Objective: Significant developments occurred in the clinicalmanagement of acute lymphoblastic leukemia (ALL) in adults inrecent decades. However, treatment results are still not satisfactory,especially in routine practice. The objective of this study was toevaluate the general clinical features, treatment details, and outcomesof a large group of patients followed in multiple centers in Turkeywith a diagnosis of ALL.Materials and Methods: A retrospective analysis of the data ofpatients with ALL was made, the patients having been diagnosed andtreated between January 2003 and June 2017 by different protocols inthe hematology clinics of ten different centers. A total of 288 patients,aged between 17 and 76 years old, were included in the study. In thisretrospective multicenter analysis of patients with ALL, classificationof patients was performed based on treatment period, Philadelphiachromosome positivity, treatment regimen, and administration ofallogeneic hematopoietic stem cell transplantation (allo-HSCT).Results: The majority of cases were B-cell in origin, while 224 patientshad B-ALL and 64 of the patients had T-ALL. Median follow-upduration for all patients was 18.2 months (range: 0.03-161 months).Philadelphia chromosome positivity was determined in 49 patients(21.9%), and 54 patients (18.8%) were receiving allo-HSCT. Afterinduction chemotherapy, 219 patients (76.0%) achieved complete remission, 32 patients (11.2%) were evaluated as treatment refractory,and 37 patients (12.8%) were deceased. Median overall survivalwas 47.7 months (95% confidence interval: 36.1-59.2) and mediandisease-free survival was 23.4 months (95% confidence interval: 6.7-40.0) for all patients.Conclusion: Multicenter studies are extremely important for definingthe specific clinical features of a particular disease. The results of thisstudy will make a significant contribution to the literature as theyreflect real-life data providing valuable information about the TurkishALL patient profile.