Ampullary region carcinomas: definition and site specific classification with delineation of four clinicopathologically and prognostically distinct subsets in an analysis of 249 cases. Am J Surg Pathol. 2012;36:1592-1608. [PMID: 23026934 DOI: 10.1097/pas.0b013e31826399d8]

Comparison of clinical characteristics and prognostic factors in two site-specific categories of ampullary cancer

BACKGROUND

Ampullary cancer is a relatively rare malignant tumor in the digestive system. Its incidence has increased in recent years. As for now, its biological characteristics have not been fully clarified. Recent studies have primarily focused on the histological classification and genetic changes, but there are fewer investigations into the differences among site-specific subgroups. The clinicopathological characteristics of ampullary cancer occurring in different positions have not been elucidated. Furthermore, the role of adjuvant therapy in the treatment of patients with ampullary cancer remains controversial.

AIM

To study the clinicopathological features of the two site-specific subgroups of ampullary cancer and explore the factors affecting prognosis.

METHODS

A total of 356 patients who met the inclusion and exclusion criteria were enrolled. Patients were divided into ampulla of Vater cancer (AVC) and duodenal papilla cancer (DPC) based on the gross and microscopic findings. Baseline data, admission examination results, and perioperative outcomes were collected and analyzed. The Kaplan-Meier curve was used for survival analysis. Univariate and multivariate analysis was performed to explore the independent risk factors affecting the overall survival (OS) of both groups.

RESULTS

The preoperative total bilirubin level in patients with AVC was significantly higher than those with DPC (P = 0.04). The OS for patients with DPC was 58.90 ± 38.74 months, significantly longer than 44.31 ± 35.90 months for patients with AVC (P < 0.01). The independent risk factors affecting the OS of AVC included: Preoperative albumin level (P = 0.009), total bilirubin level (P = 0.017), and number of positive lymph nodes (P = 0.005). For DPC, risk factors included: Age (P = 0.004), tumor size (P = 0.023), number of positive lymph nodes (P = 0.010) and adjuvant treatment (P = 0.020). Adjuvant therapy significantly improved the OS rate of patients with DPC, but not for those with AVC.

CONCLUSION

Patients with AVC had a shorter OS compared to those with DPC. The prognosis factors and the role of adjuvant therapy of two groups were different.

Prognostic significance of necrosis in ampullary carcinomas

BACKGROUND/AIMS

Necrosis is an important pathological feature that reflects high malignancy potential in tumors such as hepatocellular carcinoma and renal cell carcinoma. We aimed to elucidate the prognostic impact of necrosis in ampullary carcinomas.

MATERIALS AND METHODS

We reviewed 101 consecutive cases of ampullary carcinoma for tumor necrosis, types of necrosis, macroscopic and microscopic histopathological subtypes, lymphatic-vascular-perineural invasions, and other histopathological parameters.

RESULTS

Tumor necrosis was present in 19 (18.8%) cases and was identified as an independent poor prognostic indicator in multivariate survival analysis (p = 0.029).

CONCLUSION

The presence of necrosis in ampullary carcinomas is directly related to vascular and perineural invasion and is a poor prognostic indicator independent of tumor stage. Including the presence of necrosis in the pathology reports of ampullary carcinomas will facilitate risk stratification.

The Five Periampullary Cancers, not Just Different Siblings but Different Families: An International Multicenter Cohort Study

BACKGROUND

Cancer arising in the periampullary region can be anatomically classified in pancreatic ductal adenocarcinoma (PDAC), distal cholangiocarcinoma (dCCA), duodenal adenocarcinoma (DAC), and ampullary carcinoma. Based on histopathology, ampullary carcinoma is currently subdivided in intestinal (AmpIT), pancreatobiliary (AmpPB), and mixed subtypes. Despite close anatomical resemblance, it is unclear how ampullary subtypes relate to the remaining periampullary cancers in tumor characteristics and behavior.

METHODS

This international cohort study included patients after curative intent resection for periampullary cancer retrieved from 44 centers (from Europe, United States, Asia, Australia, and Canada) between 2010 and 2021. Preoperative CA19-9, pathology outcomes and 8-year overall survival were compared between DAC, AmpIT, AmpPB, dCCA, and PDAC.

RESULTS

Overall, 3809 patients were analyzed, including 348 DAC, 774 AmpIT, 848 AmpPB, 1,036 dCCA, and 803 PDAC. The highest 8-year overall survival was found in patients with AmpIT and DAC (49.8% and 47.9%), followed by AmpPB (34.9%, P < 0.001), dCCA (26.4%, P  =  0.020), and finally PDAC (12.9%, P < 0.001). A better survival was correlated with lower CA19-9 levels but not with tumor size, as DAC lesions showed the largest size.

CONCLUSIONS

Despite close anatomic relations of the five periampullary cancers, this study revealed differences in preoperative blood markers, pathology, and long-term survival. More tumor characteristics are shared between DAC and AmpIT and between AmpPB and dCCA than between the two ampullary subtypes. Instead of using collective definitions for "periampullary cancers" or anatomical classification, this study emphasizes the importance of individual evaluation of each histopathological subtype with the ampullary subtypes as individual entities in future studies.

Intra-ampullary Papillary Tubular Neoplasm (IAPN): Clinicopathologic Analysis of 72 Cases Highlights the Distinctive Characteristics of a Poorly Recognized Entity

The guidelines recently recognized the intra-ampullary papillary tubular neoplasm (IAPN) as a distinct tumor entity. However, the data on IAPN and its distinction from other ampullary tumors remain limited. A detailed clinicopathologic analysis of 72 previously unpublished IAPNs was performed. The patients were: male/female=1.8; mean age=67 years (range: 42 to 86 y); mean size=2.3 cm. Gross-microscopic correlation was crucial. From the duodenal perspective, the ampulla was typically raised symmetrically, with a patulous orifice, and was otherwise covered by stretched normal duodenal mucosa. However, in 6 cases, the protrusion of the intra-ampullary tumor to the duodenal surface gave the impression of an "ampullary-duodenal tumor," with the accurate diagnosis of IAPN established only by microscopic correlation illustrating the abrupt ending of the lesion at the edge of the ampulla. Microscopically, the preinvasive component often revealed mixed phenotypes (44.4% predominantly nonintestinal). The invasion was common (94%), typically small (mean=1.2 cm), primarily pancreatobiliary-type (75%), and showed aggressive features (lymphovascular invasion in 66%, perineural invasion in 41%, high budding in 30%). In 6 cases, the preinvasive component was pure intestinal, but the invasive component was pancreatobiliary. LN metastasis was identified in 42% (32% in those with ≤1 cm invasion). The prognosis was significantly better than ampullary-ductal carcinomas (median: 69 vs. 41 months; 3-year: 68% vs. 55%; and 5-year: 51% vs. 35%, P =0.047). In conclusion, unlike ampullary-duodenal carcinomas, IAPNs are often (44.4%) predominantly nonintestinal and commonly (94%) invasive, displaying aggressive features and LN metastasis even when minimally invasive, all of which render them less amenable to ampullectomy. However, their prognosis is still better than that of the "ampullary-ductal" carcinomas, with which IAPNs are currently grouped in CAP protocols (while IAPNs are kindreds of intraductal tumors of the pancreatobiliary tract, the latter represents the ampullary counterpart of pancreatic adenocarcinoma/cholangiocarcinoma).

Intra-ampullary and Periampullary Carcinoma: Clinicopathological Comparison and Survival Outcomes

Introduction The ampulla of Vater is a structure in the duodenal wall in which the biliary and pancreatic ducts open. Malignant epithelial tumors arising at this site are commonly referred to as ampullary adenocarcinomas. In this study, we compared the clinicopathological features of intra-ampullary and periampullary carcinomas, including survival outcomes. Methods This retrospective cross-sectional study was conducted at the Department of Pathology, Liaquat National Hospital. All radiologically suspected cases or biopsy-proven (endoscopic biopsy) cases of intra-ampullary/periampullary carcinoma were included in the study. All patients underwent surgical resection (Whipple's procedure/pancreatoduodenectomy). The classification of intra-ampullary and periampullary carcinomas was performed according to the College of American Pathologists (CAP) guidelines. Results Among the 188 case studies, most (61.7%, n = 116) were males, with a median age of 55 years. Most tumors were of the pancreatobiliary subtype (57.4%, n = 108). Similarly, intra-ampullary carcinoma was more common than periampullary carcinoma (61.7% vs. 38.3%). Intra-ampullary carcinoma showed a higher extent of involvement of adjacent structures, a higher frequency of perineural invasion, and a higher nodal stage than periampullary carcinoma. Similarly, the median disease-specific survival of intra-ampullary carcinoma was significantly lower (46 months) than that of periampullary carcinoma (53.5 months). Conclusion We found a higher incidence of intra-ampullary carcinoma in our study. In addition, intra-ampullary carcinoma had a worse survival rate and was associated with poorer pathological parameters, such as perineural invasion and higher nodal and tumor stages than periampullary carcinoma.

Prognostic significance of histologic phenotype in periampullary adenocarcinomas

Background

Periampullary adenocarcinomas typically exhibit either intestinal or pancreatobiliary (PB) differentiation, and the type of differentiation may be prognostically more important than the anatomic site of origin. This study aimed to evaluate prognostic significance of histological type of periampullary carcinomas.

Methods

Microscopic slides from 110 consecutive pancreatoduodenectomies performed between 2010 and 2020 were reviewed and classified as intestinal or PB type. Clinicopathological factors were compared between PB-(n=93) and intestinal-type (n=17) differentiation.

