Editing Management of Localized and Locally Advanced Disease (section)

=== Partial nephrectomy (PN) ===

==== Advantages/Disadvantages ====
*'''<span style="color:#ff0000">Advantage (1):</span>'''
*# '''<span style="color:#ff0000">Preserved renal function compared to RN</span>'''
* '''<span style="color:#ff0000">Disadvantages</span>'''
*# '''<span style="color:#ff0000">Higher risk of blood transfusions and urologic complications (e.g. urine leak) than TA or RN</span>'''
*#* A small proportion of patients to additional treatments (e.g. ureteral stents, abdominal drains, embolization of pseudoaneurysm).
*# '''<span style="color:#ff0000">Potential for hyperfiltration renal injury</span>'''
*#* Patients who undergo nephron-sparing surgery for RCC may be left with a relatively small amount of renal tissue and are at risk for development of long-term renal functional impairment from hyperfiltration renal injury
*#** '''<span style="color:#ff0000">Proteinuria is the initial manifestation</span>'''
*#*** '''<span style="color:#ff0000">A 24-hour urinary protein measurement should be obtained yearly in patients with a solitary remnant kidney to screen for hyperfiltration nephropathy</span>'''
*#** '''<span style="color:#ff0000">Efforts to prevent or to ameliorate the damaging effects of hyperfiltration</span>''' have focused on dietary and pharmacologic interventions, primarily the use of '''<span style="color:#ff0000">ACE-inhibitors combined with a low-protein diet</span>'''

==== Indications ====

===== AUA =====
*'''<span style="color:#ff0000">[https://pubmed.ncbi.nlm.nih.gov/28479239/ 2021 AUA Guidelines on Renal Mass and Localized Renal Cancer]</span>'''
** '''<span style="color:#ff0000">Absolute (3):</span>'''
**# '''<span style="color:#ff0000">Anatomic or functionally solitary kidney</span>'''
**# '''<span style="color:#ff0000">Bilateral tumors</span>'''
**# '''<span style="color:#ff0000">Known familial RCC syndrome</span>'''
** '''<span style="color:#ff0000">Relative (4):</span>'''
**# '''<span style="color:#ff0000">cT1a renal masses (preferred over TA and RN)</span>''', not managed with active surveillance
**# '''<span style="color:#ff0000">Pre-existing CKD</span>'''
**# '''<span style="color:#ff0000">Pre-existing proteinuria</span>'''
**# '''<span style="color:#ff0000">Young age</span>'''
**# '''<span style="color:#ff0000">Multifocal masses</span>'''
**# '''<span style="color:#ff0000">Comorbidities that are likely to impact future renal function, including (4):</span>'''
**## '''<span style="color:#ff0000">Moderate to severe hypertension</span>'''
**## '''<span style="color:#ff0000">Diabetes mellitus</span>'''
**## '''<span style="color:#ff0000">Recurrent urolithiasis</span>'''
**## '''<span style="color:#ff0000">Morbid obesity</span>'''

==== Approach ====
* Can be done via open/laparoscopic/robotic approach
** Pure or robot-assisted laparoscopic PN should be done by experienced surgeons
*A minimally invasive approach should be considered when it would not compromise oncologic, functional, and perioperative outcomes.[https://pubmed.ncbi.nlm.nih.gov/28479239/]
*See [[Open Kidney Surgery|Open Kidney Surgery Chapter Notes]]
*See [[Robotic Partial Nephrectomy|Robotic Partial Nephrectomy Chapter Notes]]

==== Technique ====
* '''Renal function can be optimized by (2):'''
*#'''Optimizing nephron mass preservation'''
*##'''<span style="color:#ff0000">The number of preserved nephrons is the primary factor determining renal function after PN</span>'''
*#'''Avoiding prolonged ischemia'''
*##'''<span style="color:#ff0000">Ischemic injury plays a secondary role.</span>'''
*##* '''<span style="color:#ff0000">As long as the warm ischemic interval is limited (<25 minutes) or hypothermia is applied, most preserved nephrons will recover their function</span>'''
*##** Recovery from hypothermia is more consistent and reliable with intervals up to 60-90 minutes being well tolerated. Nevertheless, even with hypothermia it is best to avoid truly prolonged durations of ischemia
*'''The extent of normal parenchyma removed should be determined by surgeon discretion taking into account the clinical situation, tumor characteristics including growth pattern, and interface with normal tissue.'''
** Traditional PN is sharp excision with intentional removal of a modest rim of normal adjacent parenchyma
**Tumor enucleation refers to blunt excision of a tumor with minimal margin during nephron-sparing surgery
*** Originated in the familial RCC population as a technique to preserve renal parenchyma in patients with multiple tumors requiring multiple surgeries over a lifetime.
***'''<span style="color:#ff0000">To optimize parenchymal mass preservation, tumor enucleation should be considered in patients with:[https://pubmed.ncbi.nlm.nih.gov/28479239/]</span>'''
***# '''<span style="color:#ff0000">Familial RCC syndromes</span>'''
***#* '''Aggressive RCC syndromes, such as HLRCC, should be best managed with wide margin PN or RN.'''
***# '''<span style="color:#ff0000">Multifocal disease</span>'''
***# '''<span style="color:#ff0000">Severe CKD</span>'''
** '''<span style="color:#ff0000">Margin</span>'''
***'''<span style="color:#ff0000">Negative margin should be prioritized</span>'''
****While positive surgical margin during PN has not definitively been shown to adversely affect survival outcomes (recurrence-free, metastasis-free, cancer-specific, or overall survival), a negative surgical margin is always the goal
*****Cohort study of 1,344 PN patients from MSK found that compared to negative margins, positive margins was not associated with worse recurrence-free or metastasis-free survival. J Urol 2008.
***** Multi-centre cohort study of 775 patients from Europe found that compared to negative margins, positive margins was not associated with worse recurrence-free, cancer-specific, or overall-survival. Eur Urol 2010.
****'''<span style="color:#ff0000">Margin width is not important as long as final margins are negative.</span>'''
*** '''Management of positive surgical margins after PN or tumor enucleation'''
**** A variety of factors should be taken into account during counseling including the extent of the margin (microscopic versus extensive), tumor histology and grade, and other indicators of tumor biology such as locally invasive phenotype.
****'''In general, close surveillance is recommended in patients with a positive surgical margin'''
*** PN in patients with absolute indications should focus on preservation of renal parenchymal volume and functional nephrons with margin width being a less relevant consideration

==== Local recurrence in the remnant kidney after PN for RCC ====
* Occurs in 0-3% of patients
* '''Main risk factor is advanced T stage'''
* '''<span style="color:#ff0000">Most ipsilateral recurrences are distant from the tumor bed</span>''' and are therefore likely a result of unrecognized tumor multicentricity or de novo occurrence rather than true treatment failure
*Local recurrence rate after partial nephrectomy for pT1 with[https://link.springer.com/article/10.1007/s00345-022-04016-0]
**Negative margin: 0–1.5%
**Positive margin: 0-9%