The impact of intraoperative bleeding on the risk of chronic kidney disease after nephron-sparing surgery

Long-term functional outcomes in patients undergoing radical nephrectomy for renal cell carcinoma and tumor thrombus

BACKGROUND

Up to 15% of patients with locally advanced renal cell carcinoma (RCC) harbors tumor thrombus (TT). In those cases, radical nephrectomy (RN) and thrombectomy represents the standard of care. We assessed the impact of TT on long-term functional and oncological outcomes in a large contemporary cohort.

METHODS

Within a prospective maintained database, 1207 patients undergoing RN for non-metastatic RCC between 2000 and 2021 at a single tertiary centre were identified. Of these, 172 (14%) harbored TT. Multivariable logistic regression analyses evaluated the impact of TT on the risk of postoperative acute kidney injury (AKI). Multivariable Poisson regression analyses estimated the risk of long-term chronic kidney disease (CKD). Kaplan Meier plots estimated disease-free survival and cancer specific survival. Multivariable Cox regression models assessed the main predictors of clinical progression (CP) and cancer specific mortality (CSM).

RESULTS

Patients with TT showed lower BMI (24 vs. 26 kg/m2) and preoperative Hb (11 vs. 14 g/mL; all-p < 0.05). Clinical tumor size was higher in patients with TT (9.6 vs. 6.5 cm; p < 0.001). After adjusting for potential confounders, the presence of TT was significantly associated with a higher risk of postoperative AKI (OR 2.03, 95% CI 1.49-3.6; p < 0.001) and long-term CKD (OR: 1.32, 95% CI 1.10-1.58; p < 0.01). Notably, patients with TT showed worse long-term oncological outcomes and TT was a predictor for CP (2.02, CI 95% 1.49-2.73, p < 0.001) and CSM (HR 1.61, CI 95% 1.04-2.49, p < 0.03).

CONCLUSIONS

The presence of TT in RCC patients represents a key risk factor for worse perioperative, as well as long-term renal function. Specifically, patients with TT harbor a significant and early estimated glomerular filtration rate (eGFR) decrease. However, despite TT patients show a greater eGFR decline after surgery, they retain acceptable renal function, which remains stable over time.

Risk factors and predictive model for acute kidney Injury Transition to acute kidney disease in patients following partial nephrectomy

PURPOSE

Acute kidney disease (AKD) is believed to be involved in the transition from acute kidney injury (AKI) to chronic kidney disease in general populations, but little is understood about this possibility among kidney surgical populations. This study aimed to elucidate the incidence of AKD after partial nephrectomy and risk factors that promote the AKI to AKD transition.

METHODS

From January 2010 to January 2020, this study retrospectively collected a dataset of consecutive patients with renal masses undergoing partial nephrectomy in 4 urological centers. Cox proportional regression analyses were adopted to identify risk factors that promoted the AKI to AKD transition. To avoid overfitting, the results were then verified by logistic least absolute shrinkage and selection operator (LASSO) regression. A nomogram was then constructed and validated for AKI to AKD transition prediction.

RESULTS

AKI and AKD occurred in 228 (21.4%) and 42 (3.9%) patients among a total of 1062 patients, respectively. In patients with AKI, multivariable Cox regression analysis and LASSO regression identified that age (HR 1.078, 1.029-1.112, p < 0.001), baseline eGFR (HR 1.015, 1.001-1.030, p < 0.001), RENAL score (HR1.612, 1.067-2.437, p = 0.023), ischemia time > 30 min (HR 7.284, 2.210-23.999, p = 0.001), and intraoperative blood loss > 300ml (HR 8.641, 2.751-27.171, p < 0.001) were risk factors for AKD transition. These five risk factors were then integrated into a nomogram. The nomogram showed excellent discrimination, calibration, and clinical net benefit ability.

CONCLUSION

Around 3.9% patients following partial nephrectomy would transit from AKI to AKD. Intraoperative blood loss and ischemia time need to be diminished to avoid on-going functional decline. Our nomogram can accurately predict the transition from AKI to AKD.

Risks and benefits of partial nephrectomy performed with limited or with zero ischaemia time

OBJECTIVE

To test the hypothesis that longer warm ischaemia time (WIT) might have a marginal impact on renal functional outcomes and might, in fact, reduce haemorrhagic risk intra-operatively.