Results

The intestinal type included significantly more patients with well-differentiated histology (35.3% vs. 11.8%, p=0.001) and fewer patients with perineural invasion (41.2% vs. 76.4%, p=0.029), advanced T stage (> T3; 41.2% vs.74.2%, p=0.007), and systemic recurrence (71.4% vs. 92.9%, p=0.005) than PB type. The 5-year-overall survival rate of intestinal-type was significantly higher than that of PB-type (58.8% vs. 20.4%, p=0.003). When pancreatic cancer was separately analyzed, the intestinal type showed the best 5-year-overall survival rate, with no significant difference between the PB types excluding PDAC and PDAC (39.4% vs. 19.2%, p=0.148). In multivariate analysis, curative resection (hazard ratio, 0.417; 95% CI, 0.219-0.792, p=0.008) was the only significant prognostic factor.

Conclusion

Although intestinal histologic phenotype was not an independent prognostic factor on multivariate analysis, it showed pathologic features associated with better survival, while the PB type showed more aggressive tumor biology and consequently worse survival. Further studies are needed to demonstrate the prognostic significance of histologic phenotype.

Feasibility of new-generation endocytoscopy for the real-time diagnosis of ampullary lesions: A pilot study (with video)

BACKGROUND AND AIM

An early and accurate diagnosis of ampullary neoplasia is crucial; however, sampling bias is still a major concern. New-generation endocytoscopy enables real-time visualization of cellular structures and enables an accurate pathological prediction; however, its feasibility for small ampullary lesions has never been investigated.

METHODS

We developed a novel endocytoscopic (EC) classification system for ampullary lesions after an expert review and agreement from five experienced endoscopists and one pathologist. We then consecutively enrolled a total of 43 patients with an enlarged ampulla (< 3 cm), all of whom received an endocytoscopic examination. The feasibility of endocytoscopy was evaluated, and the performance of the EC classification system was then correlated with the final histopathology.

RESULTS

In five cases (11.6%), the endocytoscope could not approach the ampulla, and these cases were defined as technical failure. Among the remaining 38 patients, 8 had histopathology-confirmed adenocarcinoma, 15 had adenoma, and 15 had non-neoplastic lesions. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the EC classification system to diagnose ampullary neoplasias were 95.7%, 86.7%, 91.7%, 92.9%, and 92.1%, respectively. Moreover, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the EC classification to diagnose ampullary cancer were 62.5%, 100%, 100%, 90.9%, and 92.1%, respectively. One case with intra-ampullary papillary-tubular carcinoma was classified as having a non-neoplastic lesion by endocytoscopy.

CONCLUSIONS

Endocytoscopy and the novel EC classification system demonstrated good feasibility to discriminate ampullary neoplasias from non-neoplastic lesions and may be useful for optical biopsies of clinically suspicious ampullary lesions.

The road to tailored adjuvant chemotherapy for all four non-pancreatic periampullary cancers: An international multimethod cohort study

BACKGROUND

Despite differences in tumour behaviour and characteristics between duodenal adenocarcinoma (DAC), the intestinal (AmpIT) and pancreatobiliary (AmpPB) subtype of ampullary adenocarcinoma and distal cholangiocarcinoma (dCCA), the effect of adjuvant chemotherapy (ACT) on these cancers, as well as the optimal ACT regimen, has not been comprehensively assessed. This study aims to assess the influence of tailored ACT on DAC, dCCA, AmpIT, and AmpPB.

PATIENTS AND METHODS

Patients after pancreatoduodenectomy for non-pancreatic periampullary adenocarcinoma were identified and collected from 36 tertiary centres between 2010 - 2021. Per non-pancreatic periampullary tumour type, the effect of adjuvant chemotherapy and the main relevant regimens of adjuvant chemotherapy were compared. The primary outcome was overall survival (OS).

RESULTS

The study included a total of 2866 patients with DAC (n = 330), AmpIT (n = 765), AmpPB (n = 819), and dCCA (n = 952). Among them, 1329 received ACT, and 1537 did not. ACT was associated with significant improvement in OS for AmpPB (P = 0.004) and dCCA (P < 0.001). Moreover, for patients with dCCA, capecitabine mono ACT provided the greatest OS benefit compared to gemcitabine (P = 0.004) and gemcitabine - cisplatin (P = 0.001). For patients with AmpPB, no superior ACT regime was found (P > 0.226). ACT was not associated with improved OS for DAC and AmpIT (P = 0.113 and P = 0.445, respectively).

DISCUSSION

Patients with resected AmpPB and dCCA appear to benefit from ACT. While the optimal ACT for AmpPB remains undetermined, it appears that dCCA shows the most favourable response to capecitabine monotherapy. Tailored adjuvant treatments are essential for enhancing prognosis across all four non-pancreatic periampullary adenocarcinomas.

Prognostic Impact of Mucin Expression in Curatively Resected Ampulla of Vater Cancer

Introduction: Mucins play a pivotal role in epithelial carcinogenesis; however, their role remains elusive in ampulla of Vater (AoV) cancer, regardless of histological subtype. Therefore, we investigated the clinical significance of MUC1, MUC2, MUC5AC, and MUC6 expression in AoV cancer. Methods: Using samples from 68 patients with AoV cancer, we performed immunohistochemical staining for MUC1, MUC2, MUC5AC, and MUC6 using a tissue microarray. Subsequently, we analyzed their expression patterns in relation to clinicopathological parameters and patient outcomes. Results: Of the patients, 98.5% exhibited positive expression for MUC1, while MUC2, MUC5AC, and MUC6 were expressed in 44.1%, 47.1%, and 41.2% of the patients, respectively. Correlation analyses between mucin expression and clinicopathological factors revealed no significant associations, except between MUC5AC expression and N stage. Univariate analysis demonstrated significant associations between MUC5AC expression and overall survival (OS). Multivariate analysis further confirmed that MUC5AC expression was a significant predictor of OS, along with the N stage. However, MUC5AC expression was not meaningfully associated with recurrence-free survival (RFS). The patients positive for MUC5AC expression had a considerably shorter OS than those with negative expression. Conclusions: Our study provides insights into the clinical impact of mucins on AoV cancer, regardless of the histological subtype. Although MUC1 expression is universal, MUC5AC expression is a significant prognostic indicator that correlates with lymph node metastasis and poor OS. These results emphasize the possible utility of MUC5AC as a biomarker for extensive lymph node dissection and the prognostic evaluation of patients with AoV cancer.

Mutational profiling of 103 unresectable pancreatic ductal adenocarcinomas using EUS-guided fine-needle biopsy

Background and Objective

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers, with a 5-year survival rate of around 9%. Only 20% are candidates for surgery. Most unresectable patients undergo EUS-guided fine-needle biopsy (EUS-FNB) for diagnosis. Identification of targetable mutations using next-generation sequencing (NGS) is increasingly requested. Data on feasibility of EUS-FNB for NGS and knowledge regarding mutational profile of unresectable PDAC are scarce. We evaluated the "technical yield" of EUS-FNB for NGS in unresectable PDAC: relative fraction of diagnostic EUS-FNBs meeting technical criteria. We also investigated the "molecular yield": relative fraction of EUS-FNBs included in NGS containing sufficient DNA for detection of at least one mutation. Furthermore, we determined the relative frequency of cancer-associated mutations in unresectable PDAC.

Patients and Methods

Formalin-fixed and paraffin-embedded EUS-FNBs diagnostic of unresectable PDAC and fulfilling these criteria were included (n = 105): minimum 3-mm2 tissue, minimum of 2-mm2 tumor area, and minimum 20% relative tumor area. NGS was performed using Ion GeneStudio S5 Prime System and Oncomine™ Comprehensive Assay v.3 including 161 cancer-related genes.

Results

Technical yield was 48% (105/219) and molecular yield was 98% (103/105). Most frequently mutated genes were KRAS (89.3%) and TP53 (69.9%), followed by CDKN2A (24.3%), ARID1A (9.7%), SMAD4 (7.8%), TSC2 (7.8%), and CCND3 (6.8%).

Conclusion

EUS-FNB for NGS of unresectable PDAC is feasible. Our technical criteria for NGS, using leftovers in formalin-fixed and paraffin-embedded blocks after routine pathology diagnosis, were met by around half of EUS-FNBs. Almost all EUS-FNBs fulfilling the technical criteria yielded a successful NGS analysis.

A Case of Breast Cancer Metastasizing to the Ampulla of Vater

Secondary tumors of the ampulla of Vater are exceedingly rare and associated with relatively poor prognosis. Tumors of the ampulla are classified into four distinct subtypes based on the location and involvement of surrounding structures. Most reported cases are of renal cell or malignant skin melanoma primary with only five previously reported cases of breast primary found in a literature review. We present a 72-year-old woman with metastatic breast cancer to the ampulla of Vater as well as multiple bones. She had a history of breast cancer status post bilateral mastectomy and chemo 27 years prior. She presented to the hospital with altered mental status and was found to have an acute liver injury. Magnetic resonance cholangiopancreatography revealed a distended gallbladder and an indeterminate left retroperitoneal mass concerning for cystic or necrotic lymphadenopathy. Endoscopy then showed an edematous and erythematous periampullary region, which was biopsied and returned positive for carcinoma. Immunohistochemical staining of the retroperitoneal mass returned positive for keratin, estrogen receptor, GATA3, and MOC31 and negative for progesterone receptor, WT1, calretinin, and E-cadherin. The periampullary region's immunohistochemistry returned positive for pankeratin (AE1/AE3) and CD138 and negative for CD45 and S100, supporting a diagnosis of primary breast carcinoma. The average time from diagnosis of breast cancer to metastasis was found to be 2.5 years. Endoscopic visual presentation of metastatic cancer to the ampulla is indistinguishable from that of primary cancers. Thus, a biopsy with cytology and immunohistochemical analysis is necessary for diagnosis. Management of secondary ampullary tumors requires a multidisciplinary team, including gastroenterology, surgery, oncology, and often palliative care. Secondary tumors have been found to be treated by any combination of Whipple's resections, chemotherapy, drainage/stenting, and endoscopic ampullectomy.

