In this study, people are followed while they receive their regular cancer treatment with ADC medicines that their doctor chooses. The study does not give the medicines. It only watches how people do during their treatment. People can join before starting their first ADC or before starting their second ADC. The study follows them through each ADC treatment and then continues to check on them for two years after the second ADC. During treatment, people will answer questions about how they feel, the medicines they take, and any side effects. They will also fill out questionnaires about symptoms every other cycle. They will give small blood samples at certain times. If a biopsy is already being done as part of their normal care, extra tissue may be collected for research, but this is optional.