Preoperative c-reactive protein and risk of major complications and mortality outcomes in patients undergoing surgery for renal cell carcinoma

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Background: C-reactive protein (CRP) has been demonstrated to be an independent predictor of survival outcomes in renal cell carcinoma (RCC). The use of biomarkers to predict post-surgical complications is not well studied. We sought to investigate predictive factors for major complications following surgery for RCC and delineate their impact on mortality outcomes. Methods: We performed a two-center retrospective analysis of patients who underwent partial (PN) and radical nephrectomy (RN) for RCC. Patients who had complications within 30 days after surgery were identified and the complications were scored using the Clavien-Dindo classification system. Patients were grouped based on whether they experienced 30-day major (Clavien ≥3) complications and whether they had elevated preoperative CRP defined as >5mg/L. Primary outcome was non-cancer mortality (NCM), with secondary outcomes being all-cause (ACM) and cancer-specific (CSM) mortality. Multivariable analyses (MVA) were conducted to evaluate predictors for Clavien ≥3 complications, NCM, CSM, and ACM. Kaplan-Meier analyses (KMA) were performed to compare overall survival (OS), noncancer-specific survival (NCS), and cancer-specific survival (CSS) between patients with non-elevated and elevated preoperative CRP and between patients without and with 30-day Clavien ≥3 complications. Results: A total of 2,234 patients were analyzed [116 (5.2%) experienced Clavien ≥3 complications; median follow up 44 months]. MVA revealed that coronary artery disease (OR 2.37, p=0.005), elevated CRP (OR 2.25, p=0.004), PN (OR 2.79, p<0.001), and open surgical approach (OR 1.74, p=0.049) were predictive of Clavien ≥3 complications. Additionally, MVA demonstrated that elevated CRP was an independent predictor of NCM (HR 2.50, p=0.009), CSM (HR 5.51, p<0.001) and ACM (HR 4.04, p<0.001), while presence of 30-day Clavien ≥3 complications was independently associated with worsened NCM (HR 3.05, p=0.042) but not CSM or ACM. KMA comparing non-elevated and elevated preoperative CRP revealed significant differences for 5-year OS (96.0% vs. 66.8%, p<0.001), 5-year CSS (98.2% vs. 75.6%, p<0.001), and 5-year NCS (97.6% vs. 87.7%, p<0.001). KMA comparing patients without and with 30-day Clavien ≥3 complications revealed significant differences for 5-year OS (87.3% vs. 80.7%, p=0.015) and 5-year NCS (95.6% vs. 87.0%, p<0.001), but not 5-year CSS (91.3% vs. 88.9%, p=0.601). Conclusions: In patients undergoing surgical resection for RCC, elevated preoperative CRP was an independent risk factor for development of 30-day Clavien ≥3 complications, while elevated CRP and development of Clavien ≥3 complications were associated with worsened NCM. Our findings suggest an interplay between major complications and NCM in patients who undergo surgery for RCC, with elevated preoperative CRP being a predictor for both.

Does presence of diabetes mellitus impact patient oncological outcomes in renal cell carcinoma: A multicenter analysis

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Background: Diabetes mellitus (DM) has been hypothesized to be a risk factor for development of renal cell carcinoma (RCC). We evaluated impact of DM on survival outcomes in RCC. Methods: We performed a retrospective analysis of the International Marker Consortium for Renal Cancer (INMARC). The cohort was divided into three subgroups (patients with stage I vs. stage II vs. stage III RCC) for descriptive, survival and multivariable analysis of outcomes. Kaplan Meier Analysis (KMA) was used to compare diabetic and non-diabetic patients in the different stage subgroups to evaluate overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS). Cox Regression multivariable analysis (MVA) was used to elucidate independent risk factors for all-cause mortality (ACM). Results: 2,927 patients with stage I RCC (709-DM/ 2218 non-DM), 2,513 with stage II RCC (688 DM/1825 non-DM) and 460 with stage 3 RCC (355 DM/ 105 non-DM) were analyzed. MVA revealed DMII having no impact on CSM (p=0.118) or PFS (p=0.316) across all stages. MVA for ACM revealed age (HR 1.026, p<0.001), male sex (HR=1.425, p<0.001), hypertension (HR=1.693, p <0.001) and tumor size (HR=1.064, p<0.001) as independent risk factors. KMA identified increased ACM in stage I (p<0.001) and stage III (p<0.001) RCC patients with non-DM compared to diabetic patients. Conclusions: Our findings suggest that DM may have impact on survival of in RCC, but this impact is mostly driven by non-oncologic, as opposed to oncologic effects. Further investigation is requisite.

