This phase II trial studies how well efatutazone dihydrochloride works in treating patients with previously treated myxoid liposarcoma that cannot be removed by surgery. Drugs used in chemotherapy, such as efatutazone dihydrochloride, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading.

PRIMARY OBJECTIVES:

I. To determine the confirmed response rate for efatutazone dihydrochloride (efatutazone) in patients with advanced myxoid liposarcoma whose disease has progressed on at least one prior therapy.

SECONDARY OBJECTIVES:

I. To assess the progression free survival (PFS), overall survival (OS), and adverse event rates for efatutazone treated patients with advanced myxoid liposarcoma whose disease has progressed on at least one prior therapy.

TERTIARY OBJECTIVES:

I. To assess the predictive value of peroxisome proliferator-activated receptor (PPAR) and retinoid X receptors (RXR) tumor expression from archived patient tumor samples.

II. To assess the predictive value of the expression of PPARgamma-regulated markers of adipocytes differentiation.

III. To assess the predictive value of the expression of PPARgamma-regulated cell cycle proteins.

IV. To assess the effects of efatutazone treatment on serum adiponectin levels.

OUTLINE:

Patients receive efatutazone dihydrochloride orally (PO) twice daily (BID) continuously. Courses repeat every 21 days in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up every 12 weeks for 2 years and then every 6 months for up to 5 years.

• Patients must have a formalin-fixed, paraffin-embedded (FFPE) tumor block OR 1 representative hematoxylin and eosin (H&E) and 20 unstained myxoid liposarcoma tissue slides available for submission to central pathology review; this review is mandatory prior to registration to confirm eligibility

• Measurable disease

• Progression on at least one prior systemic chemotherapy for advanced, unresectable or metastatic disease; prior adjuvant or neoadjuvant therapy is not included as prior systemic chemotherapy unless treatment occurred within the 6 months prior to study enrollment

  • There is no limit to the number of prior lines of treatment a patient has received
  • No treatment with biologic therapy, immunotherapy, chemotherapy, investigational agent for malignancy, or radiation =< 28 days before study registration; no treatment with nitrosourea or mitomycin =< 42 days before study registration
  • Patients should have resolution of any toxic effects of prior therapy (except alopecia) to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, grade 1 or less

• No history of the following:

  • Class III or IV congestive heart failure (CHF)
  • Pericardial effusion =< 12 months (grade 3 or 4)
  • Pericardial involvement with tumor
  • Grade 2 or higher pleural effusion =< 6 months

• No symptomatic, untreated, or uncontrolled brain metastases present

• Not pregnant and not nursing; for women of childbearing potential only, a negative pregnancy test done =< 7 days prior to registration is required; a female of childbearing potential is a sexually mature female who:

  • Has not undergone a hysterectomy or bilateral oophorectomy; or
  • Has not been naturally postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in the preceding 12 consecutive months)

• Patients with diabetes mellitus requiring concurrent treatment with insulin or thiazolidinedione (TZD) oral agents are not eligible

• Patients with known hypersensitivity to any TZD oral agents are not eligible

• Eastern Cooperative Oncology Group (ECOG) performance status 0-2

• Absolute neutrophil count (ANC) >= 1,000/mm^3

• Platelet count >= 75,000/mm^3

• Creatinine =< 1.5 mg/dL x upper limits of normal (ULN) OR calculated (calc.) creatinine clearance >= 30 mL/min

• Bilirubin =< 1.5 x ULN; for subjects with liver metastases =< 3 x ULN is allowed

• Serum glutamic oxaloacetic transaminase (SGOT) (aspartate aminotransferase [AST]) and serum glutamate pyruvate transaminase (SGPT) (alanine aminotransferase [ALT]) =< 2.5 x ULN; for subjects with liver metastases, SGOT (AST) and SGPT (ALT) < 5 x the upper normal limit of institution's normal range is allowed

• Eligible patients must have histopathologically confirmed myxoid liposarcoma with confirmation of DDIT3 rearrangement