• Subjects, \>= 18 years old, must have newly diagnosed or locally recurrent MDM2 or CDK4-amplified adipocytic sarcoma as determined by fluorescence in situ hybridization (FISH), or other clinically appropriate methodology in the opinion of the reviewing pathologist. Histologic or imaging evidence of the presence of a dedifferentiated component must be present

• Subjects must have one or more measurable target lesions by Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1), assessed via CT scan or MRI

• At the time of study enrollment, subjects must have a tumor burden that is judged to be surgically resectable

• Have plans to undergo neoadjuvant radiation therapy followed by surgical resection. Review and approval of final treatment plans for subjects receiving radiotherapy locally/at an outside institution must be reviewed and approved by a radiation oncologist investigator prior to initiation of radiotherapy

• Absolute neutrophil count (ANC) \>= 1500/mm\^3 (\>= 1.5 GI/L) without granulocyte colony-stimulating factor support in the last 14 days (subjects may not have received blood product transfusion or granulocyte colony-stimulating factor \[G-CSF\] within 14 days prior to screening)

• White blood cell count \>= 2500/mm\^3 (\>= 2.5 GI/L) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Platelets \>= 100,000/mm\^3 (\>= 100 GI/L) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Hemoglobin \>= 8 g/dL (\>= 80 g/L) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Alanine aminotransferase (ALT), aspartate aminotransferase (AST) =\< 3 x upper limit of normal (ULN) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Total bilirubin =\< 1.5 x upper limit of normal (ULN) (subjects with Gilbert's disease =\< 2 x ULN and direct bilirubin within normal limits are permitted) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Serum albumin \>= 2.8 g/dl (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Serum creatinine =\< 2.0 x ULN or calculated creatinine clearance \>= 30 mL/min (\>= 0.5 mL/sec) using the Cockcroft-Gault equation (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Urine protein/creatinine ratio (UPCR) =\< 1 mg/mg (=\< 113.2 mg/mmol) (subjects may not have received blood product transfusion or G-CSF within 14 days prior to screening)

• Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1

• Male or non-pregnant and non-breast feeding female:

‣ Women of child-bearing potential (WOCBP) must agree to use highly effective contraception without interruption from initiation of therapy and continue until 4 months (120 days) after last dose of study therapy. WOCBP must have a negative serum pregnancy test (beta-human chorionic gonadotropin \[hCG\]) result at screening and agree to ongoing pregnancy testing during the study, and at the end of study treatment. A highly effective method of contraception is defined as one that results in a low failure rate (that is, \< 1% per year), when used consistently and correctly, such as implants, injectables, combined oral contraceptives, some intrauterine contraceptive devices, sexual abstinence, or a vasectomized partner

⁃ Male subjects must practice abstinence or agree to use a condom during sexual contact with a pregnant female or a female of childbearing potential while participating in the study

• Life expectancy of \> 3 months, as determined by the investigator

• Ability to understand and sign informed consent

• Willingness and ability to comply with scheduled visits, laboratory tests, and other study procedures