415 patients with adenosquamous carcinoma of the pancreas: a population-based analysis of prognosis and survival

Preoperative Prognostic Factors in Resectable Pancreatic Cancer: State of the Art and Prospects

BACKGROUND

Only 15% to 20% of patients with pancreatic ductal adenocarcinoma (PDAC) have access to surgical resection, which represents the only chance of curative treatment. Current resection classifications are almost exclusively anatomic and do not correlate sufficiently with patient survival. It is essential to develop preoperative prognostic factors to distinguish patients at high risk of early postoperative recurrence from those who will have prolonged survival after surgery. In some cases, PDACs may present biomolecular differences reflecting their aggressiveness that are not yet assessable by the current clinical-biologic assessment. This study aimed to assess the preoperative prognostic factors that are already available and the future perspectives being developed.

METHOD

This study reviewed the literature using the PubMed public database for preoperative prognostic factors for resectable PDAC.

CONCLUSION

Validated preoperative prognostic factors, whether clinical, biologic, radiologic, or histologic, are very important in anticipating the course of each patient's disease. The identification of potential new prognostic biomarkers such as genomic, transcriptomic, and proteomic analyses and the dosage of circulating tumor DNA are very serious avenues to be developed, but the extraction and analysis techniques as well as the interpretation of their results need to be standardized in prospective studies.

Trends in pancreatic cancer incidence, prevalence, and survival outcomes by histological subtypes: a retrospective cohort study

Background

Pancreatic cancer (PC) is a heterogeneous disease with various histological and molecular subtypes. This study aimed to provide updated epidemiological estimates, survival outcomes, and treatment information for PC based on histological subtypes in the USA.

Methods

Data from the US Cancer Statistics and Surveillance, Epidemiology, and End Results (SEER)-17 databases (2000-2020) were used, including adults aged ≥20 years who were diagnosed with PC. The trends of incidence and prevalence by histological types were calculated by using the Joinpoint Regression model. Survival by histological type was analysed by using Kaplan-Meier curves and log-rank tests for group comparisons.

Results

Overall, the age-adjusted PC incidence per 100,000 increased from 9.54 to 12.05 in SEER-17 and from 9.75 to 12.19 in the US Cancer Statistics between 2001 and 2019. A further SEER-17 study comprised 113,681 PC cases that were sorted by histologic type between 2000 and 2020. The incidence per 100,000 of invasive intraductal papillary mucinous neoplasm (IPMN) and invasive mucinous cystic neoplasm (MCN) decreased (IPMN from 0.67 to 0.20 and MCN from 0.05 to 0.01) whereas that of other histological subtypes increased. Survival analysis indicated the best outcomes for solid pseudopapillary tumors and the poorest for squamous cell carcinoma. At the localized stage, the proportion of surgery in the treatment modalities varied depending on the biological behavior; the proportion of surgery for pancreatic neuroendocrine tumor was the highest and that for pancreatic ductal adenocarcinoma (PDAC) was the lowest. At the distant metastasis stage, a chemotherapy-based regimen remained the primary treatment of PDAC, pancreatic neuroendocrine tumor, and IPMN.

Conclusions

PC incidence and prevalence have been increasing. The incidence of IPMN and MCN decreased whereas that of other subtypes increased. Treatment distribution varies among subtypes and stages.

Characterization and clinical outcomes of rare biliary adenosquamous carcinoma

BACKGROUND

Data are scarce regarding biliary adenosquamous carcinoma (BASC) due to its low incidence. BASC displays a worse prognosis than adenocarcinoma and its specific treatment is still an unmet medical need. We conducted a description analysis of BASC including clinicopathologic parameters and treatment outcomes.

METHODS

All consecutive patients with histologically proven BASC diagnosed in six French hospitals between 2000 and 2022 were enrolled and described.

RESULTS

A total of 16 BASC, accounting for 1.4 % of all biliary tract carcinoma, were included and the BASC incidence increased steadily over the past 22 years. The median age at diagnosis was 70.7 years (min-max 31.4-82.0 years) with most women (62.5 %). At diagnosis, half of BASC patients had a localized stage. The primary tumor locations were shared between gallbladder cancers (n = 7) and cholangiocarcinoma (n = 7), with mainly an extra-hepatic disease (71.4 %). Median overall survival was 9.5 months (95 % CI = 2.1-14.8 months). A total of 13 (81.6 %) patients had undergone surgery with a median relapse-free survival of 3.8 months (95 % CI = 0.0-10.5 months). Five (38.5 %) patients received an adjuvant chemotherapy. A total of seven (43.8 %) patients were treated with chemotherapy for the occurrence of metastases with a median progression-free survival of 2.8 months (95 % CI = 0.8-4.1 months). No objective response was observed and stable disease was achieved in two patients (28.6 %).

CONCLUSIONS

BASC is a rare disease with an increased incidence, highlighting the diagnostic challenges. BASC population was associated with a poor prognostic and limited therapeutic response. Further molecular investigations should be performed to investigate new therapeutic options.

Primary adenosquamous carcinoma of the duodenum: A case report with literature review

Adenosquamous carcinoma (ASC) of the duodenum is a malignant tumor that combines adenocarcinoma and squamous cell carcinoma components. Case reports of ASC are rare, and our understanding of the complex clinicopathological features and treatment strategies for the disease remains incomplete. The current study presents a case of duodenal ASC and discusses the available literature on this rare condition. A 55-year-old male patient presented with a history of jaundice and fever, with pruritus and clay-colored stools. Preoperative investigations suggested an increase in transaminase, bilirubin and tumor markers. Enhanced magnetic resonance imaging of the abdomen revealed a mass in the descending duodenum and another in the pancreatic region, without distant metastases. An endoscopy of the upper gastrointestinal tract revealed an infiltrative growth mass invading the duodenal papilla in the descending part of the duodenum. The patient underwent a Whipple procedure. Histopathological and immunohistochemical examinations confirmed duodenal ASC. Although an R0 resection was performed, the patient developed hepatic metastases 2 months after surgery and succumbed 6 months post-surgery. This case underscores the aggressive nature of duodenal ASC and the need for further studies to develop effective treatment interventions.

Case report: Microsatellite instability-high pancreas adenosquamous carcinoma with postoperative liver metastasis recurrence treated with multimodality therapy achieving complete pathological response

Pancreatic adenosquamous carcinoma (PASC) is a rare subtype of pancreatic cancer (PC), with no established consensus on the optimal treatment for postoperative liver metastasis recurrence. We report a case of a 48-year-old male patient who underwent radical surgery and was pathologically diagnosed with microsatellite instability-high (MSI-H) PASC. The patient experienced liver metastasis recurrence following single-agent gemcitabine adjuvant chemotherapy. After one session of transarterial chemoembolization (TACE) with oxaliplatin, fluorouracil, and epirubicin, followed by six cycles of adjuvant chemotherapy with gemcitabine and nab-paclitaxel combined with sintilimab immunotherapy and bevacizumab targeted therapy, complete pathological regression of the liver metastasis was achieved. The patient has now reached a 24-month survival period and continues to be monitored at our center. This case illustrates the promise of the proposed treatment regimen, highlighting the significant potential of multimodality strategies in managing metastatic recurrence of MSI-H PASC.

Association of Mutant KRAS Alleles With Morphology and Clinical Outcomes in Pancreatic Ductal Adenocarcinoma

CONTEXT.—

Mutant KRAS is the main oncogenic driver in pancreatic ductal adenocarcinomas (PDACs). However, the clinical and phenotypic implications of harboring different mutant KRAS alleles remain poorly understood.

OBJECTIVE.—

To characterize the potential morphologic and clinical outcome differences in PDACs harboring distinct mutant KRAS alleles.

DESIGN.—

Cohort 1 consisted of 127 primary conventional PDACs with no neoadjuvant therapy, excluding colloid/mucinous, adenosquamous, undifferentiated, and intraductal papillary mucinous neoplasm-associated carcinomas, for which an in-house 42-gene mutational panel had been performed. A morphologic classification system was devised wherein each tumor was assigned as conventional, papillary/large duct (P+LD, defined as neoplastic glands with papillary structure and/or with length ≥0.5 mm), or poorly differentiated (when the aforementioned component was 60% or more of the tumor). Cohort 2 was a cohort of 88 PDACs in The Cancer Genome Atlas, which were similarly analyzed.

RESULTS.—

In both cohorts, there was significant enrichment of P+LD morphology in PDACs with KRAS G12V and G12R compared with G12D. In the entire combined cohort, Kaplan-Meier analyses showed longer overall survival (OS) with KRAS G12R as compared with G12D (median OS of 1255 versus 682 days, P = .03) and in patients whose PDACs displayed P+LD morphology as compared with conventional morphology (median OS of 1175 versus 684 days, P = .04). In the adjuvant-only subset, KRAS G12R had the longest OS compared with G12D, G12V, and other alleles (median OS unreached/undefined versus 1009, 1129, and 1222 days, respectively).

CONCLUSIONS.—

PDACs with different mutant KRAS alleles are associated with distinct morphologies and clinical outcomes, with KRAS G12R allele associated with P+LD morphology and longer OS when compared with G12D using Kaplan-Meier studies.

Clinical and Genomic Features of Classical and Basal Transcriptional Subtypes in Pancreatic Cancer

PURPOSE

Transcriptional profiling of pancreatic cancers has defined two main transcriptional subtypes: classical and basal. Initial data suggest shorter survival for patients with basal tumors and differing treatment sensitivity to FOLFIRINOX and gemcitabine plus nab-paclitaxel by transcriptional subtype.