PD-L1 Expression in Ampullary Adenocarcinoma

INTRODUCTION

Ampullary adenocarcinoma is a rare neoplasm often treated by the complex Whipple's procedure. Several histological factors predict poor prognosis including pancreatobiliary morphology, presence of lymphovascular, perineural invasion and local or distant metastasis. Systemic therapy with gemcitabine, 5-fluorouracil regimens are given with variable benefits. Immunotherapy checkpoint inhibitors have shown beneficial anti-tumor effects in several carcinomas, the most remarkable being in non-small cell lung cancer. Administration of these novel drugs is based on immunohistochemical expression (which may or may not be indicative of response to therapy) along with meticulous decision making by the multidisciplinary team. Immunohistochemistry (IHC) is an effective means of immune marker demonstration and has been used in various tumor types for predictive and prognostic purposes.

METHODS

PD-L1 IHC (clone E1L3N) was applied in 101 cases of ampullary adenocarcinoma. Tumor infiltrating lymphocytes were also evaluated. The immunoreactivity was assessed and categorized into following staining thresholds: <1%, <5%, <10% and ≥10% for tumor cells (membranous and/or cytoplasmic staining pattern), and 5% and 10% cut-offs for immune cells.

RESULTS

We found that at a 10% cut-off, 73.3% (74/101) patients were men (P  =  .006) older than 50 years of age (P < .001) presenting with a tumor measuring <3 cm (P  =  .001). It was significantly associated with intestinal differentiation (P  =  .004) and grade 1 tumors (P  =  .001). Twelve patients presented with recurrence as well (P  =  .03).

CONCLUSION

In the context of ampullary adenocarcinoma, this study highlights the positivity observed with the PD-L1 IHC clone E1L3N at different thresholds, with the particularly stronger associations being evident at a 10% cut-off.

Assessing the genomic feature of Chinese patients with ampullary adenocarcinoma: potential therapeutic targets

BACKGROUNDS

Ampullary adenocarcinoma (AMPAC) is a rare malignancy, treated as pancreatic or intestinal cancer based on its histologic subtype. Little is known about the genomic features of Chinese patients with AMPAC.

MATERIALS AND METHODS

We enrolled 145 Chinese AMPAC patients in our local cohort and performed a compressive somatic and germline genetic testing using a 156 gene panel. Expression of PD-L1 (clone 28 - 8) was also assessed in tumor specimens from 64 patients.

RESULTS

The frequency of genetic alterations (GAs) in Chinese patients with AMPAC was found to be distinctive, with TP53, KRAS, SMAD4, APC, CTNNB1, ARID1A, and CDKN2A emerged as the most frequently mutated genes. Comparing with Western patients, significant differences were observed in the prevalence of PIK3CA and ARID2. Furthermore, the incidence of MSI-H was lower in the Chinese cohort, with only two patients identified as MSI-H. Conversely, 11 patients (8.27%) had pathogenic/likely pathogenic germline alterations, all of which were in the DNA damage response (DDR) pathway. In our cohort, 34.48% (22/64) of patients exhibited positive PD-L1 expression in tumor cells, and this expression was associated with GAs in CTNNB1 and BLM. Importantly, over three-fourths of Chinese AMPAC patients in our study had at least one actionable GA, with more than one-fifth of them having actionable GAs classified as Level 3. These actionable GAs were primarily involved in the DDR and PI3K pathways. Notably, GAs in the DDR pathway were detected in both Chinese and Western patients, and regardless of their functional impact, these alterations demonstrated enhanced overall survival rates and higher tumor mutational burden (TMB) levels.

CONCLUSION

These findings underscore the distinct genomic landscape of Chinese AMPAC patients and highlight the potential for targeted therapies based on the identified GAs.

Different Periampullary Types and Subtypes Leading to Different Perioperative Outcomes of Pancreatoduodenectomy: Reality and Not a Myth; An International Multicenter Cohort Study

This international multicenter cohort study included 30 centers. Patients with duodenal adenocarcinoma (DAC), intestinal-type (AmpIT) and pancreatobiliary-type (AmpPB) ampullary adenocarcinoma, distal cholangiocarcinoma (dCCA), and pancreatic ductal adenocarcinoma (PDAC) were included. The primary outcome was 30-day or in-hospital mortality, and secondary outcomes were major morbidity (Clavien-Dindo 3b≥), clinically relevant post-operative pancreatic fistula (CR-POPF), and length of hospital stay (LOS). Results: Overall, 3622 patients were included in the study (370 DAC, 811 AmpIT, 895 AmpPB, 1083 dCCA, and 463 PDAC). Mortality rates were comparable between DAC, AmpIT, AmpPB, and dCCA (ranging from 3.7% to 5.9%), while lower for PDAC (1.5%, p = 0.013). Major morbidity rate was the lowest in PDAC (4.4%) and the highest for DAC (19.9%, p < 0.001). The highest rates of CR-POPF were observed in DAC (27.3%), AmpIT (25.5%), and dCCA (27.6%), which were significantly higher compared to AmpPB (18.5%, p = 0.001) and PDAC (8.3%, p < 0.001). The shortest LOS was found in PDAC (11 d vs. 14-15 d, p < 0.001). Discussion: In conclusion, this study shows significant variations in perioperative mortality, post-operative complications, and hospital stay among different periampullary cancers, and between the ampullary subtypes. Further research should assess the biological characteristics and tissue reactions associated with each type of periampullary cancer, including subtypes, in order to improve patient management and personalized treatment.

Ampullary Adenocarcinoma: A Review of the Mutational Landscape and Implications for Treatment

Ampullary carcinomas represent less than 1% of all gastrointestinal malignancies with an incidence of approximately 6 cases per 1 million. Histologic examination and immunohistochemistry have been traditionally used to categorize ampullary tumors into intestinal, pancreatobiliary or mixed subtypes. Intestinal-subtype tumors may exhibit improved survival versus the pancreatobiliary subtype, although studies on the prognostic value of immunomorphologic classification have been inconsistent. Genomic classifiers hold the promise of greater reliability, while providing potential targets for precision oncology. Multi-institutional collaboration will be necessary to better understand how molecular classification can guide type and sequencing of multimodality therapy.

Tumor Microenvironment Prognostic Risk and Its Association With MUC5AC in Ampullary Carcinoma

CONTEXT.—

The tumor-host interaction in the tumor microenvironment (TME) affects the prognosis of patients with malignant tumors. TME assessed via tumor budding (BD) and tumor-infiltrating lymphocyte (TIL) had a prognostic impact in patients with nonampullary small intestinal and colorectal carcinomas. In ampullary carcinoma (AC), MUC5AC was recently revealed as a significant prognosticator, but studies about the TME have not been conducted.

OBJECTIVE.—

To assess TME-based prognostic risk in AC.

DESIGN.—

We generated a collective TME risk index based on high-grade BD at the invasive front (BD3) and high density of stromal-TIL (>5%) in 64 surgically resected ACs. We evaluated its predictive values for overall survival (OS) and recurrence-free survival (RFS). We also investigated the relationship of TME to MUC5AC expression.

RESULTS.—

TME prognostic risk index was classified into low-risk (BDLow/TILHigh; 26 of 64; 41%), intermediate-risk (BDLow/TILLow or BDHigh/TILHigh; 23; 36%), and high-risk (BDHigh/TILLow; 15; 23%) groups. Higher TME prognostic risk was associated with higher tumor grade (P = .03), lymphovascular invasion (P = .05), and MUC5AC immunopositivity (P = .02). TME prognostic risk index displayed better predictive ability for both OS (53.9 versus 46.1 versus 42.2) and RFS (24.8 versus 16.9 versus 15.3) than BD or TIL alone. In multivariate analysis, TME prognostic risk index was an independent prognosticator for OS (P = .003) and RFS (P = .03).

CONCLUSIONS.—

TME risk index in combination with BD and TIL was a stronger predictor of prognostic risk stratification than either BD or TIL alone for both OS and RFS in patients with AC. MUC5AC may modulate the interaction between tumor cells and immunity toward enhancing invasiveness in TME.

The clinical implication of minimally invasive versus open pancreatoduodenectomy for non-pancreatic periampullary cancer: a systematic review and individual patient data meta-analysis

BACKGROUND

Most studies on minimally invasive pancreatoduodenectomy (MIPD) combine patients with pancreatic and periampullary cancers even though there is substantial heterogeneity between these tumors. Therefore, this study aimed to evaluate the role of MIPD compared to open pancreatoduodenectomy (OPD) in patients with non-pancreatic periampullary cancer (NPPC).

METHODS

A systematic review of Pubmed, Embase, and Cochrane databases was performed by two independent reviewers to identify studies comparing MIPD and OPD for NPPC (ampullary, distal cholangio, and duodenal adenocarcinoma) (01/2015-12/2021). Individual patient data were required from all identified studies. Primary outcomes were (90-day) mortality, and major morbidity (Clavien-Dindo 3a-5). Secondary outcomes were postoperative pancreatic fistula (POPF), delayed gastric emptying (DGE), postpancreatectomy hemorrhage (PPH), blood-loss, length of hospital stay (LOS), and overall survival (OS).

