Adenosquamous versus adenocarcinoma of the pancreas: a population-based outcomes analysis

A case of pancreatic adenosquamous cell carcinoma with a pseudocyst following curative surgery

BACKGROUND

Pancreatic adenosquamous cell carcinoma (PASC) is a relatively rare histological type of pancreatic malignancy, and preoperative diagnosis is difficult because of its rarity. PASC accounts for 1-4% of all pancreatic cancers, and even after curative surgery, its prognosis is poorer than that of ordinary pancreatic adenocarcinoma. Pathologically, it shows glandular and squamous differentiation of cells. Complete resection is the only method to achieve a good long-term prognosis, and an increasing doubling time of PASC is considered to indicate early recurrence after surgery. Here, we report a rare case of PASC with an infected pancreatic cyst that was difficult to treat, along with a review of the literature.

CASE PRESENTATION

A woman in her 80s with a history of breast cancer presented with pericardial pain. Computed tomography revealed a 20-mm hypovascular tumor in the body of the pancreas and a 27-mm pseudocyst. Endoscopic retrograde cholangiopancreatography showed a severe main pancreatic duct stenosis in the body of the pancreas that made cannulation impossible, and contrast media extravasation was due to pancreatic duct disruption in the pancreatic tail. Endoscopic fine-needle aspiration revealed that the tumor was a PASC. Because the patient had an infected pancreatic cyst, central intravenous nutrition and antibiotics were administered, which stabilized her general condition. She was diagnosed with resectable PASC and underwent distal pancreatectomy with lymphadenectomy. The postoperative course was uneventful. Immunohistochemical analysis of the resected specimen confirmed T2N0M0 stage IB. Systemic adjuvant chemotherapy with S-1 is ongoing.

CONCLUSION

Appropriate preoperative management and preoperative accurate staging (T2N0M0 stage IB) of PASC with curative surgery can ensure predictable outcomes.

Advanced Adenosquamous Carcinoma of the Ampulla of Vater Treated with Adjuvant Chemotherapy after Pancreaticoduodenectomy

Introduction

Adenosquamous carcinoma (ASC) of the ampulla of Vater (AmV) is rare. The prognosis is generally worse in patients undergoing resection of ASC of the AmV than in those undergoing resection of adenocarcinoma of the AmV because the former shows early recurrence after surgery. A treatment strategy for ASC of the AmV has not been established, and the efficacy of adjuvant chemotherapy after curative resection is unclear. Given the paucity of data, we report a case of ASC of the AmV that was curatively resected and treated with adjuvant chemotherapy.

Case Presentation

A 66-year-old man presented with pruritus and anorexia. Contrast-enhanced computed tomography revealed a tumor measuring 1.6 cm in diameter located at the AmV and distal bile duct. Biopsy revealed adenocarcinoma of the AmV. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. Histopathological examination contradictorily revealed ASC of the AmV and lymph node metastases. The postoperative course of the patient was uneventful, and he was discharged on day 25. The patient underwent S-1 adjuvant chemotherapy for 6 months and did not exhibit any postoperative recurrence for a follow-up duration of 28 months.

Conclusion

Although treatment strategy for ASC of the AmV has not been established, our case shows that surgery followed by S-1 adjuvant chemotherapy could improve prognosis of patients with such tumors. However, further research is required to determine the efficacy of adjuvant chemotherapy and treatment strategies for resectable ASC of the AmV.

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.

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.

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.

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.

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.

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.

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.

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.

Clinical presentation and prognosis of adenosquamous carcinoma of the pancreas - Matched-pair analysis with pancreatic ductal adenocarcinoma

INTRODUCTION

Adenosquamous carcinoma of the pancreas (ASCP) is a rare subtype of pancreatic adenocarcinoma. The aim of this study was to investigate the characteristics and outcomes of ASCP in comparison to pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

All patients with ASCP treated between December 2001 and December 2017 were identified from a prospective database. Clinicopathological and follow-up data were analyzed. A nested case-control-study with matched-pair analysis was performed to compare overall survival of ASCP and PDAC.

RESULTS

Of 4009 patients undergoing surgery for pancreatic adenocarcinoma 91 patients had ASCP. Compared to PDAC ASCP were larger (4.0 vs. 3.2 cm; p < 0.0001), more frequently involved lymph nodes (88% vs. 78%; p = 0.0216), more frequently showed poor differentiation (G3: 79% vs. 36%; p < 0.0001) and more frequently were located in the pancreatic tail (19% vs. 10%; p = 0.0179). Overall median post-resection-survival was shorter in ASCP (10.8 vs. 20.5 months in PDAC; p = 0.0085), but 5-year survival rates were comparable (18.2% vs. 17.5%). After matching for the unevenly distributed prognostic factors survival after resection of ASCP and PDAC was comparable (p = 0.8301). Localization in the head or several parts of the pancreas, high CA 19-9 levels, and M1 disease were independent predictors of survival in patients with ASCP.

CONCLUSION

ASCP is more aggressive with poorer differentiation and higher rates of lymph node metastases compared to PDAC. In spite of a shorter median survival, 5-year survival rates after surgical resection of about 18% can be expected in ASCP and support resection as part of a multimodal therapy as the treatment of choice in this rare cancer.

Prognostic Analysis and Influencing Serum Biomarkers of Patients With Resectable Pancreatic Adenosquamous Cancer

Objectives

There are few reports about the survival rate of patients with pancreatic adenosquamous cancer (PASC). This study evaluated and analyzed prognostic factors of patients with resectable pancreatic adenosquamous cancer (rPASC), which might fulfill the blank in the research of PASC.

Methods

In this study, we identified and analyzed 55 patients who were diagnosed with rPASC from January 2013 to May 2019 at the Pancreatic Disease Center of the Shanghai Ruijin Hospital affiliated with Shanghai Jiaotong University School of Medicine. Age, sex, BMI, tumor position, and other important demographic data were collected and analyzed. The follow-up was updated by December 31th, 2019 with a median follow-up of nine months.

Results

Among the 55 patients, 23 (41.8%) patients were female, and the mean age was 62.0 ± 10.3 years. The median overall survival (OS) time was 10 ± 2.1 months, and the median disease-free survival (DFS) time was 4 ± 0.9 months. The 1-year, 3-year, and 5-year survival rates were 40.9, 17.5, and 11.6%, respectively. The multivariate analysis showed that normal serum level of Ca199 (HR = 0.464, 95% CI = 0.222–0.970, P = 0.041) and Ca125 (HR = 0.441, 95% CI = 0.233–0.835, P = 0.012) were independent favorable prognostic factors.

Conclusion

Patients with rPASC had poor survival. The 5-year survival rate was only 11.6%. Normal serum levels of Ca199 and Ca125 were independent favorable prognostic factors that predicted prognosis.

The importance of multimodal therapy in the management of nonmetastatic adenosquamous carcinoma of the pancreas: Analysis of treatment sequence and strategy

BACKGROUND

Adenosquamous carcinoma of the pancreas has historically poor survival. We analyzed survival outcomes stratified by treatment regimen and sequence using an administrative dataset.

METHODS

Adult patients with nonmetastatic adenosquamous carcinoma of the pancreas were identified using the National Cancer Database (2010-2016). Multivariable analyses were used to determine factors associated with receipt of neoadjuvant or adjuvant chemotherapy. Overall survival was estimated by Kaplan-Meier analysis and a multivariable Cox model was used to evaluate factors associated with survival.

RESULTS

A total of 838 patients with adenosquamous carcinoma of the pancreas were included in the analysis. The median age was 69 years and 64.7% of patients underwent pancreatectomy. Among patients who underwent pancreatectomy, 60.5% received adjuvant chemotherapy, 14.8% received neoadjuvant chemotherapy, and 24.7% underwent surgery alone. Older age and increasing comorbidity index were associated with a reduced likelihood of receiving neoadjuvant or adjuvant chemotherapy. Median survival of patients who received chemotherapy alone was similar compared with patients who underwent pancreatectomy alone (9.2 vs 7.2 months, P = .504). Survival was improved if patients received both chemotherapy and pancreatectomy (neoadjuvant = 19.6 months, hazard ratio = 0.58; adjuvant = 19.4 months, hazard ratio = 0.64) compared with pancreatectomy alone.

CONCLUSION

Patients with adenosquamous carcinoma of the pancreas who do not receive multimodal therapy have poor survival. The sequence of chemotherapy and pancreatectomy is not associated with survival, but 25% of patients who undergo surgery do not receive chemotherapy. Given that there is no difference in median survival between patients who undergo pancreatectomy alone or receive chemotherapy alone, our data question whether neoadjuvant chemotherapy should be considered in patients with potentially resectable adenosquamous carcinoma of the pancreas.

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.

Identification of germline and somatic mutations in pancreatic adenosquamous carcinoma using whole exome sequencing

OBJECTIVES

Pancreatic cancer is one of the most lethal malignancies worldwide. Pancreatic adenosquamous carcinoma (PASC) is a rare histological type of pancreatic carcinoma with a poor prognosis. The median survival time after diagnosis is less than one year. It is believed that the pathogenesis of PASC is different from pancreatic adenocarcinoma. In this study, we tried to reveal the intrinsic gene mutations associated with PASC through whole exome sequencing.

METHODS

Both cancerous and paracancerous tissues were collected from 12 pathologically diagnosed PASC patients. Their clinical characteristics were collected, and patient survival information was obtained through follow-up. The correlations between the mutations and clinical characteristics were analysed.

RESULTS

Germline mutations were identified in MAP3K1 (9 cases), PDE4DIP (7), BCR (7), ALK (6), USP6 (5), AR (4), HLA-A (4), SPEN (4), KMT2D (3), NUTM2B (3), ZFHX3 (3), and MN1 (3), while somatic mutations were found in TP53 (5), KRAS (3), HRNR (3), and OBSCN (3). Peripheral tissue invasion was associated with somatic mutations in KRAS (P= 0.0339). Additionally, there were significant correlations between lymphatic metastasis and germline mutations in USP6 (P= 0.0228) and somatic mutations in OBSCN and HRNR (P= 0.0339).

