diff --git a/rules-tests/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector/Fixture/skip_memoize_item_by_key.php.inc b/rules-tests/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector/Fixture/skip_memoize_item_by_key.php.inc
new file mode 100644
index 00000000000..c3e1b473b25
--- /dev/null
+++ b/rules-tests/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector/Fixture/skip_memoize_item_by_key.php.inc
@@ -0,0 +1,17 @@
+<?php
+
+namespace Rector\Tests\Php70\Rector\StmtsAwareInterface\IfIssetToCoalescingRector\Fixture;
+
+class SkipMemoizeItemByKey
+{
+    private $items = [];
+
+    public function resolve($key)
+    {
+        if (isset($this->items[$key])) {
+            return $this->items[$key];
+        }
+
+        return $this->items[$key] = 'fallback value';
+    }
+}
diff --git a/rules/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector.php b/rules/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector.php
index 0a1e76a39ee..a2ad3211474 100644
--- a/rules/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector.php
+++ b/rules/Php70/Rector/StmtsAwareInterface/IfIssetToCoalescingRector.php
@@ -6,6 +6,7 @@
 
 use PhpParser\Node;
 use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\Assign;
 use PhpParser\Node\Expr\BinaryOp\Coalesce;
 use PhpParser\Node\Expr\Isset_;
 use PhpParser\Node\Expr\Ternary;
@@ -113,6 +114,11 @@ public function refactor(Node $node): ?Node
                 continue;
             }
 
+            if ($stmt->expr instanceof Assign &&
+                $this->nodeComparator->areNodesEqual($ifOnlyStmt->expr, $stmt->expr->var)) {
+                continue;
+            }
+
             unset($node->stmts[$key - 1]);
 
             if ($stmt->expr instanceof Ternary) {