EXPERIMENTAL DESIGN

We examined 8,743 patients with RNA sequencing from pancreatic cancers performed at Caris Life Sciences. Classical and basal subtypes were identified using purity independent subtyping algorithm on RNA sequencing, and two cohorts were analyzed: (i) the biomarker cohort included patients with complete molecular profiling data (n = 7,250) and (ii) the outcome cohort included patients with metastatic disease with available survival outcomes (n = 5,335). A total of 3,842 patients were shared between the two cohorts. Kaplan-Meier curves and Cox proportional hazards regression were used to assess patient survival.

RESULTS

In the biomarker cohort, 3,063 tumors (42.2%) were strongly classical (SC) and 2,015 tumors (27.8%) were strongly basal (SB). SC and SB tumors showed strong associations with histologic phenotypes and biopsy sites. SB tumors had higher rates of KRAS, TP53, and ARID1A mutations, lower rates of SMAD4 mutation, and transcriptional evidence of epithelial-mesenchymal transition. Sixty of 77 cases (78%) maintained their transcriptional subtype between temporally and/or spatially disparate lesions. In the outcome cohort, the SB subtype was associated with shorter overall survival time, regardless of whether they received FOLFIRINOX or gemcitabine plus nab-paclitaxel as first-line chemotherapy. The mutant KRAS allele type was prognostic of outcomes; however, this impact was restricted to SC tumors, whereas all mutant KRAS alleles had similarly poor outcomes in SB tumors.

CONCLUSIONS

The SB subtype is a strong independent predictor of worse outcomes, regardless of the up-front chemotherapy regimen used. Clinical trials should further investigate pancreatic cancer transcriptional subtypes as a prognostic and predictive biomarker.

Histological variants of pancreatic ductal adenocarcinoma: a survival analysis

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) can be classified into distinct histological subtypes based on the WHO nomenclature. The aim of this study was to compare the prognosis of conventional PDAC (cPDAC) against the other histological variants at the population level.

METHODS

The Surveillance, Epidemiology and End Results (SEER) database was used to identify patients with microscopically confirmed PDAC. These patients were divided into 9 histological subgroups. Overall survival was assessed using the Kaplan-Meier method and Cox regression models stratified by tumor histology.

RESULTS

A total of 159,548 patients with PDAC were identified, of whom 95.9% had cPDAC, followed by colloid carcinoma (CC) (2.6%), adenosquamous carcinoma (ASqC) (0.8%), signet ring cell carcinoma (SRCC) (0.5%), undifferentiated carcinoma (UC) (0.1%), undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) (0.1%), hepatoid carcinoma (HC) (0.01%), medullary carcinoma of the pancreas (MCP) (0.006%) and pancreatic undifferentiated carcinoma with rhabdoid phenotype (PUCR) (0.003%). Kaplan-Meier curves showed that PUCR had the worst prognosis (median survival: 2 months; 5-year survival: 0%), while MCP had the best prognosis (median survival: 41 months; 5-year survival: 33.3%). In a multivariable Cox model, several histological subtypes (i.e. CC, ASqC, SRCC, UCOGC) were identified as independent predictors of overall survival when compared to cPDAC.

CONCLUSION

PDAC is a heterogenous disease and accurate identification of variant histology is important for risk stratification, as these variants may have different biological behavior.

Wnt-deficient and hypoxic environment orchestrates squamous reprogramming of human pancreatic ductal adenocarcinoma

Human pancreatic cancer is characterized by the molecular diversity encompassing native duct-like and squamous cell-like identities, but mechanisms underlying squamous transdifferentiation have remained elusive. To comprehensively capture the molecular diversity of human pancreatic cancer, we here profiled 65 patient-derived pancreatic cancer organoid lines, including six adenosquamous carcinoma lines. H3K27me3-mediated erasure of the ductal lineage specifiers and hijacking of the TP63-driven squamous-cell programme drove squamous-cell commitment, providing survival benefit in a Wnt-deficient environment and hypoxic conditions. Gene engineering of normal pancreatic duct organoids revealed that GATA6 loss and a Wnt-deficient environment, in concert with genetic or hypoxia-mediated inactivation of KDM6A, facilitate squamous reprogramming, which in turn enhances environmental fitness. EZH2 inhibition counterbalanced the epigenetic bias and curbed the growth of adenosquamous cancer organoids. Our results demonstrate how an adversarial microenvironment dictates the molecular and histological evolution of human pancreatic cancer and provide insights into the principles and significance of lineage conversion in human cancer.

Successful pancreatectomy after conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for unresectable adenosquamous carcinoma of the pancreas: a case report

BACKGROUND

Adenosquamous carcinoma of the pancreas (ASCP) accounts for only 1-4% of all pancreatic exocrine cancers and has a particularly poor prognosis. The efficacy of chemotherapy for ASCP remains unknown because of the small number of cases, and few studies have evaluated conversion-intended chemotherapy.

CASE PRESENTATION

A 76-year-old woman was referred to our hospital because of epigastric pain and nausea. A preoperative contrast-enhanced multidetector row computed tomography (MDCT) scan revealed a 17 × 17 mm low-density tumor with an ill-defined margin at the arterial phase in the pancreatic head. The tumor involved the common hepatic artery, left hepatic artery bifurcated from the common hepatic artery, and gastroduodenal artery, and was in contact with the portal vein. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed an uptake in the pancreatic head but no evidence of distant metastasis. The tumor was diagnosed as an adenocarcinoma of the pancreatic head and staged unresectable because the common and left hepatic arteries were involved. Hence, the patient underwent seven courses of conversion-intended chemotherapy using gemcitabine and nab-paclitaxel for pancreatic ductal adenocarcinoma over 7 months. After chemotherapy, the tumor shrank to 10 × 10 mm on contrast-enhanced MDCT. Consequently, the boundary between the tumor and major vessels of the common and left hepatic arteries and the portal vein became clear, and the involvement of the arteries with the tumor was evaluated to be released. The contact of the tumor to the portal vein also reduced to less than half the circumference of the portal vein. FDG-PET showed decreased accumulation in the tumor. Hence, the tumor was judged resectable, and pancreaticoduodenectomy was performed. The tumor and major blood vessels were easily dissected and R0 resection was achieved. The patient experienced no major complications and was discharged on postoperative day 28. The tumor was revealed as ASCP via pathological examination. The patient is alive and recurrence-free seven months after surgery. This is the first report of successful R0 resection for an initially unresectable ASCP following conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen.

CONCLUSIONS

Conversion-intended chemotherapy using gemcitabine and nab-paclitaxel regimen may be effective for ASCP.

ECM1 and KRT6A are involved in tumor progression and chemoresistance in the effect of dexamethasone on pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) has a very poor prognosis. Neoadjuvant chemotherapy is an effective PDAC treatment option, but chemotherapy causes unfavorable side effects. Glucocorticoids (e.g., dexamethasone [DEX]) are administered to reduce side effects of chemotherapy for solid tumors, including pancreatic cancer. Glucocorticoids have both beneficial and detrimental effects, however. We investigated the functional changes and gene-expression profile alterations induced by DEX in PDAC cells. PDAC cells were treated with DEX, and the cell proliferation, migration, invasion, and chemosensitivity to gemcitabine (GEM) were evaluated. The results demonstrated decreased cell proliferative capacity, increased cell migration and invasion, and decreased sensitivity to GEM. A comprehensive genetic analysis revealed marked increases in ECM1 and KRT6A in DEX-treated PDAC cells. We evaluated the effects of ECM1 and KRT6A expression by using PDAC cells transfected with those genes. Neither ECM1 nor KRT6A changed the cells' proliferation, but each enhanced cell migration and invasion. ECM1 decreased sensitivity to GEM. We also assessed the clinicopathological significance of the expressions of ECM1 and KRT6A in 130 cases of PDAC. An immunohistochemical analysis showed that KRT6A expression dominated the poorly differentiated areas. High expressions of these two proteins in PDAC were associated with a poorer prognosis. Our results thus demonstrated that DEX treatment changed PDAC cells' functions, resulting in decreased cell proliferation, increased cell migration and invasion, and decreased sensitivity to GEM. The molecular mechanisms of these changes involve ECM1 and KRT6A, whose expressions are induced by DEX.

Case report: a case report of neoadjuvant mFOLFIRINOX leading to a partial pathologic response in pancreatic adenosquamous carcinoma

A female in her 60s with vague abdominal symptoms was found to have a pancreatic mass in her CT scan. A core needle biopsy done endoscopically demonstrated a poorly differentiated adenocarcinoma. The patient completed nine cycles of neoadjuvant systemic mFOLFIRINOX. Repeat staging demonstrated a partial radiographic response. She underwent an open pylorus-preserving pancreatoduodenectomy with segmental superior mesenteric vein resection with primary reconstruction (ISGPS Type 3). The final pathology demonstrated a poorly differentiated adenosquamous carcinoma, R1 margin status. The case report demonstrates the effect of mFOLFIRINOX on pancreatic adenosquamous (PASC) carcinoma with a review of the microscopic pictures following the neoadjuvant therapy. It can be postulated that glandular component being the major component in a PASC has a good response to mFOLFIRINOX like that seen in pancreatic ductal adenocarcinoma with some presumed effect on the squamous component as well. From the above case report, we are proposing that mFOLFIRINOX can be an effective chemotherapy regime in the management of PASC.

