative Treatment Paradigm in Non-Metastatic RCC-A Possible Path Forward

In 2017, there is no adjuvant systemic therapy proven to increase overall survival in non-metastatic renal cell carcinoma (RCC). The anti-PD-1 antibody nivolumab improves overall survival in metastatic treatment refractory RCC and is generally tolerable. Mouse solid tumor models have revealed a benefit with a short course of neoadjuvant PD-1 blockade compared to adjuvant therapy. Two ongoing phase 2 studies of perioperative nivolumab in RCC patients have shown preliminary feasibility and safety with no surgical delays or complications. The recently opened PROSPER RCC trial (A Phase 3 RandOmized Study Comparing PERioperative Nivolumab vs. Observation in Patients with Localized Renal Cell Carcinoma Undergoing Nephrectomy; EA8143) will examine if the addition of perioperative nivolumab to radical or partial nephrectomy can improve clinical outcomes in patients with high risk localized and locally advanced RCC. With the goal of increasing cure and recurrence-free survival (RFS) rates in non-metastatic RCC, we are executing a three-pronged, multidisciplinary approach of presurgical priming with nivolumab followed by resection and adjuvant PD-1 blockade. We plan to enroll 766 patients with clinical stage ≥T2 or node positive M0 RCC of any histology in this global, randomized, unblinded, phase 3 National Clinical Trials Network study. The investigational arm will receive two doses of nivolumab 240 mg IV prior to surgery followed by adjuvant nivolumab for 9 months. The control arm will undergo the current standard of care: surgical resection followed by observation. Patients are stratified by clinical T stage, node positivity, and histology. The trial is powered to detect a 14.4% absolute benefit in the primary endpoint of RFS from the ASSURE historical control of 55.8% to 70.2% at 5 years (HR = 0.70). The study is also powered to detect a significant overall survival benefit (HR 0.67). Key safety, feasibility, and quality of life endpoints are incorporated. PROSPER RCC exemplifies team science with a host of planned correlative work to investigate the impact of the baseline immune milieu and changes after neoadjuvant priming on clinical outcomes.

PD-L1 Expression in Clear Cell Renal Cell Carcinoma: An Analysis of Nephrectomy and Sites of Metastases

Background: Expression of programmed death ligand (PD-L1/B7-H1/CD274) represents a mechanism of immune escape for renal cell carcinoma (RCC) cells. Drugs blocking PD-L1 or its receptor are in clinical development and early data suggests that tumor PD-L1 expression may predict response.

Patients and Methods: A tissue microarray (TMA) consisting of four biopsy cores from 34 matched pairs of nephrectomy and metastatic sites of clear cell RCC was used to assess PD-L1 expression by quantitative immunofluorescence. Assessment of intra- and inter-tumor heterogeneity and primary and metastatic tumor expression was performed using a method of Automated Quantitative Analysis (AQUA).

Results: The median AQUA scores were higher in metastatic than primary specimens (P < 0.0001). The correlation between PD-L1 expression in matched primary and metastatic specimens was weak (R= 0.24). Within a given tumor, variable PD-L1 staining heterogeneity was seen, however the degree of heterogeneity was similar in primary and metastatic sites (P = 0.482).

Conclusions: The weak correlation between PD-L1 expression in primary and metastatic sites for a given patient suggests that expression in nephrectomy specimens cannot be used to select metastatic RCC patients for PD-L1 and PD-1 inhibitors. The intra-tumor heterogeneity seen in both primary and metastatic specimens indicates that a single core biopsy might not be sufficient to determine PD-L1 expression.

Impact of pathologic tumor characteristics in patients with sarcomatoid renal cell carcinoma

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Background: Patients with sarcomatoid renal cell carcinoma (sRCC) are known to have a poor prognosis and response to therapy. We sought to determine the influence of pathologic tumor characteristics on outcome in order to aid clinical management.

Methods: A single center database was reviewed from 1989-2009 to identify all patients with sRCC. Clinical and staging variables were collected and pathologic information including histology, necrosis, percentage of sarcomatoid features (PSF), and microvascular invasion (MVI) was recorded. Influence of clinicopathologic variables on outcome was assessed.

Results: A total of 104 patients had confirmed sRCC. The median size of tumors was 9.5 cm (range 2.5-30), 65% of patients had areas of clear cell RCC, and 69.2% had metastatic disease at presentation. The PSF did not influence tumor size, stage, necrosis, MVI, nodes, or metastasis. A total of 85 patients (81.7%) died during the follow-up period with a median survival of 5.9 months. In the overall cohort poor performance status, metastatic disease, and MVI were independent predictors of poor survival. Increased PSF was associated with worse outcome, but it failed to reach significance on multivariate analysis. In a subset analysis of those with non-metastatic disease, MVI and non-clear histology influenced prognosis, but only PSF was the only predictor of outcome.

