MH-ART vs CF-IMRT in Postoperative Cervical/Endometrial Cancer

Inclusion Criteria: 1. Participants must be fully voluntary and have decision-making capacity, providing written informed consent within 30 days prior to enrollment. 2. Age ≥18 years and ≤75 years. 3. ECOG performance status of 0-1, and expected to tolerate lying supine for half an hour. 4. Have undergone radical surgery for cervical cancer (procedure: radical hysterectomy + pelvic lymphadenectomy ± para-aortic lymphadenectomy) or surgery for endometrial cancer (procedure: total hysterectomy + bilateral salpingo-oophorectomy ± pelvic and/or para-aortic lymph node dissection/sampling or sentinel lymph node biopsy). 5. For participants with cervical cancer, the following criteria must be met: (1)Pathologically diagnosed with cervical squamous cell carcinoma or adenocarcinoma. (2)Must have at least one of the following high-risk factors; or have other risk factors requiring postoperative radiotherapy: High-risk factors: Pelvic lymph node metastasis, or positive surgical margin, or parametrial invasion. Other risk factors: Middle or deep one-third stromal invasion, regardless of tumor size and LVSI status; Tumor size ≥4cm, regardless of depth of stromal invasion and LVSI status; Adenocarcinoma: Tumor size ≥2cm, or positive LVSI, regardless of depth of stromal invasion. 6.For participants with endometrial cancer, the following criteria must be met: Endometrioid adenocarcinoma: Grade 3 with superficial myometrial invasion, accompanied by substantial LVSI or age ≥70 years; Grade 2 with deep myometrial invasion, accompanied by substantial LVSI or age ≥60 years; Grade 3 with deep myometrial invasion; FIGO 2009 Stage II-IIIC1. Non-endometrioid adenocarcinoma: FIGO 2009 Stage I-IIIC1 (serous carcinoma, clear cell carcinoma, mixed type). 7.Participants with high-risk factors may receive a vaginal brachytherapy boost following the completion of external beam radiotherapy. 8.Participants with high-risk cervical cancer must receive concurrent sensitizing chemotherapy for ≥4 cycles. 9.Participants must be eligible to receive sequential or sandwich adjuvant chemotherapy as planned. Exclusion Criteria: 1. Presence of confirmed distant metastasis or para-aortic lymph node metastasis; 2. Requirement for extended-field radiotherapy encompassing the para-aortic region; 3. Initiation of radiotherapy exceeds the specified time limit after surgery: exceeding 6 months post-surgery if adjuvant chemotherapy was administered, or exceeding 3 months post-surgery if no adjuvant chemotherapy was administered; 4. History of previous abdominal or pelvic radiotherapy; 5. History of or concurrent secondary primary malignancy (except for non-melanoma skin cancer, papillary/follicular thyroid carcinoma, or carcinoma in situ of the breast); 6. History of underlying intestinal diseases such as ulcerative colitis or Crohn's disease; 7. Cervical cancer with pathological types such as adenosquamous carcinoma, small cell carcinoma, clear cell carcinoma, or other special types; Endometrial cancer with pathological types such as undifferentiated carcinoma, carcinosarcoma, or other special types; 8. Pregnant or lactating women; 9. Presence of active infection or fever; 10. Other severe comorbidities that may significantly compromise protocol compliance, such as uncontrolled cardiac disease requiring treatment, renal disease, chronic hepatitis, poorly controlled diabetes, psychiatric disorders, etc.