Brachytherapy (Iodine-125 Seeds) and Fluzoparib Combination Therapy for Advanced Unresectable Soft Tissue Sarcoma

Inclusion Criteria:

1. Voluntarily agree to participate in this study and sign an informed consent form;

2. Age ≥18 (calculated on the day of signing the informed consent), regardless ofgender;

3. Pathologically confirmed soft tissue sarcoma, with at least one measurable lesionaccording to RECIST 1.1 criteria on CT or MRI scan, within 28 days before the firststudy treatment (the longest diameter of the lesion ≥10 mm or the short diameter ofswollen lymph node ≥15 mm);

4. A single lesion ≤5cm and no more than 5 lesions;

5. Received systemic therapy (such as standard treatment: doxorubicin plus ifosfamide) ± surgical resection as the first-line treatment;

6. Able to swallow pills normally;

7. ECOG performance status of 0-1;

8. Expected survival period ≥12 weeks;

9. Normal function of important organs, including:

Absolute neutrophil count ≥1.5×109/L;Platelets ≥80×109/L;Hemoglobin ≥90 g/L;Serum albumin ≥28 g/L;Thyroid-stimulating hormone (TSH) ≤1×ULN (if abnormal, FT3 and FT4 levels should be examined simultaneously, and if FT3 and FT4 levels are normal, patients can be included);Bilirubin ≤1.5×ULN (within 7 days before the first treatment);ALT and AST ≤3×ULN (within 7 days before the first treatment);Alkaline phosphatase (AKP) ≤2.5×ULN;Serum creatinine ≤1.5×ULN; Non-surgically sterilized or fertile female patients need to use a medically recognized contraceptive measure (such as an intrauterine device, birth control pills, or condoms) during the study treatment period and within 3 months after the end of the study treatment. Fertile female patients who are not surgically sterilized must have a negative serum or urine HCG test within 72 hours before study enrollment and must not be breastfeeding. Male patients with fertile female partners should also use effective contraception during the trial period and for 3 months after the last dose of the study treatment.

Exclusion Criteria:

1. Clinical cardiac symptoms or disease that were not well controlled, such as: NYHAclass 2 or higher heart failure, unstable angina, myocardial infarction within 1year, clinically significant supraventricular or ventricular arrhythmias requiringtreatment or intervention, QTc>450ms (men); QTc>470ms (women);

2. Coagulation abnormal function (INR>2.0, PT>16s), bleeding tendency or onthrombolytic or anticoagulant therapy, prophylactic use of low-dose aspirin,low-molecular heparin allowed;

3. Clinically significant bleeding symptoms or clear bleeding tendency within 3 monthsprior to enrollment, such as daily cough/hemoptysis of 2.5 ml or more,gastrointestinal bleeding, esophagogastric fundic varices with bleeding risk ;

4. Arterial/venous thrombotic events such as cerebrovascular accidents (includingtemporary ischemic attack, cerebral hemorrhage, and cerebrovascular disease) thatoccurred within 6 months prior to enrollment. ischemic attack, cerebral hemorrhage,cerebral infarction), deep vein thrombosis and pulmonary embolism;

5. Known hereditary or acquired bleeding and thrombotic predisposition (e.g.,hemophiliacs, coagulation disorders, thrombocytopenia, etc.);

6. Patients who have received prior chemotherapy, surgery, less than 4 weeks aftercompletion of treatment (last dose) and prior to study dosing; or patients who havenot recovered from adverse events (other than alopecia) caused by prior treatment to ≤ CTCAE grade 1;

7. Patients with active infection, unexplained fever ≥38.5°C within 7 days prior todosing, or white blood cell count >15×109/L at baseline;

8. Patients with other malignancies (except cured basal cell carcinoma of the skin andcervical carcinoma in situ) within the previous 3 years or concurrently;

9. Patients with established bone metastases who have received, within 4 weeks prior toenrollment in the study;

10. Prior external radiotherapy to the lesion;

11. Pregnant or breastfeeding women, or women of childbearing age who do not wish to usecontraception;

12. Patients who, in the judgment of the investigator, have other factors that mayaffect the outcome of the study or force the termination of the study, such asalcoholism, substance abuse, other serious illnesses (including mental illness)requiring comorbid treatment, severe abnormal laboratory tests, accompanied byfamily or social factors that would affect the safety of the patient.