DESTINY-PANTUMOUR04

This study is a multicenter, hybrid, observational study of approximately 100 prospectively enrolled patients with HER2-positive (IHC 3+) solid tumors in the US initiated on trastuzumab deruxtecan (T-DXd) as per FDA label in routine clinical practice and enrolled at the point of starting treatment with T-DXd. Patients with locally advanced, unresectable, or metastatic HER2-positive (IHC 3+) solid tumors who have received prior systemic treatment for metastatic or advanced disease and have no satisfactory alternative treatment options will be eligible for inclusion. Patients with breast, colorectal, non-small cell lung cancer (NSCLC), gastric/gastroesophageal junction (GEJ) cancers, and haematological malignancies are not eligible for this study. Approximately 30 sites will be selected including community oncology practices, hospital systems and academic medical centers (AMCs), with a focus on enrolling a patient population representative of real-world care with the majority of patients from community settings. The primary objective of the study is to assess real world response rate and real world duration of response, and the secondary objective is to assess real world time to treatment discontinuation and real world time to next treatment.