ABSTRACT
The predictive value of HLA-DR and CD34 in the diagnosis of four distinct genetic entities of acute myeloid leukemia (AML) is presently not established. We evaluated the positive and negative predictive values (PPV and NPV, respectively), sensitivity, specificity, and correlation coefficients of HLA-DR and CD34 in AML pa-tients with t(15;17), t(8;21), inv(16), and abn(11q23). In AML with t(15;17) (n = 64), HLA-DR was expressed in 4.68% and CD34 was expressed in 15.62% and none of the cases expressed both HLA-DR and CD34. In AML with t(8;21) (n = 99), HLA-DR, CD34 or both antigens were expressed in the majority of cases (90.90%, 80.80%, and 79.79%, respectively). AML patients with inv(16) (n = 18) and abn(11q23) (n = 31) also highly expressed HLA-DR and CD34. Eight cases of t(8;21) and 1 case of abn(11q23) did not express either antigen. The highest corre-lation between CD34 and HLA-DR expression values was observed in cases with t(8;21) (r = 0.72) with the lowest correlation in inv(16) (r = 0.035). The PPV and NPV of HLA-DR-negativity plus CD34-negativity to predict t(15;17) was 85% and 100%, respectively, with 100% sensitivity and 92.74% specificity. The PPV and NPV of other mye-loid markers such as CD117, MPO and CD11c to diagnose t(15;17) were much lower than those of HLA-DR and CD34. It was concluded that the absence of double negativity of HLA-DR and CD34 strongly predicts against t(15;17). Rare HLA-DR-positive/CD34-negative cases exist in patients with t(15;17) and 8% of t(8;21) cases ex-pressed neither antigen. Further studies should determine whether HLA-DR-positive t(15;17) and HLA-DR-negative/CD34-negative t(8;21) represent a special entity associated with significant prognostic relevance.
ABSTRACT
Chronic lymphocytic leukemia (CLL), which is the most common leukemia in adult population in the Western world, is surprisingly rare in Thailand. The objective of our study was to retrospectively analyze the clinical presentations and outcome of a large cohort of Thai CLL patients diagnosed at a single institution in Bangkok, Thailand, from 1963-1998. One hundred and eighty-four patients were included in the study. The most frequent age group was 60-80 years old with the male to female ratio of 2:1. Only 12% of patients were younger than the age of 50. Most patients were from the central agricultural region of Thailand. Clinical findings at presentation included splenomegaly (64%), lymphadenopathy (60%), anemia (54%), hepatomegaly (49%), fatigue (39%), weight loss (33%), fever (21%), thrombocytopenia (18%), and anorexia (8%). Only 8% of Thai CLL patients were asymptomatic at presentation. The majority of patients were categorized as stages III and IV with the median survival of 20 months and 8 months, respectively. Infection was the most common cause of death, particularly in the elderly patients who had comorbid illnesses. Twenty-two percent of the patients had associated autoimmune disorders. The unfavorable prognostic factors observed were older age (> 70 years), weight loss and hepatosplenomegaly. We concluded that the age and gender of Thai CLL patients were similar to those of the Western countries but our patients came to medical attention at a later and more advanced stage. Prospective studies at a multi-center level in Thailand should be pursued to investigate further the genetic and epidemiologic nature of Thai CLL patients.