Display list/menu records within 'echo' statement


Hope you can advise with this one. I have a long form in php, a portion of which is only displayed using php and echo depending on user variables previously obtanted from a MYSQL database. This is a snippet of testing code below can anyone advise on how I can get a list/menu created by php echo to display values previously entered during the forms validation process?

$selected = $_POST['list'];
echo $selected;

<form name="form1" method="post" action="<?php $_SERVER["PHP_SELF"]; ?> ">

echo '<select name="list" id="list">
      <option value=';if ($_POST['list'] == "1") echo "SELECTED";'>item1</option>
      <option value="2">item2</option>
      <option value="3">item3</option>
    <input type="submit" name="Submit" value="Submit">

Any advice or pointers greatly appreciated.