Prostate cancer nomenclature at diagnosis can affect treatment decisions

When researchers asked study participants who were cancer-free to consider their reaction to a hypothetical diagnosis of low-grade prostate cancer with either a Gleason score (GS) of 6 out of 10 or an International Society of Urological Pathology (ISUP) GG of 1 out of 5, use of the latter terminology was associated with lower anxiety as well as a greater preference for active surveillance rather than unnecessary immediate treatment according to a new study published in Cancer (published online June 3, 2021. doi:10.1002/cncr.33621).

The ISUP introduced its prostate cancer GG system in 2014 as a replacement for the widely used, decades-old GS system. Nonetheless, some pathologists, urologists, and other clinicians still refer to a prostate cancer’s GS in pathology reports, in clinical notes, and in discussions with patients.

The original 1966 GS system ranked the microscopic appearance of the prostate on a scale of 2 to 10. However, by the year 2000, criteria for assigning a GS had changed so much that experts recommended never using a GS of 2, 3, or 4 in pathology reports of core biopsies (Am J Surg Pathol. 2000;24:477-478. doi:10.1097/00000478-200004000-00001), and even a GS of 5 was very uncommon for these specimens. This resulted in a situation in which a GS of 6 was often assumed to be on a scale of 1 to 10 (and, therefore, higher than “average”) when, in fact, 6 was essentially the lowest GS ever used for prostate biopsies.

It is widely agreed by clinicians that telling patients that they have a GS of 6 to describe their low-grade prostate cancer can be confusing and a barrier for patients to agree to active surveillance, says senior study author Shilajit D. Kundu, MD, chief of urologic oncology in the Department of Urology and associate professor of urology at Northwestern University Feinberg School of Medicine in Chicago, Illinois, but the term is still fairly common. “This issue is important because how you present a new cancer diagnosis is critical for the patient’s initial mindset,” says Dr. Kundu. “Even though the diagnosis is the same, because the [GS] number 6 [out of 10] is higher [than GG 1 out of 5], the diagnosis seems worse and can cloud a patient’s decisions, leading to unnecessary treatment out of fear.”

Another part of the study investigated the effect of removing the word cancer entirely for a malignant neoplasm diagnosis and instead opting for the term IDLE. “So, the purpose of this study was to assess how these 3 terms (Gleason, GG, and IDLE) impact patients and their clinicians,” adds Dr. Kundu.