Subgrading of G2 Pancreatic Neuroendocrine Tumors as 2A (Ki67 3% to < 10%) Versus 2B (10% to ≤ 20%) Identifies Behaviorally Distinct Subsets in Keeping with the Evolving Management Protocols.

BACKGROUND: Grade 1/2 PanNETs are mostly managed similarly, typically without any adjunct treatment with the belief that their overall metastasis rate is low. In oncology literature, Ki67-index of 10% is increasingly being used as the cutoff in stratifying patients to different protocols, although there are no systematic pathology-based studies supporting this approach. METHODS: Ki67-index was correlated with clinicopathologic parameters in 190 resected PanNETs. A validation cohort (n = 145) was separately analyzed. RESULTS: In initial cohort, maximally selected rank statistics method revealed 12% to be the discriminatory cutoff (close to 10% rule of thumb). G2b cases had liver/distant metastasis rate of almost threefold higher than that of G2a and showed significantly higher frequency of all histopathologic signs of aggressiveness (tumor size, perineural/vascular invasion, infiltrative growth pattern, lymph node metastasis). In validation cohort, these figures were as striking. When all cases were analyzed together, compared with G1, the G2b category had nine times higher liver/distant metastasis rate (6.1 vs. 58.5%; p < 0.001) and three times higher lymph node metastasis rate (20.5 vs. 65.1%; p < 0.001). CONCLUSIONS: G2b PanNETs act very similar to G3, supporting management protocols that regard them as potential therapy candidates. Concerning local management, metastatic behavior in G2b cases indicate they may not be as amenable for conservative approaches, such as watchful waiting or enucleation. This substaging should be considered into diagnostic guidelines, and clinical trials need to be devised to determine the more appropriate management protocols for G2b (10% to ≤ 20%) group, which shows liver/distant metastasis in more than half of the cases, which at minimum warrants closer follow-up.

Infiltration pattern predicts metastasis and progression better than the T-stage and grade in pancreatic neuroendocrine tumors: a proposal for a novel infiltration-based morphologic grading.

The advancing edge profile is a powerful determinant of tumor behavior in many organs. In this study, a grading system assessing the tumor-host interface was developed and tested in 181 pancreatic neuroendocrine tumors (PanNETs), 63 of which were <=2 cm. Three tumor slides representative of the spectrum (least, medium, and most) of invasiveness at the advancing edge of the tumor were selected, and then each slide was scored as follows. Well-demarcated/encapsulated, 1 point; Mildly irregular borders and/or minimal infiltration into adjacent tissue, 2 points; Infiltrative edges with several clusters beyond the main tumor but still relatively close, and/or satellite demarcated nodules, 3 points; No demarcation, several cellular clusters away from the tumor, 4 points; Exuberantly infiltrative pattern, scirrhous growth, dissecting the normal parenchymal elements, 5 points. The sum of the rankings on the three slides was obtained. Cases with scores of 3-6 were defined as "non/minimally infiltrative" (NI; n = 77), 7-9 as "moderately infiltrative" (MI; n = 68), and 10-15 as "highly infiltrative" (HI; n = 36). In addition to showing a statistically significant correlation with all the established signs of aggressiveness (grade, size, T-stage), this grading system was found to be the most significant predictor of adverse outcomes (metastasis, progression, and death) on multivariate analysis, more strongly than T-stage, while Ki-67 index did not stand the multivariate test. As importantly, cases <=2 cm were also stratified by this grading system rendering it applicable also to this group that is currently placed in "watchful waiting" protocols. In conclusion, the proposed grading system has a strong, independent prognostic value and therefore should be considered for integration into routine pathology practice after being evaluated in validation studies with larger series.

The conversion of RAS status in metastatic colorectal cancer patients after first-line biological agent treatment.

AIM: The aim was to investigate the RAS discordance between initial and recurrent metastasectomy specimens in metastatic colorectal cancer (mCRC) patients treated with chemotherapy (CT) plus biological agents in a first-line setting. METHODS: Patients who had been treated with CT plus bevacizumab or cetuximab or panitumumab followed by R0 resection for potentially resectable colorectal cancer liver metastases were scanned. Among these, patients who developed resectable new metastases after a disease-free interval longer than 6 months were included in the study. We compared the RAS mutation status between the first biopsy and the second metastasectomy specimen. RESULTS: A total of 82 mCRC patients treated with CT plus biological agents in a first-line setting were included in the study. The first biopsy assessment showed wild-type RAS tumours in 39 (47.6%) patients and mutant RAS tumours in 43 (52.4%) patients. The mean time for new operable liver metastasis after R0 resection was 15.5 months. In the second metastasectomy specimens, the numbers of wild-type and mutant RAS tumours were 30 (36.6%) and 52 (63.4%), respectively. The comparison with the first biopsy specimens showed RAS status conversions in 17 (20.7%) patients. Univariate comparison between patients with and without RAS status conversion revealed that grade, pathological T stage, wild-type RAS tumour and longer biological agent use time in the first-line treatment were significant factors for RAS conversion. CONCLUSION: Our results suggest that re-biopsy is needed for an optimal second-line treatment decision in mCRC patients regardless of backbone biological agent, especially in patients with wild-type RAS mCRC.

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.

The potential prognostic role of peritumoral eosinophils within whole tumor-associated inflammatory cells and stromal histological characteristics in colorectal cancer.

We aimed to determine the prognostic role of whole tumor-associated inflammatory cells, especially eosinophils, and stromal histological characteristics in relation to other prognostic parameters in patients with colorectal carcinoma (CRC). A total of 122 patients who underwent an operation for CRC were included in this retrospective study. Conventional (tumor grade, TNM stage and venous invasion [VI]) and other histopathological (intratumoral/peritumoral budding [ITB/PTB], desmoplasia) tumor parameters were recorded and classified by density, as were the tumor-associated inflammatory parameters (intratumoral/peritumoral lymphocytes [ITL/PTL], eosinophils [IE/PTE], overall inflammation [ITI/PTI], Crohn-like inflammation [CLI]). Cancer-specific survival data were analyzed with respect to all tumor parameters. High ITB and PTB were significantly correlated with a higher rate of pT4, VI and desmoplasia (p < 0.05). An association of moderate ITL and extensive PTL with lesser likelihood of VI and metastasis; an association of extensive CLI with a significantly lower rate of metastasis and TNM stage IV; and minimal PTE with a significantly higher rate of pT4 stage, metastasis and ITB were detected (p < 0.05 for each). Our findings revealed that low score tumoral budding and an increase in tumor-related inflammation were associated with lesser likelihood of poor prognostic tumor parameters. Nonetheless, given the association of an increase in PTE with lesser likelihood of ITB, pT4, metastasis, and with non-significantly for better survival rates, our findings emphasize the potential role of peritumoral eosinophils as an additional prognostic parameter in CRC.

Non-ampullary-duodenal carcinomas: clinicopathologic analysis of 47 cases and comparison with ampullary and pancreatic adenocarcinomas.

Literature on non-ampullary-duodenal carcinomas is limited. We analyzed 47 resected non-ampullary-duodenal carcinomas. Histologically, 78% were tubular-type adenocarcinomas mostly gastro-pancreatobiliary type and only 19% pure intestinal. Immunohistochemistry (n=38) revealed commonness of 'gastro-pancreatobiliary markers' (CK7 55, MUC1 50, MUC5AC 50, and MUC6 34%), whereas 'intestinal markers' were relatively less common (MUC2 36, CK20 42, and CDX2 44%). Squamous and mucinous differentiation were rare (in five each); previously, unrecognized adenocarcinoma patterns were noted (three microcystic/vacuolated, two cribriform, one of comedo-like, oncocytic papillary, and goblet-cell-carcinoid-like). An adenoma component common in ampullary-duodenal cancers was noted in only about a third. Most had plaque-like or ulcerating growth. Mismatch repair protein alterations were detected in 13% (all with plaque-like growth and pushing-border infiltration). When compared with ampullary (n=355) and pancreatic ductal (n=227) carcinomas, non-ampullary-duodenal carcinomas had intermediary pathologic features with mean invasive size of 2.9 cm (vs 1.9, and 3.3) and 59% nodal metastasis (vs 45, and 77%). Its survival (3-, 5-year rates of 57 and 57%) was similar to that of ampullary-duodenal carcinomas (59 and 52%; P=0.78), but was significantly better than the ampullary ductal (41 and 29%, P<0.001) and pancreatic (28 and 18%, P<0.001) carcinomas. In conclusion, non-ampullary-duodenal carcinomas are more histologically heterogeneous than previously appreciated. Their morphologic versatility (commonly showing gastro-pancreatobiliary lineage and hitherto unrecognized patterns), frequent plaque-like growth minus an adenoma component, and frequent expression of gastro-pancreatobiliary markers suggest that many non-ampullary-duodenal carcinomas may arise from Brunner glands or gastric metaplasia or heterotopic pancreatobiliary epithelium. The clinical behavior of non-ampullary-duodenal carcinoma is closer to that of ampullary-duodenal subset of ampullary carcinomas, but is significantly better than that of ampullary ductal and pancreatic cancers. The frequency of mismatch repair protein alterations suggest that routine testing should be considered, especially in the non-ampullary-duodenal carcinomas with plaque-like growth and pushing-border infiltration.

