Sorafenib in Treating Patients With Metastatic or Unresectable Solid Tumors, Multiple Myeloma, or Non-Hodgkin's Lymphoma With or Without Impaired Liver or Kidney Function

Inclusion Criteria:

* Patients must have cytologically or histologically confirmed tumors that are metastatic or unresectable and for which standard curative or palliative measures do not exist or are no longer effective; Patients with solid tumors, multiple myeloma, or non-Hodgkin's lymphoma are eligible
* Lesions that can be accurately measured in at least one dimension (longest diameter to be recorded) as ≥ 20 mm with conventional techniques or as ≥ 10 mm with spiral CT scan
* All other lesions, including small lesions (longest diameter \< 20 mm with conventional techniques or \< 10 mm with spiral CT scan) and truly nonmeasurable lesions; Lesions that are considered non-measurable include the following:

  * Bone lesions
  * Ascites
  * Pleural/pericardial effusion
  * Lymphangitis cutis/pulmonis
  * Abdominal masses that are not confirmed and followed by imaging techniques
  * Cystic lesions
* ≥ 4 weeks since major surgery
* ≥ 4 weeks since completion of radiation or chemotherapy except for ≥ 6 weeks for nitrosoureas, L-PAM or mitomycin-C
* ECOG Performance Status of 0-2
* Non-pregnant and non-nursing because the effects of BAY 43-9006 on the fetus/infant are unknown; in addition, women of child-bearing potential and men must agree to use an appropriate method of birth control throughout their participation in this study; appropriate methods of birth control include abstinence, oral contraceptives, implantable hormonal contraceptives (Norplant), or double barrier methods (diaphragm plus condom)
* No patients with uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, uncontrolled hypertension, or psychiatric illness/social situations that would limit compliance with study requirements
* No concomitant medications known to cause hepatic or renal toxicity, including anti-seizure medications, non-steroidal anti-inflammatory agents, and steroids
* No gastrointestinal tract disease resulting in an inability to take oral medication or a requirement for IV alimentation, prior surgical procedures affecting absorption, or active peptic ulcer disease
* No HIV-positive patients receiving combination anti-retroviral therapy because of possible pharmacokinetic interactions with BAY 43-9006; however, patients who are HIV+ but without AIDS defining diagnosis and not on combination anti-retroviral therapy are eligible
* No patients with evidence of biliary or renal obstruction; patients should be observed for at least one week after treatment (i.e. stents or drains) for biliary or renal obstruction to ensure their organ dysfunction has stabilized before registration to this protocol
* No current treatment with other investigational agents
* No evidence of bleeding diathesis
* No patients on therapeutic anticoagulation; prophylactic anticoagulation (i.e., low dose warfarin) of venous or arterial access devices is allowed provided that the requirements for PT, INR or PTT is met
* No treatment with cytochrome P450 enzyme-inducing antiepileptic drugs (phenytoin, carbamazepine or Phenobarbital), rifampin or St. John's wort
* Patients with brain metastases are eligible if they meet all of the following criteria:

  * Asymptomatic
  * Radiographically stable disease for at least 2 months
  * Previously received treatment for the brain metastases
  * Not currently receiving steroid therapy or enzyme-inducing anticonvulsants (e.g. phenytoin, phenobarbital, or carbamazepine)
* Granulocytes ≥ 1,500/μl
* Platelet count ≥ 75,000/μl
* Normal or abnormal organ function