Adjusted Hospital Sentinel Lymph Node Positivity Rates in Melanoma: A Novel Potential Measure of Quality.
OBJECTIVE
Our objectives were to examine whether hospital characteristics are associated with lower- and higher-than-expected sentinel lymph node biopsy (SLNB) positivity rates and whether hospitals with lower- or higher-than-expected SLNB positivity rates have worse patient outcomes.


BACKGROUND
Surgeon and pathologist SLNB technical errors may lead to incorrect melanoma staging. A hospital's SLNB positivity rate may reflect its SLNB proficiency for melanoma, but this has never been investigated.


METHODS
Stage IA-III melanoma patients undergoing SLNB were identified from the National Cancer Data Base (2004-2010). Hospital-level SLNB positivity rates were adjusted for patient- and tumor factors. Hospitals were divided into terciles of adjusted SLNB positivity rates. Hospital characteristics (using multinomial logistic regression) and survival (using Cox modeling) were examined across terciles.


RESULTS
Of 33,639 SLNB patients (from 646 hospitals), 2916 (8.7%) had at least 1 positive lymph node. Hospitals with lower- (low tercile) and higher-than-expected (high tercile) SLNB positivity rates were more likely to be low-volume hospitals (low tercile: relative risk ratio (RRR) = 2.57, P = 0.002; high tercile: RRR = 2.3, P = 0.004) compared to hospitals with expected rates (middle tercile). Stage I patients treated at lower-than-expected SLNB positivity rate hospitals had worse 5-year survival than those treated at expected SLNB positivity rate hospitals (90.0% vs 91.9%, P = 0.014; hazard ratio = 1.28, 95% CI: 1.05-1.57); survival differences were not observed by SLNB positivity rates for stage II/III.


CONCLUSIONS
Adjusted hospital SLNB positivity rates varied widely. Surgery at hospitals with lower-than-expected SLNB positivity rates was associated with decreased survival. Hospital SLNB positivity rates may be a novel measure to confidentially report to hospitals for internal quality assessment.
*Northwestern Institute for Comparative Effectiveness Research (NICER) in Oncology, Robert H. Lurie Comprehensive Cancer Center, Chicago, IL †Surgical Oncology and Quality Improvement Center, Department of Surgery, Northwestern University, Feinberg School of Medicine, Chicago, IL ‡Department of Surgery, Massachusetts General Hospital, Boston, MA §Division of Research and Optimal Patient Care, American College of Surgeons, Chicago, IL ¶Department of Surgery, University of Chicago Pritzker School of Medicine, Chicago, IL ||Division of Hematology/Oncology, Department of Medicine, Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Feinberg School of Medicine, Chicago, IL **Cancer Programs, American College of Surgeons, Chicago, IL ††Department of Surgery, NorthShore University HealthSystem, Evanston, IL.
Christine V
CV
Kinnier
Jennifer L
JL
Paruch
Allison R
AR
Dahlke
Jeffrey D
JD
Wayne
Al B
AB
Benson
David P
DP
Winchester
Karl Y
KY
Bilimoria
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D005260:Female; D006761:Hospitals / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000473:pathology*; D008875:Middle Aged; D009367:Neoplasm Staging; D017063:Outcome Assessment, Health Care; D019984:Quality Indicators, Health Care / Q000706:statistics & numerical data*; D021701:Sentinel Lymph Node Biopsy / Q000592:standards / Q000706:statistics & numerical data*; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology*; D014481:United States