Bone scintigraphy is widely considered as an important technique able to investigate various pathological conditions of the skeletal system. Many unexpected extraosseous uptakes have been reported in literature. We present here three cases of unexpected 99mTc-oxidronate (HDP) myocardial extraosseous uptakes in patients undergoing bone scan for staging purposes. In particular, we present the first reported case ofa myocardial uptake in a patient with IgM-related amyloidosis. Subsequently, we perform a review of the existing literature about extraosseous uptakes.