The Utility of ICD-10 Code Z85.x Personal History of Malignant Neoplasm for Case Finding Purposes

Methodology: This Talking Paper provides summary points regarding the utility of ICD-10 code Z85.x (Personal History of Malignant Neoplasm) for malignant neoplasm case finding purposes. Comprehensive Ambulatory/Professional Encounter Record (CAPER) encounters and Standard Inpatient Data Record (SIDR) visits were extracted from 01 OCT 2016 - 12 MAR 2024 for all Tri-Service Beneficiaries. Results: The Z85.x codes were queried across all diagnostic positions (Diag 1 Diag 20). A majority of records with Z85.x (77 ) had no other cancer, follow-up, screening, nor therapy treatment codes, suggesting these codes are either entered regardless of the reason for the visit or entered in an inconsistent manner. Conclusion: While personal history of malignancy codes may be beneficial for identifying individuals with a history of cancer, analysis of administrative data reveals that these codes lack the specificity to count an incident cancer case and are inconsistently used by providers, making it difficult to accurately identify individuals who are disease free after treatment.