The Incidence and Outcome of Acute Lymphoblastic Leukemia in Shanghai, China Over 5 Years (2002–2006)

Great advances have been made in the diagnosis, molecular pathogenesis and treatment for acute lymphoblastic leukemia (ALL) in the past decade. Due to the lack of comprehensive population-based studies, the updated trend of incidence and geographic variations of ALL has not been well documented in Shanghai, China. To better understand the incidence and epidemiological features of ALL in Shanghai, we conducted a survey based on the database in the Center for Disease Control and the medical record in all hospitals in Shanghai, especially 28 major hospitals with hematology department. According to the CDC data, 544 patients with median age of 32y (1.2~89y) were diagnosed as de novo ALL during January 1, 2002 and December 31, 2006 and followed-up until December 31, 2007. The yearly incidence of ALL was (0.81±0.11)/100 000, which is slightly higher in men (0.86/100 000) than in women (0.75/100 000). The age-stratified incidence showed 2.31/100 000 in pts ≤17y, 0.54/100 000 in 18~34y, 0.46/100 000 in 35~59y, and 0.94/100 000 in pts > 60y. There were substantial geographic variations in the incidence of ALL, with 0.57±0.14/100 000 in Chongming county, an island eastern of Shanghai city, much lower than that of other districts in the central or around the central city, such as Qingpu, Baoshan, Hongkou, and Jiading districts (>0.9/100 000, P<0.05). Both FAB and WHO classification system were applied in the present study. Eighty-eight pts were diagnosed as L1 (26.2%), 193 L2 (57.4%), and 55 L3 (16.4%), For 302 pts with immunophenotyping data, 242 pts were identified as B cell orgin (80.1%), 59 T cell origin (19.5%), and 1 biphenotype (0.4%). The leukemia cells in 61 pts co-expressed one or two myeloid antigen (20.2%). For 269 pts with cytogenetics data, the incidence of t (9;22) in pts aged <10y, 11–17y, 18–44y, 45–59y and ≥60y were 4.2%, 11.4%, 19.2%,23.1% and 5.3%, respectively. For 473 evaluable pts, the complete remission (CR) rate and 3 year OS was 72.4% and (34.2±2.3)%, respectively. Both CR rates and 3 year OS decreased with age, 88.8% and (75.9±4.1%) in pts aged≤10, 87.3% and (36.8±6.8)% in 11–17y, 78.0% and (27.2±4.5)% in 18–44y, 73.5% and (16.1±4.7)% in 45–59y and 35.1% and (2.7±1.8)% in ≥60y (P<0.01). In this cohort of pts, only 26 received allogeneic hematopoietic stem cell transplantation (Allo-HSCT) in CR1. The probability of 3-year OS was 59.9±9.4%, better than those treated with conventional chemotherapy (36.3±8.0%) or auto-HSCT (33.3±17.2%, P<0.05). The age, WBC count at diagnosis, cytogenetic changes and donor availability are the factors influencing the prognosis.