Utero-ovarian Transposition in Patients With Pelvic Malignancies Undergoing Whole Pelvic Radiotherapy

Inclusion Criteria: 1. Age: Women 18 - 40 years of age who wish to preserve their fertility. 2. Malignancy: Diagnosis of pelvic malignancies that require radiotherapy, including: 1. Colon and rectal cancer with tumors. 2. Anal cancer. 3. Other pelvic malignancies that require administration of WPXRT. 3. Desire for Fertility Preservation: The patient expresses a clear desire to preserve fertility and the ability to carry a pregnancy in the future. 4. Preoperative Ovarian Function: The patient must have normal ovarian function, demonstrated by specific hormonal values, including: 1. Follicle-Stimulating Hormone (FSH): \<10 IU/L 2. Luteinizing Hormone (LH): within normal reference range for reproductive age (typically 1.5-8 IU/L in the early follicular phase). 3. Anti-Müllerian Hormone (AMH): \>1 ng/mL 4. Estradiol (E2): within the normal range for the follicular phase (usually 30-120 pg/mL). 5. No Distant Metastasis: Absence of metastatic disease confirmed by imaging (CT, MRI, or PET scans). 6. Body Mass Index (BMI) \< 35. 7. Signed Informed Consent. Exclusion Criteria: 1. Advanced Cancer Stage: Patients with locally advanced or metastatic disease. 2. Significant Uterine Pathology: Presence of large uterine fibroids, adenomyosis, or other intrauterine pathologies that would complicate the procedure or future pregnancy. 3. Poor General Health or Comorbidities: Severe medical conditions that contraindicate surgical intervention, that include but not limited to: * Cardiovascular Disease: 1. Recent (within 6 months) myocardial infarction (MI). 2. Ejection fraction (EF): EF \<30%. 3. Uncontrolled hypertension: Systolic BP \>180 mmHg or Diastolic BP \>110 mmHg prior to surgery. 4. Severe aortic stenosis: Valve area \<1 cm² with symptomatic status. * Uncontrolled Diabetes Mellitus: 1. Hemoglobin A1c (HbA1c) \> 9% 2. Persistent fasting glucose \>250 mg/dL preoperatively despite optimization. * Severe Respiratory Diseases: 1. Forced expiratory volume (FEV1): \<50%. 2. Oxygen saturation: Resting SpO₂ \<88% on room air without supplemental oxygen. 3. CO2 retention: PaCO₂ \>50 mmHg. * Connective Tissue Disorders: 1. Severe systemic lupus erythematosus (SLE): Active lupus nephritis with GFR \<30 mL/min. 2. Scleroderma with severe pulmonary hypertension or FVC \<50% predicted. 3. Rheumatoid arthritis with severe cervical spine instability (atlantoaxial subluxation). * Severe Inflammatory Bowel Disease (IBD): 1. Severe Crohn's or ulcerative colitis flares with C-reactive protein (CRP) \>10 mg/L and hypoalbuminemia (Albumin \<2.5 g/dL). 2. Severe malnutrition: BMI \<18.5 kg/m² or Prealbumin \<10 mg/dL * Steroid dependency: 1. Chronic steroid use (\>20 mg prednisone daily) with no feasible taper pre-surgery. 4. Prior Pelvic Radiotherapy. 5. Prior history of systemic chemotherapy and immunotherapy that resulted in significant toxicity and residual deficit. 6. Pregnancy: Patients who are currently pregnant are excluded from consideration for uterine transposition. 7. Unsuitable for Ovarian Function Preservation: Women with signs of poor ovarian reserve, including: * FSH: \>10 IU/L * AMH: \<1 ng/mL * Estradiol: outside normal range. 8. Non-Candidate for Fertility: Patients with contraindications to future pregnancy, such as severe uterine abnormalities or significant risk for pregnancy-related complications. 9. Body Mass Index (BMI) ≥35. 10. Absence of One of the Gonadal Vessels. 11. Other unlisted conditions or diagnoses that, in the opinion of the primary investigator, render the patient an unsuitable candidate for uteroovarian transposition.