diff --git a/pydicom/pixel_data_handlers/pillow_handler.py b/pydicom/pixel_data_handlers/pillow_handler.py
index ff781025d..adcab9c80 100644
--- a/pydicom/pixel_data_handlers/pillow_handler.py
+++ b/pydicom/pixel_data_handlers/pillow_handler.py
@@ -129,7 +129,10 @@ def _decompress_single_frame(
                 image.tile[0][2],
                 (color_mode, ''),
             )]
-            image.mode = color_mode
+            if hasattr(image, "_mode"):
+                image._mode = color_mode
+            else:
+                image.mode = color_mode
             image.rawmode = color_mode
     return image