Robotic partial nephrectomy for cystic renal masses: a comparative analysis of a matched-paired cohort

Long-Term Oncologic Outcomes of Off-Clamp Robotic Partial Nephrectomy for Cystic Renal Tumors: A Propensity Score Matched-Pair Comparison of Cystic versus Pure Clear Cell Carcinoma

Few data are available on survival outcomes of partial nephrectomy performed for cystic renal tumors. We present the first long-term oncological outcomes of cystic (cystRCC) versus pure clear cell renal cell carcinoma (ccRCC) in a propensity score-matched (PSM) analysis. Our "renal cancer" prospectively maintained database was queried for "cystRCC" or "ccRCC" and "off-clamp robotic partial nephrectomy" (off-C RPN). The two groups were compared for age, gender, tumor size, pT stage, and Fuhrman grade. A 1:3 PSM analysis was applied to reduce covariate imbalance to <10% and two homogeneous populations were generated. Student t- and Chi-square tests were used for continuous and categorical variables, respectively. Ten-year oncological outcomes were compared between the two cohorts using log-rank test. Univariable Cox regression analysis was used to identify predictors of disease progression after RPN. Out of 859 off-C RPNs included, 85 cases were cystRCC and 774 were ccRCC at histologic evaluation. After applying the PSM analysis, two cohorts were selected, including 64 cystRCC and 170 ccRCC. Comparable 10-year cancer-specific survival probability (95.3% versus 100%, p = 0.146) was found between the two cohorts. Conversely, 10-year disease-free survival probability (DFS) was less favorable for pure ccRCC than cystRCC (66.69% versus 90.1%, p = 0.035). At univariable regression analysis, ccRCC histology was the only independent predictor of DFS probability (HR 2.96 95% CI 1.03-8.47, p = 0.044). At the 10-year evaluation, cystRCC showed favorable oncological outcomes after off-C RPN. Pure clear cell variant histology displayed a higher rate of disease recurrence than cystic lesions.

Perioperative and oncological outcomes of robot-assisted laparoscopic partial nephrectomy for cystic and solid renal masses: Evidence from controlled trials

To evaluate the outcomes of robot-assisted partial nephrectomy (RAPN) for solid and cystic renal tumors. We systematically searched the Cochrane Library, PubMed, EMBASE, and Scopus databases up to March 2023. Review Manager 5.4 performed a pooled analysis of the data for random effects. Besides, sensitivity and subgroup analyses to explore heterogeneity, Newcastle-Ottawa scale, and GRADE to evaluate study quality and level of evidence. Five observational studies comprising 1353 patients (Cystic tumor: 183; Solid tumor: 1083) were included in this study. Compared to solid masses, cystic masses were associated with fewer major complications (odds ratio [OR] = 2.2; 95% confidence intervals [CI] = 1.17 to 4.13; p = 0.01). Additionally, no significant differences were observed between the two groups in terms of operative time, warm ischemia time, blood loss, hospital stay, intraoperative complications, postoperative complications, transfusion rate, postoperative estimated glomerular filtration rate (eGFR), eGFR preservation, positive surgical margin (PSM), recurrence, overall survival (OS), cancer-specific survival (CSS), recurrence-free survival (RFS) and trifecta achievement. RAPN can be performed in cystic renal tumors with perioperative, functional, and oncologic outcomes like those achievable in solid tumors. However, our findings need further validation in a large-sample prospective randomized study.

Comparison of partial nephrectomy and radical nephrectomy for cystic renal cell carcinoma: a SEER-based and retrospective study

Cystic renal cell carcinoma (cRCC) is uncommon and surgical indication remains controversial. We compared radical nephrectomy (RN) with partial nephrectomy (PN) in patients with cRCC using data from the Surveillance, Epidemiology and End Results (SEER) database and a retrospective cohort including 106 cRCC patients hospitalized in Ruijin and Renji Hospitals from 2013 to 2022. The baseline characteristics between RN and PN groups in both cohorts were adjusted by propensity score-matching (PSM). A total of 640 patients were included in the SEER cohort. Before PSM, PN group in the SEER cohort had a lower level of T stage (p < 0.001) and comprised more Caucasians (p < 0.001). After PSM, RN was associated with worse overall survival (p < 0.001) and cancer-specific survival (p = 0.006) in contrast to PN. In the Chinese cohort, 86 patients who underwent PN and 20 patients who underwent RN were finally included. The mean proportions of estimated glomerular filtration rate preserved after RN were worse than PN. Therefore, PN should be preferred in cRCC patients.