Pancreatic Ductal Adenocarcinoma is Spread to the Peripancreatic Soft Tissue in the Majority of Resected Cases, Rendering the AJCC T-Stage Protocol (7th Edition) Inapplicable and Insignificant: A Size-Based Staging System (pT1: ≤2, pT2: >2-≤4, pT3: >4 cm) is More Valid and Clinically Relevant.

BACKGROUND: Most studies have failed to identify any prognostic value of the current T-stage protocol for pancreatic ductal adenocarcinoma (PDAC) by the American Joint Committee on Cancer and the Union for International Cancer Control unless some grouping was performed. METHODS: To document the parameters included in this T-stage protocol, 223 consecutive pancreatoduodenectomy specimens with PDAC were processed by a uniform grossing protocol. RESULTS: Peripancreatic soft tissue (PST) involvement, the main pT3 parameter, was found to be inapplicable and irreproducible due to lack of a true capsule in the pancreas and variability in the amount and distribution of adipose tissue. Furthermore, 91 % of the cases showed carcinoma in the adipose tissue, presumably representing the PST, and thus were classified as pT3. An additional 4.5 % were qualified as pT3 due to extension into adjacent sites. The T-stage defined as such was not found to have any correlation with survival (p = 0.4). A revised T-stage protocol was devised that defined pT1 as 2 cm or smaller, pT2 as >2-4 cm, and pT3 as larger than 4 cm. This revised protocol was tested in 757 consecutive PDACs. The median and 3-year survival rates of this size-based protocol were 26, 18, 13 months, and 40 %, 26 %, 20 %, respectively (p < 0.0001). The association between higher T-stage and shorter survival persisted in N0 cases and in multivariate modeling. Analysis of the Surveillance, Epidemiology, and End Results database also confirmed the survival differences (p < 0.0001). CONCLUSIONS: This study showed that resected PDACs are already spread to various surfaces of the pancreas, leaving only about 4 % of PDACs to truly qualify as pT1/T2, and that the current T-stage protocol does not have any prognostic correlation. In contrast, as shown previously in many studies, size is an important prognosticator, and a size-based T-stage protocol is more applicable and has prognostic value in PDAC.

Performance and prognostic utility of the 92-gene assay in the molecular subclassification of ampullary adenocarcinoma.

BACKGROUND: Ampullary adenocarcinoma is a rare gastrointestinal cancer associated with diverse outcomes due to clinical and pathological heterogeneity. Standardized methods to better prognosticate and inform therapeutic selection for ampullary adenocarcinoma are needed. This study explored the novel use and potential prognostic utility of a 92-gene cancer classifier in ampullary adenocarcinomas. METHODS: In this prospectively-defined, blinded study of ampullary adenocarcinoma [N =54; stage T3 or higher (57 %); Grade III (44 %); Node positive (55 %)], the performance of a 92-gene classifier was examined to predict the ampullary subtype that was derived from histomorphological examination of resected ampullary samples. Outcome data for relapse-free survival (RFS) and overall survival (OS) were plotted to compare the prognostic utility of histological subtyping, histomolecular phenotyping, and the 92-gene classifier. Multivariate analysis was used to determine clinicopathological variables that were independently associated with overall survival. RESULTS: The 92-gene classifier demonstrated sensitivities and specificities of 85 % [95 % CI, 66-94] and 68 % [95 % CI, 48-84] and 64 % [95 % CI, 46-79] and 88 % [95 % CI, 70-98] for the pancreaticobiliary and intestinal histological subtypes, respectively. For the 92-gene classifier, improved outcomes were observed for the intestine versus the pancreaticobiliary prediction (median OS 108.1 v 36.4 months; HR, 2.17; 95 % CI, 0.98 to 4.79; P = 0.05). Similar results were seen for ampullary adenocarcinoma stratification by histological subtype (P = 0.04) and histomolecular phenotype (P = 0.02). Within poorly differentiated ampullary adenocarcinomas only the 92-gene classifier demonstrated statistically significant differences in RFS and OS (P < 0.05). CONCLUSIONS: Prognostic stratification of ampullary adenocarcinoma was similar for the 92-gene classifier, histological subtype, and histomolecular phenotype. The 92-gene classifier provides an unbiased standardized molecular-based approach to stratify ampullary tumors.

