Simple enucleation versus standard partial nephrectomy for clinical T1 renal masses: Perioperative outcomes based on a matched-pair comparison of 396 patients (RECORd project)

https://doi.org/10.1016/j.ejso.2014.01.007Get rights and content

Abstract

Objectives

To compare simple enucleation (SE) and standard partial nephrectomy (SPN) in terms of surgical results in a multicenter dataset (RECORd Project).

Materials and methods

patients treated with nephron sparing surgery (NSS) for clinical T1 renal tumors between January 2009 and January 2011 were evaluated. Overall, 198 patients who underwent SE were retrospectively matched to 198 patients who underwent SPN. The SPN and SE groups were compared regarding intraoperative, early post-operative and pathologic outcome variables. Multivariable analysis was applied to analyze predictors of positive surgical margin (PSM) status.

Results

SE was associated with similar WIT (18 vs 17.8 min), lower intraoperative blood loss (177 vs 221 cc, p = 0.02) and shorter operative time (121 vs 147 min; p < 0.0001). Surgical approach (laparoscopic vs. open), tumor size and type of indication (elective/relative vs absolute) were associated with WIT >20 min. The incidence of PSM was significantly lower in patients treated with SE (1.4% vs 6.9%; p = 0.02). At multivariable analysis, PSM was related to the surgical technique, with a 4.7-fold increased risk of PSM for SPN compared to SE. The incidence of overall, medical and surgical complications was similar between SE and SPN.

Conclusions

Type of NSS technique (SE vs SPN) adopted has a negligible impact on WIT and postoperative morbidity but SE seems protective against PSM occurrence.

Introduction

In the last decades, a net increase in the detection of small incidental renal masses has been observed and nephron-sparing surgery (NSS), aimed to preserve the largest amount of healthy renal tissue while obtaining similar oncologic outcomes of radical nephrectomy (RN), has become more popular.1, 2 Standard partial nephrectomy (SPN) consisting in the tumor removal with an adequate safety margin of health parenchyma is still considered as the gold standard technique.3 In the last decades, some Authors demonstrated that healthy parenchyma surrounding the tumor can be limited to a few millimeters without compromising the oncologic safety of partial nephrectomy (PN).4 Although the mean thickness of the safety margin surrounding the tumor ranges from 2.5 mm to 5 mm, some studies clearly demonstrated that the minimum values of thickness of the safety margin ranges between 0 mm and 1 mm above all at the bottom of the tumor.1 This variability of the thickness of the safety margin might be influenced by several anatomical and topographic tumor features. In this context, some Authors proposed the simple enucleation (SE) of the tumor as alternative to the SPN.5 This surgical procedure consists of a blunt dissection of the renal tumor following a plane between the capsule and the healthy renal tissue, without including any visible normal renal parenchyma. Recently, a multicenter, retrospective analysis reported similar cancer specific and recurrence free survival rates after SE and SPN.5 However, in the previous study no data concerning perioperative outcomes were reported. The objective of present study was to compare intraoperative and early post-operative outcomes observed in two recent cohort of patients who underwent SE or SPN for parenchymal renal masses.

Section snippets

Materials and methods

The Italian Registry of Conservative Renal Surgery (RECORd Project) is an observational multicenter prospectively derived dataset promoted by the Leading Urological No profit foundation Advanced research (LUNA) of the Italian Society of Urology. Patients who underwent open or laparoscopic PN for clinical T1 renal tumors between January 2009 and January 2011 at 19 urological Centers were collected in the registry and included into the study. The study was approved by the Internal Board Committee

Results

Overall, 198 patients that underwent SPN were matched with 198 patients that underwent SE. Demographics and tumors' characteristics are reported in Table 1. The two study groups were comparable in terms of: mean age, body mass index, gender, ECOG performance status, clinical tumor size, symptoms at diagnosis, type of indication, growth pattern, tumor location, glomerular filtration rate, hemoglobin level. The only difference that emerged between the two groups was the side of the tumor. Most

Comments

Recently, the interest for NSS has increased as several studies have demonstrated the oncologic equivalence with radical nephrectomy (RN) for the treatment of T1 RCC.14, 15 Various NSS techniques have been described. In 1950, Vermooten first suggested that peripheral renal tumors could be locally excised by leaving a margin of healthy parenchyma around the tumor of at least 1 cm.16, 17 Further studies have demonstrated that surgical margin involvement does not necessarily indicate residual

Conclusions

In a large multicenter prospectively derived dataset, SE is associated with shorter operative time and lower blood loss if compared to SPN. The two techniques are associated with similar WIT and similar incidence of overall, surgical and medical complications. The incidence of PSMs seems to be higher with SPN. The latter results need to be confirmed in further randomized studies aimed to minimize the possible confounding factors implied by a multicentre, observational study design.

Conflict of interest disclosure

Authors of this manuscript do not have any financial and personal relationships with other people or organisations that could inappropriately influence (bias) their work.

Funding

Unrestricted grant by the “Leading Urological No profit foundation Advanced research” (LUNA) of the Italian Society of Urology.

Abbreviations

NSS
Nephron-Sparing Surgery
RN
Radical Nephrectomy
SPN
Standard Partial Nephrectomy
SE
Simple Enucleation
RECORd
The Italian Registry of Conservative Renal Surgery
ECOG
Eastern Cooperative Oncology Group
WIT
Warm Ischemia Time
PSM
Positive Surgical Margin

References (29)

Cited by (0)

View full text