Perioperative, oncologic, and functional outcomes of robot-assisted partial nephrectomy for special types of renal tumors (hilar, endophytic, or cystic): an evidence-based analysis of comparative outcomes

Purpose

This study aims to perform a pooled analysis to compare the outcomes of robot-assisted partial nephrectomy (RAPN) between complex tumors (hilar, endophytic, or cystic) and non-complex tumors (nonhilar, exophytic, or solid) and evaluate the effects of renal tumor complexity on outcomes in patients undergoing RAPN.

Methods

Four databases were systematically searched, including Science, PubMed, Web of Science, and Cochrane Library, to identify relevant studies published in English up to December 2022. Review Manager 5.4 was used for statistical analyses and calculations. The study was registered with PROSPERO (Registration number: CRD42023394792).

Results

In total, 14 comparative trials, including 3758 patients were enrolled. Compared to non-complex tumors, complex tumors were associated with a significantly longer warm ischemia time (WMD 3.67 min, 95% CI 1.78, 5.57; p = 0.0001), more blood loss (WMD 22.84 mL, 95% CI 2.31, 43.37; p = 0.03), and a higher rate of major complications (OR 2.35, 95% CI 1.50, 3.67; p = 0.0002). However, no statistically significant differences were found between the two groups in operative time, length of stay, transfusion rates, conversion to open nephrectomy and radical nephrectomy rates, estimated glomerular filtration rate (eGFR) decline, intraoperative complication, overall complication, positive surgical margins (PSM), local recurrence, and trifecta achievement.

Conclusions

RAPN can be a safe and effective procedure for complex tumors (hilar, endophytic, or cystic) and provides comparable functional and oncologic outcomes to non-complex tumors.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=394792, identifier CRD42023394792.

Implication of cystic fluid cytology of renal cell carcinoma on surgical practice

OBJECTIVES

To evaluate the incidence of positive cystic fluid cytology and its risk factors in cystic renal cell carcinoma (RCC) addressing its implication on the current surgical practice.

METHODS

All clinically diagnosed Bosniak III, IV cystic renal masses from March 2019 to August 2022 were studied prospectively. Database of patients' demographics and cystic tumor characteristics were recorded. Partial or radical nephrectomies were performed by either laparoscopic or robotic approach. Cystic fluid was collected right after specimen retrieval in the surgical field and examined by pathologist. Cytology results were compared to the demographic, perioperative variables using univariate and multivariate analysis.

RESULTS

A total of 70 patients of histologically confirmed cystic RCC were included. Sixty seven patients underwent radical nephrectomy with laparoscopic or robotic approaches, while 3 patients underwent radical nephrectomy. There was no intraoperative cystic rupture or fluid spillage. Positive cystic fluid cytology findings were identified in 34 (48.6%) patients, while negative cystic fluid cytology were identified in 36 (51.4%) cases. Definite malignant cells were observed in 28 patients while the other six patients showed highly suspicious atypical cells. Histologically, 24 (70.8%) patients were proven clear cell RCC and 25 (73%) showed Fuhrman grade 1 or 2 in final histologic review in positive group. Univariate and multivariate regression analysis between positive and negative cytology groups showed that the presence of the malignant cells in cystic fluid was significantly associated with patients' age (> 55 years) and Bosniak grade of cystic tumor (p < 0.05).

CONCLUSIONS

Definite malignant cells in cystic fluid cytology were observed through our study. Additionally, patients' age (> 55 years) and Bosniak grade were the significant risk factors of positive cytology in cystic RCC. Therefore, necessity of meticulous manipulation of cystic renal tumors, despite their clinical features, should not be underemphasized to avoid the least possible tumor cell seeding in case of cystic rupture when operating such high risk of positive cytology.

Surgical outcomes of robot-assisted laparoscopic partial nephrectomy for cystic renal cell carcinoma

