Custom field display on php if value

I’m trying to display a custom field, a summary, on pages that include a review box for my posts.

The bit of code that includes the review template if it is checked while making the post looks like this:

<?php 							$result_cmb_is_review = get_post_meta($post->ID, 'cmb_is_review', true);
if ($result_cmb_is_review == 'checked')
{include 'inc/template_review.php';
}
?>

I’d like to add this code for a summary box after the review box in the post with this in it:

<h3><?php _e('Summary'); ?></h3>
<p><?php get_field( "review_summary" ); ?></p>

But I only want the Summary field to show up if the post is checked to be a review. I can’t seem to figure out how to get both the template and the custom field to show up only if the review is checked. Any tips would be wonderful.