Evaluation of intermittent androgen deprivation therapy for locally advanced prostate cancer.

The study compared patient-reported outcomes (PRO) in patients receiving continuous androgen deprivation therapy (CADT) vs intermittent androgen deprivation therapy (IADT) for locally advanced prostate cancer (PCa). The study reported that PROs were significantly improved with IADT.

ADT is a hormonal therapy that reduces androgens (male sex hormones such as testosterone) that help PCa cells to grow. ADT reduces the growth and spread of PCa. ADT is usually recommended continuously (CADT) for the treatment of advanced PCa. However, this continuous administration over a longer period of time often leads to side effects such as hot flashes, decreased sexual function, tiredness, anemia and decreased bone density which can lead to bone fractures. This decreases the quality of life of patients. 

Recently, it has been shown that the intermittent administration of ADT (IADT; patients take breaf breaks during therapy) may have similar effectiveness as CADT with fewer side effects. However, the patient reported outcomes (PROs; how the patients perceive this treatment) of IADT vs CADS are unknown.

The study enrolled 280 patients with locally advanced PCa (cancer has spread beyond the prostate, in the same area). All patients were treated with 6 months of ADT followed by radiation therapy. After this, patients were randomly assigned to receive either CADT for 5 years or IADT for 6 months. In the IADT group, after the 6 months of ADT, patients started again ADT if their prostate-specific antigen (PSA; a protein made by the prostate glad used as a marker for PCa) levels started to rise above 5 ng/ml. Patients were followed up for an average of 8.2 years. Questionnaires were used to evaluate PROs.

After 20 months, the overall scores for quality of life were significantly improved in the IADT group, while they were worse in the CADT group. Patients in the ADT group also had better scores for physical well-being at 38 months and emotional well-being at 20 months compared to those in the CADT group. Functional scores were also better in the IADT group at 14 and 20 months.

The study concluded that patients who underwent IADT had a significantly better quality of life compared to CADT.

This study included Japanese patients, therefore the results may not apply to other populations. Also, data regarding patients' other medical conditions was not available. Other serious medical conditions may impact PROs.