Purpose: To analyze the rates of concordance in the diagnosis of various hematological malignancies among patients referred to a tertiary cancer center, comparing the referring diagnosis with the final diagnosis at the M.D. Anderson Cancer Center.
Patients and methods: This was a cross-sectional study analyzing the 409 patients referred to the M.D. Anderson Leukemia Service in 1995 in whom a bone marrow examination was performed by the referring physician and in whom this examination was repeated at our institution. We also analyzed 100 cases, including 84 of the 409 referred patients for whom the diagnostic outside bone marrow slide had been sent for review.
Results: The overall concordance rate was 73%. In 18% discordances were present and considered of major importance (affecting treatment and/or prognosis) while in 9% there were minor discordances. Major discordance rates were 2% for chronic lymphocytic leukemic leukemia and 5% for chronic myelogenous leukemia, but 29% for acute myelogenous leukemia (79 patients), 43% for acute promyelocytic leukemia (7 patients), 19% for acute lymphocytic leukemia (42 patients), 57% for hairy cell leukemia (7 patients), and 23% for the myelodysplastic syndromes (75 patients). The concordance rate was 76% in the 100 cases in which bone marrow specimens permitted comparison of the morphologic diagnosis made by M.D. Anderson and the referring physician using the same slide, with a rate of 75% in the acute leukemias as finally diagnosed at our institution.
Conclusion: Although in the majority of cases the referring physicians and the specialty service agreed on diagnosis, major discordance occurs in a significant number of cases, including highly treatable diseases such as acute promyelocystic leukemia and hairy cell leukemia.