Yes, it’s possible.
Depending on the way you build your menu, you’d have to call the posts like this (fill in placeholders):
// Call/Query the posts related to the category:
$your_cat_related_cpts = get_posts( array(
'post_type' => 'YOUR_CUSTOM_POST_TYPE'
,'category' => 'YOUR_CATEGORY'
) );
// Append them to your menu:
foreach ( $your_cat_related_cpts as $content )
{
echo $content->post_title;
}