“…Most studies were from China [27][28][29][30][31][33][34][35][36][37], while only 1 study came from Korea [32]. There were six prospective studies [27,30,33,[35][36][37] and 5 retrospective studies [28,29,31,32,34]. Six studies recruited consecutive patients [27,29,30,34,36,37], while inconsecutive enrollments were found in 5 studies [28,[31][32][33]35].…”