Chronic myelogenous leukemia in eastern Pennsylvania: an assessment of registry reporting

Chronic myelogenous leukemia (CML) has been reportable to the Pennsylvania Cancer Registry (PCR) since the 1980s, but the completeness of reporting is unknown. This study assessed CML reporting in eastern Pennsylvania where a cluster of another myeloproliferative neoplasm was previously identified.

Cases were identified from 2 sources: 1) PCR case reports for residents of Carbon, Luzerne, or Schuylkill County with International Classification of Diseases for Oncology, Third Edition (ICD-O-3) codes 9875 (CML, BCR-ABL+), 9863 (CML, NOS), and 9860 (myeloid leukemia) and date of diagnosis 2001-2009, and 2) review of billing records at hematology practices. Participants were interviewed and their medical records were reviewed by board-certified hematologists.

PCR reports included 99 cases coded 9875 or 9863 and 9 cases coded 9860; 2 additional cases were identified by review of billing records. Of the 110 identified cases, 93 were mailed consent forms, 23 consented, and 12 medical records were reviewed. Hematologists confirmed 11 of 12 reviewed cases as CML cases; all 11 confirmed cases were BCR/ABL positive, but only 1 was coded as positive (code 9875).

Very few unreported CML cases were identified, suggesting relatively complete reporting to the PCR. Cases reviewed were accurately diagnosed, but ICD-0-3 coding often did not reflect BCR-ABL-positive tests. Cancer registry abstracters should look for these test results and code accordingly.