Which patients with prostate cancer benefit the most from radiotherapy after radical prostatectomy?

This article looked at the pathological features of prostate cancer to identify those patients who would benefit the most from adjuvant radiotherapy after radical prostatectomy.

One option for patients with prostate cancer is surgery to remove the cancer along with the entire prostate gland and some healthy tissues around it, to make sure that all the cancer is removed. This surgery is called a radical prostatectomy (RP). However, when a pathologist examines the removed tissues, sometimes the outer surface of these tissues may still have cancer present. These are called positive surgical margins. This indicates that some cancer cells may still present in the patient also. In these cases, patients may benefit from additional (adjuvant) treatments such as hormone therapy, radiotherapy or chemotherapy. This study aimed to find the cancer-related features based on which prostate cancer patients would benefit from RP.

This article evaluated 1049 prostate cancer patients treated with RP between 1998 and 2008. All of the participants had positive surgical margins, with or without positive lymph nodes (cancer that has spread to the nearby lymph nodes). All patients also received adjuvant treatments after RP. Analysis of the patients’ cancer features and treatments allowed the authors of the study to identify a group of patients who benefitted the most from adjuvant radiotherapy.

They identified three factors which independently affected a patients survival time: a Gleason score (a grading system for prostate cancer aggressiveness based on how the cancer cells look under a microscope) of 8 or more, positive lymph nodes and a pathologic cancer stage of T3 or T4 (cancer that has spread to the tissues near the prostate gland). Each of these factors was given a score of 1 if present, allowing a patient to obtain a total risk score between 0 and 3.

Patients with a risk score of 0 or 1 did not have significant survival benefit after adjuvant radiotherapy. The 10 year survival rate (the percentage of patients surviving 10 years after treatment) for these patients was 97.6% with adjuvant radiotherapy and 96.6% without radiotherapy. However, patients with a risk score of 2 or more did benefit from adjuvant radiotherapy. They had a 10 year survival rate of 69.6% without radiotherapy, which increased to 79.9% in patients who were treated with radiotherapy after RP.

In summary, adjuvant radiotherapy significantly improved survival for patients with at least two of these cancer features: a Gleason score of 8 or higher, positive lymph nodes and a pathological stage T3 or T4 prostate cancer. Overall, the information provided in this article helps select a specific group of patients who can benefit from radiotherapy and to reduce the number of patients who will have unnecessary radiotherapy. 

This study looked back at patients who have been treated in the past (retrospective study), rather than following patients throughout their treatment and determining their outcomes. Retrospective studies are known to provide weak statistical information. Also, some patients who received radiotherapy also received other adjuvant treatments that might have influenced their survival. 

Talk to your doctor whether radiotherapy is a good option for your situation.