PD-L1 expression in pancreaticobiliary adenosquamous carcinoma: a single-institution case series

Background

The programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is a potent negative regulator of T-cell-mediated immune response that is upregulated in many neoplasms. Pancreaticobiliary adenosquamous carcinoma (PB-ASC) is an aggressive cancer that carries a poorer prognosis compared with pure pancreaticobiliary adenocarcinoma (PB-AC). To date, there is little published information regarding PD-L1 expression in PB-ASC. The aim of the study was to examine the relationship between PD-L1 expression and tumor-infiltrating lymphocytes in PB-ASC and PB-AC.

Methods

We evaluated 15 PB-ASCs (10 pancreatic, 5 gallbladder) and 34 control PB-ACs (22 pancreatic ductal, and 12 gallbladder) for tumor expression of PD-L1 using anti-PD-L1 (E1L3N) antibody. All tumors were classified into three immune phenotypes: immune inflamed (II), immune excluded (IE), and immune desert (ID) according to the distribution of tumor-infiltrating lymphocytes in tumor tissues.

Results

The frequency of PD-L1 expression was significantly higher in PB-ASC (10/15; 66.7%) than in PB-AC (3/34; 8.8%). In PB-ASC, PD-L1 expression occurred exclusively in the squamous component in six cases, exclusively in the glandular component in one case, and in both the squamous and the glandular components in three cases. PD-L1 expression in PB-ASC was irrespective of the tumor immune status, whereas its expression in PB-AC was observed only in tumors with the II or IE phenotype. The ID phenotype was relatively rare (4/15; 26.7%) in PB-ASC compared with PB-AC (22/34; 65%; P=0.02).

Conclusions

PB-ASCs are notably enriched in inflammatory response and showed significantly higher PD-L1 expression than PB-AC (P<0.001), suggesting a potential therapeutic role for immune checkpoint inhibitors in managing patients with PB-ASC.

Pancreatic Adenosquamous Carcinoma Discovered Upon a Resection for Neck Tuberculous Lymphadenitis: A Case Report

Cancer (including pancreatic cancer) can develop following a Mycobacterium tuberculosis infection within one year of tuberculosis infection. However, it is unclear whether tuberculosis infection increases the risk of developing adenosquamous carcinoma of the pancreas (ASCP), an extremely rare cancer with a poorer prognosis than pancreatic ductal adenocarcinoma (PDAC). Herein, we report a case of rapid growing ASCP discovered upon a resection for neck tuberculous lymphadenitis. The patient was a 57-year-old woman. An excisional biopsy of the swollen right neck lymph nodes revealed tuberculous lymphadenitis. One month after the biopsy, an abdominal computed tomography scan showed a 2.0 cm (diameter) ischemic tumor in the pancreatic tail. The tissue obtained using endoscopic ultrasonography-guided fine-needle aspiration led to the pathological diagnosis of ASCP. Two months after the biopsy, the tumor had grown to 3.5 cm (diameter), and invasion of the stomach and colon was suspected. Distal pancreatectomy, splenectomy, partial gastrectomy, and transverse colectomy were performed. The final diagnosis was ASCP (4.7 cm, pT3, pN0, cM0, and pStage IIA). Postoperative adjuvant combination chemotherapy combined with antituberculosis drugs was administered orally. We report the first case of rapidly growing adenosquamous carcinoma resected from the pancreas in association with tuberculous lymphadenitis. Additional evidence is needed to confirm that tuberculosis infection increases the risk of developing pancreatic adenosquamous cell carcinoma because its potential role in promoting squamous metaplasia is unclear.

Loss of chromosome 9p21 is associated with a poor prognosis in adenosquamous carcinoma of the pancreas

Adenosquamous carcinoma of the pancreas (ASCP) is a rare histological subtype of pancreatic cancer with a poor prognosis and a high metastasis rate. However, little is known about its genomic landscape and prognostic biomarkers. A total of 48 ASCP specimens and 98 pancreatic ductal adenocarcinoma (PDAC) tumour specimens were sequenced to explore the genomic landscape and prognostic biomarkers. The homozygous deletion of the 9p21.3 region (including CDKN2A, CDKN2B, and MTAP) (9p21 loss) occurred in both ASCP and PDAC, and a higher frequency of 9p21 loss was observed in ASCP (12.5% vs 2.0%, P = 0.022). Notably, 9p21 loss was significantly associated with poor disease-free survival (DFS) in ASCP patients (mDFS (Median DFS) = 4.17 vs 7.33 months, HR (Hazard Ratio) = 3.70, P = 0.009). The most common gene alterations in patients with ASCP were KRAS (96%), TP53 (81%), CDKN2A (42%), SMAD4 (21%), CDKN2B (13%), and FAT3 (13%). The mutation rates of ACVR2A (6.25% vs 0%), FANCA (6.25% vs 0%), RBM10 (6.25% vs 0%), and SPTA1 (8.33% vs 1.02%) were significantly higher in ASCP than in PDAC. In conclusion, we have comprehensively described the genomic landscape of the largest cohort of ASCP patients to date and highlight that 9p21 loss may be a promising prognostic biomarker for ASCP, which provides a molecular basis for prognosis prediction and new therapeutic strategies for ASCP.

Single-cell mapping identifies MSI+ cells as a common origin for diverse subtypes of pancreatic cancer

Identifying the cells from which cancers arise is critical for understanding the molecular underpinnings of tumor evolution. To determine whether stem/progenitor cells can serve as cells of origin, we created a Msi2-CreERT2 knock-in mouse. When crossed to CAG-LSL-MycT58A mice, Msi2-CreERT2 mice developed multiple pancreatic cancer subtypes: ductal, acinar, adenosquamous, and rare anaplastic tumors. Combining single-cell genomics with computational analysis of developmental states and lineage trajectories, we demonstrate that MYC preferentially triggers transformation of the most immature MSI2+ pancreas cells into multi-lineage pre-cancer cells. These pre-cancer cells subsequently diverge to establish pancreatic cancer subtypes by activating distinct transcriptional programs and large-scale genomic changes, and enforced expression of specific signals like Ras can redirect subtype specification. This study shows that multiple pancreatic cancer subtypes can arise from a common pool of MSI2+ cells and provides a powerful model to understand and control the programs that shape divergent fates in pancreatic cancer.

Rare Solid Pancreatic Lesions on Cross-Sectional Imaging

Several solid lesions can be found within the pancreas mainly arising from the exocrine and endocrine pancreatic tissue. Among all pancreatic malignancies, the most common subtype is pancreatic ductal adenocarcinoma (PDAC), to a point that pancreatic cancer and PDAC are used interchangeably. But, in addition to PDAC, and to the other most common and well-known solid lesions, either related to benign conditions, such as pancreatitis, or not so benign, such as pancreatic neuroendocrine neoplasms (pNENs), there are solid pancreatic lesions considered rare due to their low incidence. These lesions may originate from a cell line with a differentiation other than exocrine/endocrine, such as from the nerve sheath as for pancreatic schwannoma or from mesenchymal cells as for solitary fibrous tumour. These rare solid pancreatic lesions may show a behaviour that ranges in a benign to highly aggressive malignant spectrum. This review includes cases of an intrapancreatic accessory spleen, pancreatic tuberculosis, solid serous cystadenoma, solid pseudopapillary tumour, pancreatic schwannoma, purely intraductal neuroendocrine tumour, pancreatic fibrous solitary tumour, acinar cell carcinoma, undifferentiated carcinoma with osteoclastic-like giant cells, adenosquamous carcinoma, colloid carcinoma of the pancreas, primary leiomyosarcoma of the pancreas, primary and secondary pancreatic lymphoma and metastases within the pancreas. Therefore, it is important to determine the correct diagnosis to ensure optimal patient management. Because of their rarity, their existence is less well known and, when depicted, in most cases incidentally, the correct diagnosis remains challenging. However, there are some typical imaging features present on cross-sectional imaging modalities that, taken into account with the clinical and biological context, contribute substantially to achieve the correct diagnosis.

Genomic landscape and clinical features of rare subtypes of pancreatic cancer: analysis with the national database of Japan

BACKGROUND

Special subtypes of pancreatic cancer, such as acinar cell carcinoma (ACC), adenosquamous carcinoma (ASC), and anaplastic carcinoma of the pancreas (ACP), are rare, and so data on them are limited. Using the C-CAT database, we analyzed clinical and genomic characteristics of patients with these and evaluated differences on comparison with pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

We retrospectively reviewed data on 2691 patients with unresectable pancreatic cancer: ACC, ASC, ACP, and PDAC, entered into C-CAT from June 2019 to December 2021. The clinical features, MSI/TMB status, genomic alterations, overall response rate (ORR), disease control rate (DCR), and time to treatment failure (TTF) on receiving FOLFIRINOX (FFX) or GEM + nab-PTX (GnP) therapy as first-line treatment were evaluated.

RESULTS

Numbers of patients with ACC, ASC, ACP, and PDAC were 44 (1.6%), 54 (2.0%), 25 (0.9%), and 2,568 (95.4%), respectively. KRAS and TP53 mutations were prevalent in ASC, ACP, and PDAC (90.7/85.2, 76.0/68.0, and 85.1/69.1%, respectively), while their rates were both significantly lower in ACC (13.6/15.9%, respectively). Conversely, the rate of homologous recombination-related (HRR) genes, including ATM and BRCA1/2, was significantly higher in ACC (11.4/15.9%) than PDAC (2.5/3.7%). In ASC and ACP, no significant differences in ORR, DCR, or TTF between FFX and GnP were noted, while ACC patients showed a trend toward higher ORR with FFX than GnP (61.5 vs. 23.5%, p = 0.06) and significantly more favorable TTF (median 42.3 vs. 21.0 weeks, respectively, p = 0.004).

