Learning More About the Risks of Expectant Management
More men than ever are being diagnosed with prostate cancer when it is very early — with minimal, low-grade cancer. Some of these men choose to have the cancer removed; at Hopkins, about a fourth of men who undergo radical prostatectomy have this kind of “insignificant” disease. But some of these men, with their doctor’s guidance, decide on a course of “expectant management” — active surveillance, with PSA and needle biopsies, until there is evidence
that the cancer has progressed.
“A concern for these men is whether their cancer will become worse in grade over time,” says Jonathan I. Epstein, M.D., the Rose-Lee and Keith Reinhard Professor of Urologic Pathology. This movement from a nice, harmless, low-grade cancer toward a higher-grade cancer that needs to be treated is called “dedifferentiation.” Differentiated cells have well-defined, or differentiated, walls, and grow slowly. The worst cancer cells are poorly differentiated, and seem to melt with other cells into blobs.
What can these men expect? Until recently, no one knew. In a recent study, led by Epstein and published in the Journal of Urology, pathologists monitored grade changes over time in 241 men with cancer considered “good” enough to follow expectantly — too small to be felt, with an initial Gleason score of 6 or lower. For the majority of men, the cancer did not progress right away. “Our results suggest that if dedifferentiation does occur, the risk is low in the short-term,” Epstein says.
But sometimes it did progress, and this seemed to happen fairly quickly. Epstein suspects that these men probably had more advanced cancer cells in the prostate all along — but they had so few of them, they weren’t detected by needle biopsy. About 19 percent (45 men) showed a significant change in grade to a Gleason score of 7 or higher (41 men), and 4 men showed a Gleason score of 8. “About half of the men who moved to a higher grade did so within 24 months of diagnosis,” says Epstein.
Other men showed an increase in Gleason grade after three years, and “this may represent true dedifferentiation,” says Epstein. Many of the men in this study had multiple biopsies over three years of follow-up, and showed no change. “This suggests extremely low volumes of tumor in these patients, and very slow-growing tumors,” says Epstein. “These results should be reassuring to patients suspected of harboring small-volume, low-grade cancer,
and they further support the concept of active surveillance as a reasonable alternative
to immediate surgery or radiation.”