diff --git a/pandora/annotation/models.py b/pandora/annotation/models.py
index 24d2871e..51b08770 100644
--- a/pandora/annotation/models.py
+++ b/pandora/annotation/models.py
@@ -209,19 +209,15 @@ class Annotation(models.Model):
     def _get_entity_json(self, user=None, entity_cache=None):
         """When serializing many annotations pointing to the same entity, it is expensive to
         repeatedly look up and serialize the same entity.
-
-        TODO: if Entity were a (nullable) foreign key of Annotation, we could just:
-
-            prefetch_related('entity', 'entity__user', 'entity__documents')
-
-        before serializing the annotations, which would make self.entity.json(user=user) cheap and
-        all this unnecessary.
         """
+        from entity.models import Entity
+
         if entity_cache is not None and self.value in entity_cache:
             return entity_cache[self.value]
 
-        entity = self.get_entity()
-        entity_json = entity.json(user=user)
+        id = ox.fromAZ(self.value)
+        entity = Entity.objects.filter(id=id).only('name').get()
+        entity_json = entity.json(keys=['id', 'name'])
         value = entity.annotation_value()
 
         if entity_cache is not None: