Staged treatment for substantial bilateral calcium carbonate nephrolithiasis in vegan patient.

Calcium carbonate (CaCO3), or calcite, stones average 0.15% of annual nephrolithiasis cases. The authors report a 53 year old female, following a 15 year vegan diet, presenting with left flank pain and later found to have bilateral extensive staghorn renal calculi requiring multiple procedures over the course of months. Calcite stone formation is likely attributed to the patient's vegan diet and vitamin supplements. This stone's formation increases with neutral or alkaline urinary pH in the presence of high levels of magnesium. The authors discuss staged surgical treatment plans and non-surgical management prophylaxis with surgery as another possible route for treatment.

Does Reduced Renal Function Predispose to Cancer-specific Mortality from Renal Cell Carcinoma?

BACKGROUND: Recent publications have reported an association between increased renal cancer-specific mortality (CSM) and reduced renal function "below safety limits," and advocated for partial nephrectomy (PN) even for potentially aggressive/complex tumors. We hypothesize that this association may be related to confounding factors rather than a consequence of functional differences. OBJECTIVE: To assess whether there is an independent association between preoperative estimated glomerular filtration rate (eGFR) or new baseline eGFR (NB-GFR) and CSM in patients undergoing PN or radical nephrectomy (RN). DESIGN, SETTING, AND PARTICIPANTS: A single-center retrospective review was performed. All clinically and pathologically confirmed T1-T3a/N0/M0 renal cancer patients undergoing PN/RN (1999-2008, n = 1605) with adequate functional/oncological data were included. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was CSM. Secondary endpoints were cancer recurrence (CR) and all-cause mortality (ACM). Cox regression analyses investigated endpoints and predictive factors. RESULTS AND LIMITATIONS: The median age was 60 yr and 64% of patients were male. Comorbidities included hypertension (60%), cardiovascular disease (19%), diabetes (21%), and chronic kidney disease (22%). PN was performed in 954 patients (59%). The median preoperative eGFR and NB-GFR were 80 and 60 ml/min/1.73 m2, respectively. Median tumor diameter was 3.6 cm (interquartile range [IQR] = 2.4, 5.5); 70% of tumors were clear cell and 40% were of high grade. Pathology revealed pT1-2/N0/M0 and pT3a/N0/M0 in 81% and 19%, respectively. The median follow-up among survivors was 11.5 yr (IQR = 4, 14). Cancer-specific survival, recurrence-free survival, and overall survival were 94%, 88%, and 73% at 10 yr, respectively. On multivariable analysis, increased age (hazard ratio [HR] = 1.03, p = 0.04), increased tumor size (HR = 1.24, p < 0.01), tumor grade 3/4 (HR = 3.17, p < 0.01), and clear-cell histology (HR = 2.92, p < 0.01) were associated with increased hazard of CSM. Neither preoperative eGFR nor NB-GFR was significantly associated with CSM or CR (all p > 0.1), while an increased preoperative eGFR was associated with reduced hazard of ACM (HR = 0.87, p < 0.01). Limitations include retrospective design and a potential selection bias. CONCLUSIONS: Our data do not support oncological protection of greater preservation of renal function and confirm that unfavorable oncological outcomes for localized RCC are mostly associated with aggressive tumor characteristics. PATIENT SUMMARY: We did not find an association between greater preservation of renal function and oncological outcomes for kidney cancer.

Partial Nephrectomy for Patients with Severe Chronic Kidney Disease-Is It Worthwhile?

