Adjuvant therapy for true ampullary cancer: a systematic review

[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.

Ampullary Cancer: Histological Subtypes, Markers, and Clinical Behaviour-State of the Art and Perspectives

There are different cancers in the peri-ampullary region, including pancreatic ductal adenocarcinoma (PDAC), duodenum cancers (DCs), and ampullary adenocarcinoma (AAC). Here, significant morphological-molecular characterizations should be necessary for the distinction of primary tumours and classifications of their subtypes of cancers. The sub classification of AACs might include up to five different variants, according to different points of view, concerning the prevalence of the two more-cellular components found in the ampulla. In particular, regarding the AACs, the most important subtypes are represented by the intestinal (INT) and the pancreato-biliary (PB) ones. The subtyping of AACs is essential for diagnosis, and their identifications have been impacting clinical management responses to treatments and overall survival (os) after surgery. Pb is associated with a worse clinical outcome. Otherwise, the criteria, through which are possible to attribute its subtype classification, are not well established. A triage of immune markers represented by CK7, CK20, and CDX-2 seem to represent the best compromise in order to split the cohort of AAC patients in the INT and PB groups. The test of choice for the sub-classification of AACs is represented by the immuno-histochemical approach, in which its molecular classification acquires its diagnostic, predictive, and prognostic value for both the INT and PB patients.

Role of adjuvant chemotherapy on recurrence and survival in patients with resected ampulla of Vater carcinoma

BACKGROUND

Owing to rarity of disease and lack of prospective studies, data supporting the role of adjuvant chemotherapy in ampulla of Vater (AoV) carcinoma is limited.

AIM

To evaluate whether adjuvant chemotherapy cases for AoV carcinoma had better disease-free survival (DFS) rates than cases of observation following curative surgery.

METHODS

We retrospectively analyzed the association between adjuvant chemotherapy and DFS and overall survival (OS) in patients with stage IB-III AoV carcinoma who underwent curative surgical resection. Fluorouracil-based adjuvant chemotherapy was administered after surgery at the discretion of the physician. Adjusted multivariate regression models were used to evaluate the association between adjuvant chemotherapy and survival outcomes.

RESULTS

Of the total 104 patients who underwent curative surgery, 52 received adjuvant chemotherapy. Multivariate analysis revealed that higher histologic grade [hazard ratio (HR) = 2.24, P = 0.046], advanced tumor stage (HR = 1.85, P = 0.030), and vascular invasion (HR = 2.14, P = 0.010) were associated with shorter DFS. Adjuvant chemotherapy improved DFS compared to the observation group (HR = 0.50, P = 0.015) and tended to be associated with a longer OS, although the difference was not statistically significant (HR = 0.58, P = 0.098).

CONCLUSION

Among patients with resected AoV carcinoma, the adjuvant chemotherapy group was not associated with a significant survival benefit compared to the observation group. However, on multivariate analysis adjusting for prognostic factors, adjuvant chemotherapy following surgery was an independent prognostic factor for DFS in patients with resected AoV carcinoma. Further studies are needed to investigate the effectiveness of adjuvant chemotherapy according to histologic phenotype.

The Optimal Cutoff Value of Tumor Markers for Prognosis Prediction in Ampullary Cancer

BACKGROUND

Carbohydrate antigen 19-9 (CA 19-9) is a representative tumor marker used for the diagnosis of pancreatic and biliary tract cancers. There are few published research results that can be applied to actual clinical practice for ampullary cancer (AC) alone. This study aimed to demonstrate the relationship between the prognosis of AC and the level of CA 19-9, and to determine the optimal thresholds.

METHODS

Patients who underwent curative resection (pancreaticoduodenectomy (PD) or pylorus preserving pancreaticoduodenectomy (PPPD)) for AC at the Seoul National University Hospital between January 2000 and December 2017 were enrolled. To determine the optimal cutoff values that could clearly stratify the survival outcome, the conditional inference tree (C-tree) method was used. After obtaining the optimal cutoff values, they were compared to the upper normal clinical limit of 36 U/mL for CA 19-9. Results In total, 385 patients were enrolled in this study. The median value of the tumor marker CA 19-9 was 18.6 U/mL. Using the C-tree method, 46 U/mL was determined to be the optimal cutoff value for CA 19-9. Histological differentiation, N stage, and adjuvant chemotherapy were significant predictors. CA 19-9 36 U/mL had marginal significance as a prognostic factor. In contrast, the new cutoff value, CA 19-9 46 U/mL, was found to be a statistically significant prognostic factor (HR: 1.37, p = 0.048).

