Association between renal mass biopsy and upstaging to perinephric fat involvement in a contemporary cohort of patients with clinical T1a renal cell carcinoma

Amirali Salmasi; Izak Faiena; Andrew T Lenis; Aydin Pooli; David C Johnson; Alexandra Drakaki; Kiran Gollapudi; Jeremy Blumberg; Allan J Pantuck; Karim Chamie

doi:10.1016/j.urolonc.2018.08.009

Association between renal mass biopsy and upstaging to perinephric fat involvement in a contemporary cohort of patients with clinical T1a renal cell carcinoma

Urol Oncol. 2018 Dec;36(12):527.e13-527.e19. doi: 10.1016/j.urolonc.2018.08.009. Epub 2018 Sep 15.

Authors

Affiliations

¹ Department of Urology, David Geffen School of Medicine at University of California, Los Angeles, CA; Institute of Urologic Oncology, David Geffen School of Medicine at University of California, Los Angeles, CA. Electronic address: asalmasi@mednet.ucla.edu.
² Department of Urology, David Geffen School of Medicine at University of California, Los Angeles, CA; Institute of Urologic Oncology, David Geffen School of Medicine at University of California, Los Angeles, CA.
³ Department of Urology, David Geffen School of Medicine at University of California, Los Angeles, CA.
⁴ Department of Urology, David Geffen School of Medicine at University of California, Los Angeles, CA; Institute of Urologic Oncology, David Geffen School of Medicine at University of California, Los Angeles, CA; Division of Hematology and Oncology, David Geffen School of Medicine at University of California, Los Angeles, CA.
⁵ Division of Urology, Department of Surgery, Harbor-UCLA Medical Center, Torrance, CA.

PMID: 30228094
DOI: 10.1016/j.urolonc.2018.08.009

Abstract

Background: Although tumor tract seeding from renal mass biopsy (RMB) is exceedingly rare, the possibility of tumor capsule violation from RMB leading to perinephric fat invasion has not been quantified. We evaluated the association between RMB and perinephric fat invasion in patients with clinical T1a renal cell carcinoma who underwent partial or radical nephrectomy.

Materials and methods: We reviewed the National Cancer Database from 2010-2013 and identified patients who underwent surgery for clinical T1a tumors. Patients were classified as upstaged only if final pathology demonstrated perinephric invasion only (pT3a). Mixed-effect logistic regression analysis was performed on inverse probability weighted matched groups to identify predictors of perinephric fat invasion. Multivariable Cox proportional hazards models and Kaplan-Meier survival curves were used to evaluate overall survival (OS).

Results: A total of 24,548 patients met our inclusion criteria. Pathologic upstaging to pT3a perinephric fat involvement occurred in 1.2% of patients. This rate of upstaging was 1.1% in the no biopsy group compared with 2.1% in patients who underwent RMB (P < 0.01). In multivariable logistic model, RMB was associated with pT3a perinephric fat upstaging (OR 1.69, 95% CI 1.17-2.44, P < 0.01). Upstaging to pT3a was also associated with worse OS (HR 1.71, 95% CI 1.13-2.60, P = 0.01). Kaplan-Meier survival curves demonstrated similar OS estimates in patients upstaged to pT3a disease, irrespective of undergoing RMB or not (Log-Rank = 0.87).

Conclusion: RMB was associated with increased rate of upstaging to pT3a perinephric fat involvement in clinical T1a RCC. This effect is small with unclear clinical significance. This is perhaps balanced by the importance of the information acquired from biopsies. Future studies are needed to elucidate clinical significance of this finding.

Keywords: Clinical T1a; Renal cell carcinoma; Renal mass biopsy; Small renal mass; Upstaging; pT3a disease.

MeSH terms

Adipose Tissue / pathology*
Aged
Biopsy
Carcinoma, Renal Cell / pathology
Carcinoma, Renal Cell / surgery*
Cohort Studies
Female
Follow-Up Studies
Humans
Kidney Neoplasms / pathology
Kidney Neoplasms / surgery*
Male
Nephrectomy*
Prognosis
Survival Rate