Delayed progression to dialysis with early and intensive management of predialysis chronic kidney disease: a case-based approach

Stereotactic Ablative Radiotherapy for ≥T1b Primary Renal Cell Carcinoma: A Report From the International Radiosurgery Oncology Consortium for Kidney (IROCK)

PURPOSE

Patients with larger (T1b, >4 cm) renal cell carcinoma (RCC) not suitable for surgery have few treatment options because thermal ablation is less effective in this setting. We hypothesize that SABR represents an effective, safe, and nephron-sparing alternative for large RCC.

METHODS AND MATERIALS

Individual patient data from 9 institutions in Germany, Australia, USA, Canada, and Japan were pooled. Patients with T1a tumors, M1 disease, and/or upper tract urothelial carcinoma were excluded. Demographics, treatment, oncologic, and renal function outcomes were assessed using descriptive statistics. Kaplan-Meier estimates and univariable and multivariable Cox proportional hazards regression were generated for oncologic outcomes.

RESULTS

Ninety-five patients were included. Median follow-up was 2.7 years. Median age was 76 years, median tumor diameter was 4.9 cm, and 81.1% had Eastern Cooperative Oncology Group performance status of 0 to 1 (or Karnofsky performance status ≥70%). In patients for whom operability details were reported, 77.6% were defined as inoperable as determined by the referring urologist. Mean baseline estimated glomerular filtration rate (eGFR) was 57.2 mL/min (mild-to-moderate dysfunction), with 30% of the cohort having moderate-to-severe dysfunction (eGFR <45mL/min). After SABR, eGFR decreased by 7.9 mL/min. Three patients (3.2%) required dialysis. Thirty-eight patients (40%) had a grade 1 to 2 toxicity. No grade 3 to 5 toxicities were reported. Cancer-specific survival, overall survival, and progression-free survival were 96.1%, 83.7%, and 81.0% at 2 years and 91.4%, 69.2%, 64.9% at 4 years, respectively. Local, distant, and any failure at 4 years were 2.9%, 11.1%, and 12.1% (cumulative incidence function with death as competing event). On multivariable analysis, increasing tumor size was associated with inferior cancer-specific survival (hazard ratio per 1 cm increase: 1.30; P < .001).

CONCLUSIONS

SABR for larger RCC in this older, largely medically inoperable cohort, demonstrated efficacy and tolerability and had modest impact on renal function. SABR appears to be a viable treatment option in this patient population.

Being Overweight Is Related to Faster Decline in Annual Glomerular Filtration Rate in Kidney Transplant

Few studies have examined the relationship between non-immunological factors and glomerular filtration rate (GFR) decline in kidney transplant. Correcting these factors in native kidneys slows the progression of chronic kidney disease. The aim of this study was to analyze the association between the control of non-immunological factors and the annual decline of GFR.

METHODS

A single-center, retrospective study was performed. We included 128 patients who received kidney transplants between 2000 and 2015, with at least 1-year post-transplant follow-up. Clinical records were reviewed. GFR was estimated by CKD-EPI. Three groups were defined according to the annual change in eGFR (ΔGFR 2016-1015): non-progressors (> -1 mL/min/1.73 m²), slow progressors (> -1 and < -5 mL/min/1.73 m²), and fast progressors (< -5 mL/min/1.73 m²). Percentage of achievement of KDIGO target was also analyzed.

RESULTS

The mean GFR was 62.5 mL/min/1.73 m². Glomerulonephritis was the most common cause of kidney failure (36%). When the fast progressor group was compared with the non-progressor group, they differed significantly in age-patients were younger (40 ± 12.3 vs 45 ± 13.1 years)-post-transplant body mass index (27.4 ± 5.6 vs 25.2 x ± 5.9 kg/m²), and serum uric acid, which was significantly higher (6.4 ± 1.7 vs 5.5 ± 1.58 mg/dL). There were no differences between the groups with regard to blood pressure, dyslipidemia, proteinuria, or venous bicarbonate. Target systolic blood pressure was achieved by 45% of patients. Biopsy-proven acute rejection was higher in the fast progression group, although this was not statistically significant (13 [24.5%] vs 8 [13.1%]).

CONCLUSIONS

High body mass index was associated with a faster decline in glomerular filtration rate in this study. Target blood pressure <140/90 mm Hg was achieved in less than 50% of cases.

Sevelamer carbonate: a review in hyperphosphataemia in adults with chronic kidney disease

Sevelamer carbonate (Renvela(®)), a buffered form of sevelamer hydrochloride (Renagel(®)), is an orally administered non-absorbed phosphate-binding anion exchange resin used in the treatment of hyperphosphataemia in chronic kidney disease (CKD). In the EU, sevelamer carbonate is approved in adult CKD patients who require dialysis and in those who do not require dialysis with serum phosphate levels ≥ 1.78 mmol/L, whereas in the USA sevelamer carbonate is approved in adult CKD patients who require dialysis. Sevelamer carbonate and sevelamer hydrochloride achieved similar reductions in serum phosphate levels in randomized comparative trials in patients with CKD receiving haemodialysis; sevelamer carbonate also reduced serum phosphate levels in noncomparative studies in CKD patients not requiring dialysis. The most common adverse events with sevelamer carbonate are gastrointestinal in nature. Sevelamer has pleiotropic effects, such as improving the serum lipid profile and attenuating endothelial and cardiovascular risk factors in CKD. All formulations of sevelamer have markedly higher acquisition costs than calcium-based phosphate binders. Cost-effectiveness analyses focusing specifically on sevelamer carbonate have not been conducted, and those based on clinical trial data with sevelamer hydrochloride have provided both favourable and unfavourable results compared with calcium-based phosphate binders, reflecting heterogeneity between modelled analyses in terms of data sources, assumptions, comparators, geographical regions, type of costs included and other factors. Although well-designed studies evaluating the impact of phosphate binders on hard clinical endpoints appear to be warranted, sevelamer carbonate may be particularly useful for the treatment of patients at risk of metabolic acidosis (offering advantages over sevelamer hydrochloride in this regard) and for individuals requiring treatment with a phosphate binding agent that does not contain aluminium or calcium.