CONCLUSIONS

The new cutoff value of CA 19-9 46 U/mL may be used for evaluating the prognosis of AC. Therefore, it may be an effective indicator for determining treatment strategies such as surgical treatments and adjuvant chemotherapy.

Multimodal data analysis reveals that pancreatobiliary-type ampullary adenocarcinoma resembles pancreatic adenocarcinoma and differs from cholangiocarcinoma

BACKGROUND

Ampullary adenocarcinoma (AAC) arises from the ampulla of Vater where the pancreatic duct and bile duct join and empty into the duodenum. It can be classified into intestinal and pancreatobiliary types based on histopathology or immunohistochemistry. However, there are no biomarkers for further classification of pancreatobiliary-type AAC which has important implications for its treatment. We aimed to identify the tumor origin of pancreatobiliary-type AAC by systematically analyzing whole-slide images (WSIs), survival data, and genome sequencing data collected from multiple centers.

METHODS

This study involved three experiments. First, we extracted quantitative and highly interpretable features from the tumor region in WSIs and constructed a histologic classifier to differentiate between pancreatic adenocarcinoma (PAC) and cholangiocarcinoma. The histologic classifier was then applied to patients with pancreatobiliary-type AAC to infer the tumor origin. Secondly, we compared the overall survival of patients with pancreatobiliary-type AAC stratified by the adjuvant chemotherapy regimens designed for PAC or cholangiocarcinoma. Finally, we compared the mutation landscape of pancreatobiliary-type AAC with those of PAC and cholangiocarcinoma.

RESULTS

The histologic classifier accurately classified PAC and cholangiocarcinoma in both the internal and external validation sets (AUC > 0.99). All pancreatobiliary-type AACs (n = 45) were classified as PAC. The patients with pancreatobiliary-type AAC receiving regimens designed for PAC showed more favorable overall survival than those receiving regimens designed for cholangiocarcinoma in a multivariable Cox regression (hazard ratio = 7.24, 95% confidence interval: 1.28-40.78, P = 0.025). The results of mutation analysis showed that the mutation landscape of AAC was very similar to that of PAC but distinct from that of cholangiocarcinoma.

CONCLUSIONS

This multi-center study provides compelling evidence that pancreatobiliary-type AAC resembles PAC instead of cholangiocarcinoma in different aspects, which can guide the treatment selection and clinical trials planning for pancreatobiliary-type AAC.

Survival after curative pancreaticoduodenectomy for ampullary adenocarcinoma in a South American population: A retrospective cohort study

BACKGROUND

Ampullary adenocarcinoma (AAC) is a rare neoplasm that accounts for only 0.2% of all gastrointestinal cancers. Its incidence rate is lower than 6 cases per million people. Different prognostic factors have been described for AAC and are associated with a wide range of survival rates. However, these studies have been exclusively conducted in patients originating from Asian, European, and North American countries.

AIM

To evaluate the histopathologic predictors of overall survival (OS) in South American patients with AAC treated with curative pancreaticoduodenectomy (PD).

METHODS

We analyzed retrospective data from 83 AAC patients who underwent curative (R0) PD at the National Cancer Institute of Peru between January 2010 and October 2020 to identify histopathologic predictors of OS.

RESULTS

Sixty-nine percent of patients had developed intestinal-type AAC (69%), 23% had pancreatobiliary-type AAC, and 8% had other subtypes. Forty-one percent of patients were classified as Stage I, according to the AJCC 8th Edition. Recurrence occurred primarily in the liver (n = 8), peritoneum (n = 4), and lung (n = 4). Statistical analyses indicated that T3 tumour stage [hazard ratio (HR) of 6.4, 95% confidence interval (CI) of 2.5-16.3, P < 0.001], lymph node metastasis (HR: 4.5, 95%CI: 1.8-11.3, P = 0.001), and pancreatobiliary type (HR: 2.7, 95%CI: 1.2-6.2, P = 0.025) were independent predictors of OS.

