Testing Ado-Trastuzumab Emtansine as a Potential Targeted Treatment in Cancers With HER2 Genetic Changes (MATCH-Subprotocol Q)

Inclusion Criteria:

• Patients must have met applicable eligibility criteria in the Master MATCH Protocolprior to registration to treatment subprotocol

• Patients' tumor sample must have HER2 amplification > 7 based on targeted customAmpliseq panel on the Ion Torrent Personal Genome Machine (PGM)

• Hemoglobin >= 9.0 g/dL (which may be reached by transfusion)

• Patients will be allowed if on anticoagulation (except warfarin and other coumarinderivatives) or on aspirin 81 mg by mouth daily. Additional monitoring while onanticoagulation will be based on institutional guidelines and/or physiciandiscretion. However, patients will not be allowed if on long acting anti-plateletagents such as clopidogrel

• Patients must have an electrocardiogram (ECG) within 4 weeks prior to treatmentassignment and must have no clinically important abnormalities in rhythm, conductionor morphology of resting ECG (e.g. complete left bundle branch block, third degreeheart block)

• Patients must have echocardiography (ECHO) or nuclear study (multigated acquisitionscan [MUGA] or First Pass) within 4 weeks prior to registration to treatment andmust not have a left ventricular ejection fraction (LVEF) < 50% to be eligible

• Women of childbearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, forthe duration of study participation, and for 7 months after completion of study

Exclusion Criteria:

• Patients with a diagnosis of breast cancer or gastric/gastroesophageal junction (GEJ) cancer will be excluded

• Patients must not have known hypersensitivity to ado-trastuzumab emtansine orcompounds of similar chemical or biologic composition

• Patients with current peripheral neuropathy of grade 3 or greater (National CancerInstitute [NCI]-Common Toxicity Criteria [CTC], version 4.0) will be excluded

• Neuropathy assessment and grade assignment will be based on history (location,duration, balance and gait, effect on activity of daily living [ADLs]) andphysical exam

• Patient must not have had any of the prior therapies:

• Food and Drug Administration (FDA) approved:

• Trastuzumab

• Pertuzumab

• Ado-trastuzumab emtansine

• Investigational:

• Margetuximab

• PF-05280014 (Pfizer, Trastuzumab Biosimilar)

• CT-P6 (Celltrion, Trastuzumab Biosimilar)

• ABP-980 (Amgen, Trastuzumab Biosimilar)