What is the significance of a Gleason score of 3+3 (Gleason grading system) in prostate cancer diagnosis?

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From the Guidelines

Gleason score 3+3 is considered the lowest grade of prostate cancer, corresponding to Grade Group 1, and is characterized by well-differentiated and typically slow-growing tumors. This score is based on the histopathologic evaluation of prostate tissue, where the two numbers (3+3) represent the two most predominant patterns of cancer cells observed under a microscope [ 1 ]. A pattern of 3 indicates that the cancer cells still form recognizable gland structures and appear somewhat similar to normal prostate tissue. According to the AUA/ASTRO/SUO guideline, patients with Gleason score 3+3 are considered to have low-risk disease, with a very favorable outcome and low probability of adverse pathology at surgery and low rate of metastatic disease when managed with active surveillance [ 1 ].

Some key characteristics of Gleason score 3+3 prostate cancer include:

  • Well-differentiated tumor cells that form recognizable gland structures
  • Typically slow-growing, with a low risk of progression
  • Corresponds to Grade Group 1, the lowest grade of prostate cancer
  • Often has a favorable prognosis, with many men never needing aggressive treatment
  • May be managed with active surveillance, involving regular monitoring with PSA blood tests, digital rectal exams, and possibly repeat biopsies to track any progression [ 1 ].

It's worth noting that the management of Gleason score 3+3 prostate cancer should be individualized, taking into account the patient's overall health, age, and preferences [ 1 ]. However, in general, the slow-growing nature of Gleason 3+3 prostate cancer means that many men with this diagnosis can avoid the potential side effects of surgery or radiation therapy, and instead opt for active surveillance or other conservative management approaches [ 1 ].

From the Research

Definition of Gleason Score 3+3

  • The Gleason score is a system used to grade the aggressiveness of prostate cancer, with higher scores indicating more aggressive cancer 2.
  • A Gleason score of 3+3=6 is considered a low-grade cancer, with a debate ongoing about whether it is a clinically significant disease 2.
  • The score is calculated by adding the grades of the two most prevalent patterns of cancer cell growth in the tumor, with a range of 2-10 3.

Clinical Significance of Gleason Score 3+3

  • Studies have shown that patients with a Gleason score of 3+3=6 have a low risk of adverse outcomes, such as seminal vesicle invasion and nodal disease 4.
  • However, the consequences of treatment for Gleason score 3+3=6 disease can be significant, with few men escaping treatment without some harm 2.
  • The National Comprehensive Cancer Network (NCCN) guidelines consider patients with a biopsy Gleason score of 3+4 or less to be candidates for active surveillance, but the long-term outcomes for these patients are not well understood 4.

Patient Understanding of Gleason Score

  • Patient knowledge of the Gleason scoring system is generally low, even among well-educated and health-literate individuals 5.
  • Patients' understanding of the importance of the Gleason score is moderate, and is positively associated with their knowledge of the system 5.
  • Simplifying the Gleason grading system and improving patient-provider communication may be necessary to maximize shared treatment decision-making 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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