CONCLUSIONS

ACC clearly harbors different genomics compared with PDAC, possibly accounting for differences in treatment efficacy.

Chemotherapy in advanced pancreatic adenosquamous carcinoma: A retrospective multicenter AGEO study

Pancreatic adenosquamous carcinoma (PASC) account for <5% of pancreatic malignancies. The efficacy of modern chemotherapy regimens in patients with advanced PASC is unknown. Patients with advanced PASC from 2008 to 2021 were consecutively included in this retrospective multicenter study. Overall survival (OS) and progression-free survival (PFS) were evaluated by Kaplan-Meier method. Ninety-four PASC from 16 French centers were included (median age, 67.3 years; males, 56.4%; metastatic disease, 85.1%). The first-line treatment was chemotherapy for 79 patients (84.0%) (37 FOLFIRINOX (FX), 7 Gemcitabine-nab paclitaxel (GN) and 35 for all other regimen) or best supportive care (BSC) alone for 15 patients (16.0%). No significant difference was observed between FX and GN in terms of PFS (P = .67) or OS (P = .5). Modern regimens pooled together (FX and GN) as compared to all others chemotherapy regimens showed an improvement of overall response rate (39.5% and 9.7%, P = .002), PFS (median, 7.8 vs 4.7 months, P = .02) and OS (median, 12.7 vs 9.2 months, P = .35). This large study evaluating first-line treatment regimens in advanced PASC suggests that modern regimens as FX or GN may be preferable to all other chemotherapy regimens. These results deserve confirmation in prospective studies.

Fully automated magnetic resonance imaging-based radiomics analysis for differentiating pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma

PURPOSE

To develop and validate an automated magnetic resonance imaging (MRI)-based model to preoperatively differentiate pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included patients with surgically resected, histopathologically confirmed PASC or PDAC who underwent MRI between January 2011 and December 2020. According to time of treatment, they were divided into training and validation sets. Automated deep-learning-based artificial intelligence was used for pancreatic tumor segmentation. Linear discriminant analysis was performed with conventional MRI and radiomic features to develop clinical, radiomics, and mixed models in the training set. The models' performances were determined from their discrimination and clinical utility. Kaplan-Meier and log-rank tests were used for survival analysis.

RESULTS

Overall, 389 and 123 patients with PDAC (age, 61.37 ± 9.47 years; 251 men) and PASC (age, 61.99 ± 9.82 years; 78 men) were included, respectively; they were split into the training (n = 358) and validation (n = 154) sets. The mixed model showed good performance in the training and validation sets (area under the curve: 0.94 and 0.96, respectively). The sensitivity, specificity, and accuracy were 76.74%, 93.38%, and 89.39% for the training set, respectively, and 67.57%, 97.44%, and 90.26% for the validation set, respectively. The mixed model outperformed the clinical (p = 0.001) and radiomics (p = 0.04) models in the validation set. Log-rank test revealed significantly longer survival in the predicted PDAC group than in the predicted PASC group (p = 0.003), according to the mixed model.

CONCLUSION

Our mixed model, which combined MRI and radiomic features, can be used to differentiate PASC from PDAC.

Adenosquamous carcinoma coexisting with intraductal papillary mucinous neoplasm of the pancreas: a case report

BACKGROUND

Adenosquamous carcinoma of the pancreas is a rare variant, with a worse prognosis than pancreatic ductal adenocarcinoma; moreover, it has characteristic clinical and histopathological features. Studies have mentioned the differentiation of intraductal papillary mucinous neoplasms into mucinous/tubular adenocarcinomas; however, their transdifferentiation into adenosquamous carcinoma remains unclear.

CASE PRESENTATION

An 80-year-old Japanese woman was referred to our hospital for further examination of multiple pancreatic cysts. Enhanced computed tomography after close follow-up for 6 years revealed a new nodule with poor enhancement on the pancreatic body. Distal pancreatectomy and splenectomy were performed. Histopathological examination revealed an adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms; moreover, the intraductal papillary mucinous neoplasms lacked continuity with the adenosquamous carcinoma. Immunohistochemical analysis revealed squamous cell carcinoma and differentiation from adenocarcinoma to squamous cell carcinoma. Gene mutation analysis revealed KRASG12D and KRASG12R mutations in adenosquamous carcinoma components and intraductal papillary mucinous neoplasm lesions, respectively, with none showing the mutation of GNAS codon 201. The final histopathological diagnosis was adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms of the pancreas.

CONCLUSIONS

This is the rare case of adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms of the pancreas. To investigate the underlying transdifferentiation pathway of intraductal papillary mucinous neoplasms into this rare subtype of pancreatic cancer, we explored gene mutation differences as a clinicopathological parameter.

Pancreatic adenosquamous carcinoma: A population level analysis of epidemiological trends and prognosis

BACKGROUND

The incidence and mortality of pancreatic adenosquamous carcinoma (PASC) have received little attention. The goal of our study was to explore the overall epidemiological trend of PASC at the population level.

METHODS

The Surveillance, Epidemiology, and End Results database was used to collect the incidence, incidence-based (IB) mortality, and patient details for PASC from 2000 to 2017. The Joinpoint regression tool was used to examine the trends in incidence and IB mortality. The Kaplan-Meier approach was used for survival analysis. Univariate and multivariate Cox regression analyses were used to determine the independent prognostic factors.

RESULTS

We included 815 patients with PASC in the study. The incidence of PASC continuously increased from 2000 to 2017, with an annual percentage change (APC) of 3.9% (95% CI: 2.2%-5.7%, p < 0.05). IB mortality also increased continuously, with an APC of 5.0% (95% CI: 2.5%-7.6%, p < 0.05). Multivariate Cox regression analysis revealed that age, treatment, regional lymph node involvement, and tumor size were independent prognostic factors. Nomograms were created for PASC to predict 1- and 2-year survival probabilities, respectively.

CONCLUSIONS

The incidence and IB mortality of PASC had a sustained and rapid increase, indicating that the preventive and treatment measures for PASC were not ideal. We must identify the significance of this condition as soon as possible, and commit greater attention and resources to PASC research.

The PD-L1 Expression and Tumor-Infiltrating Immune Cells Predict an Unfavorable Prognosis in Pancreatic Ductal Adenocarcinoma and Adenosquamous Carcinoma

The tumor microenvironment (TME) plays a vital role in the development, progression, and metastasis of pancreatic cancer (PC). The composition of the TME and its potential prognostic value remains to be fully understood, especially in adenosquamous carcinoma of pancreas (ASCP) patients. Immunohistochemistry was used to explore the clinical significance of CD3, CD4, CD8, FoxP3, and PD-L1 expression within the TME and to identify correlations with the prognosis of PC in a series of 29 patients with ASCP and 54 patients with pancreatic ductal adenocarcinoma (PDAC). Data from the Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) were accessed to obtain the scRNA-seq data and transcriptome profiles. Seurat was used to process the scRNA-seq data, and CellChat was used to analyze cell-cell communication. CIBERSORT was used to approximate the constitution of tumor-infiltrating immune cell (TICs) profiles. Higher levels of PD-L1 were linked with a shorter overall survival in ASCP (p = 0.0007) and PDAC (p = 0.0594). A higher expression of CD3+ and CD8+ T-cell infiltration was significantly correlated with a better prognosis in PC. By influencing the composition of tumor-infiltrating immune cells (TICs), high levels of PD-L1 expression are linked with a shorter overall survival in ASCP and PDAC.

Partial response in non-resectable adenosquamous carcinoma of the pancreas with high tumour mutation burden treated with gemcitabine, nab-paclitaxel and pembrolizumab

A previously healthy man in his 60s was diagnosed with a rare histological subtype of pancreatic cancer, adenosquamous carcinoma. After somatic mutation profiling, it was found that the tumour had microsatellite instability status high and a high tumour mutational burden. The patient was started on combination therapy with gemcitabine, nab-paclitaxel and pembrolizumab. Tumour size and biomarkers showed a dramatic response eventually leading to the patient being transitioned to maintenance therapy with pembrolizumab. The patient has demonstrated continued response since the start of the treatment. This is the first report in the literature showing a sustained response in this type of neoplasm that was treated with a checkpoint inhibitor, and thus adds to the evidence supporting universal somatic testing in all pancreatic cancers for a tailored approach to therapy.

Research advances and treatment perspectives of pancreatic adenosquamous carcinoma

BACKGROUND

As a malignant tumor, pancreatic cancer has an extremely low overall 5-year survival rate. Pancreatic adenosquamous carcinoma (PASC), a rare pancreatic malignancy, owns clinical presentation similar to pancreatic ductal adenocarcinoma (PDAC), which is the most prevalent pancreatic cancer subtype. PASC is generally defined as a pancreatic tumor consisting mainly of adenocarcinoma tissue and squamous carcinoma tissue. Compared with PDAC, PASC has a higher metastatic potential and worse prognosis, and lacks of effective treatment options to date. However, the pathogenesis and treatment of PASC are not yet clear and are accompanied with difficulties.

CONCLUSION

The present paper systematically summarizes the possible pathogenesis, diagnosis methods, and further suggests potential new treatment directions through reviewing research results of PASC, including the clinical manifestations, pathological manifestation, the original hypothesis of squamous carcinoma and the potential regulatory mechanism. In short, the present paper provides a systematic review of the research progress and new ideas for the development mechanism and treatment of PASC.

