Inclusion Criteria:  Male or female, at least 18-years of age; Provide written informed consent; Chemotherapy naïve subject with histologically or cytologically confirmed malignant disease; or chemotherapy non-naïve subject with histologically proven diagnosis of cancer; Karnofsky index ≥ 50; Be scheduled to receive MEC to be administered on Day 1;  Exclusion Criteria:  Unable to understand or cooperate with study procedure； Received any investigational drug 30 days prior to study entry； Used any drug with anti-emetic efficacy 24 hours prior to treatment and during the study； Enrollment in a previous study with palonosetron； Seizure disorder requiring anticonvulsant medication; Experienced any vomiting, retching, or NCI Common Toxicity Criteria grade 2 or 3 nausea in the 24 hours preceding chemotherapy； Ongoing vomiting from any organic etiology； Experienced nausea (moderate to severe or vomiting following any previous chemotherapy)； Scheduled to receive moderately or highly-emetogenic chemotherapy or radiotherapy during the study； Known contraindication to 5-HT3 antagonist or dexamethasone； Lactating female.