The Gleason score is a system used to grade the aggressiveness of prostate cancer. Its lowest classification, Gleason 6, is a subject of significant discussion. The nature of Gleason 6 often causes confusion, as its classification as “cancer” is debated due to its typically indolent behavior. This article clarifies what Gleason 6 signifies and why it remains a subject of ongoing discussion in the medical community.
Understanding the Gleason Score
Pathologists determine the Gleason score by examining prostate tissue samples under a microscope, typically obtained through a biopsy. They assign two grades, from 1 to 5, based on how closely cancer cells resemble normal prostate tissue. A lower grade, like 1, indicates cells look very similar to healthy cells, while a higher grade, such as 5, means cells appear very abnormal.
The two most prevalent grades from the biopsy are added together to produce a total Gleason score, which typically ranges from 6 to 10. For example, a score of 3+3=6 means both primary and secondary patterns are grade 3. A higher total score generally indicates a more aggressive cancer that is more likely to grow and spread quickly.
The Nature of Gleason 6
Gleason 6 is the lowest possible score on the Gleason grading system, often represented as 3+3=6. This score signifies that the cancer cells, while abnormal, still largely resemble normal prostate gland structures. Unlike higher-grade prostate cancers, Gleason 6 is characterized by its slow-growing and non-aggressive behavior. Many experts argue that pure Gleason 6 lesions have little to no capacity to metastasize.
The debate surrounding Gleason 6 centers on whether it should be labeled “cancer” due to its indolent nature. Some medical professionals suggest that calling it cancer can lead to patient anxiety and potentially unnecessary treatments, a concept sometimes referred to as overdiagnosis and overtreatment. Autopsy studies show Gleason 6 is common in aging males, suggesting it may be part of the natural aging process rather than a life-threatening malignancy. The lack of metastatic potential and the fact that men are generally not reported to have died from solely Gleason 6 disease further fuel this discussion.
Managing Gleason 6
The management of Gleason 6 prostate cancer often differs significantly from higher-grade cancers due to its low-risk characteristics. For many patients, active surveillance is the preferred approach. This strategy involves closely monitoring the cancer without immediate definitive treatment, aiming to avoid the side effects associated with surgery or radiation.
Active surveillance typically includes regular prostate-specific antigen (PSA) blood tests, digital rectal exams (DREs), and periodic repeat prostate biopsies to track any changes in the cancer. This allows medical teams to intervene with more aggressive treatments only if there is evidence of progression, such as an increase in the Gleason score or tumor volume. Immediate definitive treatments, like radical prostatectomy or radiation therapy, are often avoided for Gleason 6 unless specific circumstances warrant them, primarily due to potential side effects such as urinary, bowel, and sexual dysfunction, which may outweigh the benefits for such a slow-growing cancer.
Patient Considerations
Receiving a diagnosis of Gleason 6 prostate cancer can understandably cause significant anxiety, even though it is considered a very low-risk form of the disease. Patients often grapple with the psychological burden of a “cancer” label, despite understanding that immediate aggressive treatment may not be necessary. Individuals should engage in shared decision-making with their medical team, openly discussing their concerns and preferences.
Factors such as a patient’s age, overall health, and personal values play a significant role in determining the most suitable management plan. Some individuals may prefer the peace of mind that comes with immediate treatment, while others may opt for active surveillance to avoid potential treatment side effects. Seeking a second opinion from another specialist can also provide additional perspectives and help patients feel more confident in their chosen course of action.