CONCLUSION

Extended tumour stage (T3), pancreatobiliary type, and positive lymph node metastasis represent independent predictors of a lower OS rate in South American AAC patients who underwent curative PD.

Treatment Approach to Adenocarcinoma of the Ampulla of Vater

OPINION STATEMENT

ACs are rare tumors, and thus, there is a lack of prospective trials supporting treatment decisions. Moreover, although anatomically uniform, ACs comprise of biologically distinct entities, depending on what cell type they arise from. This makes the interpretation of limited data even more challenging. Overall, the clinical outcomes of patients with AC are better than those with pancreatic cancer. However, recurrence rates remain high after curative resection. Despite the absence of definitive evidence, we believe that these high recurrence rates are a rational justification for consideration of adjuvant therapy in resected disease, and therapy selection should take tumor biology, stage, resection margins, as well as patient comorbidities and performance status into account. Largely extrapolating from pancreas cancer, we recommend consideration of adjuvant chemotherapy with 6 months of dose-modified FOLFIRINOX in fit patients with pancreatobiliary subtype tumors. Alternative regimens include gemcitabine in combination with capecitabine. If chemoradiotherapy is being added, 6 weeks of radiotherapy in conjunction with 5-FU or capecitabine can be considered. For intestinal subtypes, we recommend 3-6 months of adjuvant FOLFOX. Future studies are needed to evaluate the role of contemporary, multi-agent chemotherapy and chemoradiotherapy in patients with resected and advanced ampullary adenocarcinoma. However, the logistics of performing large randomized trials in patients with a rare cancer is challenging, and the data collection, even in a carefully designed study, would likely take many years. As such, relying on data from basket trials and retrospective analysis will likely serve as guidance for treatment decisions in the near future. Treatment of metastatic disease should employ regimens that are typically used to treat pancreas cancer for tumors of pancreatobiliary subtype and 5-FU-based regimens for intestinal subtypes. Studies specific for patients with advanced AC are much needed. Molecular testing using next-generation sequencing and testing for microsatellite instability (MSI) should be performed on all tumors. We now have disease agnostic options based on these results. Pembrolizumab is approved for MSI-H tumors and tumors with high tumor mutational burden regardless of the primary site. Larotrectinib is approved for tumors with NTRK fusions. At a time when numerous therapeutic agents are in development, for example, those targeting specific K-RAS alterations or NRG fusions, identifying molecular aberrations can significantly impact patient outcomes as well as provide further insights into the biology of disease. In addition, based on recent data suggesting a significant prevalence of germline alterations in patients with ampullary tumors, referral to genetics counselors and germline testing is warranted in a significant proportion of patients with AC.

A population-based study on incidence, treatment, and survival in ampullary cancer in the Netherlands

INTRODUCTION

Ampullary cancer is rare and as a result epidemiological data are scarce. The aim of this population-based study was to determine the trends in incidence, treatment and overall survival (OS) in patients with ampullary adenocarcinoma in the Netherlands between 1989 and 2016.

METHODS

Patients diagnosed with ampullary adenocarcinoma were identified from the Netherlands Cancer Registry. Incidence rates were age-adjusted to the European standard population. Trends in treatment and OS were studied over (7 years) period of diagnosis, using Kaplan-Meier and Cox regression analyses for OS and stratified by the presence of metastatic disease.

RESULTS

In total, 3840 patients with ampullary adenocarcinoma were diagnosed of whom, 55.0% were male and 87.1% had non-metastatic disease. The incidence increased from 0.59 per 100,000 in 1989-1995 to 0.68 per 100,000in 2010-2016. In non-metastatic disease, the resection rate increased from 49.5% in 1989-1995 to 63.9% in 2010-2016 (p < 0.001). The rate of adjuvant therapy increased from 3.1% to 7.9%. In non-metastatic disease, five-year OS (95% CI) increased from 19.8% (16.9-22.8) in 1989-1995 to 29.1% (26.0-31.2) in 2010-2016 (logrank p < 0.001). In patients with metastatic disease, median OS did not significantly improve (from 4.4 months (3.6-5.0) to 5.9 months (4.7-7.1); logrank p = 0.06). Cancer treatment was an independent prognostic factor for OS among all patients.