RESULTS

Overall, 16 studies with 1949 patients were included, combining 928 patients with ampullary, 526 with distal cholangio, and 461 with duodenal cancer. In total, 902 (46.3%) patients underwent MIPD, and 1047 (53.7%) patients underwent OPD. The rates of 90-day mortality, major morbidity, POPF, DGE, PPH, blood-loss, and length of hospital stay did not differ between MIPD and OPD. Operation time was 67 min longer in the MIPD group (P = 0.009). A decrease in DFS for ampullary (HR 2.27, P = 0.019) and distal cholangio (HR 1.84, P = 0.025) cancer, as well as a decrease in OS for distal cholangio (HR 1.71, P = 0.045) and duodenal cancer (HR 4.59, P < 0.001) was found in the MIPD group.

CONCLUSIONS

This individual patient data meta-analysis of MIPD versus OPD in patients with NPPC suggests that MIPD is not inferior in terms of short-term morbidity and mortality. Several major limitations in long-term data highlight a research gap that should be studied in prospective maintained international registries or randomized studies for ampullary, distal cholangio, and duodenum cancer separately.

PROTOCOL REGISTRATION

PROSPERO (CRD42021277495) on the 25th of October 2021.

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.

Intra-ampullary papillary-tubular neoplasm

Video 1Cholangioscopic examination of the ampullary channel and extrahepatic bile duct.

Medullary carcinoma of the ampulla has distinct clinicopathologic characteristics including common association with microsatellite instability and PD-L1 expression

Medullary carcinomas have not yet been fully characterized in the ampulla. Here, 359 ampullary carcinomas (ACs) were reviewed and 11 medullary-type carcinomas (3%) were found and analyzed. In addition to the diagnostic medullary pattern, 6 showed focal mucinous and 8 had focal abortive gland-like formations. They occurred in younger patients (57 versus 65 y; P = .02), had larger invasion size (mean, 3.2 versus 1.9 cm; P = .01), formed nodular polypoid or plaque-like tumors, and often lacked preinvasive component. In addition to the lymphoplasmacytic infiltrates, they also had prominent eosinophils in 5 of 11 cases. Eight were papilla Vateri-NOS (not otherwise specified) tumors, 2 were ampullary-duodenal origin, 1 had a minor intra-ampullary papillary tubular neoplasm component, and none were ampullary-ductal. Although they had pushing-border infiltration, perineural and vascular invasion was common. They were strongly associated with DNA mismatch repair (MMR) protein deficient (7/11, 64%). The 5-yr survival rate (53%) appeared to be comparable with, and perhaps even better than that of nonmedullary ACs (47%), although this did not reach statistical significance (P = .47). Programmed cell death ligand-1 (PD-L1) expression levels were assessed in 8, and all 4 that were MMR deficient were positive both by combined positive score (CPS) ≥1 and tumor proportion score (TPS) ≥1, and of the 4 MMR proficient cases, 3 were positive by CPS; 2 by TPS. Overall, only 1 of the 8 available for analysis failed to show PD-L1 positivity by CPS. In contrast, nonmedullary MMR-deficient carcinomas expressed PD-L1 in only 33% of tumors by CPS, and none by TPS. One medullary carcinoma was also EBV associated. Unlike 'medullary carcinomas' of the kidney, INI1 was retained in all 8 cases tested. In conclusion, medullary carcinomas are 3% of ACs, have a strong association with MMR-D, and may be less aggressive despite their larger size. PD-L1 expression appears to be closely associated with medullary ACs regardless of MMR status, and thus targeted therapies can be considered for all medullary carcinomas of this site.

Surgical treatment of duodenal adenocarcinoma: ampullary vs. non-ampullary, short- and long-term outcomes

BACKGROUND

The aim of this study was to evaluate symptoms, diagnostic methods, short- and long-term outcomes of surgical treatment in patients with duodenal adenocarcinoma.

PATIENTS AND METHODS

A single center, retrospective, observational study of 52 consecutive patients with duodenal adenocarcinoma operated on with curative intent between 2006 - 2019. Duodenectomy as part of a hemipancreatoduodenectomy or total pancreatectomy procedure was performed for ADAC (ampullary duodenal/intestinal adenocarcinoma) or NADAC (non-ampullary duodenal adenocarcinoma).

RESULTS

Prevailing symptoms were obstructive jaundice in the ADAC group (P<0.0001) and bleeding in the NADAC group (P=0.005), with larger tumor size in patients with NADAC (P=0.001). Complication rate, morbidity and mortality were comparable. Primary total pancreatoduodenectomy predominated in the NADAC group, 16.6% vs. 2.9%, and salvage completion pancreatectomy in the ADAC group, 6% vs. 0%. Significant prognostic factors for OS were perineural invasion (P=0.006) and adjuvant chemotherapy (P=0.045) in the ADAC group, and for DFS the total number of resected lymph nodes (P=0.042) and lymph node ratio (P=0.031) in the NADAC group. Median OS is 21 months and 5-year survival 27.3% in the NADAC group and 41.5 months and 52% in the ADAC group.

CONCLUSION

Ampullary duodenal/intestinal adenocarcinomas are smaller than non-ampullary at diagnosis, with a higher rate of lymph node metastases, but with a better prognosis and long-term outcome in the presented cohort. Oral localisation of NADAC prevailed in the present cohort. Perineural invasion and postoperative oncological therapy are significant prognostic factors for OS in ADAC, but the total number of lymph nodes and lymph node ratio are significant prognostic factors for DFS in NADAC.

Analysis of lymph node spread and its prognostic significance in ampullary adenocarcinoma: A retrospective study

Background

Nodal status is a vital prognostic factor for ampullary adenocarcinoma. This study was designed to evaluate the clinical significance of the positive nodes in this disease.

Methods

Data from 110 patients who underwent curative pancreatoduodenectomy for ampullary adenocarcinoma between January 2007 and December 2018 were retrospectively collected and analyzed.

Results

The median number of lymph nodes per patient was 32 (20–46). Metastatic lymph nodes were found in 84 (76.4%) patients. In patients with positive nodules, the most commonly involved nodes were the #13 (80.1%) and #17 (78.6%) nodes, followed by #12 (69.0%) and #8 nodes (57.1%). Patients with 3–4 positive nodes among #13, #17, #12, and #8 had lower survival rates than those with 0 or 1–2 nodes.

Conclusion

Ampullary adenocarcinoma commonly spreads to #13, #17, #12, and #8 lymph nodes. These nodes affected the patients' survival rates dramatically.

Epidemiology, Risk Factors and Diagnosis of Small Bowel Adenocarcinoma

Simple Summary

Small bowel adenocarcinoma is a rare tumor. Diagnosis is often obtained at an advanced stage and prognosis remains poor. The aim of this review is to report the recent epidemiological and risk factor data related to small bowel adenocarcinoma. New diagnostic tools are also described in this review.

Abstract

Adenocarcinomas of the small intestine are rare tumors but their incidence is increasing. There is a slight male predominance. The median age at diagnosis is the 6th decade. The most frequent primary location is the duodenum. There is no clearly identified environmental risk factor, but adenocarcinomas of the small intestine are associated in almost 20% of cases with predisposing diseases (Crohn’s disease, Lynch syndrome, familial adenomatous polyposis, Peutz–Jeghers syndrome and celiac disease).

Predictors and Recurrence Patterns After Radical Surgery in Ampulla of Vater Cancer: Comparative Analysis Between Early and Late Recurrence

Objective

Tumor recurrence remains the main dilemma after surgical treatment of ampulla of Vater carcinoma. This study was designed to identify the prognostic factors and evaluate the recurrence patterns of ampulla of Vater cancer.

Methods

A total of 286 patients who underwent surgical resection of ampulla of Vater cancer in two medical centers from January 2000 to October 2016 were collected. Data on clinicopathologic factors, survival rate, and recurrence patterns were retrospectively analyzed.

Results

A total of 158 patients (55.2%) survived without evidence of recurrence (non-recurrence), whereas 65 (22.7%) and 63 patients (22.1%) suffered from recurrence of the disease within 12 months (early recurrence) and after 12 months (late recurrence), respectively. Early-recurrence patients exhibited a more advanced disease (advanced tumor stage, lymph node involvement, pancreas invasion, and late TNM stage) than late-recurrence patients. The first or primary location of cancer recurrence in 33 patients (25.8%) was locoregional. Metastasis developed in the liver in 30 patients (23.4%), peritoneum in 13 patients (10.2%), lungs in 10 patients (7.8%), and para-aortic or superior mesenteric artery lymph node in 10 patients (7.8%). Multiple metastases were observed in 26 patients (20.3%).

Conclusion

The most common patterns of postoperative recurrence are locoregional and recurrent liver metastasis. The recurrence patterns with the worst prognosis are peritoneal and multiple metastases.

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.

Mixed neuroendocrine–nonneuroendocrine neoplasms of the gastrointestinal system: An update

Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs) of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment. Over the years, the diagnostic criteria, classification, and clinical behavior of these tumors have been the subjects of ongoing debate, and the various changes in their nomenclature have strengthened the challenges associated with MiNENs. This review is performed to provide an understanding of the key factors involved in the evolution of the designation of these tumors as MiNEN, highlight the current diagnostic criteria, summarize the latest data on pathogenesis and provide information on available treatments. Moreover, this work seeks to increase the awareness about these rare neoplasms by presenting the clinicopathological features and prognostic factors that play important roles in their behavior and discussing their different regions of origin in the gastrointestinal system (GIS). Currently, the MiNEN category also includes tumors in the GIS with a nonneuroendocrine component and epithelial tumors other than adenocarcinoma, depending on the organ of origin. Diagnosis is based on the presence of both morphological components in more than 30% of the tumor. However, this value needs to be reconfirmed with further studies and may be a limiting factor in the diagnosis of MiNEN by biopsy. Furthermore, available clinicopathological data suggest that the inclusion of amphicrine tumors in the definition of MiNEN is not supportive and warrants further investigation. The diagnosis of these tumors is not solely based on immunohistochemical findings. They are not hybrid tumors and both components can act independently; thus, careful grading of each component separately is required. In addition to parameters such as the metastatic state of the tumor at the time of diagnosis and the feasibility of surgical resection, the aggressive potential of both components has paramount importance in the choice of treatment. Regardless of the organ of origin within the GIS, almost MiNENs are tumors with poor prognosis and are frequently encountered in the elderly and men. They are most frequently reported in the colorectum, where data from molecular studies indicate a monoclonal origin; however, further studies are required to provide additional support for this origin.

