Sequential Measurement of Bone Mineral Density Identifies Ongoing Recovery of Detrimental Bone Mass in Very Long Term Adult Survivors of Childhood Cancer

Aim of this study was to investigate status and longitudinal evolvement of BMD in long-term adult survivors.

A single-center cohort of 410 adult long-term survivors (171 females) was included in this retrospective study. Age at diagnosis was 6.6 years (0.0–16.8 yrs), and at follow up 24.5 years (18.0–49.3 yrs). Median follow-up time was 15.2 years (5.1–39.8 yrs).

BMD of the lumbar spine (BMD_LS) and total body (BMD_TB) were measured. Results were compared with healthy age matched controls.

Overall BMD_TB and BMD_LS were low in long-term survivors (median standard deviation score (SDS) −0.60, P < 0.001 and median SDS −0.40, P < 0.001 respectively). In ALL survivors both BMD_TB (median SDS −0.65, P < 0.001) and BMD_LS (median SDS −0.48, P < 0.001) were low. Backwards elimination of the multivariate linear regression analysis showed that both cranial irradiated and/or total body irradiated survivors were at significant risk for low BMD_TB. BM(A)D_LS was not different between survivors and controls and no risk factors were identified for low BM(A)D_LS. In general, a slight but significant improvement of BMD_TB and BMD_LS was found in our sequential measurement. This BMD improvement was not found for ALL survivors alone.

Our study shows low BMD in childhood cancer survivors treated with cranial or total body irradiation. However, sequential DXA analysis shows ongoing recovery of bone mass, which suggests a potential for reaching peak bone mass later in life.

No relevant conflicts of interest to declare.