To compare the surgical outcomes of robot-assisted partial nephrectomy (RAPN) between patients with cystic renal cell carcinoma (cRCC) and those with solid RCC (sRCC). We retrospectively analyzed 1065 patients who underwent RAPN between 2013 and 2020 for a pathological diagnosis of RCC. Patients were divided into two groups: cRCC and sRCC. cRCC was diagnosed according to the Bosniak classification system. To minimize selection bias between the two groups, patient variables (patient characteristics) and tumor factors (such as size and complexity) were adjusted using 1:1 propensity score matching. Of the 1065 patients, 94 (9%) were diagnosed with cRCC. Bosniak categories of IIF, III, and IV were noted in 4 (4.2%), 31 (33%), and 59 (63%) patients, respectively. After matching, 83 patients each were assigned to the cRCC and sRCC groups. The operation time in cRCC tended to be longer than in sRCC but not significantly different (164 vs. 150 min, P = 0.0767). Other surgical outcomes, such as change in estimated glomerular filtration rate ( - 5.2 vs.  - 7.2%, P = 0.1577), perioperative complications (14.5 vs. 15.7%, P = 0.9225), estimated blood loss (62 vs. 58 mL, P = 0.5613), or negative surgical margin status (100 vs 99%, P = 0.236), were not significantly different between the two groups. During the follow-up period of about 2 years, one and two patients showed recurrence in the cRCC and sRCC groups, respectively. The surgical outcomes of RAPN were similar between cRCC and sRCC, demonstrating the feasibility of RAPN for cRCC.

Perioperative outcomes in patients undergoing robot-assisted partial nephrectomy: Comparative assessments between complex and non-complex renal tumors

INTRODUCTION

The aim of this study was to investigate the effects of renal tumor complexity on perioperative outcomes in patients receiving robot-assisted partial nephrectomy (RAPN).

METHODS

This study included 153 consecutive patients with cT1 renal masses undergoing RAPN and analyzed their perioperative outcomes, particularly tumor complexity. In this series, cT1b, completely endophytic, hilar, and cystic tumors were considered complex tumors. Patients with tumors that met at least one of the complex criterion were placed in the complex tumor group; patients with tumors that did not meet any of the complex criteria were placed in the non-complex tumor group.

RESULTS

Of the 153 patients, 54 (35.3%) had complex tumors; specifically, 18 (11.8%) had cT1b tumors, 15 (9.8%) had completely endophytic tumors, 28 (18.3%) had hilar tumors, and 8 (5.2%) had cystic tumors. The non-complex group included 99 patients (64.7%). The complex tumor group had significantly longer warm ischemia and console times than the non-complex tumor group, but there was no significant difference between them in the achievement of the trifecta. Both warm ischemia and console times were significantly correlated with the number of complex factors. Multivariate analyses of complex factors demonstrated that completely endophytic and cT1b tumors were independently associated with warm ischemia time and console time, respectively.

CONCLUSIONS

For patients with complex tumors, RAPN may be a feasible procedure with acceptable perioperative outcomes. However, special attention should be paid to long warm ischemia and console times, particularly in those with completely endophytic and/or cT1b tumors.

Long-Term Functional and Oncologic Outcomes of Robot-Assisted Partial Nephrectomy for Cystic Renal Tumors: A Single-Center Retrospective Study

Objectives: To evaluate the outcomes of robot-assisted partial nephrectomy (RAPN) in cystic renal tumors. Materials and Methods: We retrospectively analyzed patients who underwent RAPN for either cystic (n = 46) or solid (n = 271) renal tumors at Fujita Health University between 2010 and 2019. Cystic renal tumors were diagnosed using cross-sectional imaging. Perioperative, oncologic, and functional outcomes were assessed. Results: The median follow-up periods were 38, 41, and 37 months in the total, cystic, and solid groups, respectively. Most patient characteristics were similar among both groups, while the median age of the cystic group was significantly lower than that of the solid group (p = 0.02). Most perioperative variables and complications were comparable between the two groups. There was no significant difference between the groups in perioperative renal function. The estimated glomerular filtration rate preservation rates were 93.1% and 89.2% in the cystic and solid groups, respectively (p = 0.17). The cystic group showed a higher benign histology rate (19.6% vs 7%) and lower Fuhrman grade than the solid group (24.3% vs 15.1% in grade 1, and 73% vs 81.3% in grade 2), although there was no statistically significant difference between the two groups. In the solid group, 10 patients (3.7%) experienced recurrence, and 2 patients (0.7%) died of renal-cell carcinoma, while none of the patients with cystic tumors experienced recurrence. There was no statistically significant difference between the cystic and solid tumors with respect to 5-year recurrence-free survival (p = 0.18), cancer-specific survival (p = 0.55), and overall survival (p = 0.35). Conclusions: RAPN for cystic renal tumors appears to be safe and feasible with perioperative, long-term functional and oncologic outcomes comparable with those in solid tumors. RAPN can be a safe and effective surgical option for cystic renal tumors.

Risk factors for intraoperative cyst rupture in partial nephrectomy for cystic renal masses

PURPOSE

To determine the risk factors of intraoperative cyst rupture in partial nephrectomy (PN) for a cystic renal mass (CRM) and their effect on the prognosis of patients.