Prognostic Factors and Clinical Characteristics of Duodenal Adenocarcinoma With Survival: A Retrospective Study

Background

To evaluate the clinical risk factors that influence the overall survival in patients with duodenal adenocarcinoma (DA) after tumor resection.

Methods

This study retrospectively analyzed 188 patients who underwent tumor resection for DA between January 2005 and June 2020 at Xiangyang Central Hospital.

Results

The median survival of the patients who underwent resectional operation was 54 months, longer than of those who underwent palliative surgery (20.8 months) (2,916.17; 95% CI, 916.3−9,280.5; p < 0.001). Survival of non-ampullary duodenal carcinoma patients (50.3 months; 95% CI, 39.7−61.8) was similar to that of ampullary duodenal carcinoma patients (59.3 months; 95% CI, 38.6−66.7) but was significantly better than that of papillary adenocarcinoma patients (38.9 months; 95% CI, 29.8−54.8; p = 0.386). Those with intestinal-type ductal adenocarcinomas had a longer median overall survival than those with the gastric type (61.8 vs. 46.7 months; p < 0.01) or pancreatic type (32.2 months; p < 0.001). Clinical DA samples had significantly diverse expressions of ATG12, IRS2, and IGF2. Higher expressions of the ATG12 and IRS2 proteins were significantly correlated with worse survival. Multivariate Cox regression analysis revealed that lymph node metastasis (hazard ratio (HR), 6.44; 95% CI, 3.68−11.27; p < 0.0001), margin status (HR, 4.94; 95% CI, 2.85−8.54; p < 0.0001), and high expression of ATG12 (HR, 1.89; 95% CI, 1.17−3.06; p = 0.0099) were independent prognostic factors negatively associated with survival in patients undergoing curative resection. There was no survival difference between the groups with ampullary, non-ampullary, and papillary adenocarcinomas treated with adjuvant chemotherapy (p = 0.973).

Conclusion

Gastric/pancreatic type, high expression of ATG12, lymph node metastases, and margin status were negative prognosticators of survival in patients with DAs than in those with tumor anatomical location. Curative resection is the best treatment option for appropriate patients.

Towards a More Standardized Approach to Pathologic Reporting of Pancreatoduodenectomy Specimens for Pancreatic Ductal Adenocarcinoma: Cross-continental and Cross-specialty Survey From the Pancreatobiliary Pathology Society Grossing Working Group

In recent literature and international meetings held, it has become clear that there are significant differences regarding the definition of what constitutes as margins and how best to document the pathologic findings in pancreatic ductal adenocarcinoma. To capture the current practice, Pancreatobiliary Pathology Society (PBPS) Grossing Working Group conducted an international multispecialty survey encompassing 25 statements, regarding pathologic examination and reporting of pancreatic ductal adenocarcinoma, particularly in pancreatoduodenectomy specimens. The survey results highlighted several discordances; however, consensus/high concordance was reached for the following: (1) the pancreatic neck margin should be entirely submitted en face, and if tumor on the slide, then it is considered equivalent to R1; (2) uncinate margin should be submitted entirely and perpendicularly sectioned, and tumor distance from the uncinate margin should be reported; (3) all other surfaces (including vascular groove, posterior surface, and anterior surface) should be examined and documented; (4) carcinoma involving separately submitted celiac axis specimen should be staged as pT4. Although no consensus was achieved regarding what constitutes R1 versus R0, most participants agreed that ink on tumor or at and within 1 mm to the tumor is equivalent to R1 only in areas designated as a margin, not surface. In conclusion, this survey raises the awareness of the discordances and serves as a starting point towards further standardization of the pancreatoduodenectomy grossing and reporting protocols.

Identification and prevalence of potentially therapeutic targetable variants of major cancer driver genes in ampullary cancer patients in India through deep sequencing

Ampulla is a complex region located at the confluence of pancreatic and common bile duct and intestinal epithelium. Tumors arising in this region are anatomically and morphologically heterogenous, however they show unique as well as overlapping molecular features. Cancers of both these anatomic sites share morphological as well as genetic profile despite having few unique differences. Targeted therapies are currently emerging as one of the demanding approaches for treatment in most cancer types especially for malignant epithelial tumors and therefore genetic profiling of cancers is the key for identification of potentially therapeutic targetable mutations to know their prevalence and prognostic impact. We studied 97 resected cases of formalin fixed paraffin-embedded AC by deep targeted sequencing using Ampliseq cancer hotspot panel comprising of 50 oncogenes and tumor suppressor genes. Potentially therapeutic targetable mutations were observed in 58/83 (70%) cases. Fourteen patients did not show any pathogenic mutation. TP53 (48.1%), KRAS (37.3%), APC (25.3%), SMAD4 (22.8%), MET (16.8%), CTNNB1 (15.6%) and PIK3CA (10.8%) were the major mutated potential therapeutic targets. KRAS mutation (43.2 Vs. 32.6%) was more prevalent in pancreatobiliary subtype, while TP53 (58.6 Vs 35.1), APC (36.9 Vs 10.8), SMAD4 (28.2 Vs 16.2), MET (21.7 Vs 10.8) and CTNNB1 (19.5 Vs 10.8) were more prevalent in intestinal subtype. WNT signaling pathway was the major altered pathway in intestinal subtype. These mutated genes and pathways may be targeted with currently available drugs and may be explored for future development of targetable agents to improve the disease course in patients of AC.

[Surgery for periampullary pancreatic cancer]

Periampulläre Neoplasien sind eine heterogene Gruppe verschiedener Tumorentitäten der periampullären Region, von denen das Pankreasadenokarzinom mit 60–70 % am häufigsten ist. Wie typisch für Pankreaskarzinome zeichnen sich periampulläre Pankreaskarzinome durch ein aggressives Wachstum und eine frühe systemische Progression aus. Aufgrund ihrer besonderen Lage in unmittelbarer Nähe zur Papilla Vateri treten Symptome in eher früherem Tumorstadium auf, sodass die Therapiemöglichkeiten und Prognose insgesamt günstiger sind als bei Pankreaskarzinomen anderer Lokalisation. Trotzdem unterscheiden sich die Therapieprinzipien bei periampullären Pankreaskarzinomen nicht wesentlich von den Standards bei Pankreaskarzinomen anderer Lokalisation. Ein potenziell kurativer Therapieansatz beim nichtmetastasierten periampullären Pankreaskarzinom ist multimodal und besteht aus der Durchführung einer partiellen Duodenopankreatektomie als radikale onkologische Resektion in Kombination mit einer systemischen, meist adjuvant verabreichten Chemotherapie. Bei Patienten mit günstigen prognostischen Faktoren kann hierdurch ein Langzeitüberleben erzielt werden. Zudem wurden mit der Weiterentwicklung der Chirurgie und Systemtherapie auch potenziell kurative Therapiekonzepte für fortgeschrittene, früher irresektable Tumoren etabliert, welche nun nach Durchführung einer neoadjuvanten Therapie oft einer Resektion zugeführt werden können. In diesem Beitrag werden die aktuellen chirurgischen Prinzipien der radikalen onkologischen Resektion periampullärer Pankreaskarzinome im Kontext der multimodalen Therapie dargestellt und ein Ausblick auf mögliche künftige Entwicklungen der Therapie gegeben.

Recent Advances in Digestive Tract Tumors: Updates From the 5th Edition of the World Health Organization "Blue Book"

CONTEXT.—

The World Health Organization Classification of Tumours: Digestive System Tumors, 5th edition, was published in 2019 and shows several impactful changes as compared with the 4th edition published in 2010. Changes include a revised nomenclature of serrated lesions and revamping the classification of neuroendocrine neoplasms. Appendiceal goblet cell adenocarcinoma is heavily revised, and intrahepatic cholangiocarcinoma is split into 2 subtypes. New subtypes of colorectal carcinoma and hepatocellular carcinoma are described. Precursor lesions are emphasized with their own entries, and both dysplastic and invasive lesions are generally recommended to be graded using a 2-tier system. Hematolymphoid tumors, mesenchymal tumors, and genetic tumor syndromes each have their own sections in the 5th edition. New hematolymphoid lesions include monomorphic epitheliotropic intestinal T-cell lymphoma; duodenal-type follicular lymphoma; intestinal T-cell lymphoma, not otherwise specified; and indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. This paper will provide an in-depth look at the changes in the 5th edition as compared with the 4th edition.

OBJECTIVE.—

To provide a comprehensive, in-depth update on the World Health Organization classification of digestive tumors, including changes to nomenclature, updated diagnostic criteria, and newly described entities.

DATA SOURCES.—

The 5th edition of the World Health Organization Classification of Tumours: Digestive System Tumours, as well as the 4th edition.

CONCLUSIONS.—

The World Health Organization has made many key changes in its newest update on tumors of the digestive system. Pathologists should be aware of these changes and incorporate them into their practice as able or necessary.

