===== Definition of Targeted Radiotherapy =====

**Targeted radiotherapy** is a form of cancer treatment in which radioactive substances are delivered **specifically to tumor cells** or tumor-associated structures, minimizing exposure to healthy tissues.

Key aspects include:
  * **Specific Targeting**: Radioactive molecules are attached to ligands (such as antibodies, peptides, or small molecules) that recognize and bind to tumor-specific markers (e.g., PSMA in prostate cancer or glioblastoma neovasculature).
  * **Localized Radiation**: After binding to the target, the radioactive component emits radiation (commonly beta or alpha particles) that destroys cancer cells in the immediate vicinity.
  * **Reduced Side Effects**: Compared to conventional external beam radiotherapy, targeted radiotherapy offers greater precision and reduces collateral damage to normal tissues.

Examples:
  * **¹⁷⁷Lu-PSMA-617 therapy** for prostate cancer and glioblastoma.
  * **¹⁷⁷Lu-DOTATATE therapy** for neuroendocrine tumors.