The primary difference lies in the type of clinical information they provide. A **diagnostic biomarker** helps identify, classify, or subclassify a disease. It answers the question "What is it?" For example, the presence of CD20 confirms a lymphoma is of B-cell origin, and specific cytokeratin patterns can distinguish between different types of carcinoma. A **predictive biomarker**, in contrast, provides information about the likely response to a specific therapy. It answers the question "Will this treatment work?" Predictive biomarkers are used to select patients for targeted therapies. Classic examples include: HER2 overexpression in breast/gastric cancer predicting response to trastuzumab (Herceptin), PD-L1 expression in various cancers predicting potential response to immune checkpoint inhibitors, and the presence of mismatch repair deficiency (loss of MLH1/PMS2) predicting response to immunotherapy in colorectal cancer. A single marker can sometimes be both (e.g., HER2 is diagnostic of a subtype and predictive of therapy response).

Break down complex topics into smaller, manageable chunks for easier recall.

Zambia

• Naomi Miselo – 31 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies