diff --git a/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php b/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
index 05d215f63c..2b3c25889b 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/BaseType.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Form\Extension\Core\Type;
 
+use Symfony\Component\Form\AbstractRendererEngine;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\FormBuilderInterface;
 use Symfony\Component\Form\FormInterface;
@@ -100,7 +101,7 @@ abstract class BaseType extends AbstractType
             // collection form have different types (dynamically), they should
             // be rendered differently.
             // https://github.com/symfony/symfony/issues/5038
-            'cache_key' => $uniqueBlockPrefix.'_'.$form->getConfig()->getType()->getBlockPrefix(),
+            AbstractRendererEngine::CACHE_KEY_VAR => $uniqueBlockPrefix.'_'.$form->getConfig()->getType()->getBlockPrefix(),
         ]);
     }