Preliminary Clinical Study On¹²⁵I Seed Implantation In Treatment Of Recurrent Soft Tissue Sarcoma

Soft tissue sarcoma is a malignant tumor from mesenchymal tissue, theincidence rate is relatively low, which is a heterogeneous group of raremesenchymal tumours that account for roughly1%of all adult malignancies.Recently, the morbidity of soft tissue sarcoma is tend to be rising in USA andour country. Even though applying multi modality treatment, there still haveabout8%-20%local recurrence. Moreover the rate of treatment complicationis10%-30%. It is a difficult problem awaiting solution how to treat therecurrent soft tissue sarcoma effectively. Although the remedy for recurrencecan be surgical operation or secondary radiotherapy, patients can not bebenefit. Reserch suggested that the rate of amputation surgery is7%for thefirst treatment,38%for the recurrence patients, It can severely effect thepatients life quality. For the secondary radiotherapy patients, because the deathdose of sarcoma cell is80Gy, it is more farthen the tolerance dose of skin,musle and bone(TD/50), The dose is restricted by the limits of normal tissuesreceiving secondary radiotherapy, difficult to achieve the radical cure dose,lead to different level injury or organ dysfunctions, a decrease in quality of lifeand a increase in death rate. Eiber studied that the death risk of patients is3times as local recurrence treatment as primal treatment in2003, it suggestedthat local recurrence can increase the death risk.Radioactive¹²⁵I seeds interstitial implantation is a method ofbrachytherapy treatment. It is the implantation of radioactive¹²⁵I seeds into thetumor or the tissue invaded by tumor, Through its continuous γ-radiation, thetarget tumor cells have been killed, and can multiplied improve tumor targetdose by adjusting the space and activity of particle source. Meanwhile, thelimited the scope is5mm away from the seeds, make the surrounding havedropped steeply, and a small pathological damage. Thus the tumor target has high dose but on the surrounding normal tissue the damage is small, The targetarea receives high doses of anti-tumor effect To enhance the treatment effect,as well as to reduce the complications rates. The technique is feeble surgery,tissue damage is small, it is low pollution, easy to protect, also the¹²⁵I seedsinto implant the tumor or the tissue invaded by tumor, locating accurate, tumortarget has high dose but on the surrounding normal tissue the damage is small,thus it is most widely used, in abroad radioactive¹²⁵I seeds less apply for softtissue sarcoma, some researchs suggested that it have received obviouslyeffect in treatment of soft tissue sarcoma, in internal there only have some casereports, but there have no study about¹²⁵I seeds implantation in the treatmentof intermediate recurrent soft tissue sarcoma,and no research about life quliatyof¹²⁵I seeds implantation in the treatment of intermediate recurrent soft tissuesarcoma.In this study, with three-dimensional computer treatment planning system(TPS) and the CT and other precision positioning system,¹²⁵I seeds wasimplanted in local recurrent area which is unresectable and unsuitable forsecondary radiotherapy. There are preliminary observation on life qulity andefficacy, which can benefit to provide the clinical evidence of the feasibilityand the curative effect of¹²⁵I seeds implantation in this part.Objective: To study on the effect and safty on the treatment of recurrentsoft tissue sarcoma with¹²⁵I seeds interstitial implantation.Methods: To explore the clinical efficacy of recurrent malignant pelvictumors. We review the current status of type-B ultrasonic or CT guided¹²⁵Iseeds implantation in the treatment of10patientes of soft tissue sarcoma, Amedian of107.5(35-350) seeds were implanted into each lesion, median ofdose120Gy(80Gy-150Gy), active of each seed is18.5MBq-25.6MBq.Observe the life quality of patients,3-month local control rate and1-yearoverall survival rate after¹²⁵I seeds implantation.Results：The patients were followed up for a median of12months(3-26months). The consciousness, diet and sleeping of all patients were notdifferent improved in3days of¹²⁵I seeds interstitial implantation. But after1 week, all patients have different level improved in consciousness, diet andsleeping. There were significant differences in statistics on Kamofsky scorebetween before and after¹²⁵I seeds implantation(P=0.003), A median of20scores were improved. After1to7days cancer pain were relief,2patientsattained complete remission,2patients attain partial remission, the rate of painrelief was100%(4/4).3-month local control rate was80%,2patients wereobserved in tumor complete remission,6in partial remission,0in stabledisease,2in progressive disease.1-year survival rate was50%. All patientshave no a temperature, bleeding from the puncturatio position and the seedsdesquamation.8patients were observed redness of the skin (1grade) and lightcongestion and edema in mucosa (1grade). These changes returned to normalafter symptomatic treatment.2patients has occurred skin ulcer(3grade), thesechanges returned to normal after symptomatic treatment, but make the skinoccur pigmentation and scar. All patients have no radiation injury and¹²⁵Iseed–related complications such as fistura formation, infections of the skin,bone destroyed, muscular contraction, embolization.Conclusion：①¹²⁵I seeds interstitial implantation in treatment of recurrent softtissue sarcoma can improve life quality, relieve the cancer pain fast.â‘¡¹²⁵I seeds interstitial implantation in treatment of recurrent softtissue sarcoma is effective. It is an added method to cure soft tissue sarcomaand it is effective and safe.