Optimising Hormone Therapy in Localised and Early Disease

Abstract

Prostate cancer (PCa) is being diagnosed at an earlier age, and at an earlier stage of disease. Increasing numbers of relatively young patients (<60 years) with localised and early disease are receiving radical therapy. The addition of hormonal therapy in an adjuvant and/or neoadjuvant setting is widely used in clinical practice. The key issue when dealing with optimising hormone therapy in localised and early disease is to identify the patients who will benefit from this form of treatment, and optimise the timing of initiation as well as duration of the treatment. The current literature was reviewed to address this issue. Traditionally, most patients diagnosed with localised disease receive radical therapy, either radiation therapy or radical prostatectomy. However, many men have indolent PCa and may not require radical therapy. In contrast, patients with aggressive disease benefit from local therapy. As a consequence, the main clinical challenge is the stratification of patients with localised disease into good risk patients and intermediate-to-high risk patients in order to offer the patient a tailored treatment strategy. Patients diagnosed with good risk disease (stage T1c–T2a, Gleason score ≤6, small volume of disease on biopsy and prostate specific antigen (PSA) ≤10 ng/mL) can be closely monitored with periodic biopsies and measurement of the PSA doubling time (DT). Patients diagnosed with an aggressive form of disease (intermediate-to-high risk disease) need immediate curative therapy. Both radical prostatectomy and radiotherapy are currently used in combination with neoadjuvant and/or adjuvant hormonal therapy. Neoadjuvant therapy prior to radical prostatectomy has failed to demonstrate an improvement in PSA progression in numerous randomised trials. However, one trial showed a benefit in high risk patients (PSA >20 ng/mL) after 3 months of neoadjuvant therapy, based on retrospective stratification analysis. Overall, some practitioners recommend neoadjuvant therapy for patients with high risk localised PCa. Adjuvant hormonal therapy after surgery has not, to date, demonstrated an improvement in overall or disease specific survival, but does delay PSA progression. The significance of this remains uncertain. Neoadjuvant hormonal therapy prior to radiation therapy is recommended for patients with intermediate-to-high risk disease. The optimal duration of neoadjuvant hormone therapy is not yet defined. However, a 3 to 6 month course of neoadjuvant therapy prior to radiation is widely utilised. Adjuvant hormonal therapy after radiotherapy is also widely used in patients with intermediate-to-high risk disease. The optimal duration of adjuvant therapy is between 6 months and 3 years. For patients with biochemical failure, androgen deprivation therapy is appropriate for those whose clinical and pathologic parameters indicate that local recurrence is unlikely. For such patients who are at high risk (Gleason ≥8, or PSA DT <1 year), androgen deprivation should be implemented when the PSA is between 5 and 10 ng/mL. For lower risk patients, or those who have secondary failure after initial attempt at salvage radiation, there is no evidence that early androgen deprivation enhances survival or time to androgen independent progression. These patients should be monitored and treated upon clinical progression or rapid biochemical progression.