Adenomatous neoplasia in the papilla of Vater endoscopic and/or surgical resection?

BACKGROUND

Adenomatous neoplasia in the papilla of Vater needs to be resected in order not to progress. It can be challenging to distinguish between early ampullary malignant lesions and non-invasive adenomas, due to the overlap in symptoms and radiological findings. This retrospective study describes the different findings and treatment decisions taken prior to endoscopic and/or surgical resection of ampullary adenomatous lesions.

MATERIALS AND METHODS

Patients treated with endoscopic and/or surgical resection for suspected or verified ampullary adenomatous neoplasia, between January 2006 and July 2018, where pre-interventional cross-sectional imaging could not discern an obvious invasive, malignant tumor, were included. Findings were compared against the final diagnosis of the histopathological analysis on the resected specimen.

RESULTS

In total, 172 met the inclusion criteria. Patients were treated with either surgical resection (n = 96), endoscopic papillectomy (EP) (n = 55) or both (n = 21). The final diagnosis was in 48% ampullary adenocarcinoma, and the remaining had either ampullary adenoma (38%) or non-neoplastic lesions (14%). In patients where symptoms and cross-sectional imaging were suspicious for malignancy, but with no tissue samples that confirmed neoplasia prior to surgical resection, only 47% had adenocarcinoma. The remaining had either adenoma (9%) or non-neoplastic lesions (44%). Adenocarcinoma was revealed in 27% of the patients where endoscopic biopsies had shown adenoma. Patients with adenoma, treated with EP, were cured in 59%. However, 28% were after EP sent for further surgery due to ductal invasion or a finding of adenocarcinoma.

CONCLUSIONS

In patients with a suspicion of ampullary neoplasia on imaging, attempts should be made to get endoscopic tissue samples before deciding on a treatment strategy. If biopsies show ampullary adenoma, patients should be considered for EP, unless there are clear radiologic or endoscopic signs of malignancy. Patients with adenocarcinoma on endoscopic biopsies should undergo surgical resection.

Identification of PI3K-AKT signaling as the dominant altered pathway in intestinal type ampullary cancers through whole-exome sequencing

Background

The genetic landscape of intestinal (INT) and pancreatobiliary (PB) type ampullary cancer (AC) has been evolving with distinct as well as overlapping molecular profiles.

Methods

We performed whole-exome sequencing in 37 cases of AC to identify the targetable molecular profiles of INT and PB tumors. Paired tumor-normal sequencing was performed on the HiSeq 2500 Illumina platform.

Results

There were 22 INT, 13 PB, and two cases of mixed differentiation of AC that exhibited a total of 1,263 somatic variants in 112 genes (2–257 variants/case) with 183 somatic deleterious variants. INT showed variations in 78 genes (1–31/case), while PB showed variations in 51 genes (1–29/case). Targetable mutations involving one or more major pathways were found in 86.5% of all ACs. Mutations in APC, CTNNB1, SMAD4, KMT2, EPHA, ERBB, and Notch genes were more frequent in INT tumors, while chromatin remodeling complex mutations were frequent in PB tumors. In the major signaling pathways, the phosphoinositide 3-kinase (PI3)/AKT and RAS/mitogen-activated protein kinase (MAPK) pathways were significantly mutated in 70% of cases (82% INT, 46% PB, p = .023), with PI3/AKT mutation being more frequent in INT and RAS/MAPK in PB tumors. Tumor mutation burden was low in both differentiation types, with 1.6/Mb in INT and 0.8/Mb in PB types (p = .217).

Conclusions

The exome data suggest that INT types are genetically more unstable than PB and involve mutations in tumor suppressors, oncogenes, transcription factors, and chromatin remodeling genes. The spectra of the genetic profiles of INT and PB types suggested primary targeting of PI3/AKT in INT and RAS/RAF and PI3/AKT pathways in PB carcinomas.

Diagnosis of digestive system tumours

The WHO Classification of Tumours provides the international standards for the classification and diagnosis of tumours. It enables direct comparisons to be made between different countries. In the new fifth edition, the series has gone digital with the launch of a website as well as a series of books, known widely as the WHO Blue Books. The first volume to be produced is on the classification of Digestive System tumours, replacing the successful 2010 version. It has been rewritten and updated accordingly. This article summarises the major diagnostic innovations that have occurred over the last decade and that have now been incorporated in the classification. As an example, it incorporates the recently proposed classification of neuroendocrine tumours, based on the recognition that neuroendocrine tumours and carcinomas differ substantially in the genetic abnormalities that drive their growth, findings relevant to treatment selection and outcome prediction. Several themes have emerged during the production process. One is the importance of the progression from hyperplasia to dysplasia to carcinoma in the evolution of the malignant process. Advances in imaging techniques and endoscopy have resulted in enhanced access to precancerous lesions in the gastrointestinal and biliary tract, necessitating both changes in classification schema and clinical practice. Diagnosis of tumours is no longer the sole purview of pathologists, and some patients now receive treatment before tissue is obtained, based on clinical, radiological and liquid biopsy results. This makes the classification relevant to many disciplines involved in the care of patients with tumours of the digestive system.

A case report of mucinous adenocarcinoma derived from intra-ampullary papillary-tubular neoplasm with a malignant course

Background

Intra-ampullary papillary-tubular neoplasm (IAPN) has been classified as a Vater papillary tumor. The prognosis of IAPN is generally relatively good. Here, we describe a patient with a mucinous adenocarcinoma cluster in the Vater papilla of IAPN origin.

Clinical presentation

The patient was a 66-year-old man who was admitted to our hospital after a diagnosis of pancreatic head carcinoma based on a pancreatic duct dilatation found on abdominal ultrasound. CT showed a 40 mm lesion in the pancreatic head and expansion of the main pancreatic duct to a maximum diameter of 9 mm on the caudal side of the lesion. The extrahepatic bile duct had also expanded to a maximum diameter of 8 mm. PET/CT showed fluorodeoxyglucose (FDG) accumulation of SUV_max 6.02 that corresponded to the tumor in the pancreatic head, though it did not suggest distant metastasis. The patient was diagnosed with pancreatic head carcinoma T3 N0 M0 Stage IIA and underwent a pancreaticoduodenectomy. Pathology indicated that the tumor in the pancreatic head was a benign inflammatory lesion. On the other hand, the papillotubular tumor pervading the lumen in the duodenal papillary common channel met the criteria for IAPN, and a mucinous adenocarcinoma cluster found in the surrounding stroma suggested malignant transformation of IAPN. No metastasis to lymph nodes was demonstrated. With regard to the mucus phenotype of each lesion, the IAPN was MUC2 and MUC5AC positive, while the mucinous adenocarcinoma was MUC2-positive and MUC5AC-negative. In addition, CD10 was negative in both lesions, suggesting that mucus transformation from the gastric type to the intestinal type was a key element. A blood test 10 months after surgery showed increased CA19-9 (105 U/mL) and CEA (7.1 ng/mL). Abdominal CT showed multiple cystoid nodes in the liver, which were diagnosed as multiple liver metastases of mucinous adenocarcinoma transformed from the IAPN.

Conclusions

We reported a case with IAPN that developed in the Vater papilla, which took an extremely malignant course. IAPN generally has a good prognosis, but it is important to understand that a malignant course may occur.

Novel method for evaluating the indication for endoscopic papillectomy in patients with ampullary adenocarcinoma

This study aimed to determine the clinicopathological features of the subtypes of ampullary carcinoma (AC) to explore the indications for endoscopic papillectomy (EP) in early AC. Fifty-seven patients with AC who underwent curative resection were retrospectively reviewed. The 0/IA stages were significantly more common in the intestinal type (I-type) than in the mixed and pancreatobiliary type (M&PB-type) (90.7% vs 35.7%, P < 0.001). Tis/T1a tumors limited to the ampulla [Tis/T1a(ampulla)] were significantly more likely to be I-type than M&PB-type (74.4% vs 14.3%, P = 0.002). The tub1 rate was significantly higher in the I-type than in the M&PB-type (81.4% vs 35.7%, P = 0.001). In the I-type, the tub1 rate was significantly higher for Tis/T1a(ampulla) than for T1a tumors limited to the sphincter of Oddi (100% vs 42.9%, P = 0.004). These observations suggest that I-type AC with tub1 is an indication for EP. The concordance rate of pathological subtypes between endoscopic biopsy and resected specimens was high (κ = 0.8053, P < 0.001). Tis/T1a(ampulla) showed no lymphovascular or perineural invasion. An endoscopic imaging finding of early AC with I-type and tub1 on biopsy could be an indication for EP. Identifying the pathological subtype of AC by endoscopic biopsy could be a novel preoperative approach for evaluating the indications for EP.

Comprehensive characterisation of pancreatic ductal adenocarcinoma with microsatellite instability: histology, molecular pathology and clinical implications

OBJECTIVE

Recently, tumours with microsatellite instability (MSI)/defective DNA mismatch repair (dMMR) have gained considerable interest due to the success of immunotherapy in this molecular setting. Here, we aim to clarify clinical-pathological and/or molecular features of this tumour subgroup through a systematic review coupled with a comparative analysis with existing databases, also providing indications for a correct approach to the clinical identification of MSI/dMMR pancreatic ductal adenocarcinoma (PDAC).

DESIGN

PubMed, SCOPUS and Embase were searched for studies reporting data on MSI/dMMR in PDAC up to 30 November 2019. Histological and molecular data of MSI/dMMR PDAC were compared with non-MSI/dMMR PDAC and with PDAC reference cohorts (including SEER database and The Cancer Genome Atlas Research Network - TCGA project).

