Pelvic Radiation Therapy or Vaginal Implant Radiation Therapy, Paclitaxel, and Carboplatin in Treating Patients With High-Risk Stage I or Stage II Endometrial Cancer

Inclusion Criteria:

• To be considered eligible to participate in this trial, all patients must haveundergone hysterectomy; bilateral salpingo-oophorectomy (open or laparoscopicapproach) is strongly encouraged

• Peritoneal cytology should be obtained on entering the peritoneal cavity, as describedin the Gynecologic Oncology Group (GOG) Surgical Procedures Manual (https://gogmember.gog.org/manuals/pdf/surgman.pdf); pelvic and para-aorticlymphadenectomy are optional, but strongly encouraged (as staged patients enrolled onGOG-0210-molecular markers in endometrial carcinoma are eligible for this study)

• The procedures may be performed via laparotomy or laparoscopy (includingrobot-assisted) as per the surgeon?s preference; the surgeon must record in theoperative report whether a lymphadenectomy was performed (see link above toSurgical Procedures Manual) or not; a specific number of lymph nodes removed willnot be utilized for eligibility, but the operative report should reflect that theprocedure performed was consistent with the procedures described in the GOGSurgical Manual

• If either a bilateral salpingo-oophorectomy or nodal dissection was not performed,post-operative pre-treatment computed tomography (CT)/magnetic resonance imaging (MRI)is required and must not demonstrate evidence suggestive of metastatic disease (adnexa, nodes, intraperitoneal disease); post-operative, pre-treatment CT/MRI must beperformed if a pelvic and para-aortic nodal dissection was not performed

• For the purposes of description, patients will be staged according to theInternational Federation of Gynecology and Obstetrics (FIGO) 2009 staging system;eligibility is defined based on clinical-pathologic features; patients withendometrial carcinoma (endometrioid types) confined to the corpus uteri or withendocervical glandular involvement fitting one of the following high-intermediate riskfactor categories:

• Age >= 70 years with one risk factor

• Age >= 50 with 2 risk factors

• Age >= 18 years with 3 risk factors

• Risk factors: grade 2 or 3 tumor, (+) lymphovascular space invasion, outer ?myometrial invasion; patients with these risk criteria may be enrolled witheither positive or negative cytology

• Patients with stage II endometrial carcinoma (any histology) with cervical stromalinvasion (occult or gross involvement), with or without high-intermediate risk factors

• Patients with serous or clear cell histology (with or without other high-intermediaterisk factors) are eligible provided the disease is uterine-confined (with or withoutcervical stromal invasion or endocervical glandular involvement), and with peritonealcytology negative for malignancy

• Patients must have GOG performance status 0, 1, or 2

• Absolute neutrophil count (ANC) >= 1,500/mcl (equivalent to Common Toxicity Criteria [CTCAE version [v] 3.0] grade 1)

• Platelets >= 100,000/mcl (CTCAE v3.0 grade 0-1)

• Serum creatinine =< institutional upper limit normal (ULN), CTCAE v 3.0 grade 0

• Note: If serum creatinine > ULN, a 24-hour creatinine clearance must be collectedand must be > 50 mL/min

• Bilirubin =< 1.5 x ULN (CTCAE v3.0 grade 1)

• Serum glutamic oxaloacetic transaminase (SGOT) =< 2.5 x ULN (CTCAE grade 0-1)

• Alkaline phosphatase =< 2.5 x ULN (CTCAE grade 0-1)

• Neuropathy (sensory and motor) =< CTCAE v3.0 grade 1

• Patients who have met the pre-entry requirements; testing values/results must meeteligibility criteria

• Patients must have signed an approved informed consent and authorization permittingrelease of personal health information

Exclusion Criteria:

• Patients who have already received non-surgical therapy for endometrial cancerincluding chemotherapy, radiation (example, pre-operative or post-operativebrachytherapy), hormonal or biologic therapy

• Patients identified with pathologically confirmed spread of cancer beyond the uterusand cervix to pelvic or para-aortic lymph nodes, adnexal structures, and/or otheranatomic sites, or patients with serous or clear cell histology and with positivecytologic washings

• Patients with nodal (for patients who did not have nodal dissection performed) ordistant disease determined based on imaging studies; patients with suspicious nodesthat have been biopsied (re-staging operation, fine needle aspiration [FNA]) and arepathologically negative will be eligible

• Patients with a history of other invasive malignancies, with the exception ofnon-melanoma skin cancer, are excluded if there is any evidence of other malignancybeing present within the last 5 years; patients are excluded if their previous cancertreatment contraindicates this protocol therapy; specifically, patients who havereceived prior radiotherapy directed to treat disease within the abdominal cavity orpelvis are excluded

• Prior radiation of localized cancer of the breast, head and neck, thyroid, or skin ispermitted, provided that it was completed more than 5 years prior to registration, andthe patient remains free of recurrent or metastatic disease

• Patients may have received prior adjuvant chemotherapy for localized breast cancer,provided that it was completed more than 5 years prior to registration, and thepatient remains free of recurrent or metastatic disease

• Patients who have contraindications to pelvic radiation therapy (RT) (e.g. pelvickidney, connective tissue disease, inflammatory bowel disease, etc.) should bescreened in advance and not be considered eligible for the trial

• Patients with recurrent endometrial cancer

• Patients with surgical or clinical, FIGO 2009 stage III or IV endometrial carcinoma

• Patients with non-epithelial uterine malignancies such as uterine carcinosarcoma orleiomyosarcoma