Conclusions: The PSF has limited influence on pathologic characteristics. However, increased PSF amounts may impact survival, especially in those with non-metastatic disease. The presence of MVI is an independent predictor of poor outcome while carcinoma grade and subtype have limited impact on survival. When counseling patients or designing clinical trials for these patients, PSF and MVI, not carcinoma grade or subtype should be considered.

No significant financial relationships to disclose.

Use of CA9 gene single nucleotide polymorphisms to predict prognosis and treatment response of metastatic renal cell carcinoma

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Background: Carbonic anhydrase 9 gene (CA9) is located in a prognostically relevant chromosomal area on chromosome 9p and is encoding for one of the most significant protein markers in metastatic renal cell carcinoma (MRCC), CAIX. In contrast to CAIX protein, however, no efforts have been made to date to study CA9 gene in metastatic RCC. Here, we test the hypotheses that single nucleotide polymorphisms (SNPs) and mutations of the CA9 gene are associated with CAIX expression, response to immunotherapy and survival. Methods: Genomic DNA was extracted from frozen tumor samples of 54 patients with clear cell MRCC. All exons of the CA9 gene were PCR-amplified and sequenced. The antibody M75 was used to evaluate CAIX protein expression immunohistochemically. Statistical associations of CA9 gene status and CAIX protein expression with response to IL-2 based immunotherapy and overall survival were assessed with chi-square tests, t-tests, Kaplan-Meier survival estimates and Cox proportional hazards regression models. Results: CA9 reference SNP (rs) 2071676 was found in 59%, rs12553173 in 15%, rs3829078 in 11% and rs1048638 in 33% of the patients. The deletion c.376del393 was observed in two patients. CAIX expression was high (>85%) in 65% of the patients. None of the SNPs was significantly associated with CAIX expression. Patients with the C allele variant of rs12553173 had improved median survival (27.3 vs. 13.6 months, p = 0.0431) and a greater likelihood of response to IL-2 (57% vs. 22%, p = 0.081) Likewise, high CAIX expression was associated with longer median survival (25.5 vs. 8.5 months, p < 0.0001) and a greater IL-2 response rate (37% vs. 8%, p = 0.070). In a multivariate Cox model, both C allele variant of CA9 SNP rs12553173 and CAIX expression were retained as independent prognostic factors. Conclusions: CA9 SNPs are frequently found in patients with MRCC. The C allele variant of rs12553173 is associated with improved overall survival and a greater likelihood of response to IL-2. CA9 rs12553173 and CAIX are both independent prognostic factors of overall survival and complementary in predicting prognosis of MRCC.

No significant financial relationships to disclose.

Use of chromosome 9p status to identify a subset of high-risk localized renal cell carcinoma

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Background: We investigated whether deletion of chromosome 9p in clear cell renal cell carcinoma (ccRCC) predicts worse disease-specific (DSS) and recurrence-free survival (RFS), and if it is associated with worse prognosis in tumors < 4 cm. Methods: 316 patients undergoing nephrectomy prior to 2001 were included on a tissue microarray in whom FISH analysis using the LSI p16/CEP 9 Dual Color Probe was performed to assess chromosome 9p deletion status. An additional 389 patients undergoing nephrectomy after 2001 had 9p status determined by standard cytogenetics. Tumor grade, stage, size, 9p status, nodal involvement, and the presence of metastasis were recorded. Disease-specific and recurrence-free survival were determined, and independence was assessed using Cox proportional hazards models. Results: 9p deletions were detected in 14% of tumors. 54% of 9p-deleted tumors were high grade (G3–4) vs. 38% without 9p deletions, and 60% of 9p-deleted tumors were T3–4 vs 38% without 9p deletions (p < 0.01). 55% of those with 9p deletions had positive nodes or metastases vs. 34% of those without 9p deletions (p < 0.01). Median DSS for those with and without 9p deletions was 80 months and 37 months, respectively (p < 0.01). In localized disease, median RFS for those with 9p deletions was 53 months and was not reached in those without 9p deletions (p<0.01). In 188 patients presenting with localized RCC < 4 cm, loss of 9p occurred in 3/7 (42.9%) of patients with post-nephrectomy recurrence vs. 13/168 (7.2%) of patients without disease recurrence (p = 0.001). DSS for patients with 9p deletion in tumors < 4 cm was significantly worse than DSS in those without 9p deletions (HR 6.18; p = 0.02), and an independent effect on RFS was seen for 9p deletions in localized RCC (HR 2.3, p < 0.01). 9p status was not a significant predictor in metastatic RCC. Conclusions: Deletion of chromosome 9p in ccRCC occurs in 14% of patients and is associated with higher grade and T stage, presence of nodal and distant disease, worse prognosis, and in patients with small NOMO tumors, 9p deletions but not tumor size was independently associated with RFS. Identifying high risk patients with 9p deletions will allow better risk stratification for surveillance protocols and for adjuvant trials.

No significant financial relationships to disclose.