Non-enhanced magnetic resonance imaging-based radiomics model for the differentiation of pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma

Purpose

To evaluate the diagnostic performance of radiomics model based on fully automatic segmentation of pancreatic tumors from non-enhanced magnetic resonance imaging (MRI) for differentiating pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC).

Materials and methods

In this retrospective study, patients with surgically resected histopathologically confirmed PASC and PDAC who underwent MRI scans between January 2011 and December 2020 were included in the study. Multivariable logistic regression analysis was conducted to develop a clinical and radiomics model based on non-enhanced T1-weighted and T2-weighted images. The model performances were determined based on their discrimination and clinical utility. Kaplan-Meier and log-rank tests were used for survival analysis.

Results

A total of 510 consecutive patients including 387 patients (age: 61 ± 9 years; range: 28-86 years; 250 males) with PDAC and 123 patients (age: 62 ± 10 years; range: 36-84 years; 78 males) with PASC were included in the study. All patients were split into training (n=382) and validation (n=128) sets according to time. The radiomics model showed good discrimination in the validation (AUC, 0.87) set and outperformed the MRI model (validation set AUC, 0.80) and the ring-enhancement (validation set AUC, 0.74).

Conclusions

The radiomics model based on non-enhanced MRI outperformed the MRI model and ring-enhancement to differentiate PASC from PDAC; it can, thus, provide important information for decision-making towards precise management and treatment of PASC.

Pancreatic Adenosquamous Carcinoma: A Rare Pathological Subtype of Pancreatic Cancer

Pancreatic adenosquamous carcinoma (PASC) is a rare pathological subtype of pancreatic cancer (PC), with a worse prognosis than pancreatic ductal adenocarcinoma (PDAC). Due to its rarity, our knowledge of PASC and its biological characteristics are limited. In this review, we provide an overview of the histogenesis, genetic features, diagnosis, treatment, and prognosis of PASC, as well as pancreatic squamous cell carcinoma (PSCC). The information provided here may help to clarify our understanding of PASC and provide useful avenues for further research on this disease.

Chemotherapy is associated with improved survival in a national cohort of stage IV pancreatic adenosquamous carcinoma

Background

Pancreatic adenosquamous carcinoma (PASC) is a rare cancer that often presents with advanced disease and carries a grim prognosis. PASC is defined by the presence of at least 30% malignant squamous cells in the presence of malignant ductal adenocarcinoma. The utility of chemotherapy in the setting of metastatic disease is unknown.

Methods

In this cross-sectional analysis, patients with stage IV PASC diagnosed between 2006 and 2016 were abstracted from the National Cancer Data Base. Patients were then categorized according to whether they received chemotherapy. Multivariable logistic regression analysis was done to determine the odds of receiving palliative chemotherapy. Overall survival analysis was performed using Kaplan-Meier analysis. A Cox proportional hazard multivariable model was generated to account for potential confounders.

Results

There were 698 patients with metastatic PASC available for analysis, including 400 patients (57.3%) who received chemotherapy and 298 patients (42.3%) who did not receive chemotherapy. Median overall survival was significantly longer for patients who received chemotherapy (5.2 vs. 1.5 months, P<0.001; HR 0.328, 95% CI: 0.272-0.397). Compared to patients who did not receive chemotherapy, patients who received chemotherapy were younger (mean 62.6 vs. 70.1 years old; P<0.001) and more likely to have no comorbidities (72.0% vs. 58.7%; P<0.001). In multivariate analysis, chemotherapy was the only factor independently associated with improved survival.

Conclusions

This is the largest study on PASC conducted to date and the first to evaluate whether chemotherapy is associated with improved survival for patients with metastatic disease. We found that palliative chemotherapy was associated with significant prolongation of life. However, overall prognosis remained dismal despite chemotherapy and novel treatment approaches are needed to improve long-term survival.

Efficacy of chemotherapy for patients with metastatic or recurrent pancreatic adenosquamous carcinoma: A multicenter retrospective analysis

BACKGROUND/OBJECTIVES

Pancreatic adenosquamous carcinoma (PASC) is a rare variant of pancreatic ductal adenocarcinoma (PDAC). The usual treatment for metastatic or recurrent PASC is systemic chemotherapy in accordance with the PDAC treatment strategy. This study aimed to investigate the efficacy of chemotherapy, especially the benefit of recent combination therapies, in patients with metastatic or recurrent PASC.

METHODS

We conducted a multicenter retrospective analysis of 116 patients with metastatic or recurrent PASC treated with first-line chemotherapy between April 2001 and December 2017 at 24 Japanese institutions.

RESULTS

Combination chemotherapies included gemcitabine + nab-paclitaxel (GnP, n = 28), fluorouracil/leucovorin + irinotecan + oxaliplatin (FFX, n = 10), gemcitabine + S-1 (GS, n = 10), and others (n = 9). Monotherapies included gemcitabine (n = 51) and S-1 (n = 8). The median overall survival (OS) was 6.5, 7.3, and 4.3 months for the whole cohort, the combination therapy group, and the monotherapy group, respectively. Multivariate analysis indicated that combination therapy showed a better trend in OS than monotherapy (hazard ratio = 0.68; 95% confidence interval, 0.38-1.20). GnP or FFX were selected in 58.7% of patients after FFX was approved in Japan, and revealed a median OS, median progression-free survival, and objective response rate of 7.3 months, 2.8 months, and 26.9% in GnP and 7.2 months, 2.3 months, and 20.0% in FFX respectively.

CONCLUSIONS

This study suggests that combination therapy may be more effective than monotherapy. GnP and FFX showed similar and clinically meaningful efficacy for patients with metastatic or recurrent PASC.

Endosonography-Guided Tissue Acquisition for Diagnosis of Squamous Carcinoma of the Pancreas: A Report of Three Cases

While approximately 85% of neoplasms are ductal pancreatic adenocarcinomas (DPA), adenosquamous pancreatic carcinoma (APC) is a rare subtype of pancreatic cancer that exhibits aggressive behavior and poor prognosis. The authors report three cases of primary APC diagnosed through endoscopic ultrasound-guided tissue acquisition (EUS-TA) using the new ProCore 20G needle, which had been developed to improve fine-needle aspiration results by providing more tissue for histopathology. Given its ability for microcore retrieval, pancreatic stroma examination, and excellent histopathology results, EUS-TA has exhibited exceptional diagnostic yield among patients with solid pancreatic lesions. All three APC cases presented herein had been accurately diagnosed using immunohistochemistry after microcore acquisition.

Adenosquamous carcinoma of the pancreas: two case reports and review of the literature

Background

Among the total reported cases of pancreatic duct adenocarcinomas, around 1–2.9% are adenosquamous carcinomas of the pancreas. Due to limited data, preoperative diagnosis is a great challenge for physicians, and it is usually set post-operational, based on the pathologist report. We operated on two cases of adenosquamous carcinoma of the pancreas, which we present alongside the operation and treatment planning.

Case report

A 69-year-old Caucasian female and a 63-year-old Caucasian male presented themselves with jaundice in our department. The abdomen computed tomography and magnetic resonance imaging scans revealed lesions of the pancreas. A pancreas–duodenumectomy was performed in both patients, and the post-operational histology analysis revealed adenosquamous carcinoma of the pancreas head. The patients were discharged in good condition and received further chemotherapy treatment after surgery.

Conclusions

Two case reports of adenosquamous carcinoma of the pancreas are described here, which both underwent surgery resection. The limited available literature on this topic substantially limits the knowledge and guidance on treatment. A summarization of the available literature is attempted, alongside a description of possible fields of future research.

Delayed local recurrence of pancreatic adenosquamous cell carcinoma after curative surgery: A case report

Introduction

Pancreatic adenosquamous cell carcinoma (PASC) is a rare histological type of pancreatic malignancy with a particularly poor prognosis, even after curative surgery. Here, we describe the long-term prognosis of PASC in a patient who developed delayed local recurrence of the remnant pancreas after successful distal pancreatectomy, together with a literature review.

Presentation of case

A 59-year-old woman had a history of hepatitis C. Computed tomography revealed a hypointense mass in the pancreatic body in the arterial phase of the study. Magnetic resonance imaging revealed a tumor (20 mm) in the pancreatic body and dilatation of the main pancreatic duct at the periphery of the tumor. The patient was diagnosed with resectable pancreatic ductal adenocarcinoma and underwent distal pancreatectomy with lymphadenectomy; her postoperative course was uneventful. Immunohistochemical analysis of the resected specimen confirmed the diagnosis of tumor node metastasis [TNM] classification T2N1M0 stage IIB. Five years after curative surgery, following adjuvant systemic chemotherapy with S-1, local recurrence in the remnant pancreas occurred, which invaded the common hepatic artery and celiac pleural plexus. Systemic chemotherapy with gemcitabine and abraxiane is currently underway.

Discussion

Curative surgery significantly affects the prognosis of patients with PASC. Adjuvant chemotherapy may prolong the survival of these patients. Delayed remnant pancreatic recurrence should be considered during the surveillance of pancreatic cancer after curative resection.

Conclusion

We present a case of PASC in a patient who developed local recurrence in the remnant pancreas 5 years after successful distal pancreatectomy. Special attention should be paid not only to early recurrence but also to delayed local recurrence in PASC.

