Hydroxychloroquine and Temozolomide in Treating Patients With Metastatic or Unresectable Solid Tumors

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed solid tumor * Metastatic or unresectable disease * Refractory to standard therapy or no standard therapy exists * Measurable disease by RECIST criteria * Brain metastases allowed provided patient completed radiotherapy (if radiotherapy was clinically indicated at the time of diagnosis) AND discontinued steroids prior to study enrollment PATIENT CHARACTERISTICS: * ECOG performance status 0-1 * WBC ≥ 3,000/mm³ * Absolute granulocyte count ≥ 1,500/mm³ * Platelet count ≥ 100,000/mm³ * Serum creatinine ≤ 2.0 times upper limit of normal (ULN) * Total bilirubin ≤ 1.5 times ULN (\< 3.0 times ULN in the presence of Gilbert's disease) * AST and ALT ≤ 2.5 times ULN (≤ 5.0 times ULN in the presence of liver metastases) * aPTT normal * INR ≤ 1.5 (if on anticoagulation, INR must be \< 1.5 prior to starting anticoagulation) * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * HIV negative * No porphyria * No psoriasis, unless the disease is well controlled and patient is under the care of a specialist who agrees to monitor the patient for exacerbations * No previously documented macular degeneration or diabetic retinopathy * No concurrent serious illness including, but not limited to, any of the following: * Ongoing or active infection requiring parenteral antibiotics * Clinically significant cardiovascular disease (e.g., uncontrolled hypertension, myocardial infarction, or unstable angina) * New York Heart Association class II-IV congestive heart failure * Serious cardiac arrhythmia requiring medication * Peripheral vascular disease ≥ grade 2 within the past year * Psychiatric illness/social situation that would limit compliance with study requirements * No other concurrent malignancies, other than basal cell skin cancer, squamous cell skin cancer, carcinoma in situ of the cervix, or ductal or lobular carcinoma in situ of the breast PRIOR CONCURRENT THERAPY: * See Disease Characteristics * Recovered from all prior therapy * The following prior therapy is allowed in the adjuvant or metastatic disease setting: * Immunotherapy (interferon, aldesleukin, or sargramostim \[GM-CSF\]) * Chemotherapy, either as a single-agent or as combination therapy * Vaccine therapy * Targeted or biological therapy * Chloroquine derivatives * At least 4 weeks since prior active immunotherapy (aldesleukin, interferon, or ipilimumab) * At least 4 weeks since prior chemotherapy * At least 2 weeks since prior oral targeted therapies * More than 4 weeks since prior and no other concurrent investigational anticancer therapy (except for vaccines) * No prior temozolomide * Prior radiotherapy allowed * If radiotherapy has been administered to a lesion, there must be radiographic evidence of progression of that lesion in order for that lesion to constitute measurable disease or to be included in the measured target lesions * No concurrent cytochrome P450 enzyme-inducing antiepileptic drugs (phenytoin, carbamazepine, phenobarbital, primidone, or oxcarbazepine), rifampin, or Hypericum perforatum (St. John's wort) * No other concurrent anticancer therapy