肝脏转移灶立体定向放疗对恶性肿瘤患者外周血淋巴细胞计数的影响

Effect of stereotactic body radiotherapy for liver metastases on absolute lymphocyte count in patient with malignant tumors

目的探讨肝脏转移灶立体定向放疗(SBRT)对恶性肿瘤患者外周血淋巴细胞计数(ALC)的影响。方法选取2019年3月至2022年3月在自贡市第一人民医院接受肝脏转移灶SBRT的50例恶性肿瘤患者。患者肝脏转移灶接受的处方剂量为40~50 Gy/(4~13次),处方剂量的98%等剂量线覆盖计划靶区体积的90%以上,处方剂量的100%等剂量线覆盖内靶区或肿瘤区体积的100%,每周照射5次,每次治疗前使用锥形束CT以确保患者的摆位误差在许可范围。分别于放疗前1周、放疗后1周、1个月、3个月检测患者外周血ALC。比较不同放疗分割次数(≤5次和>5次)、单次剂量(≤10 Gy和>10 Gy)和生物等效剂量(BED)(<100 Gy和≥100 Gy)对患者ALC的影响。结果患者放疗前、放疗后1周、1个月、3个月外周血ALC分别为(1.72±0.43)×10^(9)/L、(1.24±0.38)×10^(9)/L、(1.36±0.41)×10^(9)/L、(1.75±0.39)×10^(9)/L,不同时间点外周血ALC比较差异有统计学意义(P<0.05)。放疗后1周、1个月外周血ALC均低于放疗前(均P<0.05),放疗后3个月外周血ALC逐渐恢复至放疗前水平(P>0.05);放疗后3个月外周血ALC均高于放疗后1周、1个月(均P<0.05)。放疗后1周、1个月,分割次数≤5次患者外周血ALC均高于分割次数>5次患者(均P<0.05),BED≥100 Gy患者外周血ALC均高于BED<100 Gy患者(均P<0.05)。而不同单次剂量患者不同时间点外周血ALC比较差异均无统计学意义(均P>0.05)。结论在肝脏转移灶SBRT治疗中,分割次数≤5次及BED≥100 Gy的SBRT可能更有利于防止发生外周血ALC减少。

Objective To investigate the effect of stereotactic body radiotherapy(SBRT)for liver metastases on absolute lymphocyte count(ALC)in patients with malignant tumors.Methods Fifty cancer patients with liver metastases receiving SBRT in Zigong First People's Hospital from March 2019 to March 2022 were enrolled in the study.Patients received a prescription dose of 40-50 Gy/(4-13 fractions)for liver metastases,with 98%isodose lines of the prescription dose covering more than 90%of the PTV volume and 100%isodose lines of the prescription dose covering 100%of the ITV or GTV volume.The irradiation schedule was 5 times per week,and the cone beam CT was used before each treatment to ensure the positional error within the permissible range.Peripheral blood ALC was measured 1 week before,and 1 week,1 month,3 months after radiotherapy,respectively.The effects of different radiotherapy fractions(≤5 and>5),single doses(≤10 Gy and>10 Gy),and biological effective dose(BED)(<100 Gy and≥100 Gy)on ALC were compared.Results The peripheral blood ALC of patients before,and 1 week,1 month,3 months after radiotherapy were(1.72±0.43)×10^(9)/L,(1.24±0.38)×10^(9)/L,(1.36±0.41)×10^(9)/L,(1.75±0.39)×10^(9)/L,respectively(P<0.05),the peripheral blood ALC was lower than that before radiotherapy at 1 week and 1 month after radiotherapy(both P<0.05),and the peripheral blood ALC gradually recovered to the level before radiotherapy at 3 months after radiotherapy(P>0.05),the peripheral blood ALC at 3 months after radiotherapy was higher than that at 1 week and 1 month after radiotherapy(both P<0.05).At 1 week and 1 month after radiotherapy,peripheral blood ALC was higher in patients with≤5 fractions than that in patients with>5 fractions(both P<0.05);and the peripheral blood ALC was higher in patients with BED≥100 Gy than that in patients with BED<100 Gy(both P<0.05).There was no significant difference in the peripheral blood ALC at different time points in patients with different single doses(all P>0.05).Conclusion In the treatment of cancer patients with liver metastases,SBRT with≤5 fractions and BED≥100 Gy may be more beneficial in reducing the incidence of peripheral blood ALC reduction.