Calculation of the Ki67 index in pancreatic neuroendocrine tumors: a comparative analysis of four counting methodologies.

Ki67 index is now an essential part of classification of pancreatic neuroendocrine tumors. However, its adaptation into daily practice has been fraught with challenges related to counting methodology. In this study, three reviewers used four counting methodologies to calculate Ki67 index in 68 well-differentiated pancreatic neuroendocrine tumors: (1) 'eye-ball' estimation, which has been advocated as reliable and is widely used; (2) automated counting by image analyzer; (3) manual eye-counting (eye under a microscope without a grid); and (4) manual count of camera-captured/printed image. Pearson's correlation (R) was used to measure pair-wise correlation among three reviewers using all four methodologies. Average level of agreement was calculated using mean of R values. The results showed that: (1) 'eye-balling' was least expensive and fastest (average time <1 min) but had poor reliability and reproducibility. (2) Automated count was the most expensive and least practical with major impact on turnaround time (limited by machine and personnel accessibility), and, more importantly, had inaccuracies in overcounting unwanted material. (3) Manual eye count had no additional cost, averaged 6 min, but proved impractical and poorly reproducible. (4) Camera-captured/printed image was most reliable, had highest reproducibility, but took longer than 'eye-balling'. In conclusion, based on its comparatively low cost/benefit ratio and reproducibility, camera-captured/printed image appears to be the most practical for calculating Ki67 index. Although automated counting is generally advertised as the gold standard for index calculation, in this study it was not as accurate or cost-effective as camera-captured/printed image and was highly operator-dependent. 'Eye-balling' produces highly inaccurate and unreliable results, and is not recommended for routine use.

Intraductal tubulopapillary neoplasms of the bile ducts: clinicopathologic, immunohistochemical, and molecular analysis of 20 cases.

Intraductal tubulopapillary neoplasm is a well-established entity in the pancreas. A similar, if not identical, tumor occurs also in the biliary tract. We conducted a multicenter study of 20 such lesions, focusing on their clinicopathologic characteristics and molecular profile. Biliary intraductal tubulopapillary neoplasms were seen in patients in their 60s (mean 62 years). The tumors were intrahepatic 70%, extrahepatic 10%, and perihilar 20%; mean tumor size was 6.9 cm. Histologically, all intraductal tubulopapillary neoplasms showed, in addition to their typical tubular pattern, solid areas (70%) or abortive papillae (50%). Necrosis was common (85%), predominantly focal (40%), and with 'comedocarcinoma-like pattern' in 40%. Immunohistochemically, these neoplasms were characterized by the expression of MUC1 (80%) and MUC6 (30%) and by the absence of MUC2 and MUC5AC. Associated invasive carcinomas were present in 16 (80%), mainly conventional tubular adenocarcinoma (50%). The molecular alterations observed included CDKN2A/p16 (intraductal components 44%, invasive 33%) and TP53 (intraductal components 17%, invasive 9%). Mutations in KRAS (intraductal 6%, invasive 0%), PIK3CA (intraductal 6%, invasive 0%), and loss of SMAD4/DPC4 (intraductal 7%, invasive 0%) were rare. No alterations/mutations were identified in IDH1/2, BRAF, GNAS, EGFR, HER2, and ß-catenin. Follow-up information was available for 17 patients (85%) with mean follow-up 44 months. Overall combined survival rates showed favorable prognosis: 1 year 100%, 3 years 90%, and 5 years 90%. In conclusion, despite the relatively high incidence of invasive carcinoma (80%), available follow-up suggests that biliary intraductal tubulopapillary neoplasms have an indolent behavior. Molecular analyses highlight the low prevalence of alterations of common oncogenic signaling pathways in intraductal tubulopapillary neoplasm. Further studies using whole-exome sequencing are required to discover yet unknown molecular changes and to understand the carcinogenesis of intraductal tubulopapillary neoplasms.

