de Oliveira Benigna Maria, Valadares Maria Thereza Macedo, Silva Marcilene Rezende, Viana Marcos Borato
Pediatrics Department, Faculdade de Medicina, Universidade Federal de Minas Gerais - UFMG, Belo Horizonte, MG, Brazil.
Rev Bras Hematol Hemoter. 2011;33(3):185-9. doi: 10.5581/1516-8484.20110051.
Remission rates achieved after the initial treatment of acute lymphoblastic leukemia may be similar in both developed and developing countries, but relapse rates are much higher in the latter. Thus, other reasons are needed, in addition to biological characteristics of the leukemic cells themselves, to explain the unfavorable evolution of patients living in unfavorable socioeconomic and cultural conditions.
The aim of this study was to retrospectively evaluate compliance to an acute lymphoblastic leukemia treatment protocol.
MAIN ABSTRACTED DATA WERE: total duration and reasons for interruption of chemotherapy, prescribed doses of 6-mercaptopurine, and median white blood cell and neutrophil counts during the maintenance phase. Interruptions of chemotherapy were considered inappropriate if they did not follow predetermined criteria established in the protocol.
Fourteen of 73 patients (19.2%) unduly interrupted chemotherapy by determination of their physicians. The median white blood cell count was higher when compared with the protocol recommendations; the median 6-MP dose was lower than the standard recommended dose. The estimated probability of event-free survival was higher for patients with lower median leukocyte counts and close to those predetermined by the protocol. Event-free survival was also higher for children with a higher percentage of days without chemotherapy due to bone marrow or liver toxicity excluding undue interruptions. In multivariate analysis, both factors remained statistically significant. These results suggest that the intensity of maintenance chemotherapy may not have been enough in some children, to achieve adequate myelosuppression, hence the observation of higher leukocyte counts and none or rare episodes of therapy interruption.
Compliance to the therapeutic protocol by both doctors and patients should always be considered in the evaluation of therapeutic failure in acute lymphoblastic leukemia; strict adherence to treatment protocols contributes to better treatment results in acute lymphoblastic leukemia children.
急性淋巴细胞白血病初始治疗后的缓解率在发达国家和发展中国家可能相似，但后者的复发率要高得多。因此，除了白血病细胞本身的生物学特性外，还需要其他原因来解释生活在不利社会经济和文化条件下患者的不良病情发展。
本研究的目的是回顾性评估对急性淋巴细胞白血病治疗方案的依从性。
主要提取的数据包括：化疗的总持续时间和中断原因、6-巯基嘌呤的规定剂量以及维持期的白细胞和中性粒细胞计数中位数。如果化疗中断不符合方案中规定的预定标准，则认为是不适当的。
73例患者中有14例（19.2%）经医生判定不恰当地中断了化疗。与方案建议相比，白细胞计数中位数更高；6-巯基嘌呤剂量中位数低于标准推荐剂量。白细胞计数中位数较低的患者无事件生存的估计概率更高，且接近方案预定值。因骨髓或肝脏毒性（不包括不当中断）而无化疗天数百分比更高的儿童无事件生存率也更高。在多变量分析中，这两个因素均保持统计学显著性。这些结果表明，在一些儿童中维持化疗强度可能不足，无法实现充分的骨髓抑制，因此观察到白细胞计数较高且无或很少有治疗中断事件。
在评估急性淋巴细胞白血病治疗失败时，应始终考虑医生和患者对治疗方案的依从性；严格遵守治疗方案有助于提高急性淋巴细胞白血病患儿的治疗效果。
