18 June 2024

Hormone Therapy, also known as Androgen Deprivation Therapy (or ADT), is a vital therapy that underpins management of prostate cancer, particularly for those with locally advanced or high risk prostate cancers undergoing radiotherapy and advanced or metastatic prostate cancer.

Previous blogs have focused on hormone therapy and its side effects and the ways to manage these. This blog will map out the stages at which different types of hormone therapy may be used.

Hormone therapy before, during and after radiotherapy

Clinical trials of hormone therapies have demonstrated the benefits of having hormone therapy before, during and in some cases after radiotherapy. The biological effects are thought to be:

  • A reduction of up to 20-50% in prostate size
  • Improvement in urinary symptoms- reduced urinary bother, improved flow rate and reduced residual urine volume
  • A reduction in prostate cancer volumes
  • A reduced ability of prostate cancer cells to repair DNA damage which increases prostate cancer cells sensitivity to radiation therapy

These effects have been showed to improve long term outcomes:

  • reducing the chances of future PSA rises
  • fewer distant metastases
  • reduction in deaths from prostate cancer

This may mean men having radiotherapy for a localised Gleason 7 cancer may benefit from 4-6 months of hormone therapy and those with higher grade or risk cancer may be offered periods of hormone therapy up to two to three years.

There may be benefit is some men with a PSA rise after initial surgery receiving hormone therapy alongside radiotherapy. The evidence for this is evolving and the length of hormone therapy recommended may depend on your Gleason score, PSA level and whether there was cancer detected at the edge or outside the prostate when prostate was removed.

For men commencing hormone therapy there is additional support available through the PCEssentials Clinical Trial. Researchers from the University of Southern Queensland and PCFA are conducting a study seeking to understand how best to improve the quality of support available for men on hormone therapy.

Hormone therapy in advanced prostate cancers

Some men develop advanced or metastatic cancer which recurs after initial and salvage treatments. Some men are initially diagnosed with cancer which has already spread beyond the prostate. Both these types of cancer will likely receive hormone therapy.

Men may progress through a range of stages of where the access to PBS funded medications to treat the disease progression may be indicated and available.

Metastatic Hormone Sensitive Prostate Cancer(mHSPC)

Men with advanced cancer may be initially categorised with described at metastatic hormone sensitive prostate cancer (mHSPC). The local is cancer spots (metastases) and the amount (volume) often determine the treatment path. Men may be recommended a combination of ADT injections, chemotherapy and other tablet forms of hormone therapy, called an Androgen Signalling pathway Inhibitor (ARSI). These include Enzalutamide (Xtandi), Darolutamide (Nubeqa), Apalutamide (Erlyand) and Abiraterone (Zytiga or Yonsa).

Non-Metastatic castrate resistance Prostate Cancer (nmCRPC)

Some men who have been taking hormone therapy alone they may experience consecutive PSA rises.  Sometimes though there will be no evidence of metastatic disease on CT, Bone scans, or MRI. This is called nmCRPC. If three consecutive rises in PSA indicate that the PSA has doubled in a period of less than ten months then people who show no evidence of metastatic disease on conventional imaging may benefit from starting either PBS subsidised Darolutamide (Nubeqa), Apalutamide (Erlyand) or Enzalutamide (Xtandi) in combination with their hormone therapy injection.

Metastatic Castrate Resistant Prostate Cancer (mCRPC)

For some men though there may be evidence of metastatic disease both on scans and with three consecutive PSA rises after initial hormone therapy. This is termed mCRPC. Men who have not previously been prescribed or received a PBS subsided ARSI such as Nubeqa, Zytiga, Yonsa, Erlyand or Xtandi would be eligible to commence one of these in combination with their regular hormone therapy injection.  

While access to these new therapies exist across many indications and stages of the disease men are only eligible to receive a subsidy for an ARSI once in a lifetime. As yet clinical trials have not demonstrated a lasting benefit in using these hormone therapies in a sequence or more than once.

There may be other therapies and clinical trials that men may benefit from.  For those unsure about their options or with questions about treatments available, call PCFA Telenursing Service on 1800 220099 or email your questions to telenurse@pcfa.org.au.

 

Choi, H., Chung, H., Park, J. Y., Lee, J. G., & Bae, J. H. (2016). The Influence of Androgen Deprivation Therapy on Prostate Size and Voiding Symptoms in Prostate Cancer Patients in Korea. International neurourology journal, 20(4), 342–348. https://doi.org/10.5213/inj.1632628.314