Researchers from the Medical University of Innsbruck in Austria studied the possibility of under-grading in prostate cancer biopsies. The study is entitled “High Risk of Under-Grading and -Staging in Prostate Cancer Patients Eligible for Active Surveillance” and was published in the journal PLOS ONE.

Prostate cancer is a curable cancer that can range from slow-growing tumors (more common) to rapidly progressing aggressive tumors. The diagnosis of prostate cancer can be made through the analysis of blood for prostate-specific antigens (PSA) and is especially important to detect individuals with an aggressive cancer form at an early stage.

Patients with low risk prostate cancer are usually offered active surveillance (AS), where the cancer is monitored closely for any alterations. AS goal is to reduce overtreatment of patients with low risk prostate cancers and therefore, no treatment is provided (radiation, medication or surgery) during this phase. Several studies have been conducted to determine the impact of several biomarkers in disease progression in patients under AS, as many eligible patients have been upgraded due to final histological results.

Researchers assessed the risk of tumor under-grading and under-staging when applying the AS eligibility criteria at the time of biopsy and analyzed potential biomarkers for unfavorable tumor histology. Patients who underwent radical prostatectomy (RPE – removal of the prostate gland) and met the established criteria for AS by the European Association of Urology were evaluated (197 in total). All patients were caucasians and the average age at biopsy was 60.2 years. Patients were grouped according to their preoperative PSA levels as low (≤ 4 ng/mL, 46.2% of patients) or intermediate (> 4–10 ng/mL, 53.8% of patients), PSA density (<0.15 vs ≥ 0.15 ng/mL), and number of positive biopsy cores (1 or 2). The predicting upgrading and final adverse histology of RPE patients were also analyzed.

Researchers found that 41.1% of the patients were under-graded based on biopsy, underlying the risk and consequences of under-grading. In addition, neither the preoperative PSA levels, nor PSA density or number of positive cores were indicative of a worse pathological outcome. The team also found that almost 20% of the patients who were biopsy under-graded experienced a relapse after RPE, indicating that under-grading in patients eligible for AS has led to prostate cancer progression.

The team concluded that several patients that meet the criteria for AS are in fact under-diagnosed and emphasize that adopting the AS regime has to be considered very carefully, especially in young men. Further studies based on the search for viable biomarkers to discriminate the severity of the disease are also of extreme importance.