Factors influencing lymph node metastasis in patients with ampullary adenocarcinoma

[Treatment of Ampullary Adenocarcinoma]

The ampulla of Vater is a small projection formed by the confluence of the main pancreatic duct and common bile duct in the second part of the duodenum. Primary ampullary adenocarcinoma is a rare malignancy, accounting for only 0.2% of gastrointestinal cancers and approximately 7% of all periampullary cancers. Jaundice from a biliary obstruction is the most common symptom of ampullary adenocarcinoma. In the early stages, radical pancreatoduodenectomy is the standard surgical approach. On the other hand, no randomized controlled trial has provided evidence to guide physicians on the choice of adjuvant/palliative chemotherapy because of the rarity of the disease and the paucity of related research. This paper reports the biology, histology, current therapeutic strategies, and potential future therapies of ampullary adenocarcinoma.

Artificial Intelligence to Predict Lymph Node Metastasis at CT in Pancreatic Ductal Adenocarcinoma

Background Although deep learning has brought revolutionary changes in health care, reliance on manually selected cross-sectional images and segmentation remain methodological barriers. Purpose To develop and validate an automated preoperative artificial intelligence (AI) algorithm for tumor and lymph node (LN) segmentation with CT imaging for prediction of LN metastasis in patients with pancreatic ductal adenocarcinoma (PDAC). Materials and Methods In this retrospective study, patients with surgically resected, pathologically confirmed PDAC underwent multidetector CT from January 2015 to April 2020. Three models were developed, including an AI model, a clinical model, and a radiomics model. CT-determined LN metastasis was diagnosed by radiologists. Multivariable logistic regression analysis was conducted to develop the clinical and radiomics models. The performance of the models was determined on the basis of their discrimination and clinical utility. Kaplan-Meier curves, the log-rank test, or Cox regression were used for survival analysis. Results Overall, 734 patients (mean age, 62 years ± 9 [SD]; 453 men) were evaluated. All patients were split into training (n = 545) and validation (n = 189) sets. Patients who had LN metastasis (LN-positive group) accounted for 340 of 734 (46%) patients. In the training set, the AI model showed the highest performance (area under the receiver operating characteristic curve [AUC], 0.91) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.58, 0.76, and 0.71, respectively. In the validation set, the AI model showed the highest performance (AUC, 0.92) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.65, 0.77, and 0.68, respectively (P < .001). AI model-predicted positive LN metastasis was associated with worse survival (hazard ratio, 1.46; 95% CI: 1.13, 1.89; P = .004). Conclusion An artificial intelligence model outperformed radiologists and clinical and radiomics models for prediction of lymph node metastasis at CT in patients with pancreatic ductal adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Chu and Fishman in this issue.

Development and Validation of a New Lymph Node Ratio-Based Staging System for Ampullary Carcinoma After Curative Pancreaticoduodenectomy

Background

Lymph node metastasis (LNM) is closely associated with the prognosis of ampullary carcinoma (AC). The purpose of this study is to explore the relationship between lymph node ratio (LNR) and the prognosis of patients with AC after curative pancreaticoduodenectomy and to establish a new LNR-based staging system.

Methods

AC patients in the Cancer Hospital, Chinese Academy of Medical Sciences, between 1998 and 2020 were retrospectively reviewed as the training cohort; and AC patients in the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2018 were obtained as the validation cohort. Within the training group, Kaplan–Meier survival analyses and Cox proportional hazards regression were conducted to assess the prognostic value of LNR and establish a new LNR-based staging system. Then, the new staging system was compared with the 8th American Joint Committee on Cancer (AJCC) TNM staging system in both the training and validation cohorts.

Results

A total of 264 patients in the training cohort and 199 patients in the validation cohort were enrolled. Significant overall survival (OS) difference was observed between LNR-low stage and LNR-high stage in both training (p = 0.001) and validation cohorts (p < 0.001). Then a new LNR-based staging system was developed. Under the new system, the number of patients in the training cohort and validation cohort of stage I, stage II, and stage III was 30 (11%) vs. 18 (9%), 190 (72%) vs. 96 (48%), and 44 (17%) vs. 85 (43%), respectively. The new staging system classified patients with respect to survival better than did the 8th AJCC TNM staging system.

