A Comparative CT Study Of The Effect Of Radiotherapy On The Treatment Of Oligometastatic Spinal Metastases Of NSCLC Patients

Objective:CT imaging changes of spinal oligometastatic tumor in 78 NSCLC patients after receiving radiotherapy were analyzed to evaluate the effect of radiotherapy on lesion mineralization and tumor volume.In addition,the pain relief effect of radiotherapy was evaluated by pain scale questionnaires and by the dosage of clinical pain relievers.Methods:By analyzing the radiotherapy protocols and the relevant imaging data of 78 patients with NSCLC spine metastasis collected from January 2014 to March 2018,we tried to identify the CT imaging characteristics of different types of vertebral metastases;we also recorded the CT value of the same vertebral body at similar position before and(1,3 and 6 months)after the radiotherapy to evaluate the effect of radiotherapy on the tumors.Specifically,CT images obtained before and6 months after the radiotherapy were transported to the radiotherapy planning system to quantify the lesion mineralization and the tumor volume change.The quantified data were then subjected to statistical analysis to see if there is any significant change.In addition,the dosage of clinical analgesic drug was monitored before and after radiotherapy;the effect of radiotherapy on pain relief was discussed based on the change of pain scores and the drug dosages after the treatment.Results:All patients completed the treatment and the CT imaging examination successfully.There is a total of 86 lesions in the 78 patients.The 86 lesions were sub-divided into NSCLC adenocarcinoma and squamous cell carcinoma.For NSCLC adenocarcinoma,there are 40 osteolytic lesions,10 mixed lesions and 6osteogenic lesions;For squamous cell carcinoma,there are 22 osteolytic lesions,8mixed lesions and 0 osteogenic lesions.By the site of metastasis,there are 42 thoracic metastases,34 lumbar metastases and 6 thoracolumbar metastases.For osteolytic and mixed adenocarcinoma metastases,CT values show no significant change 1 month after the radiotherapy but show significant change 3 or6 months month after the treatment;For osteogenic adenocarcinoma metastases,CT values show no significant change 1,3 or 6 months after the radiotherapy(P >0.05).All the osteolytic thoracolumbar metastases were evaluated by CT imaging 6months after the treatment.Results show CR 1 case,PR 25 cases,MR 29 cases,and NR 7 cases,with the total effective rate being 41.9%.CT-based mineralization evaluation for all osteolytic and mixed metastases 6months after the radiotherapy: For osteolytic adenocarcinoma metastases,the total effective rate is 95% in 80 patients receiving radiotherapy and bisphosphonates treatment;75.5% patients show mild mineralization.For mixed adenocarcinoma metastases,the total effective rate is 90%;70% patients show mild mineralization.For osteogenic squamous cell carcinoma,the total effective rate is 95.5%;81.8%patients show mild mineralization.For mixed squamous cell carcinoma,the total effective rate is 87.5%;75% patients show mild mineralization.Pain relief efficiency evaluation: 76 patients need oral pain relivers before the treatment.Among the 76 patients,65 patients reported reduced pain reliver use after the treatment,accounting for 85.5% of the total patients.After the treatment,7 patients(9.2% of total patients)stopped pain reliver use completely;42 patients(55.2% of total patients)reported reduced pain reliver use within the same grade;16 patients(21% of total patients)reported reduced pain reliver use to a lower grade.The analgesic rates of the bisphosphonate + radiotherapy group(groups B,C,and D)were 87.5%,88.4%,and 85%,respectively,significantly higher than the62.5% of the radiotherapy only group(group A);the effective rate were also higher than the radiotherapy only group(P < 0.05).The three different radiotherapy doses showed no statistically significant difference in terms of pain relief.Conclusion:The osteolytic and mixed thoracolumbar metastases develop mineralization to varying degrees after the radiotherapy and bisphosphonate combination therapy and advance over time.CT scan can effectively detect the mineralization effect of osteolytic and mixed thoracolumbar metastases after the radiotherapy and bisphosphonate combination therapy and could be employed for evaluating the therapeutic effect.Combing radiotherapy and the bisphosphonate achieve better analgesic rate than the radiotherapy alone,suggesting the combination therapy should be considered whenever possible during the treatment of oligometastases.