Substaging of Lymph Node Status in Resected Pancreatic Ductal Adenocarcinoma Has Strong Prognostic Correlations: Proposal for a Revised N Classification for TNM Staging.

BACKGROUND: The current tumor-node-metastasis staging system for the pancreas does not incorporate the number of lymph nodes (LNs) with metastasis. METHODS: Among 1649 pancreaticoduodenectomies, 227 stringently defined pancreatic ductal adenocarcinomas (PDACs) that had undergone a specific approach of LN harvesting were analyzed for the prognostic value of LN substaging protocols used for other gastrointestinal (GI) organs. RESULTS: The median number of LNs harvested was 18, and the median number of LNs with metastasis was 3. Lymph node metastasis was detected in 175 cases (77 %). The number of LNs involved correlated significantly with clinical outcome. When cases were substaged with the protocol already in use for the upper GI organs (N0: no metastasis, N1: metastasis to 1-2 LNs; N2: metastasis to ≥3 LNs), the median overall survival times were 35, 21, and 18 months, and the respective 3-year survival rates were 46, 34, and 20 % (p = 0.004). Analysis of the Surveillance, Epidemiology and End Results (SEER) database also confirmed the survival differences between these substages (median overall survival times of 23, 15, and 14 months and respective 3-year survival rates of 37, 22, and 18 %; p < 0.0001). The substaging protocol for the lower GI organs (N0: no metastasis; N1: metastasis to 1-3 LNs; N2: metastasis to ≥4 LNs) also was significant, with median overall survival times of 35, 21, 18 months and respective 3-year survival rates of 46, 26, and 23 %; p = 0.009). The association between higher N stage and shorter survival persisted with multivariate modeling for both protocols, although the prognostic value of the upper GI protocol appeared to be slightly stronger according to the Akaike Information Criterion method. CONCLUSION: In conclusion, with proper LN harvesting, the LN metastasis rate in PDACs is very high (77 %). Substaging of LN metastasis has significant prognostic value and needs to be considered in the N staging of PDACs. The protocol already in use for other upper GI tract organs, which currently also is proven significant for ampulla, would be preferable, although the lower GI tract protocol also is applicable.

Substaging Nodal Status in Ampullary Carcinomas has Significant Prognostic Value: Proposed Revised Staging Based on an Analysis of 313 Well-Characterized Cases.

BACKGROUND: Current nodal staging (N-staging) of ampullary carcinoma in the TNM staging system distinguishes between node-negative (N0) and node-positive (N1) disease but does not consider the metastatic lymph node (LN) number. METHODS: Overall, 313 patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma were categorized as N0, N1 (1-2 metastatic LNs), or N2 (≥3 metastatic LNs), as proposed by Kang et al. Clinicopathological features and overall survival (OS) of the three groups were compared. RESULTS: The median number of LNs examined was 11, and LN metastasis was present in 142 cases (45 %). When LN-positive cases were re-classified according to the proposed staging system, 82 were N1 (26 %) and 60 were N2 (19 %). There was a significant correlation between proposed N-stage and lymphovascular invasion, perineural invasion, increased tumor size (each p < 0.001), and surgical margin positivity (p = 0.001). The median OS in LN-negative cases was significantly longer than that in LN-positive cases (107.5 vs. 32 months; p < 0.001). Patients with N1 and N2 disease had median survivals of 40 and 24.5 months, respectively (p < 0.0001). In addition, 1-, 3-, and 5-year survivals were 88, 76, 62 %, respectively, for N0; 90, 55, 31.5 %, respectively, for N1; and 68, 34, 30 %, respectively for N2 (p < 0.001). Even with multivariate modeling, the association between higher proposed N stage and shorter survival persisted (hazard ratio 1.6 for N1 and 1.9 for N2; p = 0.018). CONCLUSIONS: Classification of nodal status in ampullary carcinomas based on the number of metastatic LNs has a significant prognostic value. A revised N-staging classification system should be incorporated into the TNM staging of ampullary cancers.

Performance of CT in the locoregional staging of colon cancer: detailed radiology-pathology correlation with special emphasis on tumor deposits, extramural venous invasion and T staging.