PURPOSE: Partial nephrectomy is prioritized over radical nephrectomy in patients with chronic kidney disease whenever feasible. However, we hypothesized that some patients with severe chronic kidney disease might rapidly progress to end stage renal disease, in which case the morbidity that can be associated with partial nephrectomy would not be justified. MATERIALS AND METHODS: A retrospective review of all 62 patients with stage IV chronic kidney disease undergoing partial nephrectomy at our institution (1999-2015) was performed. We analyzed preoperative/intraoperative factors and postoperative outcomes. Survival-analyses evaluated factors associated with time-to-progression to end stage renal disease the primary end point. RESULTS: Median age was 67 years, 71% of patients were male, and 84% Caucasian. Comorbidities included hypertension (94%), cardiovascular disease (53%) and diabetes (32%). Median preoperative estimated glomerular filtration rate was 23 ml/minute/1.73 m2 and 73% had an open approach. Benign pathology was found in 10 (16%) patients; only 23 (37%) and 7 (11%) patients had tumor grade 3/4 or pT3a disease, respectively. Unfavorable outcomes occurred in 15 patients (24%) defined as either 90-day mortality (3%), postoperative complication Clavien IIIb or greater (14%), or positive surgical margin (12%). Median time to progression to end stage renal disease was only 27 months (58 months for preoperative glomerular filtration rate greater than 25 ml/minute/1.73 m2 versus only 14 months when preoperative glomerular filtration rate was less than 20 ml/minute/1.73 m2). On multivariable analysis African American race (HR 2.55 [1.10-5.95]), preoperative estimated glomerular filtration rate 20 to 25 ml/minute/1.73 m2 or less than 20 ml/minute/1.73 m2 (HR 2.59 [1.16-5.84] and 5.03 [2.03-12.4], respectively) and minimally invasive approach (HR 2.05 [1.01-4.19]) were independently associated with progression to end stage renal disease. CONCLUSIONS: Our data suggest that some patients with stage IV chronic kidney disease undergoing partial nephrectomy have substantial comorbidities and nonaggressive pathology, and are at risk for unfavorable perioperative outcomes and rapid-progression to end stage renal disease. Renal mass biopsy should be strongly considered to improve patient-selection. Alternate strategies (active surveillance or radical nephrectomy) may be more appropriate, particularly when partial nephrectomy is high complexity or when the patient is African American, or preoperative glomerular filtration rate is less than 25 ml/minute/1.73 m2.

Split renal function in patients with renal masses: utility of parenchymal volume analysis vs nuclear renal scans.

OBJECTIVES: To evaluate the utility of parenchymal volume analysis (PVA) for estimation of split renal function (SRF) in patients with renal masses. SRF is important for deciding about partial vs radical nephrectomy (PN/RN) and assessing risk for developing severe chronic kidney disease after surgery. For renal donors PVA is routinely used to estimate SRF, but the utility of PVA for the more complex renal mass population remains undefined. PATIENTS AND METHODS: All patients (n = 374) with renal tumours and a normal contralateral kidney managed with PN (2010-2018), with preoperative/postoperative nuclear renal scans (NRS) and cross-sectional imaging were analysed. Parenchymal volumes were measured by free-hand scripting or software analysis. Concordance between ipsilateral estimated glomerular filtration rate (eGFR) values based on SRF from NRS vs PVA were evaluated by Pearson correlation and Bland-Altman plots. Parallel analysis of all 155 patients managed with RN at our centre (2006-2016) with preoperative NRS and imaging was also performed. RESULTS: For PN, the median age and tumour size were 62 years and 3.4 cm, respectively. The median preoperative ipsilateral parenchymal volume and eGFR were 181 cm3 and 36.9 mL/min/1.73 m2 , respectively. Parenchymal volumes estimated by free-hand scripting vs software analyses correlated strongly (r = 0.98, P < 0.001). Preoperative ipsilateral eGFR based on SRF from PVA vs NRS also correlated strongly (r = 0.94, P < 0.001). Ipsilateral eGFR saved after PN correlated strongly with parenchymal volume preserved (all r >0.60); however, the correlation was much stronger when ipsilateral eGFRs were based on SRF from PVA rather than NRS (z-statistic = 3.15, P = 0.002). For RN patients, preoperative eGFR in the contralateral kidney based on SRF from PVA vs NRS also correlated strongly (r = 0.87, P < 0.001). CONCLUSION: PVA has utility for estimation of SRF in patients with renal masses, even though this population is older and more comorbid than renal donors and the tumour can complicate the analysis. PVA can be obtained by software analysis from preoperative cross-sectional imaging and thus readily incorporated into routine clinical practice.

Palpable Penile Metastases: A Bizarre Presentation of Rectal Adenocarcinoma.

Metastasis to the penis is an uncommon occurrence, with only about 370 cases reported in the literature to date. The majority of the primary tumors are genitourinary in origin. We report on a patient with undiagnosed disseminated rectal adenocarcinoma, who first presented with lesions of the corporal bodies. A review of the literature indicates that corporeal metastasis as an initial presentation of malignancy is an extremely rare occurrence and carries a very poor prognosis.