PATIENTS AND METHODS

Data from 1140 patients treated with elective partial nephrectomy (PN) for a cT1-2 cN0 cM0 renal mass were prospectively collected. WIT was defined as the duration of clamping of the main renal artery with no refrigeration and was tested as a continuous variable. The primary outcome of the study was evaluation of the effect of WIT on renal function (estimated glomerular filtration rate [eGFR]) postoperatively, at 6 months and in the long term (measured between 1 and 5 years after surgery). The secondary outcome of the study was haemorrhagic risk, defined as estimated blood loss (EBL) or peri-operative transfusions. Multivariable linear, logistic and Cox regression analyses, accounting for age, Charlson comorbidity index, clinical size, preoperative eGFR and year of surgery, were used and the potential nonlinear relationship between WIT and the study outcomes was modelled using restricted cubic splines.

RESULTS

A total of 863 patients (76%) underwent PN with WIT and 277 (24%) without. The baseline median eGFR was 87.3 (68.8-99.2) mL/min/1.73m2 for the on-clamp population and 80.6 (63.2-95.2) mL/min/1.73m2  for the off-clamp population. The median duration of WIT was 17 (13-21) min. At multivariable analyses predicting renal function, longer WIT was associated with decreased postoperative eGFR (estimate: -0.21, 95% confidence interval [CI] -0.31; -0.11 [P < 0.001]). Conversely, no association between WIT and eGFR was recorded at 6-month or long-term follow-up (all P > 0.8). At multivariable analyses predicting haemorrhagic risk, clampless resection with no ischaemia time and PN with short WIT was associated with an increased EBL (estimate: -21.56, 95% CI -28.33; -14.79 [P < 0.001]) and peri-operative transfusion rate (estimate: -0.009, 95% CI -0.01; -0.003 [P = 0.002]). No association between WIT and positive surgical margin status was recorded (all P = 0.1).

CONCLUSION

Patients and clinicians should be aware that performing PN with very limited or even with zero WIT might increase bleeding and the need for peri-operative transfusion while not improving long-term renal function outcomes.

A comprehensive assessment of frailty status on surgical, functional and oncologic outcomes in patients treated with partial nephrectomy-A large, retrospective, single-center study

BACKGROUND

Partial nephrectomy (PN) is a challenging procedure, which can be associated with severe complications. In consequence, the search for accurate and independent indicators of unfavorable surgical outcomes appears warranted. We aimed at evaluating the impact of frailty status on surgical, functional and oncologic outcomes in patients undergoing PN for renal cell carcinoma (RCC).

METHODS

A retrospective, single-center study including 1,282 patients treated with PN for clinically localized cT1 RCC was performed. The modified Frailty Index (mFI) was used to assess preoperative frailty. Multivariable logistic, Poisson and linear regression analyses(MVA) tested the effect of frailty on complications, acute kidney injury(AKI), renal function decline after PN. Cumulative incidence and competing-risk analyses investigated survival outcomes.

RESULTS

Of 1,282 patients, 220 (17%) were frail. Overall, 982 (76%) vs. 123 (9.6%) vs. 171 (13%) patients underwent open vs. laparoscopic vs. robot-assisted PN. Median follow-up was 66 (IQR: 35-107) months. At MVA, frailty status predicted increased risk of complications [Odds ratio (OR): 1.46, 95%CI 1.17-1.84; P < 0.001]. Moreover, frail patients were at higher risk of postoperative AKI (OR: 1.95, 95%CI 1.13-3.35; P = 0.01). In frail patients, renal function permanently decreased over time (P = 0.01) without any renal function plateau or improvement during the follow-up, which were instead observed in the nonfrail cohort. At competing-risks analyses, frailty status predicted higher risk of other-cause mortality [Hazard ratio (HR): 1.67, 95%CI 1.05-2.66; P = 0.02], but not of cancer-specific mortality (P = 0.3).

CONCLUSIONS

Frailty status predicts higher risk of adverse surgical outcomes after PN. Moreover, greater renal function decline was observed in frail patients, compared with nonfrail patients. Finally, the risk of OCM significantly overcomes the risk of dying due to RCC in frail patients.