PURPOSE: To investigate the performance of computed tomography (CT) in the local staging of colon cancer in different segments, with emphasis on parameters that have been found to be significant for rectal cancer, namely, extramural venous invasion (EMVI) and tumor deposits (TDs). METHODS: CT and pathology data from 137 patients were independently reviewed by radiology and pathology teams. The performance of CT in categorizing a given patient into good, versus poor prognostic groups was assessed for each segment, as well as the presence of lymph nodes (LNs), TDs and EMVIs. Discordant cases were re-evaluated to determine potential sources of error. Elastic stain was applied for EMVI discordance. RESULTS: The T staging accuracy was 80.2%. For T stage stratification, CT performed slightly better in the left colon, and the lowest accuracy was in the transverse colon. Under-staging was more common (in 12.4%), and most of the mis-staged cases were in sigmoid colon. According to the first comprehensive correlative analysis, the sensitivity, specificity, and accuracy of CT for detecting TDs were found to be 57.9%, 92.4%, 87.6%, respectively. These figures were 44.7%, 72.7%, and 63.5% for LN, and 58.5%, 82.1% and 73% for EMVI. The detection rate was better for multifocal EMVI. The detection rate was also comparable (although substantially underestimated) for LNs, with the half of the LNs missed by CT being < 5 mm. Four patients that were classified as TD by CT, disclosed to be LNs by pathology. Correlative analysis led to refinement of the pathology criteria, with subsequent modifications of the initial reports in 13 (9.5%) patients. CONCLUSION: Overall, CT performed well in the evaluation of colon cancer, as did TD and EMVI. It is advisable to include these parameters in CT-based staging. Radiologists should be aware of the pitfalls that occur more commonly in different segments.

Tubulocystic Carcinoma of Bile Ducts: A Distinct Type of Cholangiocarcinoma Associated With Adenofibroma-type Lesions.

A type of cholangiocarcinoma (CCA) characterized by peculiar histologic patterns and underlying adenofibromatous lesions has been reported in the literature mostly as individual case reports. This study aims to further clarify the defining characteristics of this spectrum of lesions. Clinicopathologic analysis of 8 biliary tumors with tubulocystic architecture arising in the background of adenofibroma-type lesions was performed. Three of these were also investigated with next-generation sequencing with a 174 genes panel. The patients were 5 males and 3 females, with a mean age of 64.6. All tumors were intrahepatic except for one perihilar that protruded into soft tissues. The mean size was 4.4 cm. At histology, all cases showed a peculiar and cytologically bland tubulocystic pattern that closely resembled tubulocystic-type kidney cancers, including back-to-back microcystic units that formed relatively demarcated nodules, and occurring in the background of adenofibromatous lesions. One case showed perineural invasion by otherwise deceptively benign-appearing microcystic structures, one had areas transitioning to intraductal tubulopapillary neoplasm, and 3 cases harbored more conventional small-duct CCA foci. In those 3 cases, both the tubulocystic and conventional CCA components were investigated by next-generation sequencing separately, and they shared the molecular alterations, including recurrent mutations in chromatin remodeling genes, such as ARID1A, BAP1, and PBRM1, and the actionable FGFR2-MCU fusion gene. In the limited follow-up, all but one were alive and free of disease after surgical resection. In conclusion, we described a distinct entity of CCA with specific histo-molecular features, for which we propose the designation of tubulocystic carcinoma of bile ducts.

Adenomyomas of the Gallbladder: An Analysis of Frequency, Clinicopathologic Associations, and Relationship to Carcinoma of a Malformative Lesion.