RESULTS

Overall, 34 studies with 8323 patients with PDAC were included in the systematic review. MSI/dMMR demonstrated a very low prevalence in PDAC (around 1%-2%). Compared with conventional PDAC, MSI/dMMR PDAC resulted strongly associated with medullary and mucinous/colloid histology (p<0.01) and with a KRAS/TP53 wild-type molecular background (p<0.01), with more common JAK genes mutations. Data on survival are still unclear.

CONCLUSION

PDAC showing typical medullary or mucinous/colloid histology should be routinely examined for MSI/dMMR status using specific tests (immunohistochemistry, followed by MSI-PCR in cases with doubtful results). Next-generation sequencing (NGS) should be adopted either where there is limited tissue or as part of NGS tumour profiling in the context of precision oncology, acknowledging that conventional histology of PDAC may rarely harbour MSI/dMMR.

Cannulation procedure optimization for patients with duodenal papillary tumors

BACKGROUND

The goal of this study was to compare the efficacy and safety of needle-knife fistulotomy (NKF) to that of conventional cannulation methods (CCMs) when used for primary biliary access in patients with duodenal papillary tumors.

METHODS

Consecutive patients who had duodenal papillary tumors and who underwent endoscopic retrograde cholangiopancreatography (ERCP) were retrospectively enrolled. Successful cannulation rates, cannulation and procedure times, and the prevalence of adverse events were compared between the NKF and CCM groups.

RESULTS

A total of 404 patients (NKF, n = 124; CCM, n = 280) with duodenal papillary tumors were included. The primary and overall cannulation rates were 92.1% (372/404) and 96.0% (388/404), respectively. Compared to CCMs, NKF was associated with a significantly higher successful cannulation rate (99.2% versus 88.9%, P < 0.001) and significantly lower cannulation times (2.1 ± 2.0 min versus 4.7 ± 5.2 min), procedure times (8.8 ± 3.8 min versus 12.9 ± 7.6 min), and unintentional pancreatic duct cannulation rates (1.6% versus 20%), with P < 0.001 for all. Overall adverse events occurred less frequently in the NKF group (3.2% versus 10.7%, P = 0.011). Of these adverse events, post-ERCP pancreatitis (PEP) was significantly lower in the NKF group than in the CCM group (1.6% versus 6.8%, P = 0.03). Bleeding and cholangitis rarely occurred with either cannulation method (0.8% versus 2.1%, P = 0.681, and 0.8% versus 1.7%, P = 0.671, respectively).

CONCLUSION

NKF is a more effective and safer procedure than CCMs for patients with duodenal papillary tumors.

Prognostic impact of tumor budding and EMT in periampullary adenocarcinoma: a quantitative approach

The presence of invasive cell clusters known as tumor budding and the closely related epithelial mesenchymal transition (EMT) have a prognostic impact on cancer patients' overall survival. Interestingly, data quantitatively analyzing and correlating the amount of tumor buds and patient overall survival as well as the impact of expression of epithelial phenotype markers are missing. Periampullary carcinoma samples of 171 patients were immunohistochemically stained for E-Cadherin (ECad). Tumor cell clusters (TCC, defined from one to 50 cells) were manually quantified comprising tumor cell number and subcellular localization of ECad expression (membranous, cytoplasmic or mixed). Data analyses were performed using elastic net feature selection. Hereby, five distinct intervals of TCC sizes and corresponding fractions of cells with distinct ECad expression were identified. Prognostic features of the defined budding categories were entered into a subsequent Cox regression model together with standard clinicopathological parameters and, based on the model prediction, cases were categorized into "low and high budding" grades. Overall median TCC size was 16 cells (range: 2-36 cells). The median number of TCCs per tumor was 42 (range: 3-283). Elastic net feature selection identified TCCs of 6-10 and 31-35 cells as prognostically most relevant negative and positive features, respectively. Regarding ECad expression, cytoplasmic ECad expression in TCCs of 11-15 as well as of 26-30 cells revealed prognostic relevance. Combining TCC numbers and ECad expression, budding grade qualified as independent prognostic factor for patient overall survival (p<0.001) in a multivariable clinicopathologic Cox model. Applying an advanced modelling by machine learning on a cohort of periampullary cancers, we show that not the smallest TCCs (1-5 cells) but tumor cell nests containing 6-10 cells display the strongest negative prognostic relevance. Moreover, we demonstrate that larger TCCs might have a strong positive prognostic impact in periampullary adenocarcinomas, contributing to establishing an advanced grading system.

Development and external validation of a prediction model for survival in patients with resected ampullary adenocarcinoma

INTRODUCTION

Ampullary adenocarcinoma (AAC) is a rare malignancy with great morphological heterogeneity, which complicates the prediction of survival and, therefore, clinical decision-making. The aim of this study was to develop and externally validate a prediction model for survival after resection of AAC.

MATERIALS AND METHODS

An international multicenter cohort study was conducted, including patients who underwent pancreatoduodenectomy for AAC (2006-2017) from 27 centers in 10 countries spanning three continents. A derivation and validation cohort were separately collected. Predictors were selected from the derivation cohort using a LASSO Cox proportional hazards model. A nomogram was created based on shrunk coefficients. Model performance was assessed in the derivation cohort and subsequently in the validation cohort, by calibration plots and Uno's C-statistic. Four risk groups were created based on quartiles of the nomogram score.

RESULTS

Overall, 1007 patients were available for development of the model. Predictors in the final Cox model included age, resection margin, tumor differentiation, pathological T stage and N stage (8th AJCC edition). Internal cross-validation demonstrated a C-statistic of 0.75 (95% CI 0.73-0.77). External validation in a cohort of 462 patients demonstrated a C-statistic of 0.77 (95% CI 0.73-0.81). A nomogram for the prediction of 3- and 5-year survival was created. The four risk groups showed significantly different 5-year survival rates (81%, 57%, 22% and 14%, p < 0.001). Only in the very-high risk group was adjuvant chemotherapy associated with an improved overall survival.

CONCLUSION

A prediction model for survival after curative resection of AAC was developed and externally validated. The model is easily available online via www.pancreascalculator.com.

Frequency and clinicopathologic associations of DNA mismatch repair protein deficiency in ampullary carcinoma: Routine testing is indicated

BACKGROUND

The significance of DNA mismatch repair (MMR) deficiency in ampullary cancers (ACs) has not been established.

METHODS

In total, 127 ACs with invasive carcinomas measuring ≥3 mmthat had adequate tissue were analyzed immunohistochemically.

RESULTS

MMR loss was detected in 18% of ACs (higher than in colorectal cancers). Twelve tumors with MLH1-PMS2 loss were negative for BRAF V600E mutation, suggesting a Lynch syndrome association. MMR-deficient tumors (n = 23), comparedwith MMR-intact tumors (n = 104), showed a striking male predominance (male:female ratio, 4.7). Although the deficient tumors had slightly larger invasion size (2.7 vs 2.1 cm), they also had more expansile growth and less invasiveness, including less perineural invasion, and they ultimately had lower tumor (T) classification and less lymph node metastasis (30% vs 53%; P = .04). More important, patients who had MMR-deficient tumors had better clinical outcomes, with a 5-year overall survival rate of 68% versus 45% (P = .03), which was even more pronounced in those who had higher Tclassification (5-year overall survival, 69% vs 34%; P = .04). MMR deficiencyhad a statistically significant association with medullary phenotype, pushing-border invasion, and tumor-infiltrating immune cells, and it occurred more frequently in ampullary-duodenal type tumors. Programed cell death-ligand 1 (PD-L1) levels analyzed in the 22 MMR-deficient ACs revealed that all medullary carcinomas were positive. Nonmedullary MMR-deficient carcinomas expressed PD-L1 in 33% of tumors cells according to the criteria for a combined positive score ≥1, but all were negative according to the tumor proportion score≥1 method.

CONCLUSIONS

In ACs, MMR deficiency is even more frequent (18%) than in colon cancer and often has a Lynch-suggestive profile, thus routine testing is warranted. Male gender, pushing-border infiltration, ampullary-duodenal origin, medullary histology, and tumor-related inflammation have a significantly higher association with MMR deficiency. MMR-deficient tumors have less aggressive behavior. PD-L1 expression is common in medullary-phenotype ACs, thus immunotherapy should be considered at least for this group.

Approaches to Biopsy and Resection Specimens from the Ampulla

The ampulla of Vater gives rise to a versatile group of cancers of mixed/hybrid histologic phenotype. Ampullary carcinomas (ACs) are most frequently intestinal or pancreatobiliary adenocarcinomas but other subtypes, such as medullary, mucinous, or signet ring/poorly cohesive cell carcinoma, may be encountered. Ampullary cancer can also be subclassified based on immunohistochemical features, however these classification systems fail to show robust prognostic reliability. More recently, the molecular landscape of AC has been uncovered, and has been shown to have prognostic and predictive significance. In this article, the site-specific, histologic, and genetic characteristics of ampullary carcinoma and its precursor lesions are discussed.

Synchronous Periampullary Tumors in a Patient With Pancreas Divisum and Neurofibromatosis Type 1

INTRODUCTION

In this study, we describe for the first time a Neurofibromatosis type 1 patient with pancreas divisum, multiple periampullary tumors and germline pathogenic variants in NF1 and CFTR genes.

CASE REPORT

A 62-year-old female NF1 patient presented with weakness, choluria, nausea, and diffuse abdominal pain to an emergency room service. Magnetic resonance imaging revealed an abdominal mass involving the periampullary region and pancreas divisum. After surgical resection, three synchronous neoplasms were detected including two ampullary tumors (adenocarcinoma of the major ampulla and a neuroendocrine tumor of the minor ampulla) and a gastrointestinal stromal tumor (GIST). Germline multigene panel testing (MGPT) identified two pathogenic heterozygous germline variants: NF1 c.838del and CFTR c.1210-34TG[12]T[5].

