Periampullary Adenomyoma: Clinicopathological Characteristics of Cases from a Single Center

Abstract

Background
Adenomyoma is a benign tumor-like lesion, which is rarely found in the extrahepatic biliary tree, ampulla of Vater, and duodenum. Clinical findings vary by lesion location, and diagnosis often follows surgical intervention.

Materials and Methods
The study included seven patients diagnosed with periampullary adenomyoma whose data were analyzed by sex, age, laboratory data, clinical and radiological features, preoperative diagnosis, surgical techniques, pathological and immunohistochemistry findings, and outcomes.

Results
The patients were men aged 31-74 years. Abdominal pain was the most frequent clinical symptom. In most cases, the pre-operative clinical impression was malignancy. Almost every case underwent Whipple resection. Submucosal nodules were the predominant macroscopic feature, and microscopically, all cases showed hyperplastic glandular lobules encircling a larger duct. In most cases, there was no atypia or mitotic figures. The most common immunohistochemical pattern was positive immunoreactivity for CK7, CDX2, MUC1, MUC6, and MUC5AC and negative immunoreactivity for CK20 and MUC2.

Conclusion
Periampullary adenomyomas are manifested in different forms. Although preoperative endoscopy, ERCP, frozen section, and tissue biopsy of the mass may not be definitive, they can suggest adenomyoma when used together and help avoid unnecessary pancreaticoduodenectomy, which burdens both the surgeon and the patient.