Theranostics + Targeted Therapy

What is Theranostics in nuclear medicine?

The term THERANOSTICS is a combination of two words: THERAPY and DIAGNOSTICS.

The meaning of this medical term is that a THERAPY measure is applied only according to a diagnostic scan performed on the same patient that is intended to receive the therapy, leading to what is called now “personalized medicine” or “precision medicine”. The diagnostic scan is usually a molecular imaging scan done with PET-CT or SPECT-CT imaging modality. Using “Theranostics”, the trial and error medicine approach is avoided.

Theranostics play a significant role in the image guided drug delivery treatments. New molecular diagnostic scans find the precise cancer cell molecules to be target, for example, neuroendocrine granules with 18-F-DOPA or peptide hormones receptors such as Somatostatin receptors in Neuroendocrine tumors (NETs) or prostate-specific membrane antigen (PSMA) in prostate cancer.

Since 2010 ISOTOPIA MOLECULAR IMAGING is providing the medical community in Israel with 68-Ga-Dotatate for PET-CT imaging and shortly afterwards with 177-Lu-Dotatate for theranostics in NETs.
Currently there are 3 medical centers in Israel providing 177-Lu-Dotatate therapy, performing 3-4 treatments per week.

Since 2016 ISOTOPIA did the same with another theranostics couple, 68-Ga-PSMA and 177-Ga-PSMA bringing hope for patients with metastatic castration resistant prostate cancer who suffer from progressing disease and exhausted all other conventional therapies.

What is Targeted Therapy?

Since cancer cells may vary from patient to patient and even within the same patient, it is necessary first to determine if all cancer cells exhibit the receptors molecules against which the treatment is designed and to what extent. Therefore, the imaging/diagnostic step is crucial for patient selection and for the prediction of treatment success. This process is what it makes it personalized and precise.

In addition, as opposed to chemotherapy that affects the whole body, using “Targeted Therapy” means that instead of affecting the whole body, the targeted drug will be used to bind only to cancer cells that exhibit the receptors molecules against which the treatment is designed and destroy those cancer cells selectively.
The success of the treatment process is also under monitoring using the same imaging modality applied for the selection process. 

Therefore, when a targeted therapy is given using a radio-labeled drug, radiation will not harm healthy tissue, but only the tumor cells, the therapeutic impact is significant and side effects are minimized.

In nuclear medicine, the use of 177-Lu-Dotatate therapy in NETs and 177-Lu-PSMA in prostate cancer are examples for targeted therapy.