PHPMailer: Conditional Statement on Email Template

Not sure if I am doing this correctly or if it is even possible. Basically, I just need to change the background color of a table <td> depending on the value of variable $cascadeType.

In an attempt to make this happen, I tried using $_SESSIONS to store the form input as seen on the following code:

<?php
// starting the session
 session_start();
 if (isset($_POST['Submit'])) { 
 $_SESSION['cascadeType'] = $_POST['cascadeType'];
 } 
?>

Then access the session within the email template (emailtemplate.php) using the code:

<?php 
 // starting the session
 session_start();
?>

Then, within the email template (emailtemplate.php), used the conditional statement below.

<tr>
    <?php if ($_SESSION['cascadeType'] = "Information") : ?>
    <td style="text-align:center; color:#FFF; background-color:#093; margin:10px; padding:10px 5px;" width="20%">
        <h4 style="font-weight:bold;">%cascadeType%</h4>
    </td>
    <?php elseif ($_SESSION['cascadeType'] = "Update") : ?>
    <td style="text-align:center; color:#FFF; background-color:#09F; margin:10px; padding:10px 5px;" width="20%">
        <h4 style="font-weight:bold;">%cascadeType%</h4>
    </td>
    <?php elseif ($_SESSION['cascadeType'] = "Reminder") : ?>
    <td style="text-align:center; color:#FFF; background-color:#F00; margin:10px; padding:10px 5px;" width="20%">
        <h4 style="font-weight:bold;">%cascadeType%</h4>
    </td>
    <?php else : ?>
    <td style="text-align:center; color:#FFF; background-color:#6C3; margin:10px; padding:10px 5px;" width="20%">
        <h4 style="font-weight:bold;">%cascadeType%</h4>
    </td>
    <?php endif ; ?>
<td style="color:#337AB7; text-align:right; padding-right: 20px;" width="80%">
<h3 style="margin-bottom:2px;">TARGET AUDIENCE</h3>
<p style="margin-top:2px;">%targetAudience%</p>
</td>

The email output just displays all table <td> and apparently does not work. Please advise on what is the best way to approach the situation if conditional statements will really not work within an email template