Differences in CRP and De Ritis ratio predictive abilities of cancer specific survival between ethnic groups

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Background: Studies have discussed the prognostic use of C-reactive protein (CRP) and De Ritis ratio (AST/ALT or AAR) in the evaluation of renal malignant masses. Elevated pre-treatment CRP has been shown to be associated with non-cancer mortality. Additionally increased preoperative AAR has been found to be a prognostic factor for overall survival. With studies showing the ethnic disparities in mortality rate in certain underserved ethnic groups, there is a need for investigation into possible ethnic differences. Our aim is to evaluate the association between these elevated preoperative markers and all-cause mortality (ACM) and cancer specific mortality (CSM) among ethnic groups. Methods: Retrospective review of the International Marker Consortium for Renal Cancer (INMARC) was performed. Patients with renal malignancies who underwent partial or radical nephrectomy (PN, RN) were included. Patients were grouped according to ethnicity and African American (AA), White, Asian, and Hispanic ethnic groups were selected for descriptive, survival and multivariable analysis of outcomes. A Cox-regression multivariable analysis (MVA) was performed for each group. The primary outcome was overall survival and cancer specific survival from time of surgery to last follow-up, which was evaluated using Kaplan-Meyer Analysis (KMA). Results: A total of 4,810 patients were analyzed (627 AA, 2,344 White, 462 Hispanic, 1,094 Asian). Preoperative CRP and AAR were considered elevated if above 5 mg/L and 1.26, respectively. Descriptive analysis showed significant differences in age, diabetes mellitus status, hypertension status, tumor size, surgery type (PN vs. RN), preoperative CRP, preoperative AAR, ACM and CSM between ethnicities (p-value <0.001). MVA revealed elevated CRP to be predictive of ACM in AA (p<0.001, HR 2.830, 95% CI [1.728, 4.635]) and White (p<0.001, HR 2.933, 95% CI [2.272, 3.785]) patients. Elevated AAR was only predictive for all ACM in Asian (p=0.004, HR 2.546, 95% CI [1.358, 4.775]) patients. MVA showed similar results for CSM with elevated CRP found to be a significant independent risk factor for CSM in AA (p<0.001, HR 7.006, 95% CI [2.649, 18.531]) and White (p<0.001, HR 3.391, 95% CI [2.403, 4.784]) patients while elevated AAR is a significant independent risk factor for all CSM in Asian (p=0.041, HR 2.374, 95% CI [1.034, 5.448]) patients. KMA revealed statistically significant impact of elevated CRP on ACM and CSM in AA, White, and Asian patients (p<0.001). It also showed a statistically significant effect of elevated AAR in Asian patients (p<0.001). Conclusions: CRP has broad utilities in prognostic abilities for non-Asian ethnic sub-cohorts. However, AAR has predictive abilities in Asian patients. These results show the importance of using different lab markers for preoperative assessment in renal masses and the need for further research in ethnic differences in clinical presentation.

Impact of age on functional decline following radical nephrectomy: Analysis of the International Marker Consortium for Renal Cancer (INMARC)

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Background: Radical nephrectomy (RN) is a mainstay of management of localized renal cancer larger than 4 cm in size. RN is associated with renal functional decline, however impact of age on functional decline is unclear. We investigated impact of age on post RN function, focusing on decline to moderate and severe chronic kidney disease (CKD). Methods: This was a retrospective analysis of the International Marker Consortium for Renal Cancer (INMARC) registry of patients who underwent RN. Primary outcome was development of de novo CKD stage IIIB [estimated glomerular filtration rate (eGFR)<45 mL/min/1.73m2). Secondary outcomes included de novo CKD stage III (eGFR<60) and CKD Stage IV (eGFR>30). Patients clinical characteristics were stratified by age groups (<50, 50-70 and >70 years old). Multivariable logistic regression analysis (MVA) was utilized to identify risk factors with renal functional decline to different CKD stages. Kaplan-Meier analysis (KMA) was utilized to evaluate functional outcomes with respect to the different age groups. Results: Overall, 2,436 patients were analyzed (≤50 years, n=513; 50-70 years, n=1,344; >70, n=579; median follow up 31.9 months). On MVA, increasing age was independently associated with increased risk of development of CKD Stage IIIb [compared to ≤50 years (referent), 50-70 years, OR 3.35, p<0.001 and >70 years OR 7.7, p<0.001]. In addition, increasing BMI (OR 1.029, p=0.002), coronary artery disease (OR 1.70, p=0.01), diabetes mellitus (OR 1.37, p=0.029) and African American race (OR 1.6, p=0.01) were independent risk factors for CKD stage IIIb. Increasing age was also independently associated with an increased risk of development of CKD Stage III [compared to ≤50 years (referent), 50-70 years, OR 3.4 p<0.001 and >70 years OR 9.4, p<0.001]. Increasing BMI (OR 1.032, p=0.002) and coronary artery disease (OR 1.87, p=0.015) were also risk factors for CKD stage III. Age >70 years was independently associated with increased risk of development of CKD Stage IV [OR 1.96, p=0.027]. In addition, male (OR 1.49, p= 0.036), increasing BMI (OR 1.03, p=0.003), diabetes mellitus (OR 2.69, p <0.001), and African American race (OR 2.02, p=0.002) were risk factors for CKD stage IV. Kaplan-Meier Analyses demonstrated age associated declines in 5 year freedom from CKD Stage III (≤50 years 73.9%, 50-70 years 53.7%, and >70 years 37.06%, p<0.001), CKD Stage IIIb (age ≤50 years 92.7%, 50-70 years 71.8%, and >70 years 55.5%, p<0.001) and CKD Stage IV (age ≤50 years 93.7%, 50-70 years 89.8%, and >70 years 81.2%, p< 0.001). Conclusions: Increasing age is an independent risk factor for progressive and clinically significant renal functional decline after radical nephrectomy. Prioritization for nephron sparing management should be considered whenever safe and feasible in elderly patients to reduce potential risk of sequelae of functional decline.