CT analysis of postoperative tumor recurrence patterns in periampullary cancer

Background: We analyzed postoperative tumor recurrence in periampullary cancer on computed tomography (CT). Methods: Forty-six patients with tumor recurrence (16 pancreas head cancers, 19 distal common bile duct cancers, and 11 ampulla of Vater cancers) of 125 patients who underwent surgery for periampullary cancer were enrolled. Recurrence was diagnosed by CT findings plus elevated CA 19-9 (n=28) or biopsy (n=18). Two radiologists retrospectively reviewed 156 contrast-enhanced CT scans, with 7-mm slice thickness, obtained in our institution until the initial diagnosis of tumor recurrence. The modes of recurrence were classified as local recurrence, hepatic metastasis, lymph node metastasis, peritoneal carcinomatosis, or extraabdominal metastasis. We evaluated the time of recurrence, the frequency of each mode of recurrence, and the earliest mode of recurrence. The differences in tumor recurrence for the three types of periampullary cancer were evaluated. Results: Half of the recurrences occurred within 6 months after surgery and 87% occurred within 12 months after surgery. Local recurrences (67%), hepatic metastases (72%), and lymph node metastases (61%) were common modes of tumor recurrence. Pancreas head cancers recurred earlier than the other types of periampullary cancer (p<0.05). Conclusion: Periampullary cancer tends to recur early after surgery, usually as a local recurrence, hepatic metastasis, or lymph node metastasis.