CONCLUSION

This is the first report of a Neurofibromatosis type 1 patient with pancreas divisum and multiple periampullary tumors harboring pathogenic germline variants in NF1 and CFTR genes. The identification of two germline variants and a developmental anomaly in this patient may explain the unusual and more severe findings and underscores the importance of comprehensive molecular analyses in patients with complex phenotypes.

Gemcitabine-based adjuvant chemotherapy in subtypes of ampullary adenocarcinoma: international propensity score-matched cohort study

BACKGROUND

Whether patients who undergo resection of ampullary adenocarcinoma have a survival benefit from adjuvant chemotherapy is currently unknown. The aim of this study was to compare survival between patients with and without adjuvant chemotherapy after resection of ampullary adenocarcinoma in a propensity score-matched analysis.

METHODS

An international multicentre cohort study was conducted, including patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma between 2006 and 2017, in 13 centres in six countries. Propensity scores were used to match patients who received adjuvant chemotherapy with those who did not, in the entire cohort and in two subgroups (pancreatobiliary/mixed and intestinal subtypes). Survival was assessed using the Kaplan-Meier method and Cox regression analyses.

RESULTS

Overall, 1163 patients underwent pancreatoduodenectomy for ampullary adenocarcinoma. After excluding 187 patients, median survival in the remaining 976 patients was 67 (95 per cent c.i. 56 to 78) months. A total of 520 patients (53·3 per cent) received adjuvant chemotherapy. In a propensity score-matched cohort (194 patients in each group), survival was better among patients who received adjuvant chemotherapy than in those who did not (median survival not reached versus 60 months respectively; P = 0·051). A survival benefit was seen in patients with the pancreatobiliary/mixed subtype; median survival was not reached in patients receiving adjuvant chemotherapy and 32 months in the group without chemotherapy (P = 0·020). Patients with the intestinal subtype did not show any survival benefit from adjuvant chemotherapy.

CONCLUSION

Patients with resected ampullary adenocarcinoma may benefit from gemcitabine-based adjuvant chemotherapy, but this effect may be reserved for those with the pancreatobiliary and/or mixed subtype.

Very early recurrence following pancreaticoduodenectomy in patients with ampullary cancer

We aimed to identify the factors for very early recurrence (within 6 months) of ampullary cancer following curative resection and to compare the immunohistochemical expression rate of various antibodies between the 2 main histologic subtypes of ampullary adenocarcinoma.In this retrospective study, the postoperative outcomes and clinicopathologic factors for very early recurrence that occurred in 14 of 93 patients who underwent pancreaticoduodenectomy (PD) for ampullary adenocarcinoma between January 2002 and August 2014 were analyzed. Thereafter, we identified the factors associated with very early recurrence following surgery. Additionally, we compared the expression rates of CK7, CK20, MUC1, MUC2, MUC5AC, MUC6, S100P, and CDX2 between the 2 main histologic subtypes of ampullary adenocarcinoma (NCC2019-0138).The patients who underwent PD for ampullary cancer were divided into 2 groups: very early recurrence and others. Compared with the other patients, the 14 patients (32.6%) who developed very early recurrence had shorter median disease-free survival (4.2 vs 49.7 months, P = .001) and overall survival (18.2 vs 113.7 months, P < .001). Large tumor, lymph node metastasis, and pancreatobiliary type were independently associated with very early recurrence of ampullary cancer following PD.Large tumor, lymph node metastasis, and pancreatobiliary type were the independent risk factors for very early recurrence of ampullary cancer following curative resection. Therefore, ampullary cancer patients with these factors should be considered to receive aggressive adjuvant treatment and frequent post-operative follow-up.

Laterally Spreading Adenocarcinoma Involving the Lower Bile Duct and Duodenum Expressing Heterogeneous Immunohistochemical Phenotypes

A 70-year-old man was admitted to our hospital due to elevated levels of hepatobiliary and pancreatic enzymes. Computed tomography showed contrast-enhanced mucosal hypertrophy from the duodenal papilla to the distal bile duct. Endoscopic examinations revealed a laterally spreading granular tumor and ampullary swelling. After surgical resection, an examination revealed well-differentiated adenocarcinoma of the ampulla with tubular adenoma spreading from the distal common bile duct to the second part of the duodenum showing both bile duct and duodenal phenotypes. To our knowledge, this is the first case of a tumor spreading from the bile duct to the duodenum that exhibited multiple phenotypes.

Apparent diffusion coefficient-based histogram analysis differentiates histological subtypes of periampullary adenocarcinoma

BACKGROUND

For periampullary adenocarcinoma, the histological subtype is a better prognostic predictor than the site of tumor origin. Intestinal-type periampullary adenocarcinoma (IPAC) is reported to have a better prognosis than the pan-creatobiliary-type periampullary adenocarcinoma (PPAC). However, the classification of histological subtypes is difficult to determine before surgery. Apparent diffusion coefficient (ADC) histogram analysis is a noninvasive, non-enhanced method with high reproducibility that could help differentiate the two subtypes.

AIM

To investigate whether volumetric ADC histogram analysis is helpful for distinguishing IPAC from PPAC.

METHODS

Between January 2015 and October 2018, 476 consecutive patients who were suspected of having a periampullary tumor and underwent magnetic resonance imaging (MRI) were reviewed in this retrospective study. Only patients who underwent MRI at 3.0 T with different diffusion-weighted images (b-values = 800 and 1000 s/mm²) and who were confirmed with a periampullary adenocarcinoma were further analyzed. Then, the mean, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values and ADC_min, ADC_max, kurtosis, skewness, and entropy were obtained from the volumetric histogram analysis. Comparisons were made by an independent Student's t-test or Mann-Whitney U test. Multiple-class receiver operating characteristic curve analysis was performed to determine and compare the diagnostic value of each significant parameter.

RESULTS

In total, 40 patients with histopathologically confirmed IPAC (n = 17) or PPAC (n = 23) were enrolled. The mean, 5th, 25th, 50th, 75th, 90th, and 95th percentiles and ADC_max derived from ADC₁₀₀₀ were significantly lower in the PPAC group than in the IPAC group (P < 0.05). However, values derived from ADC₈₀₀ showed no significant difference between the two groups. The 75th percentile of ADC₁₀₀₀ values achieved the highest area under the curve (AUC) for differentiating IPAC from PPAC (AUC = 0.781; sensitivity, 91%; specificity, 59%; cut-off value, 1.50 × 10^-3 mm²/s).

CONCLUSION

Volumetric ADC histogram analysis at a b-value of 1000 s/mm² might be helpful for differentiating the histological subtypes of periampullary adenocarcinoma before surgery.

Poorly Cohesive (Signet Ring Cell) Carcinoma of the Ampulla of Vater

In the ampulla of Vater, carcinomas with "diffuse-infiltrative"/"signet ring cell" morphology, designated as "poorly cohesive carcinoma" (PCC) in the WHO classification, are very rare and poorly characterized. Nine cases with a classical PCC morphology constituting >50% of the tumor were identified. Mean age was 64.8 years (vs 64.6 in ampullary carcinomas [ACs]) and 6 were males, 3 females. The mean invasive tumor size was 2.5 cm (vs 1.9 in ACs). Other morphologic patterns displayed included cord-like infiltration (n=2), plasmacytoid cells (n=2), and microglandular component (n=4), including goblet cell adenocarcinoma-like foci. None of the cases were associated with dysplasia. By immunohistochemistry, the carcinomas did not show intestinal differentiation (CDX2 0/9, CK20 1/9, MUC2 3/9), MUC1 was positive in 4/9, MUC5AC was positive in 7/8. E-cadherin loss was noted in 4/9. All cases were advanced stage (6/9-pT3, 3/9-pT4) (vs 43% in ACs). Lymph node metastases were identified in 44% (vs 45% in AC). Six patients (67%) died of disease at a median of 25 months, 3 were alive at 13, 15, and 60 months. Overall median survival was significantly worse than that of intestinal-type ACs (26 vs 122 months, P = .006) and trended toward worse than pancreatobiliary type (26 vs 42 months, P = .1). In conclusion, PCCs constitute 2.45% of all ACs. These present as advanced tumors and express upper-gastrointestinal immunoprofile with frequent MUC5AC labeling, which may be helpful in identifying subtle infiltration in the surface mucosa since MUC5AC is not expressed in the ampullary mucosa. Patients have poor prognosis.

Whipple Grossing in the Era of New Staging: Should We Standardize?

Whipple procedure, also known as pancreatoduodenectomy, is the most common surgery for the removal of tumors of the head of the pancreas, ampulla, distal common bile duct, or periampullary duodenum. It is also one of the most challenging resection specimens grossed by surgical pathologists. A thorough and consistent evaluation of the gross surgical specimen is the most critical first step for accurate diagnosis, determination of tumor origin, staging, and evaluation of margin status. However, there has been no standard grossing protocol for Whipple specimens, which has led to inaccurate diagnoses, staging, and inconsistent reporting. This issue has become even more challenging in the era of the size-based tumor staging systems recommended by the new 8th Edition of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual. Moreover, new concerns have been raised regarding how to best evaluate margin status and lymph nodes. Studies have shown that different Whipple grossing methods can significantly impact margin assessment and lymph node yield and thus affect R0/R1 status and clinical stage. Other important issues under debate include nomenclature, definitions of margin (versus surface), and R1 status. Consistent Whipple grossing and standardization of reporting will provide better communication and more accurate diagnosis and staging, as well as prognostic prediction.