January 1988 to April 1992, 26 patients with advanced head and neck carcinoma underwent head and neck reconstructive surgery with pectoralis major myocutaneous flap (PM-MCF). Over the same period, all cases were submitted to CT to assess the value of this technique in the follow-up. Fourteen patients relapsed (54%). Of them, 5 (36%) were positive on both clinical examination and CT; 8 cases (57%) exhibited evidence of disease on CT only and in 1 patient (7%) CT was negative and the recurrence appeared as a fistula on follow-up exams. CT was of great value in the management of the patients with advanced head and neck carcinoma treated with reconstructive surgery with PM-MCF. However, CT findings must be carefully interpreted because postoperative and postirradiation complications or anatomic alterations may mimic tumor recurrences.