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Pancreatic adenosquamous cell carcinoma (PASC) is a rare histological type of pancreatic malignancy

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We describe the long-term prognosis of PASC in a patient who developed delayed local recurrence of the remnant pancreas after distal pancreatectomy.

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Delayed remnant pancreatic recurrence should be considered during the surveillance of pancreatic cancer after curative resection.

Single-cell sequencing reveals heterogeneity between pancreatic adenosquamous carcinoma and pancreatic ductal adenocarcinoma with prognostic value

Pancreatic adenosquamous carcinoma (ASPC) is a rare subtype of pancreatic cancer with lethal malignancy, and few studies have focused on the heterogeneity of ASPC. Here, we performed a single-cell sequencing procedure on pancreatic tumor tissue from an ASPC patient and a patient with high-grade intraductal papillary mucinous neoplasm (IPMN). Through the combined analysis of single-cell sequencing data from five pancreatic ductal adenocarcinoma (PDAC) patients, one IPMN patient, and one ASPC patient in a public database, we identified 11 main types of cells, including macrophages, B cells, cancer stem cells, ductal cells, fibroblasts, endo/stellate cells, neutrophils, acinar cells, T cells, natural killer (NK) cells, dendritic cells, and mast cells. Then, the different characteristics and differentiation paths of the immune microenvironment among IPMN, ASPC, and PDAC in macrophages, T cells, and cancer-associated fibroblasts (CAFs) were identified through multiple bioinformatics analyses. Two novel special cancer-associated fibroblasts were identified as nCAFs and imCAFs. Then, cancer cells in duct cells were identified using the infercnv software. Two ASPC-specific subgroups of cancer cells with squamous cell features were identified. Finally, the identified specific CAFs and cancer cells were mapped to TCGA-PAAD cohort through the cibersoftx software. All of these identified subgroups were calculated to have a significant prognostic value in pancreatic cancer patients. These findings will promote the clinical application of single-cell sequencing data of pancreatic cancer and deepen our understanding of ASPC.

Clinical Outcome and Prognostic Factors of Pancreatic Adenosquamous Carcinoma Compared to Ductal Adenocarcinoma-Results from the German Cancer Registry Group

Background: Adenosquamous carcinoma of the pancreas (ASCP) is a rare malignancy and its pathophysiology is poorly understood. Sparse clinical data suggest that clinical outcome and overall survival is worse in comparison to common pancreatic ductal adenocarcinoma (PDAC). Methods: We evaluated clinical outcome and prognostic factors for overall survival of patients with ASCP in comparison to patients with PDAC recorded between 2000 and 2019 in 17 population-based clinical cancer registries at certified cancer centers within the Association of German Tumor Centers (ADT). Results: We identified 278 (0.5%) patients with ASCP in the entire cohort of 52,518 patients with pancreatic cancer. Significantly, more patients underwent surgical resection in the cohort of ASCP patients in comparison to patients with PDAC (p < 0.001). In the cohort of 142 surgically resected patients with ASCP, the majority of patients was treated by pancreatoduodenectomy (44.4%). However, compared to the cohort of PDAC patients, significantly more patients underwent distal pancreatectomy (p < 0.001), suggesting that a significantly higher proportion of ASCP tumors was located in the pancreatic body/tail. ASCPs were significantly more often poorly differentiated (G3) (p < 0.001) and blood vessel invasion (V1) was detected more frequently (p = 0.01) in comparison with PDAC. Median overall survival was 6.13 months (95% CI 5.20−7.06) for ASCP and 8.10 months (95% CI 7.93−8.22) for PDAC patients, respectively (p = 0.094). However, when comparing only those patients who underwent surgical resection, overall survival of ASCP patients was significantly shorter (11.80; 95% CI 8.20−15.40 months) compared to PDAC patients (16.17; 95% CI 15.78−16.55 months) (p = 0.007). ASCP was a highly significant prognostic factor for overall survival in univariable regression analysis (p = 0.007) as well as in multivariable Cox regression analysis (HR 1.303; 95% CI 1.013−1.677; p = 0.039). Conclusions: In conclusion, ASCP showed poorer differentiation and higher frequency of blood vessel invasion indicative of a more aggressive tumor biology. ASCP was a significant prognostic factor for overall survival in a multivariable analysis. Overall survival of resected ASCP patients was significantly shorter compared to resected PDAC patients. However, surgical resection still improved survival significantly.

Development and external validation of a dynamic nomogram to predict the survival for adenosquamous carcinoma of the pancreas

Objective

We aimed to develop a nomogram to predict the survival and prognosis of adenosquamous carcinoma of the pancreas (ASCP).

Background

Adenosquamous carcinoma of the pancreas (ASCP) is a relatively rare histological subtype of pancreatic exocrine neoplasms. It was reported a worse survival in ASCP than in pancreatic adenocarcinoma (PDAC). Prediction of ASCP prognosis is of great importance.

Methods

Histologically confirmed ASCP patients from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program database were finally enrolled and divided into development and internal validation cohorts. Moreover, a multi-center cohort of 70 patients from China was registered as the external validation. A nomogram was developed based on independent predictors of ASCP determined in multivariable analysis.

Results

A total of 233 patients from SEER were finally included. Univariate and Multivariate analysis showed that tumor size, radiotherapy, chemotherapy, and lymph node ratio (LNR) were considered the independent prognostic indicators. We developed a nomogram according to these four parameters. The C index of the nomogram in the development cohort was 0.696. Through analysis of the area under the curve (AUC) of the different cohorts, we observed that the predictive efficacy of the nomogram for 1-, and 2-year overall survival (OS) were better than those of the American Joint Committee on Cancer (AJCC) TNM (8th) staging system both in the development and validation cohort. External validation confirmed that 1-year survival is 67.2% vs. 29.7%, similar to the internal cohort analysis.

Conclusion

The nomogram showed good performance in predicting the survival of ASCP. It could help surgeons to make clinical decisions and develop further plans.

Genetics and Therapeutic Responses to Tumor-Infiltrating Lymphocyte Therapy of Pancreatic Cancer Patient-Derived Xenograft Models

Background and Aims

Pancreatic cancer is the seventh leading cause of cancer-related deaths worldwide. Checkpoint immunotherapy has not yet shown encouraging results in pancreatic cancer possibly because of a poor immunogenicity and/or an immune suppressive microenvironment. The aim of this study was to develop patient-derived xenograft (PDX) models, compare their genetics to the original biopsies, and assess if autologous tumor-infiltrating lymphocytes (TILs) would have antitumoral activity in pancreatic cancer.

Methods

We subcutaneously transplanted tumors from 29 patients into NOG mice to generate PDX models. We established TIL cultures and injected them into PDX mice. We analyzed histology and genetics of biopsies and PDX tumors.

Results

Tumor growths were confirmed in 11 of 29 transplantations. The PDX tumors histologically resembled their original biopsies, but because stromal cells in the PDX model tumors were from mouse, their gene expression differed from the original biopsies. Immune checkpoint ligands other than programmed death ligand-1 (PD-L1) were expressed in pancreatic cancers, but PD-L1 was rarely expressed. When it was expressed, it correlated with tumor take in PDX models. One of the 3 tumors that expressed PD-L1 was an adenosquamous cancer, and another had a mismatch repair deficiency. TILs were expanded from 6 tumors and were injected into NOG or human interleukin-2 transgenic-NOG mice carrying PDX tumors. Regression of tumors could be verified in human interleukin-2 transgenic-NOG mice in 3 of the 6 PDX models treated with autologous TILs, including the adenosquamous PDX model.

Conclusion

PDX models of pancreatic cancer can be used to learn more about tumor characteristics and biomarkers and to evaluate responses to adoptive cell therapy and combination therapies. The major benefit of the model is that modifications of T cells can be tested in an autologous humanized mouse model to gain preclinical data to support the initiation of a clinical trial.

Epidemiology and survival outcomes in adenosquamous carcinoma: a population-based study

BACKGROUND

The relationship between the location of the primary tumor and survival of adenosquamous carcinoma (ASC) remains poorly understood. This study aimed to evaluate the impact of primary tumor location on the survival outcome of patients with ASC.

METHODS

Patients with ASC were extracted from the Surveillance, Epidemiology, and End Results (SEER) database with ≥ 150 cases per tumor location. The Kaplan-Meier method was used to generate survival curves and differences among them were compared using the log-rank test. On the other hand, Cox proportional hazards models were used to evaluate factors that had independent predictive effects on cancer-specific survival (CSS).

RESULTS

A total of 14,829 eligible patients with ASC were included in this study. Lung and bronchus ASC accounted for 51.1%, followed by the cervix uteri (17.0%), corpus uteri (13.9%), pancreas (4.9%), esophagus (3.1%), gallbladder (2.5%), stomach (2.2%), colon and rectum (2.0%), head and neck (1.8%), and breast ASC (1.3%). The 5-year CSS of breast, cervix uteri, colon and rectum, corpus uteri, esophagus, gallbladder, head and neck, lung and bronchus, pancreas, and stomach ASC was 76.9%, 66.0%, 34.8%, 72.9%, 12.0%, 10.8%, 45.0%, 24.7%, 4.3%, and 17.3%, respectively. COX analysis demonstrated that the primary tumor location was an independent prognostic factor for CSS. Besides, the breast, uterine corpus, and cervix as well as head and neck ASC were significantly associated with better prognosis, while pancreas and gallbladder ASC were significantly associated with poor CSS; stomach and colorectal were roughly the same as ASC prognosis.

CONCLUSION

Our study showed that the CSS of patients with ASC depends on the location of the primary tumor. Besides, tumor location is an important factor that should guide the use of chemotherapy and radiation.

