ABSTRACT
Objectives
To evaluate the management, surgical outcomes, and pathological findings in patients
with tumor in a horseshoe-kidney (HK). HK patients present unique challenges due to
aberrant vascular anatomy and risk of renal insufficiency. We hypothesized that many
tumors in this setting may be indolent or benign.
Materials and Methods
Patients managed for renal mass in HK at our center (1999-2021) were reviewed. Baseline
characteristics, surgical approach, complications, functional outcomes, pathology,
and survival were analyzed.
Results
Forty-three procedures were performed in 42 patients with HK including 24 nephron-sparing
surgeries (NSS) and 19 radical nephrectomies (RN: splitting the isthmus and saving
the contralateral moiety). NSS included 22 partial nephrectomy (PN) and 2 thermal
ablations. Median tumor size was 4.3 cm. Eighteen cases (42%) were minimally-invasive,
17 open-midline, and 8 other open approaches. Ninety-day Clavien III-V complication
rate was 12% with no mortalities. For PN, median warm/cold ischemia times were 26/31
minutes, respectively. On pathology, only 27 tumors (63%) were renal-cell-carcinoma
(RCC), and 22 tumors (51%) were either benign (n = 10) or low grade, confined RCC (n = 12). Preoperative/new baseline/long-term eGFR were 82/83/78 mL/min/1.73 m2 after NSS vs 75/48/57 mL/min/1.73 m2 after RN, respectively. Long-term dialysis was required in 3 patients (7%). Median
follow-up was 36 months. Five-year recurrence-free survival was 83% for NSS and 66%
for RN.
Conclusions
Management of renal masses in HK is challenging and requires versatility with multiple
surgical approaches. Preservation of renal function was accomplished in most patients,
with a functional advantage observed for NSS. RCC was less common than expected while
benign and non-aggressive tumors were prevalent, suggesting consideration for preoperative
renal-mass-biopsy when feasible.
Abbreviations:
BMI (body mass index), EBL (estimated blood loss), eGFR (estimated glomerular filtration rate), HK (horseshoe kidney), IQR (interquartile range), MIS (minimally invasive surgery), NSS (nephron sparing surgery), PN (partial nephrectomy), RCC (renal cell carcinoma), R.E.N.A.L. ((R)adius (tumor size as maximal diameter), (E)xophytic/endophytic properties of tumor, (N)earness of tumor deepest portion to collecting system or sinus, (A)nterior (a)/posterior (p) descriptor, and (L)ocation relative to polar lines), RMB (renal mass biopsy), RFS (recurrence free survival), RN (radical nephrectomy), UC (urothelial carcinoma)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: April 08, 2022
Accepted:
March 6,
2022
Received:
January 31,
2022
Footnotes
Yosuke Yasuda and JJ Zhang contributed equally.
Financial Disclosure: The authors declare that they have no relevant financial interests.
Identification
Copyright
© 2022 Elsevier Inc. All rights reserved.