CONCLUSION

Both incidence and OS of ampullary cancer increased from 1989 to 2016 which is most likely related to the observed increased resection rates and use of adjuvant therapy.

Tissue microarray-chip featuring computerized immunophenotypical characterization more accurately subtypes ampullary adenocarcinoma than routine histology

BACKGROUND

Ampullary adenocarcinomas (AACs) are heterogeneous tumors currently classified into three important sub-classes (SC): Intestinal (INT), Pancreato-Biliary (PB) and Mixed-Type (MT). The different subgroups have similar clinical presentation and are treated by pancreatoduodenectomy with curative intent. However, they respond differently to chemotherapy and have different prognostic outcomes. The SC are often difficult to identify with conventional histology alone. The clinical outcome of all three remains unclear, particularly for MT.

AIM

To identify two main subtypes of AACs, using an immunohistochemical (IHC) score based on CDX2, CK7 and CK20.

METHODS

Tissue samples from 21 patients who had undergone resection of AAC were classified by HE histology and IHC expression of CDX2, CK7 and CK 20. An IHC score was obtained for each marker by counting the number of positive cells (0 = no stained cells; 1 < 25%; 2 < 50% and 3 > 50%) and their intensity (1 = weak; 2 = moderate and 3 = strong). A global score (GS) was then obtained by summation of the IHC scores of each marker. The MT tumors were grouped either with the INT or PB group based on the predominant immuno-molecular phenotype, obtaining only two AACs subtypes. The overall survival in INT and PB patients was obtained by Kaplan-Meier methods.

RESULTS

Histological parameters defined the AACs subtypes as follows: 15% INT, 45% PB and 40% MT. Using IHC expression and the GS, 75% and 25% of MT samples were assigned to either the INT or the PB group. The mean value of the GS was 9.5 (range 4-16). All INT samples had a GS above the average, distinct from the PB samples which had a GS score significantly below the average (P = 0.0011). The INT samples were identified by high expression of CDX2 and CK20, whereas PB samples exhibited high expression of CK7 and no expression of CK20 (P = 0.0008). The INT group had a statistically significant higher overall survival than in the PB group (85.7 mo vs 20.3 mo, HR: 8.39; 95%CI: 1.38 to 18.90; P = 0.0152).

CONCLUSION

The combination of histopathological and molecular criteria enables the classification of AACs into two clinically relevant histo-molecular phenotypes, which appear to represent distinct disorders with potentially significant changes to the current therapeutic strategies.

The prognostic significance of inflammation-based scores in patients with ampullary carcinoma after pancreaticoduodenectomy

Background

Growing evidence indicates that the systemic inflammatory response plays an important role in cancer development and progression. Several inflammatory markers have been reported to be associated with clinical outcomes in patients with various types of cancer. This study was designed to evaluate the prognostic value of inflammatory indexes in patients with ampullary cancer (AC) who underwent pancreaticoduodenectomy (PD).

Methods

We retrospectively reviewed the data of 358 patients with AC who underwent PD between 2009 and 2018. R software was used to compare the area under the time-dependent receiver operating characteristic (ROC) curves (AUROCs) of the inflammation-based indexes, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), modified Glasgow Prognostic Score (mGPS), prognostic nutritional index (PNI) and prognostic index (PI), in terms of their predictive value for survival. The survival differences of these indexes were compared by the Kaplan-Meier method and univariate and multivariate analyses were performed to determine the prognostic factors of disease-free survival (DFS) and overall survival (OS).

Results

The estimated 1-, 2-, and 3-year OS and DFS rates were 83.9, 65.8, and 55.2% and 58.0, 42.8, and 37.8%, respectively, for the entire cohort. The survival differences were significant in terms of OS and DFS when patients were stratified by these inflammation-based indexes. The comparisons of the AUROCs of these inflammation-based indexes illustrated that NLR and PI displayed the highest prognostic value, compared to the other indexes. When NLR and PI were combined, NLR-PI showed even higher AUROC values and was identified as a significant prognostic factor for OS and DFS.

Conclusion

Specific inflammatory indexes, such as NLR, PLR and dNLR, were found to be able to predict the OS or DFS of patients. As a novel inflammatory index, the level of NLR-PI, which can be regarded as a more useful prognostic index, exhibited strong predictive power for predicting the prognosis of patients with AC after the PD procedure.