MRI-based monitoring feasible for prostate cancer active surveillance

Magnetic resonance imaging (MRI)-based surveillance and monitoring for prostate cancer is a feasible approach and may help avoid unnecessary biopsies, a recent study has found.

“We showed that most patients, particularly those with Gleason 3 + 3 cancer and nonvisible disease at baseline, remained on imaging-based surveillance at five years, whereas the leading cause of active surveillance (AS) discontinuation was combined radiological and pathological progression,” researchers said.

Of the 672 men enrolled at baseline, 84.7 percent remained under AS at 3 years. This retention rate dropped only slightly to 71.8 percent at 5 years. Over more than 3,800 person-years of follow-up, 32.1 percent (n=216) underwent treatment and 24 participants died, though none were related to prostate cancer.

In addition, metastasis developed in eight participants, while 27 progressed to Gleason ≥4 + 3 upon follow-up biopsy.

Event-free and treatment-free survival rates were significantly lower in patients with MRI-visible disease, or in those with secondary Gleason pattern 4 at baseline (log-rank p<0.001). In most cases, treatment for malignancy was preceded by pathological and radiological progression of the disease, though MRI progression alone also emerged as an important factor for treatment initiation.

An important limitation of the present study is its single-centre, retrospective design, the researchers said. Given that there is large inter-centre variability in MRI interpretation, this limits the generalizability of the present findings. Moreover, the current investigation failed to look at the longitudinal trends in patients under AS.

Further studies are therefore needed to more accurately evaluate the natural history of MRI-visible and MRI-invisible prostate cancer, they added.