Survival Analysis and Prediction Model of ASCP Based on SEER Database

Background

This study aims to compare the incidence and clinical and survival characteristics of adenosquamous carcinoma of the pancreas (ASCP) and adenomatous carcinoma of the pancreas (ACP), analyze the survival factors of ASCP and construct a prognostic model.

Method

Patients diagnosed with pancreatic cancer from 2000 to 2018 are selected from the SEER database. ASCP and ACP are compared in terms of epidemiology, clinical characteristics and prognosis. Cases are matched in a 1:2 ratio, and survival analysis is performed. The Cox proportional hazard model is used to determine covariates related to overall survival (OS), and an ASCP prognosis nomogram is constructed and verified by consistency index (C-index), calibration chart and decision curve analysis (DCA). The accuracy of the model is compared with that of AJCC.Stage and SEER.Stage to obtain the area under the receiver operating characteristic (ROC) curve.

Results

the age-adjusted incidence of ACP increased significantly over time from 2000 to 2008 and from 2008 to 2018 (P < 0.05). APC was 2.01% (95% CI: 1.95–2.21) and 1.08% (95% CI: 0.93–1.25) respectively. The age-adjusted incidence of ASCP increased with time from 2000 to 2018 (P < 0.05) and APC was 3.64% (95% CI: 3.25–4.01).After propensity score matching (PSM), the OS and cancer-specific survival (CSS) of ACP are better than those of ASCP. The survival time of ASCP is significantly improved by the combined treatment of surgery + chemotherapy + radiotherapy, with a median OS of 31 months. Cox proportional hazard regression analysis shows that age, race, surgery, radiotherapy, chemotherapy and tumor size are independent factors affecting the prognosis. DCA and area under the curve (AUC) value shows that the model has good discrimination ability.

Conclusion

The OS prognosis of ASCP is worse than that of ACP, and the nomogram has high accuracy for the prognosis prediction of ASCP.

Current Pathology Model of Pancreatic Cancer

Pancreatic cancer (PC) is one of the most aggressive and lethal malignant neoplasms, ranking in seventh place in the world in terms of the incidence of death, with overall 5-year survival rates still below 10%. The knowledge about PC pathomechanisms is rapidly expanding. Daily reports reveal new aspects of tumor biology, including its molecular and morphological heterogeneity, explain complicated "cross-talk" that happens between the cancer cells and tumor stroma, or the nature of the PC-associated neural remodeling (PANR). Staying up-to-date is hard and crucial at the same time. In this review, we are focusing on a comprehensive summary of PC aspects that are important in pathologic reporting, impact patients' outcomes, and bring meaningful information for clinicians. Finally, we show promising new trends in diagnostic technologies that might bring a difference in PC early diagnosis.

Humeral metastases: an unusual presentation of pancreatic cancer

In patients presenting with symptomatic bone metastases, the usual primary malignancies are breast, prostate, thyroid, lung and kidney. Pancreatic cancers are an uncommon cause of bone metastasis and, when they are, it is typically to the axial skeleton. We present the case of a 77-year-old woman who presented to our emergency department with right arm pain. Investigation demonstrated a metastatic lesion with impending pathological fracture. Further investigation found a necrotic pancreatic mass in the tail of the pancreas. Histopathology from the humeral metastasis was consistent with metastatic adenosquamous carcinoma of pancreatic origin. The humerus metastasis was successfully managed with an intramedullary nail. This case highlights an unusual presentation of pancreatic adenocarcinoma with humeral bone metastasis.

Development and Validation of Nomograms to Predict Overall Survival and Cancer-Specific Survival in Patients With Pancreatic Adenosquamous Carcinoma

Background

Pancreatic adenosquamous carcinoma (PASC) is a heterogeneous group of primary pancreatic cancers characterized by the coexistence of both glandular and squamous differentiation. The aim of this study was to develop nomograms to predict survival outcomes in patients with PASC.

Methods

In this retrospective study, data on PASC, including clinicopathological characteristics, treatments, and survival outcomes, were collected from the SEER database between 2000 and 2018. The primary endpoints were overall survival (OS) and cancer-specific survival (CSS). The eligible patients were randomly divided into development cohort and validation cohort in a 7:3 ratio. The nomograms for prediction of OS and CSS were constructed by the development cohort using a LASSO-Cox regression model, respectively. Besides the model performance was internally and externally validated by examining the discrimination, calibration, and clinical utility.

Results

A total of 632 consecutive patients who had been diagnosed with PASC were identified and randomly divided into development (n = 444) and validation (n = 188) cohorts. In the development cohort, the estimated median OS was 7.0 months (95% CI: 6.19-7.82) and the median CSS was 7.0 months (95% CI: 6.15-7.85). In the validation cohort, the estimated median OS was 6.0 months (95% CI: 4.46-7.54) and the median CSS was 7.0 months (95% CI: 6.25-7.75). LASSO-penalized COX regression analysis identified 8 independent predictors in the OS prediction model and 9 independent risk factors in the CSS prediction model: age at diagnosis, gender, year of diagnosis, tumor location, grade, stage, size, lymph node metastasis, combined metastasis, surgery, radiation, and chemotherapy. The Harrell C index and time-dependent AUCs manifested satisfactory discriminative capabilities of the models. Calibration plots showed that both models were well calibrated. Furthermore, decision curves indicated good utility of the nomograms for decision-making.

Conclusion

Nomogram-based models to evaluate personalized OS and CSS in patients with PASC were developed and well validated. These easy-to-use tools will be useful methods to calculate individualized estimate of survival, assist in risk stratification, and aid clinical decision-making.

Application of Unenhanced Computed Tomography Texture Analysis to Differentiate Pancreatic Adenosquamous Carcinoma from Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The objective of this study was to investigate the application of unenhanced computed tomography (CT) texture analysis in differentiating pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC).

METHODS

Preoperative CT images of 112 patients (31 with PASC, 81 with PDAC) were retrospectively reviewed. A total of 396 texture parameters were extracted from AnalysisKit software for further texture analysis. Texture features were selected for the differentiation of PASC and PDAC by the Mann-Whitney U test, univariate logistic regression analysis, and the minimum redundancy maximum relevance algorithm. Furthermore, receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of the texture feature-based model by the random forest (RF) method. Finally, the robustness and reproducibility of the predictive model were assessed by the 10-times leave-group-out cross-validation (LGOCV) method.

RESULTS

In the present study, 10 texture features to differentiate PASC from PDAC were eventually retained for RF model construction after feature selection. The predictive model had a good classification performance in differentiating PASC from PDAC, with the following characteristics: sensitivity, 95.7%; specificity, 92.5%; accuracy, 94.3%; positive predictive value (PPV), 94.3%; negative predictive value (NPV), 94.3%; and area under the ROC curve (AUC), 0.98. Moreover, the predictive model was proved to be robust and reproducible using the 10-times LGOCV algorithm (sensitivity, 90.0%; specificity, 71.3%; accuracy, 76.8%; PPV, 59.0%; NPV, 95.2%; and AUC, 0.80).

CONCLUSION

The unenhanced CT texture analysis has great potential for differentiating PASC from PDAC.

Adenosquamous cancer of the pancreas: A multicenter retrospective study

INTRODUCTION

Adenosquamous cancer of the pancreas (ASCP) is an aggressive, infrequent subtype of pancreatic cancer that combines a glandular and squamous component and is associated with poor survival.

METHODS

Multicenter retrospective observational study carried out at three Spanish hospitals. The study period was: January 2010- August 2020. A descriptive analysis of the data was performed, as well as an analysis of global and disease-free survival using the Kaplan-Meier statistic.

RESULTS

Of a total of 668 pancreatic cancers treated surgically, twelve were ASCP (1.8%). Patient mean age was 69.2±7.4 years. Male/female ratio was 1:1. The main symptom was jaundice (seven patients). Correct preoperative diagnosis was obtained in only two patients. Nine pancreatoduodenectomies and three distal pancreatectosplenectomies were performed. 25% had major complications. Mean tumor size was 48.6±19.4 mm. Nine patients received adjuvant chemotherapy. Median survival time was 5.9 months, and median disease-free survival was 4.6 months. 90% of patients presented recurrence. Ten of the twelve patients in the study (83.3%) died, with disease progression being the cause in eight. Of the two surviving patients, one is disease-free and the other has liver metastases.

CONCLUSION

ASCP is a very rare pancreatic tumor with aggressive behavior. It is rarely diagnosed preoperatively. The best treatment, if feasible, is surgery followed by the standard chemotherapy regimens for pancreatic adenocarcinoma.

Morphological and p40 immunohistochemical analysis of squamous differentiation in endoscopic ultrasound guided fine needle biopsies of pancreatic ductal adenocarcinoma

The basal-like molecular subtype of pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis and upregulation in TP63ΔN (p40) network. Adenosquamous histology can be observed. This study assessed immunohistochemical p40 expression in fine needle biopsy (FNB) samples with PDAC and association with cytomorphological features of squamous differentiation and clinical data. 106 EUS FNBs with PDAC were assessed for eight cytomorphological features of squamous differentiation. P40 H-score (intensity 0-3 × percentage positive nuclei) was analysed for association with morphological features, patient age, gender, operability, chemotherapy and survival. P40 H-score in 14 paired FNBs and resections was compared. P40 h-score was 1-3 in 31%, 4-30 in 16% and > 30 in 13% of FNBs. It was significantly associated with intercellular bridges, elongated cell shape, sharp cell borders, angular nuclei with homogenous chromatin (p < 0.001) and dense cytoplasm (p = 0.002). Keratinisation was not seen. Inoperable patients (n = 81) had a shorter median survival for h-score > 30 (n = 9, 1.8 months) than for h-score ≤ 30 (n = 66, 6.7 months) not quite reaching statistical significance (p = 0.08). P40 was significantly associated with squamous morphology in FNBs with PDAC. P40 H-score > 30 showed a trend towards shorter survival in inoperable patients. Squamous differentiation may be a treatment target in PDAC.