MATERIALS AND METHODS

Patients who underwent partial nephrectomy for CRMs from January 2009 to January 2015 were included. Uni/multivariate Logistic/Cox analysis and Kaplan-Meier analysis were performed.

RESULTS

A total of 174 patients were included in this study. There were 27 (15.5%) intraoperative cyst ruptures. The median follow-up time was 60 months. Multivariate logistic analysis showed that the E component (P = 0.018) and N component (P = 0.022) of the R.E.N.A.L. nephrometry score, Bosniak category III (P = 0.044), and surgeon's experience (P = 0.030) were risk factors associated with intraoperative cyst rupture in PN for CRMs. The 5-year recurrence-free survival (RFS), cancer-free survival (CFS) and overall survival (OS) were 92.7%, 90.32% and 94.4%, respectively, in 124 cases of malignant CRM. Kaplan-Meier analysis demonstrated that 5-year RFS and 5-year CFS in patients with cyst rupture was worse than those without cyst rupture (P = 0.006 and 0.003, respectively). Multivariate Cox analysis revealed that intraoperative cyst rupture was independent risk factor for 5-year RFS and 5-year CFS (P = 0.039 and 0.013, respectively). However, there was no significant difference in OS between the two groups (P = 0.275).

CONCLUSIONS

The prevalence of intraoperative cyst rupture is relatively high. Higher E and N scores, Bosniak category III, and lacking surgical experience (<20 cases) increase the risk of occurrence of intraoperative cyst rupture.

Intraoperative Cyst Rupture during Partial Nephrectomy for Cystic Renal Masses-Does it Increase the Risk of Recurrence?

PURPOSE

Our objective was to assess the prevalence of intraoperative cyst rupture and its impact on oncologic outcomes.

MATERIALS AND METHODS

All patients who underwent partial nephrectomy for a cystic renal mass via an open or robot-assisted approach at a total of 8 academic institutions were included in this retrospective study. All operative reports were carefully reviewed and any description of cyst rupture, cyst effraction or local spillage intraoperatively was recorded as cyst rupture. Multivariate logistic regression analysis was done to assess the variables associated with cyst rupture. Recurrence-free, cancer specific and overall survival was estimated by the Kaplan-Meier method and compared with the log rank test.

RESULTS

Overall 268 patients were included in study. There were 50 intraoperative cyst ruptures (18.7%) in the whole cohort. No preoperative parameter was significantly associated with a risk of intraoperative cyst rupture on univariate or multivariate analysis. Of the cystic renal masses 75% were malignant on the final pathology report. At a median followup of 32 months 5 patients (2.5%) had local recurrence while progression to metastasis was observed in 2%. There were no peritoneal carcinomatosis nor port site metastasis. There was also no local or metastatic recurrence in the subgroup with intraoperative cyst rupture. Estimated recurrence-free survival did not differ significantly between patients with vs without intraoperative cyst rupture at 100% vs 92.7% at 5 years (p = 0.20).

CONCLUSIONS

Intraoperative cyst rupture during partial nephrectomy is a relatively common occurrence but with few oncologic implications.

Robot-assisted partial nephrectomy: systematic review of functional results

PURPOSE OF REVIEW

Various ischemia type during partial nephrectomy for renal cell cancer (RCC) resulted in different postoperative functional outcomes. Our objective was to systematically review the contemporary literature on robot-assisted partial nephrectomy (RPN) and investigate the association of ischemia type and tumor complexity with postoperative functional outcomes of the operated kidney and overall.

RECENT FINDINGS

Forty-five of the 99 reports identified were selected for qualitative analysis. All included studies were observational and nonrandomized. Overall, we found that patients undergoing RPN with zero ischemia and selective artery clamping had a lower decrease in glomerular filtration rates of the operated kidney in comparison to both warm and cold ischemia. This association seems also to play a role in patients with bilateral kidneys harboring complex tumors.

SUMMARY

Zero ischemia and selective artery clamping provide the best functional outcomes following robotic partial nephrectomy. This seems to be of particular relevance in patients with single kidney or tumors of high complexity. Whether these changes are statistically or clinically significant cannot be determined within this systematic review.

Robot-assisted partial nephrectomy confers excellent long-term outcomes for the treatment of complex cystic renal tumors: Median follow up of 58 months

OBJECTIVES

To analyze long-term outcomes of robot-assisted partial nephrectomy for treatment of complex cystic renal tumors.