CONTEXT.­: The nature and associations of gallbladder (GB) "adenomyoma" (AM) remain controversial. Some studies have attributed up to 26% of GB carcinoma to AMs. OBJECTIVE.­: To examine the true frequency, clinicopathologic characteristics, and neoplastic changes in GB AM. DESIGN.­: Cholecystectomy cohorts analyzed were 1953 consecutive cases, prospectively with specific attention to AM; 2347 consecutive archival cases; 203 totally embedded GBs; 207 GBs with carcinoma; and archival search of institutions for all cases diagnosed as AM. RESULTS.­: Frequency of AM was 9.3% (19 of 203) in totally submitted cases but 3.3% (77 of 2347) in routinely sampled archival tissue. A total of 283 AMs were identified, with a female to male ratio = 1.9 (177:94) and mean size = 1.3 cm (range, 0.3-5.9). Most (96%, 203 of 210) were fundic, with formed nodular trabeculated submucosal thickening, and were difficult to appreciate from the mucosal surface. Four of 257 were multifocal (1.6%), and 3 of 257 (1.2%) were extensive ("adenomyomatosis"). Dilated glands (up to 14 mm), often radially converging to a point in the mucosa, were typical. Muscle was often minimal, confined to the upper segment. Nine of 225 (4%) revealed features of a duplication. No specific associations with inflammation, cholesterolosis, intestinal metaplasia, or thickening of the uninvolved GB wall were identified. Neoplastic change arising in AM was seen in 9.9% (28 of 283). Sixteen of 283 (5.6%) had mural intracholecystic neoplasm; 7 of 283 (2.5%) had flat-type high-grade dysplasia/carcinoma in situ. Thirteen of 283 cases had both AM and invasive carcinoma (4.6%), but in only 5 of 283 (1.8%), carcinoma arose from AM (invasion was confined to AM, and dysplasia was predominantly in AM). CONCLUSIONS.­: AMs have all the features of a malformative developmental lesion, and may not show a significant muscle component (ie, the name "adeno-myoma" is partly a misnomer). While most are innocuous, some pathologies may arise in AMs, including intracholecystic neoplasms, flat-type high-grade dysplasia or carcinoma in situ, and invasive carcinoma (1.8%, 5 of 283). It is recommended that gross examination of GBs include serial slicing of the fundus for AM detection and total submission if one is found.

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 ≤1 cm IAPNs). 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). 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).

Pronecrotic mixed lineage kinase domain-like protein expression is a prognostic biomarker in patients with early-stage resected pancreatic adenocarcinoma.

BACKGROUND: Mixed lineage kinase domain-like protein (MLKL) is a necrosome component mediating programmed necrosis that may be an important determinant of cancer cell death. The goal of the current study was to evaluate the prognostic value of MLKL expression in patients with pancreatic adenocarcinoma (PAC). METHODS: Tissue from 80 patients was collected from a prospectively maintained database of patients with PAC who underwent pancreaticoduodenectomy between January 2000 and October 2008. Immunohistochemistry analysis was performed and scored using an established scoring system. Kaplan-Meier survival curves were generated for recurrence-free survival (RFS) and overall survival (OS) for all patients and for patients receiving adjuvant chemotherapy. MLKL scores were correlated with RFS and OS using univariate and multivariate Cox regression analyses incorporating clinically relevant covariates. RESULTS: The median age of the patients was 63 years and 53% were men. Low MLKL expression was associated with decreased OS (6 months vs 17 months; P = .006). In the subset of 59 patients who received adjuvant chemotherapy, low MLKL expression was associated with decreased RFS (5 months vs 15 months; P = .006) and decreased OS (6 months vs 19 months; P < .0001). On multivariate analysis, low MLKL expression was associated with poor OS in all patients (hazards ratio, 4.6 [95% confidence interval, 1.6-13.8]; P = .006) and in patients receiving adjuvant chemotherapy (hazards ratio, 8.1 [95% confidence interval, 2.2-29.2]; P = .002). CONCLUSIONS: Low expression of MLKL is associated with decreased OS in patients with resected PAC and decreased RFS and OS in the subset of patients with resected PAC who receive adjuvant chemotherapy. The use of this biomarker in patients with PAC may provide important prognostic information.

KRAS mutant allele-specific imbalance is associated with worse prognosis in pancreatic cancer and progression to undifferentiated carcinoma of the pancreas.

