title: Miscoding of Melanoma Thickness in SEER: Research and Clinical Implications.
abstract: Melanoma-related deaths and metastases among patients with thin (≤1 mm) and ultrathin (≤0.25 mm) melanomas have been reported. These observations might reflect adverse biology and/or errors in administrative data. Cumulative melanoma-related death rates for thickness groups of patients with thin melanomas were compared among five cohorts including the Surveillance, Epidemiology, and End Results (SEER) registry. Thickness in one SEER region was reexamined in pathology reports. The 5-year cumulative melanoma-related death rate of patients with ultrathin melanomas was higher in SEER (2.8%) compared with other registries (0.6-0.9%). The rates across the 16 SEER regions were 0.25% to 8.4%. In SEER, 21% of thin melanomas were ultrathin; in other registries, they comprised 5.8-15%. A reexamination of thickness in one SEER site revealed that 114 of 447 ultrathin melanomas had errors; after correction, only 17 of the 114 remained ultrathin. The majority of errors were related to decimal point placement. The 86 thin melanomas reclassified to >1.00 mm included 96% of the original ultrathin-associated deaths and 100% of the original positive lymph nodes. Significant miscoding of thickness that is concentrated in ultrathin lesions is present in SEER and results in mischaracterization of patient outcomes. When using administrative data, validation of results can identify critical data issues.
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA. Electronic address: pgimotty@mail.med.upenn.edu.
authors.forename: Phyllis A
authors.initials: PA
authors.lastname: Gimotty
authors.affiliation: Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Shore
authors.affiliation: Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, USA.
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Lozon
authors.affiliation: Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, USA.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Whitlock
authors.affiliation: Department of Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Sidan
authors.initials: S
authors.lastname: He
authors.affiliation: Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, USA.
authors.forename: Fawn D
authors.initials: FD
authors.lastname: Vigneau
authors.affiliation: Division of Cancer Control and Population Science, National Cancer Institute, Rockville, Maryland, USA.
authors.forename: Lois
authors.initials: L
authors.lastname: Dickie
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Elder
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Xu
authors.affiliation: Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, USA.
authors.forename: Ann G
authors.initials: AG
authors.lastname: Schwartz
authors.affiliation: Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: DuPont
authors.initials: D
authors.lastname: Guerry
mesh_terms: D000328:Adult; D000368:Aged; D002423:Cause of Death / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008545:Melanoma / Q000453:epidemiology / Q000473:pathology*; D008875:Middle Aged; D011793:Queensland / Q000453:epidemiology; D012189:Retrospective Studies; D018426:SEER Program; D012720:Severity of Illness Index; D012867:Skin / Q000473:pathology*; D012878:Skin Neoplasms / Q000453:epidemiology / Q000473:pathology*; D015996:Survival Rate / Q000639:trends; D013548:Sweden / Q000453:epidemiology