Pancreatic Cancer Microenvironment and Cellular Composition: Current Understandings and Therapeutic Approaches

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal human solid tumors, despite great efforts in improving therapeutics over the past few decades. In PDAC, the distinct characteristic of the tumor microenvironment (TME) is the main barrier for developing effective treatments. PDAC TME is characterized by a dense stroma, cancer-associated fibroblasts, and immune cells populations that crosstalk to the subpopulations of neoplastic cells that include cancer stem cells (CSCs). The heterogeneity in TME is also exhibited in the diversity and dynamics of acellular components, including the Extracellular matrix (ECM), cytokines, growth factors, and secreted ligands to signaling pathways. These contribute to drug resistance, metastasis, and relapse in PDAC. However, clinical trials targeting TME components have often reported unexpected results and still have not benefited patients. The failures in those trials and various efforts to understand the PDAC biology demonstrate the highly heterogeneous and multi-faceted TME compositions and the complexity of their interplay within TME. Hence, further functional and mechanistic insight is needed. In this review, we will present a current understanding of PDAC biology with a focus on the heterogeneity in TME and crosstalk among its components. We also discuss clinical challenges and the arising therapeutic opportunities in PDAC research.

PD-L1 expression and surgical outcomes of adenosquamous carcinoma of the pancreas in a single-centre study of 56 lesions

OBJECTIVE

Adenosquamous carcinoma of the pancreas (ASCP) is a rare histologic subtype of pancreatic carcinoma. The clinicopathologic characteristics and surgical outcomes of ASCP are poorly understood due to the rarity of this disease. Recently, promising clinical responses in patients with pancreatic cancer have been obtained for antibodies against programmed death-1/programmed death-ligand 1 (PD-1/PD-L1). This study investigated the prevalence of PD-L1 expression and surgical outcomes of 56 ASCPs compared to 100 pancreatic ductal adenocarcinomas (PDACs).

METHODS

A total of 56 resected cases of ASCPs were retrospectively reviewed; after matching for the T category, 100 PDACs were selected as a control group for comparison. Immunohistochemistry for p53, Smad4, and PD-L1 was performed in both groups.

RESULTS

The ASCPs exhibited distinct clinicopathologic features, such as larger tumour, location in the distal pancreas, frequent vascular invasion and distant metastasis. In survival analysis, 1-and 2-year overall survival (OS) rates were 51.8% and 17.9%, respectively, with a median follow-up 13 months. According to multivariate analysis, vascular invasion and T category remained independent predictors of OS. Patients with ASCPs showed poorer survival than patients with PDACs after matching for the T category (p = 0.03). p53 and Smad4 were aberrantly expressed in 42 (75%) and 28 (50%) cases, respectively. Under the condition of a 10% cut-off value for PD-L1 positivity, approximately 11% of ASCPs were positive for PD-L1.

CONCLUSIONS

Approximately 11% of patients with ASCPs are assumed to be potential candidates for the application of antibodies against PD-1/PD-L1, as based on the immunohistochemical results for PD-L1.

The role of radiotherapy for pancreatic malignancies: a population-based analysis of the SEER database

Background

To investigate the role of adjuvant radiotherapy in patients with pancreatic cancer.

Methods and patients

The patients with pancreatic cancer from 18 registered institutions in the Surveillance Epidemiology and End Results (SEER) database were retrospectively analyzed. The characteristics of patients who would benefit from adjuvant radiotherapy were screened, as well as whether neoadjuvant or adjuvant radiotherapy conferred to a better clinical outcome. Propensity score matching was used to control for confounding features.

Results

Thirty thousand two hundred and forty-nine patients were included in this study (21,295 vs 8954 in surgery and adjuvant radiotherapy group); 1150 patients were matched in two groups. The median survivals in the surgery (S) group and adjuvant radiotherapy (S + R) group were 24 and 21 months, respectively. The 1-, 3-, and 5-year overall survival (OS) rates in the S group and S + R group were 68%, 40%, 31%, and 75%, 30%, 20%, respectively (p < 0.001), and the median OS was 22 and 25 months in S and S + R group after PSM, the former 1-, 2-, 3-, and 5-year OS were 73%, 45%, 30%, and 19%, and the later were 81%, 52%, 37%, and 24% (p = 0.0015), respectively; stratified analysis showed patients whose carcinoma located at pancreatic head with II stage infiltrating duct carcinoma (22 vs 25, p = 0.0276), T4 adenocarcinoma (28 vs 33, p = 0.0022), N1 stage adenocarcinoma (20 vs 23, p = 0.0203), and patients with infiltrating duct carcinoma received regional resection (23 vs 25, p = 0.028) and number of resected lymph node were ≥ 4 (22 vs 25, p = 0.009) had better OS after additional radiotherapy than surgery alone. Patients with pancreatic body/tail carcinoma III stage adenocarcinoma (13 vs, p = 0.0503) and T4 adenocarcinoma (14 vs, p = 0.0869) had survival advantage within 24 months for additional radiotherapy. However, patients with T2 stage adenocarcinoma located in pancreatic body/tail had better OS in surgery group than that in R + S group.

Conclusions

Additional radiotherapy may contribute to improved prognosis for patients with pancreatic head II stage infiltrating duct carcinoma, III stage adenocarcinoma, T4 stage carcinoma, N1 stage adenocarcinoma, regional resection, or number of lymphadenectomy ≥ 4 in infiltrating duct carcinoma. A specific subgroup of patients with specific stage and histological type pancreatic cancer should be considered for additional radiotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12094-021-02671-0.

Use of ring-enhancement and focal necrosis to differentiate pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma on CT and MRI

PURPOSE

To assess the ability of the ring-enhancing sign and focal necrosis to diagnose adenosquamous carcinoma (ASqC), a variant of pancreatic ductal adenocarcinoma (PDAC), on MRI and CT.

METHODS

The following features of ASqC and conventional PDAC were evaluated on CT and MRI: tumor size, location, margins, borders (non-exophytic, exophytic), and T1 signal intensity. Two readers, blinded to histopathology results, rated their confidence in detecting ring-enhancement and focal necrosis (FN) on a 5-point Likert scale on both MRI and CT. Inter-reader agreement was assessed with Cohen's kappa (k).

RESULTS

A total of 24 patients were included: eight patients with treatment naïve and histologically proven ASqC (six women, mean age: 63, range: 40-75) and 16 patients with PDAC (eight women, mean age: 67, range: 47-83). Statistically significant differences between ASqC and PDAC were seen in tumor size, location, presence of FN, and ring enhancement (p = 0.01-0.037). The readers were more confident in depicting the key differentiating feature ring-enhancement in ASqC on MRI compared to CT (confidence 1.71 ± 0.49 vs. 0.88 ± 0.35, p = 0.017) with moderate inter-reader agreement (k = 0.46 and 0.5, respectively). FN showed substantial inter-reader agreement on MR and moderate agreement on CT (k = 0.67 and 0.5, respectively).

CONCLUSIONS

Compared to CT, MRI depicts ring-enhancement in ASqC with greater reader confidence and FN in ASqC with higher inter-reader agreement. The concurrent presence of these two imaging features should raise high suspicion for ASqC.

[Computed tomography in determining the differentiation of ductal adenocarcinoma of pancreatic head]

OBJECTIVE

To evaluate the features of «hypervascular rim», tumor dimensions and density as prognostic factors of differentiation of pancreatic head adenocarcinoma.

MATERIAL AND METHODS

Pancreatoduodenectomy was performed in 311 patients with pancreatic head adenocarcinoma for the period 2013-2019. A retrospective study included 81 patients who met the following criteria: available data of morphological and immunohistological examination indicating tumor grade from Grade 1 to Grade 3, as well as available preoperative CT images in four phases (native, arterial, portal and delayed). Tumor dimensions, density of the pancreas, adenocarcinoma and abdominal aorta by the phases of contrast enhancement were analyzed in all patients. Moreover, we estimated coefficient of relative enhancement change. Perifocal hypervascular enhancement was assessed in arterial and portal phases. Contrast-enhanced MRI was performed in 15 out of 81 patients. MR images were analyzed regarding a hypervascular rim, and the last one was compared with CT images.

RESULTS

There was no significant difference in density values between different tumor grades. Coefficient of relative enhancement change >1 was observed in 63.64% of highly-differentiated tumors. REC ≤1 was found in 85.11% of tumors grade 2 and 82.6% of tumors grade 3 (p=0.005). According to Chi-square test, there was a correlation between tumor differentiation and hypervascular rim (p=0.03). Moderate and low differentiation was observed in 96.42% of tumors with perifocal enhancement. Hypervascular rim was absent in 81.82% of tumors grade 1. Adenocarcinoma grade 2 was found in 85.71% of cases with unclear perifocal enhancement.

CONCLUSION

Preoperative contrast-enhanced CT is valuable to assume the tumor grade in patients with pancreatic head adenocarcinoma due to assessment of hypervascular rim and REC.