KRAS codon 12 mutations are present in about 90% of ductal adenocarcinomas and in undifferentiated carcinomas of the pancreas. The role of KRAS copy number changes and resulting KRAS mutant allele-specific imbalance (MASI) in ductal adenocarcinoma (n=94), and its progression into undifferentiated carcinoma of the pancreas (n=25) was studied by direct sequencing and KRAS fluorescence in situ hybridization (FISH). Semi-quantitative evaluation of sequencing electropherograms showed KRAS MASI (ie, mutant allele peak higher than or equal to the wild-type allele peak) in 22 (18.4%) cases. KRAS FISH (performed on 45 cases) revealed a trend for more frequent KRAS amplification among cases with KRAS MASI (7/20, 35% vs 3/25, 12%, P=0.08). KRAS amplification by FISH was seen only in undifferentiated carcinomas (10/24, 42% vs 0/21 pancreatic ductal adenocarcinoma, 0%, P=0.0007). In 6 of 11 cases with both undifferentiated and well-differentiated components, transition to undifferentiated carcinoma was associated with an increase in KRAS copy number, due to amplification and/or chromosome 12 hyperploidy. Pancreatic carcinomas with KRAS MASI (compared to those without MASI) were predominantly undifferentiated (16/22, 73% vs 9/97, 9%, P<0.001), more likely to present at clinical stage IV (5/22, 23% vs 7/97, 7%, P=0.009), and were associated with shorter overall survival (9 months, 95% confidence interval, 5-13, vs 22 months, 95% confidence interval, 17-27; P=0.015) and shorter disease-free survival (5 months, 95% confidence interval, 2-8 vs 13 months, 95% confidence interval, 10-16; P=0.02). Our findings suggest that in a subset of ductal adenocarcinomas, KRAS MASI correlates with the progression to undifferentiated carcinoma of the pancreas.

Effects of Whey Protein, Omega-3 Fatty Acid and Roux-En-Y Gastric Bypass on Body Weight, Biochemical Parameters and Organ Functions in an Obese Rat Model: Experimental Research.

PURPOSE: Extreme obesity (EO) is one of the biggest public health problems in the world and has grown considerably over the years. The aim of the study is to examine the effect of Roux-en-Y gastric bypass (RYGB), whey protein (WP), and omega-3 polyunsaturated fatty acid (PUFA) supplementation applied to EO rats on weight loss, histopathological changes in internal organs and biochemical alterations. MATERIALS AND METHODS: Wistar albino female rats (n = 28) were used in the study and randomly divided into four groups. All rats were made obese by adding high fructose corn syrup (HFCS) to their drinking water. After the EO, WP and omega-3 PUFA supplementation was given and RYGB process was applied. At the end of the study, glucose, total cholesterol, HDL, VLDL, AST, ALT and uric acid changes and liver, kidney and pancreatic tissues were evaluated histopathologically. RESULTS: WP and omega-3 PUFA supplementation decreased body weight (p > 0.05). Omega-3 PUFA and RYGB caused a decrease in total cholesterol (p < 0.05), WP decreased HDL (p < 0.05), WP and omega-3 PUFA caused an increase in ALT (p < 0.05). WP has been shown to have greater curative effects in rat liver and kidney tissues. It has been determined that RYGB causes necrosis in the liver and HFCS causes inflammation in the kidney. CONCLUSION: In the study; the positive effects of WP, omega-3 PUFA and bariatric surgery on obesity and dyslipidemia have been demonstrated. With this result, it was determined that WP, omega-3 PUFA supplementation and bariatric surgery were not superior to each other.

Eosinophilic Cholecystitis and Eosinophils in Gallbladder Injuries: A Clinicopathological Analysis of 1050 Cholecystectomies.

"Eosinophilic cholecystitis" has been an elusive concept. Around 1050 consecutive cholecystectomies with chronic (CC, n = 895), subacute (SAC, n = 100), and acute cholecystitis (AC, n = 55) were reviewed for eosinophilic infiltration. Eosinophilic hot spots (>40 eosinophils/HPF) were seen in 63% of SAC and 35% of AC (vs. 6% of CC, p < 0.001). Eosinophils were mostly encountered in areas of wall thickening, revealing edema with early collagenization and young tissue-culture-type fibroblasts. However, in ten chronic cholecystitis patients (<1%), prominent eosinophilia with eosinophil-rich foci (>100 eosinophils/HPF) was noted. These ten cases, classified as "eosinophilic cholecystitis", were analyzed further: The patients were relatively young (mean age = 43 years), with a 9:1 female:male ratio. None had blood eosinophilia/eosinophilia syndromes. Although one had ulcerative colitis, others did not have any autoimmune diseases. The mean gallbladder wall thickness was 3.5 mm (vs. 4.2 mm in ordinary CC). In conclusion, eosinophils are a part of especially subacute injuries in the gallbladder. They are typically condensed in the areas of healing and appear to signify a distinctive state of injury in which there are erosions leading to slow/sustained exposure of the mural tissues to the bile contents that induce chemical injury/recruit eosinophils. Eosinophilic cholecystitis is a very uncommon occurrence and appears to be an exaggerated response in allergic patients who are prone to recruit eosinophils in reaction to injury.