Risk Factors of Chronic Kidney Disease after Partial Nephrectomy

Background: In comparison with radical nephrectomy, partial nephrectomy (PN) is considered a better option for small renal mass surgery, because of optimal kidney tissue removal and parenchyma preservation. But there are patients with worsening postoperative renal function (RF) and chronic kidney disease (CKD) after PN. Therefore, the study aimed to evaluate and detect risk factors for CKD after PN.Materials and Methods. A prospective observational study was conducted, which consisted of 91 individuals who received PN with warm ischemia and an estimated preoperative glomerular filtration rate (eGFR) ≥ 60 ml/min/1.72m2 without pathologic albuminuria. Preoperative and intraoperative factors like intraoperative hypotension (IOH), blood loss, and resected part volume were analyzed.Results. At 6-month follow-up, 14 (15.4 %) patients experienced postoperative CKD. After 12 months of follow-up, 15 (16.5 %) patients had CKD. Patients with CKD had a lower preoperative eGFR than non-CKD group (69.0 vs 91.0 ml/min/1.72m2, p < 0.001), longer ischemia (20.0 vs 14.0, p = 0.002) and IOH time (40.0 (40.0; 47.5) vs 0.0 (0.0; 26.2) min, p < 0.001). Also, higher volumes of resected kidney part tumor and removed parenchyma with higher glomerulosclerosis amounts (73.3 % vs 14.5 %, p = 0.009) were found in CKD group. Estimated blood loss > 500 ml during PN was discovered to be the major risk factor for CKD development (OR 11.13, 95 % CI 1.88–65.92, p = 0.008). Furthermore, kidney resected part volume (OR 1.05, 95% CI 1.05-1.10, p = 0.033) and IOH time (OR 1.11, 95% CI 1.03-1.19, p = 0.005) were identified as risk factors for postoperative CKD. Conclusions. Patients after PN are at an increased risk of CKD development. Most commonly, postoperative CKD occurs in the first 6 months after PN and appears stable after 12 months of follow-up. Blood loss > 500 ml during PN, IOH and resected kidney volume can have an impact on postoperative RF and increase the risk of CKD.

How to improve outcome in nephron-sparing surgery: the impact of new techniques

PURPOSE OF REVIEW

Nephron-sparing partial nephrectomy is the state of the art for localized small renal mass and it is gaining attention also for more advanced cases. In the present narrative review, we discuss the new developments that have occurred in the advancement of this approach over the past few years.

RECENT FINDINGS

Off-clamp, selective/superselective clamp and early-unclamping techniques are safe and feasible approaches, with potentially superior functional outcomes, and noninferior complications rate and oncological outcomes, when compared with main artery clamping. Renorrhaphy must preserve the physiological vascularization of residual parenchyma. Running sutures, particularly using barbed wires, shorten the operating and ischemia times. A further advantage could derive from avoiding a double-layer suture. Transperitoneal robot-assisted partial nephrectomy (RAPN) and retroperitoneal RAPN can be considered equivalent in terms of perioperative morbidity, functional and oncologic outcomes, regardless of tumor's location, thus the choice of the approach should be driven by the surgeon's expertise. Future improvements should be introduced by the single-port robotic surgery, which seems to be safe and feasibly also in an off-clamp manner.

SUMMARY

Significant advances have recently been achieved in nephron-sparing surgery technique. However, future studies with standardized reporting of these new techniques are needed to assess the real impact of them on early and long-term functional outcomes.

The impact of sex and age on distribution of metastases in patients with renal cell carcinoma

BACKGROUND

Our objective was to investigate age and sex-related discrepancies on distribution of metastases in patients with metastatic renal cell carcinoma (RCC).

METHODS

Within the National Inpatient Sample database (2008-2015) we identified 9607 patients with metastatic RCC. Trend test and Chi-square test analyses were used to evaluate the relationship between age and site of metastases, according to sex.

RESULTS

Of 9607 patients with metastatic RCC, 6344 (65.9%) were men and 3263 (34.1%) were women. Thoracic, abdominal, bone and brain metastases were present in 51.1 vs. 52.8%, 42.6 vs. 44.3%, 29.9 vs. 29.2% and 8.6 vs. 8.8% of men vs. women, respectively. Increasing age was associated with decreasing rates of thoracic (from 55.5 to 48.5%) and brain (from 8.6 to 5.8%) metastases in men and with decreasing rates of abdominal (from 48.3 to 39.6%), bone (from 32.6 to 24.9%) and brain (from 8.8 to 5.4%) metastases in women. (all p < 0.05). Rates of concomitant metastatic sites also decreased with increasing age, from 57.1 to 50.8% in men and from 54.1 to 50.2% in women.

CONCLUSIONS

Important age and sex-related differences exist in the distribution of RCC metastases. The distribution of metastases is marginally different between sexes. Specifically, more advanced age is associated with lower rates of thoracic and brain metastases in men and with lower rates of abdominal, bone and brain metastases in women. Age and sex should be take into consideration into the staging management strategy, as well as into the follow-up strategy of patients with metastatic RCC.