Muscadine Grape Skin Extract in Treating Patients With Malignancy That Is Metastatic or Cannot Be Removed by Surgery

Inclusion Criteria:

* Patients must have histologically confirmed malignancy that is metastatic or unresectable and have failed standard therapies
* Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation; should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately
* Ability to understand and the willingness to sign an Institutional Review Board (IRB)-approved informed consent document
* Eastern Cooperative Oncology Group (ECOG) performance status =\< 2
* Absolute neutrophil count \>= 1000/mcL
* Platelets \>= 50,000/mcL
* Total bilirubin within normal institutional limits
* Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase \[SGOT\]/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase \[SGPT\]) =\< 2.5 X institutional upper limit or normal
* Creatinine clearance \>= 40 mL/min
* Stable supplement usage for \> 2 weeks prior to starting and agrees not to change while on this study
* Life expectancy \> 3 months

Exclusion Criteria:

* Patients who have had chemotherapy or radiotherapy within 4 weeks (6 weeks for nitrosoureas or mitomycin C) prior to entering the study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier
* Patients may not be receiving any other investigational cancer-directed agents
* History of allergic reactions attributed to compounds of similar chemical or biologic composition to MGE
* Patients unable to take oral medications or those with history of malabsorption due to bowel resection
* Patients with uncontrolled diarrhea or persistent nausea/vomiting requiring daily antiemetic therapy for symptom management
* 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
* Pregnant women are excluded from this study; breastfeeding should be discontinued
* Patients with primary brain tumors are excluded