Unfortunately, when radiotherapy is discussed for prostate cancer, it is all lumped together in one general category “radiotherapy.” However, there are drastic differences in the radiotherapy given, and below are the key features that should be asked about and/or described to truly understand the treatment given.
- The Dose
- Hormonal modulation
- RT without hormone therapy is inadequate therapy
- Minimum 2 years ADT needs to be given – only cut short if the patient can’t tolerate it or refuses, but should be the standard of care
- Bolla study was criticized for not having an ADT alone arm – but Widmark et al SPCG-7 study answered that question. RT+ADT was better than ADT alone.
- ADT is a radiosensitizer – mechanism was only really understood 2 years ago
- The Length of administration
- He believes treatment of primary PCa will be shortened eventually to 3-5 days!
- As such, there is increased interest in maximizing the dosage of radiation to the primary tumor – while reducing morbidity
- However, he also pointed out that the most common site of tumor recurrence following RT to the prostate is where the original tumor was – not in another region of the prostate. That has led to increased efforts to increase radiation doses to the primary lesion and reduce radiation to the rest of the prostate (a “boost” to the dominant lesion)
This is achieved in many different ways:
- HDR and LDR brachy is one method
- FLAME – “focal lesion ablative microboost” is another that is being evaluated
Yet, all these modalities are grouped together when talking about RT for prostate cancer. Therefore, he wants to remind the audience that when talking about RT, always know the radiation dose, the schedule and the specifics of the modality – so you can compare results appropriately. Radiotherapy for the prostate is rapidly changing!
Presented by: Gert De Meerleer, MD, Ph.D, Universitair Ziekenhuis Leuven, Department of Radiation Oncology, Ghent, Belgium
Written by: Thenappan Chandrasekar, MD. Clinical Instructor, Thomas Jefferson University, Twitter: @tchandra_uromd, @TjuUrology, at the 16th Meeting of the European Section of Oncological Urology, #ESOU19, January 18-20, 2019, Prague, Czech Republic