Comparison between the location and the histomorphological/immunohistochemical characteristics of noninvasive neoplasms of the ampulla of Vater

Indicative value of pathological classification of duodenal papillary adenomas in clinical diagnosis and treatment

OBJECTIVES

The relationship between the pathological classification and recurrence of duodenal papillary adenomas (DPAs) has not been elucidated. We studied the clinicopathological characteristics of DPAs with different pathological types and conducted long-term follow-up to explore its prognosis and identify methods for appropriate clinical management of DPAs.

METHODS

In total, 95 DPA cases confirmed by postoperative pathology were enrolled, of which 58 underwent endoscopic papillectomy (EP) and 37 underwent pancreatoduodenectomy (PD). The cases were classified into three anatomical and two histomorphological types according to the histopathology and location of endoscopic features. We analyzed the clinicopathological characteristics of DPAs with different pathological types and investigated the factors associated with recurrence in the EP subgroup.

RESULTS

Although EP was associated with fewer adverse events, the complete resection rate was significantly lower (72.4% vs. 100.0%, p < 0.001) and the recurrence rate significantly higher than with PD (16.3% vs. 0.0%, p < 0.001). Among eight EP cases with recurrence, six had intra-DPA (75%). A positive resection margin (HR 23.67, 95% CI 6.42-87.27; p < 0.001) and MUC2-negative status (HR 3.47, 95% CI 1.16-10.40; p = 0.026) were independent risk factors for recurrence after EP.

CONCLUSION

We identified different pathological types within DPAs, which presented varying clinicopathological features. The majority of peri-DPAs and mixed-DPAs were of the intestinal type histologically and EP is the primary recommendation. However, intra-DPA was mainly of the pancreaticobiliary type, which tends to get positive resection margins; thus, surgical resection is more suitable.

Clinical practice guidelines for endoscopic papillectomy

The Japan Gastroenterological Endoscopy Society has developed the "Clinical Practice Guidelines for Endoscopic Papillectomy (EP)" as a fundamental guideline using scientific approach. EP is a recently spreading therapeutic modality for ampullary tumors ranked as high risk endoscopic technique. Because of the paucity of high level of evidence, strength of recommendations had to be determined by a consensus among specialists. These guidelines, shed light on the following five issues: Indications, Preoperative/intraoperative preparations and techniques, Early adverse events, Therapeutic outcomes and remnants/recurrences, and Follow-up and late adverse events, to guide current clinical practice on EP.

Endoscopic papillectomy: The limits of the indication, technique and results

In the majority of cases, duodenal papillary tumors are adenomas or adenocarcinomas, but the endoscopy biopsy shows low accuracy to make the correct differentiation. Endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography are important tools for the diagnosis, staging and management of ampullary lesions. Although the endoscopic papillectomy (EP) represent higher risk endoscopic interventions, it has successfully replaced surgical treatment for benign or malignant papillary tumors. The authors review the epidemiology and discuss the current evidence for the use of endoscopic procedures for resection, the selection of the patient and the preventive maneuvers that can minimize the probability of persistent or recurrent lesions and to avoid complications after the procedure. The accurate staging of ampullary tumors is important for selecting patients to EP or surgical treatment. Compared to surgery, EP is associated with lower morbidity and mortality, and seems to be a preferable modality of treatment for small benign ampullary tumors with no intraductal extension. The EP procedure, when performed by an experienced endoscopist, leads to successful eradication in up to 85% of patients with ampullary adenomas. EP is a safe and effective therapy and should be established as the first-line therapy for ampullary adenomas.