Resources · Glossary
Glossary.
Plain-language definitions of every medical term used on lutetium-therapy. Bookmark this page — you'll reference it more than you think.
Medically reviewedUpdated 16 May 2026
- Beta particle
- A type of radiation given off when Lu-177 decays. Travels only about 2 mm, which is what makes it useful for targeting cancer cells without harming nearby healthy tissue.
- CDSCO
- Central Drugs Standard Control Organization — the Indian equivalent of the US FDA. Approves drugs for use in India.
- Chromogranin A (CgA)
- A blood marker often elevated in neuroendocrine tumors. Used to track response to Lu-177 DOTATATE therapy.
- DOTATATE
- A small synthetic peptide that mimics the natural hormone somatostatin. The 'targeting molecule' part of Lu-177 DOTATATE therapy.
- Ga-68 DOTATATE PET
- An imaging scan that uses a Gallium-68 version of DOTATATE to find neuroendocrine tumors. Done before Lu-177 DOTATATE therapy to confirm the cancer has the target.
- Half-life
- How long it takes for half of a radioactive material to decay. Lu-177's half-life is 6.7 days, meaning most of it is gone within 6 weeks of an infusion.
- Lu-177 / Lutetium-177
- The radioactive metal isotope used in Lutetium therapy. Gives off short-range beta radiation that damages cancer cell DNA.
- Lu-177 DOTATATE therapy
- Brand name for Lu-177 DOTATATE, FDA-approved 2018 for neuroendocrine tumors.
- mCRPC
- Metastatic castration-resistant prostate cancer — prostate cancer that has spread (metastasized) and is no longer responding to hormone therapy (castration-resistant). The setting where Lu-177 PSMA therapy is approved.
- Median
- The middle value when all results are lined up. Half of patients do better, half do worse. Often quoted for trial outcomes.
- Metastatic
- Cancer that has spread from its original site to other parts of the body.
- NET / Neuroendocrine tumor
- A type of cancer that arises from hormone-producing cells, often slow-growing. Found in the gut, pancreas, lung, and elsewhere.
- NETTER-1
- Landmark 2017 phase 3 trial that established Lu-177 DOTATATE therapy as standard therapy for midgut NETs.
- NETTER-2
- 2024 phase 3 trial supporting Lu-177 DOTATATE therapy as first-line therapy for higher-grade NETs.
- Lu-177 PSMA therapy
- Brand name for Lu-177 PSMA-617 (vipivotide tetraxetan), FDA-approved 2022 for advanced prostate cancer.
- Progression-free survival (PFS)
- The time from treatment start until cancer worsens (progresses) or the patient dies. A key trial outcome.
- PSA
- Prostate-specific antigen — a blood marker that often correlates with prostate cancer activity. Used to track response to Lu-177 PSMA therapy.
- PSMA
- Prostate-Specific Membrane Antigen — a protein heavily expressed on prostate cancer cells. The target for Lu-177 PSMA therapy.
- PSMA PET
- An imaging scan that uses a PSMA-targeting tracer to find prostate cancer cells. Done before Lu-177 PSMA therapy to confirm the cancer has the target.
- Radionuclide therapy
- Cancer treatment that uses a radioactive substance to kill cancer cells. Lutetium therapy is one type.
- rPFS
- Radiographic progression-free survival — PFS specifically measured by imaging scans rather than just blood markers.
- Somatostatin receptor (SSTR)
- A protein on the surface of many neuroendocrine tumor cells. The target for Lu-177 DOTATATE therapy.
- SPECT
- Single Photon Emission Computed Tomography — a type of scan sometimes done after Lu-177 therapy to visualize where the medicine went.
- Theranostics
- A field combining therapy and diagnostics — using the same targeting molecule to first find cancer (diagnostic scan) and then treat it (therapeutic dose).
- VISION trial
- Landmark 2021 phase 3 trial that won FDA approval for Lu-177 PSMA therapy in advanced prostate cancer.
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