Patient description: A Pap smear in a 54-year-old woman revealed abnormal cervical squamous intraepithelial/glandular lesion. She tested positive for HPV 16. She is sexually active with her husband and has 4 children. She is menopausal and uses no contraception. She smokes and drinks alcohol frequently. She is otherwise healthy. She was offered conization.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Endometrial Cancer Carcinosarcoma Patients must be enrolled or agree to consent to the companion genomic profiling study MSKCC IRB# 12-245 Part A. Results are not required prior to initiating treatment on protocol, unless patients do not have other test results by IHC or FISH confirming HER2 overexpression Patients must have recurrent or persistent HER2 overexpressing endometrial cancer or endometrial carcinosarcoma. HER2 overexpression is defined as 3+ by IHC or 2+ with gene amplification by FISH (HER2/CEP17 ratio ≥ 2) or HER2 amplified (fold change ≥ 2) on MSK Histologic documentation of diagnosis of endometrial carcinoma or carcinosarcoma is required Age ≥ 18 years Patients must have had at least one but no more than two prior chemotherapeutic regimens for management of endometrial carcinoma (including neo-adjuvant and/or adjuvant chemotherapy). Initial treatment may chemotherapy, chemotherapy and radiation therapy, and/or consolidation/maintenance therapy. Chemotherapy administered in conjunction with primary radiation as a radio-sensitizer WILL be counted as a systemic chemotherapy regimen. Prior hormonal therapy will not count as a prior regimen. Prior treatment with trastuzumab is allowed Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 LVEF ≥ 50% on baseline screening ECHO Resolution of adverse effects of recent surgery, radiotherapy, or chemotherapy to Grade ≤ 1 prior to first study treatment (with the exception of alopecia or clinically insignificant laboratory values) Patients must have measurable disease. Measurable disease is defined by (version 1.1). Measurable disease is defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded). Each non-nodal lesion must be 10 mm when measured by CT, MRI or caliper measurement by clinical exam; or 20 mm when measured by chest x-ray. Lymph nodes must be ≥ 15 mm in short axis when measured by CT or MRI No active infection requiring antibiotics (with the exception of uncomplicated urinary tract infection)  Women who are pregnant or lactating or women of childbearing potential (WCBP) not protected by highly-effective contraceptive methods > Grade 1 peripheral neuropathy History of hemorrhagic or ischemic stroke within the prior six months History of NYHA Class II-IV heart failure, no serious arrhythmia History of MI or unstable angina within 6 months of study initiation Patients with a lifetime cumulative dose of anthracycline >300 mg/m2 or who have received anthracycline treatment within 90 days of the expected first dose of ZW25 are not eligible for treatment Prior hypersensitivity to monoclonal antibodies Active hepatitis B or hepatitis C infection. Patients with previously resolved hepatitis B infection are eligible. Presence of positive test results for hepatitis B infection who have resolved the infection (defined by positive for HB surface antibody (anti-HBs) and polymerase chain reaction (PCR) assay is negative for HBV DNA are eligible. Patients positive for HCV antibody are eligible only if testing for HCV RNA is negative Known HIV infection Current severe, uncontrolled systemic disease (e.g., clinically significant cardiovascular, pulmonary, or metabolic disease)