METHODS

We retrospectively analyzed the data of patients who underwent robot-assisted partial nephrectomy for cystic (n = 32) and solid (n = 263) renal masses at Severance Hospital, Seoul, Korea. The primary outcome was assessment of perioperative safety for cystic tumor. Secondary outcomes were evaluation of long-term oncological and functional results.

RESULTS

Patients' clinical and demographic characteristics were similar among both groups. The median follow up of cystic and solid masses were 58 and 46 months, respectively. Cystic masses were more likely to have low Fuhrman grade 1 and 2 (P = 0.03), and shorter operative time (P = 0.04) compared with solid masses. There was no statistically significant difference regarding warm ischemia time, estimated blood loss, trifecta achievement, length of hospital stay, complication rates and renal function preservation (P > 0.05) between groups. In the solid group, 12 patients (4.1%) recurred, and six patients (2%) died from metastatic renal cell carcinoma, whereas the patients in the cystic group did not have any local or distance recurrence, and the survival rates were 100%. The 5-year cancer-free survival (P = 0.77), cancer-specific survival (P = 0.65) and overall survival (P = 0.83) rates were similar between the groups.

CONCLUSION

Robot-assisted partial nephrectomy appears to be safe and feasible treatment for complex cystic renal masses. It confers excellent long-term oncological outcomes. Robot-assisted partial nephrectomy should be the treatment of choice for complex cysts whenever feasible.

Robot-assisted partial nephrectomy in cystic tumours: analysis of the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database

OBJECTIVE

To evaluate the outcomes of robot-assisted partial nephrectomy (RAPN) in cystic tumours, analysing a large, multi-institutional, retrospective series of RAPN, as limited data are available about the outcome of RAPN in cystic tumours.

PATIENTS AND METHODS

We evaluated 465 patients who received RAPN for either cystic or solid tumours from 2010 to 2013 and included in the multi-institutional, retrospective Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database. Univariable and multivariable linear and logistic regression models addressed the association of cystic tumours with perioperative outcomes.

RESULTS

In all, 54 (12%) tumours were cystic. Cystic tumours were associated with significantly lower operative time (t -3.9; P < 0.001), once adjusted for the effect of covariates, whereas blood loss and warm ischaemia time were similar. Postoperative any grade complications were recorded in 66 solid (16%) and nine cystic (17%) tumours (P = 0.08). In multivariable analysis, cystic tumours were not associated with a significantly lower risk of any grade postoperative complications [odds ratio (OR) 0.9; P = 0.8]. Similarly, presence of tumours with cystic features was not associated with a significantly different risk of high-grade postoperative complications (OR 2.2; P = 0.1). Prevalence of cancer histology and positive surgical margin rates were similar in cystic and solid tumours. Cystic tumours were not associated with significantly different postoperative estimated glomerular filtration rate (t 0.4; P = 0.7), once adjusted for the effect of covariates.

CONCLUSIONS

RAPN can be performed in cystic renal tumours with perioperative, pathological, and functional outcomes similar to those achievable in solid tumours.

[Management of cystic renal masses: Review of the literature]

INTRODUCTION

The expansion of renal cysts diagnosis in the population entails to learn how to properly identify and treat potentially malignant lesions. The aim of this review article is to discuss anatomical and pathological characteristics as well as treatment of cystic renal tumors.

METHOD

A literature review of Medline publications on renal cysts and cystic tumors was conducted. Prospective and retrospective studies in adults, and previous reviews were analyzed.

RESULTS

Bosniak classification of renal cysts is used worldwide among urologists and radiologists to categorize cystic lesions according to their potential malignancy. There is a 0, 15, 50 and 95 % chance of cancerous cells in Bosniak I, II, III, and IV, respectively. The most frequent pathology is renal cell carcinoma, usually low grade and low stage. Category IIF cysts (F for follow-up) have a 25 % chance of malignancy and require surveillance at 6 months and regularly for 5 years. The follow-up can be done with CT imaging, MRI or contrast enhanced ultrasonography. Cyst biopsy, which was not recommended for a long time, could prevent 40 % of unnecessary surgeries for benign lesions. Bosniak category I and II cysts can be treated if symptomatic, by sclerotherapy or laparoscopic deroofing of the cyst. Category III and IV lesions must be treated as malignant tumors with security margins.

CONCLUSION

Diagnosis and treatment of Bosniak category IIF renal cysts remain the primary challenge for physicians in cystic renal tumor management. Biopsies of renal cysts seem reliable, with no risk of malignant cell dissemination.