Register page in admin area

    <td><form action="<?php menu_page_url('edit') ?>" method="post">
            <input type="hidden" id="<?php echo $issue->id?>" name="id" value="1">
            <input type="submit" value="Edit">
        </form>
    </td>

Then, in the function where you add your admin pages:

    add_submenu_page( null, 'edit', 'Edit', $capability, 'edit', 'create_edit');

Also add this function:

function create_edit(){
    include 'edit.php';
}

It would probably be a good thing to have more unique names than these.