diff --git a/torchvision/csrc/deform_conv2d.h b/torchvision/csrc/deform_conv2d.h
index d802147b660..3f65036a9b1 100644
--- a/torchvision/csrc/deform_conv2d.h
+++ b/torchvision/csrc/deform_conv2d.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API at::Tensor deform_conv2d(
     const at::Tensor& input,
     const at::Tensor& weight,
@@ -23,25 +22,5 @@ VISION_API at::Tensor deform_conv2d(
     int64_t offset_groups,
     bool use_mask);
 
-// C++ Backward
-VISION_API
-std::tuple<at::Tensor, at::Tensor, at::Tensor, at::Tensor, at::Tensor>
-_deform_conv2d_backward(
-    const at::Tensor& grad,
-    const at::Tensor& input,
-    const at::Tensor& weight,
-    const at::Tensor& offset,
-    const at::Tensor& mask,
-    const at::Tensor& bias,
-    int64_t stride_h,
-    int64_t stride_w,
-    int64_t pad_h,
-    int64_t pad_w,
-    int64_t dilation_h,
-    int64_t dilation_w,
-    int64_t groups,
-    int64_t offset_groups,
-    bool use_mask);
-
 } // namespace ops
 } // namespace vision
diff --git a/torchvision/csrc/nms.h b/torchvision/csrc/nms.h
index f7dfafe0454..efe50acc136 100644
--- a/torchvision/csrc/nms.h
+++ b/torchvision/csrc/nms.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API at::Tensor nms(
     const at::Tensor& dets,
     const at::Tensor& scores,
diff --git a/torchvision/csrc/ps_roi_align.h b/torchvision/csrc/ps_roi_align.h
index bd9df43a90e..b04359b70ed 100644
--- a/torchvision/csrc/ps_roi_align.h
+++ b/torchvision/csrc/ps_roi_align.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API std::tuple<at::Tensor, at::Tensor> ps_roi_align(
     const at::Tensor& input,
     const at::Tensor& rois,
@@ -15,19 +14,5 @@ VISION_API std::tuple<at::Tensor, at::Tensor> ps_roi_align(
     int64_t pooled_width,
     int64_t sampling_ratio);
 
-// C++ Backward
-VISION_API at::Tensor _ps_roi_align_backward(
-    const at::Tensor& grad,
-    const at::Tensor& rois,
-    const at::Tensor& channel_mapping,
-    double spatial_scale,
-    int64_t pooled_height,
-    int64_t pooled_width,
-    int64_t sampling_ratio,
-    int64_t batch_size,
-    int64_t channels,
-    int64_t height,
-    int64_t width);
-
 } // namespace ops
 } // namespace vision
diff --git a/torchvision/csrc/ps_roi_pool.h b/torchvision/csrc/ps_roi_pool.h
index 21f3c640e0e..c9ae946a4e2 100644
--- a/torchvision/csrc/ps_roi_pool.h
+++ b/torchvision/csrc/ps_roi_pool.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API std::tuple<at::Tensor, at::Tensor> ps_roi_pool(
     const at::Tensor& input,
     const at::Tensor& rois,
@@ -14,18 +13,5 @@ VISION_API std::tuple<at::Tensor, at::Tensor> ps_roi_pool(
     int64_t pooled_height,
     int64_t pooled_width);
 
-// C++ Backward
-VISION_API at::Tensor _ps_roi_pool_backward(
-    const at::Tensor& grad,
-    const at::Tensor& rois,
-    const at::Tensor& channel_mapping,
-    double spatial_scale,
-    int64_t pooled_height,
-    int64_t pooled_width,
-    int64_t batch_size,
-    int64_t channels,
-    int64_t height,
-    int64_t width);
-
 } // namespace ops
 } // namespace vision
diff --git a/torchvision/csrc/roi_align.h b/torchvision/csrc/roi_align.h
index 9397d0a173e..84c357d9c5f 100644
--- a/torchvision/csrc/roi_align.h
+++ b/torchvision/csrc/roi_align.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API at::Tensor roi_align(
     const at::Tensor& input,
     const at::Tensor& rois,
@@ -16,19 +15,5 @@ VISION_API at::Tensor roi_align(
     int64_t sampling_ratio,
     bool aligned);
 
-// C++ Backward
-VISION_API at::Tensor _roi_align_backward(
-    const at::Tensor& grad,
-    const at::Tensor& rois,
-    double spatial_scale,
-    int64_t pooled_height,
-    int64_t pooled_width,
-    int64_t batch_size,
-    int64_t channels,
-    int64_t height,
-    int64_t width,
-    int64_t sampling_ratio,
-    bool aligned);
-
 } // namespace ops
 } // namespace vision
diff --git a/torchvision/csrc/roi_pool.h b/torchvision/csrc/roi_pool.h
index 92a2670d98c..ceebf201769 100644
--- a/torchvision/csrc/roi_pool.h
+++ b/torchvision/csrc/roi_pool.h
@@ -6,7 +6,6 @@
 namespace vision {
 namespace ops {
 
-// C++ Forward
 VISION_API std::tuple<at::Tensor, at::Tensor> roi_pool(
     const at::Tensor& input,
     const at::Tensor& rois,
@@ -14,18 +13,5 @@ VISION_API std::tuple<at::Tensor, at::Tensor> roi_pool(
     int64_t pooled_height,
     int64_t pooled_width);
 
-// C++ Backward
-VISION_API at::Tensor _roi_pool_backward(
-    const at::Tensor& grad,
-    const at::Tensor& rois,
-    const at::Tensor& argmax,
-    double spatial_scale,
-    int64_t pooled_height,
-    int64_t pooled_width,
-    int64_t batch_size,
-    int64_t channels,
-    int64_t height,
-    int64_t width);
-
 } // namespace ops
 } // namespace vision