Radioisotopes for therapy
Some radioisotopes are also used in cancer therapy and are placed directly into the tumor - bound to carrier materials or as implants. They emit their radiation there and only have a local effect. One example is Lutetium-177 (Lu-177), which is produced in the FRM II from Ytterbium (Yb-176) by neutron irradiation and is used to treat so-called endocrine tumors (i.e. tumors in the stomach, intestines, pancreas and lungs).
Other radioisotopes produced at the FRM II are Holmium-166 and Terbium-161, which are mainly used for tumor therapy and occasionally also for imaging.
Lutetium-177 for prostate cancer therapy
For some years, Lu-177 has been used in the treatment of neuroendocrine tumours and / or metastases, such as those that occur in the pancreas. Lu-177 is in this case coupled to a protein molecule, a so-called “ferry”, and thus moves directly into the tumour. Lu-177 is a beta emitter (an electron or a positron is emitted) with the very low range of about two millimeters, which means that healthy tissue remains virtually undamaged.
At the FRM II, Lu-177 is produced from the irradiation of Ytterbium-176 (Yb-176) through a very short-lived nuclide Yb-177, which quickly decays to Lu-177. This process guarantees pure Lu-177 (free of Lu-176) which can then be used without a carrier. This means less radioactive waste for clinics and the preparation can be used for a longer time since, even after 7-10 days, it still contains a sufficient amount of therapeutically active Lu-177.
This technically very complex method was developed by Radiochemistry Munich RCM, which is also a scientific institute based at the TUM, and is utilized commercially today by the ITM Isotope Technologies Munich SE on the site of the FRM II.
The video depicts the complex production of Lu-177:
