Lymphoma diagnosis at an academic centre: rate of revision and impact on patient care.

Few studies have examined the value of a mandatory second review of outside pathology material for haematological malignancies. Therefore, we compared diagnoses on biopsies referred to an academic medical centre to determine the rate and therapeutic impact of revised diagnoses resulting from a second review. We reviewed 1010 cases referred for lymphoma during 2009-2010. For each case, referral diagnosis and second review diagnosis were compared. Revised diagnoses were grouped into major and minor discrepancies and all major discrepancies were reviewed by a haematologist to determine the effect the diagnostic change would have on therapy. There was no change in diagnosis in 861 (85·2%) cases. In 149 (14·8%) cases, second review resulted in major diagnostic change, of which 131 (12·9%) would have resulted in a therapeutic change. The highest rates of revision were for follicular, high-grade B-cell, and T-cell lymphomas. We found higher rates of major discrepancy in diagnoses from non-academic centres (15·8%) compared to academic centres (8·5%; P = 0·022), and in excisional biopsies (17·9%) compared to smaller biopsies (9·6%; P = 0·0003). Mandatory review of outside pathology material prior to treatment of patients for lymphoma will identify a significant number of misclassified cases with a major change in therapy.