This chapter presents a series of case studies with multiple choice questions and answers on Endocrine malignancies. It commences with a discourse on best course of management for a 48-year-old female patient with MEN 2A and metastatic medullary thyroid cancer (MTC), and ends with best step in management of a 72-year-old male with anaplastic thyroid cancer. The chapter also discusses on first step in management of a 37-year-old woman having a fine needle aspiration of both a thyroid mass and lung nodule, the primary cause of morbidity and mortality related to parathyroid carcinoma, and the most common genetic mutation found in papillary thyroid cancer (PTC). .