Is Grade Group 1 (Gleason score 3 + 3 = 6) adenocarcinoma of the prostate really cancer?
Jonathan I. Epstein
Abstract
PURPOSE OF REVIEW: Whether Grade Group 1 (GG1) prostate cancer is really cancer remains controversial. RECENT FINDINGS: Favoring renaming GG1 with a noncancerous diagnosis are: fear of the term cancer, which will lead to overtreatment of GG1; and indolence of GG1. Favor designating GG1 as cancer are: morphologically, GG1 may be indistinguishable from GG2 to GG5 and GG1 is invasive (lacks basal cells), can show perineural invasion and extraprostatic extension; molecularly, GG1 has many of the hallmarks of prostate cancer; calling GG1 noncancer would lead to inconsistencies and confusion in reporting; sampling error with GG1 on biopsy can miss higher grade cancer; removing the label of cancer in men with GG1 on biopsy may make it challenging to insure follow-up during active surveillance; the prognosis of treated GG1 may not be the same if GG1 called noncancer and not treated; with Grade Group terminology, GG1 is more intuitive to patients as lowest grade cancer; and patients are increasingly adopting active surveillance, recognizing that not all prostate cancers are the same and GG1 can be followed carefully and safely on active surveillance. SUMMARY: There is strong support for retaining the carcinoma designation for GG1.