Conclusions

The new LNR-based staging system had better discriminability for predicting survival in AC patients after curative pancreaticoduodenectomy. More data are needed for further validation.

Ampullary Carcinoma: An Overview of a Rare Entity and Discussion of Current and Future Therapeutic Challenges

Ampullary carcinomas (ACs) represent a rare entity, accounting for approximately 0.2% of all gastrointestinal solid tumors and 20% of all periampullary cancers (PACs). Unfortunately, few data are available regarding the optimal therapeutic strategy for ACs due to their rarity, and physicians frequently encounter significant difficulties in the management of these malignancies. In this review, we will provide an overview of current evidence on AC, especially focusing on biological features, histological characteristics, and available data guiding present and future therapeutic strategies for these rare, and still barely known, tumors.

Ampullary carcinoma of the duodenum: current clinical issues and genomic overview

Ampullary carcinomas of the duodenum are uncommon. Moreover, the diversity in the clinical outcomes of these patients makes it difficult to interpret previous studies and clinical trial results. The difficulty in proper staging of ampullary carcinomas, especially with regard to the T category of the tumor in the TNM system, reflects the anatomic complexity and non-uniform histopathologic subtypes. One major reason for this difficulty in interpretation is that the tumors may arise from any of the three epithelia (duodenal, biliary, or pancreatic) that converge at this location. Generally, ampullary carcinomas are classified into intestinal and pancreaticobiliary types based on morphology and immunohistochemical features. While many studies have described their specific characteristics and clinical impact, the prognostic value of these subtypes is controversial. In recent years, whole-exome sequencing analyses have advanced our understanding of the genomic overview of ampullary carcinoma. Gene mutations serve as prognostic and predictive biomarkers for this disease. Therefore, basic knowledge of the genomic profile of ampullary carcinomas is required for surgeons to understand how best to apply precision medicine as well as surgery and adjuvant therapies. This review provides an overview of the current basic and clinical issues of ampullary carcinoma.

Prognostic value of the lymph node metastasis in patients with ampulla of Vater cancer after surgical resection

Backgrounds/Aims

Patients with Ampulla of Vater cancer have a better prognosis than those with other periampullary cancers. This study aimed to determine the prognostic impact of lymph node metastasis on survival in patients with ampulla of Vater cancer after surgical resection.

Methods

From 1991 to 2016, we retrospectively reviewed data on 104 patients with ampulla of Vater cancer who had received pancreaticoduodenectomy. Clinicopathologic factors such as lymph node ratio (LNR) and number of metastatic lymph nodes that influence survival were statistically analyzed.

Results

5-year survival rate after resection was 57.8%. Mean number of retrieved and metastatic lymph nodes was 13 and 0.95, respectively. In patients with lymph node metastasis, the median number of metastatic lymph nodes and was 1, and the mean LNR was 0.18. LNR >0.2 was a significant prognostic factor for overall survival. Patients with 0 or 1 metastatic lymph nodes had better survival than those with ≥2 metastatic lymph nodes. Univariate analysis revealed that histologic differentiation of tumor, lymph node metastasis, and T stage were significant prognostic factors for overall survival. Multivariate analysis revealed that tumor differentiation and number of metastatic lymph nodes were independent prognostic factors for survival.

Conclusions

Pancreaticoduodenectomy is an appropriate surgical procedure with acceptable long-term survival for ampulla of Vater cancer. Patients with LNR >0.2 and ≥2 positive lymph node metastasis had a poor survival. Tumor differentiation and ≥2 metastatic lymph nodes were independent significant prognostic factors for overall survival. Curative resection with lymph node dissection might control lymph node spread and enhance survival outcomes.