Paclitaxel and Carboplatin With or Without Metformin Hydrochloride in Treating Patients With Stage III, IV, or Recurrent Endometrial Cancer

Inclusion Criteria:

* Patients must have measurable stage III, measurable stage IVA, stage IVB (with or without measurable disease) or recurrent (with or without measurable disease) endometrial carcinoma

  * Histologic confirmation of the original primary tumor is required; patients with the following histologic epithelial cell types are eligible:

    * Endometrioid adenocarcinoma, serous adenocarcinoma, undifferentiated carcinoma, clear cell adenocarcinoma, mixed epithelial carcinoma, adenocarcinoma not otherwise specified (N.O.S.)
* Measurable disease is defined by Response Evaluation Criteria in Solid Tumors (RECIST) (version 1.1); measurable disease is defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded); each lesion must be \>= 10 mm when measured by computed tomography (CT), magnetic resonance imaging (MRI) or caliper measurement by clinical exam; or \>= 20 mm when measured by chest x-ray; lymph nodes must be \>= 15 mm in short axis when measured by CT or MRI
* Patients must have a Gynecologic Oncology Group (GOG) performance status of 0, 1, or 2
* Absolute neutrophil count (ANC) greater than or equal to 1,500/mcl
* Platelets greater than or equal to 100,000/mcl
* Creatinine less than 1.4 mg/dl
* Bilirubin less than or equal to 1.5 x institutional/laboratory upper limit of normal (ULN)
* Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) less than or equal to 3 x ULN
* Alkaline phosphatase less than or equal to 2.5 x ULN
* Patients must NOT have received prior chemotherapy or targeted therapy, including chemotherapy used for radiation sensitization for treatment of endometrial carcinoma
* Patients may have received prior radiation therapy for treatment of endometrial carcinoma; prior radiation therapy may have included pelvic radiation therapy, extended field pelvic/para-aortic radiation therapy, and/or intravaginal brachytherapy; all radiation therapy must be completed at least 4 weeks prior to the first date of study therapy
* Patients may have received prior hormonal therapy for treatment of endometrial carcinoma; all hormonal therapy must be discontinued at least one week prior to the first date of study therapy
* Patients must be able to swallow and retain orally-administered medication
* Patients must have signed an approved informed consent and authorization permitting release of personal health information; individuals with impaired decision-making capacity are not eligible to participate on the study

Exclusion Criteria:

* Patients must NOT be taking metformin or have been on metformin in the past 6 months
* Patients with a history of other invasive malignancies, with the exception of non-melanoma skin cancer are excluded if there is any evidence of other malignancy being present within the last three years
* Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements
* Patients who are pregnant or nursing; if patients are of reproductive age and have not undergone hysterectomy, they must use an effective contraceptive method for the duration of this study
* Any condition associated with increased risk of metformin-associated lactic acidosis; (e.g. congestive heart failure defined as New York Heart Association \[NYHA\] class III or IV functional status, history of acidosis of any type; habitual intake of 3 or more alcoholic beverages per day)