CONCLUSION

In conclusion, susceptibility genes including MAP3K1, PDE4DIP, and BCR are frequently found to be mutated in the germlines of PASC patients. Somatic mutations in KRAS, OBSCN, and HRNR and germline mutations in USP6 are related to tumour invasion and metastasis, reinforcing the necessity of translating these potential biomarkers into clinical practice.

Adenosquamous carcinoma of the digestive system: a literature review

Adenosquamous carcinoma (ASC), containing both adenocarcinoma and squamous cell carcinoma components, is rare in the digestive system. Limited data is available on ASC of the digestive system (AS-ASC), and the current evidence is available mainly in the form of case reports and case series. We performed a thorough search of the available literature and compiled a review on the epidemiology, histopathology, pathogenesis, clinical manifestations, diagnosis, treatment, and prognosis of AS-ASC. Non-specific clinical and imaging presentations and low diagnostic accuracy of biopsy lead to difficulties in preoperative diagnosis in a high proportion of patients and high malignancy. The pathogenesis remains obscure. Surgery remains the mainstay of treatment for AS-ASC. The role of chemoradiotherapy as an adjuvant treatment is still inconclusive. Key messages Metastatic linings and the lack of efficacious treatments lead to an unfavorable outcome in AS-ASC patients. Further research could help us understand the pathophysiology of AS-ASCand the unique needs of AS-ASC patients.

Increased proportion of the squamous cell carcinoma component is associated with worse survival in resected gastric adenosquamous carcinoma: A STROBE compliant cohort study

For the diagnosis of gastric adenosquamous carcinoma (ASC), discrepancies regarding a rational diagnostic proportion of the squamous cell carcinoma (SCC) component exist among different organizations. Our study aimed to evaluate the impact of the SCC component on the survival of gastric cancer patients and identify the optimal cutoff value for the SCC component necessary for diagnosing gastric ASC.Cases of gastric cancer with an SCC component were obtained from our center and from case reports and series extracted from Medline. Univariate and multivariate analyses were conducted to compare the overall survival between groups and examine the prognostic value of various clinical parameters.We identified 45 qualified cases in published literature and 13 in our center. Forty-two of them were males and 16 females (M: F = 2.6:1). Thirty of them were Asian patients and the rest were mainly from the United States and Europe. The mean age was 61.1 years (median 64 years, range 32-84 years). The average tumor size was 6.9 cm (median 6.0 cm, range 2.0-16.0 cm). The most common location of the cancer was the lower third (39.7%). Although a statistical difference was not achieved, the Kaplan-Meier curve demonstrated that as the proportion of the SCC component in the primary lesion increased, the patients' survival risk increased (P = .489), and the presence of the SCC component in metastatic lymph nodes also increased the risk of survival (P = .259); both of these findings indicated a negative impact of the SCC component on survival. Furthermore, we identified the optimal cutoff for the SCC component as 35% (χ = 6.544, P = .011), which was subsequently validated in a Cox regression model as an independent prognostic factor (P = .026).An increased proportion of the SCC component is associated with worse survival in gastric cancer patients with an SCC component. The optimal cutoff for the proportion of the SCC component necessary for the diagnosis of gastric ASC is 35%.

Pancreatic Ductal Adenocarcinoma and Its Variants: Pearls and Perils

Pancreatic ductal adenocarcinoma (PDAC), an epithelial neoplasm derived from the pancreatic ductal tree, is the most common histologic type of pancreatic cancer and accounts for 85%-95% of all solid pancreatic tumors. As a highly lethal malignancy, it is the seventh leading cause of cancer death worldwide and is responsible for more than 300 000 deaths per year. PDAC is highly resistant to current therapies, affording patients a 5-year overall survival rate of only 7.2%. It is characterized histologically by its highly desmoplastic stroma embedding tubular and ductlike structures. On images, it typically manifests as a poorly defined hypoenhancing mass, causing ductal obstruction and vascular involvement. Little is known about the other histologic subtypes of PDAC, mainly because of their rarity and lack of specific patterns of disease manifestation. According to the World Health Organization, these variants include adenosquamous carcinoma, colloid carcinoma, hepatoid carcinoma, medullary carcinoma, signet ring cell carcinoma, undifferentiated carcinoma with osteoclast-like giant cells, and undifferentiated carcinoma. Depending on the subtype, they can confer a better or even worse prognosis than that of conventional PDAC. Thus, awareness of the existence and differentiation of these variants on the basis of imaging and histopathologic characteristics is crucial to guide clinical decision making for optimal treatment and patient management.

Adenosquamous Carcinoma of the Pancreas Comprise a Heterogeneous Group of Tumors With the Worst Outcome: A Clinicopathological Analysis of 25 Cases Identified in 562 Pancreatic Carcinomas Resected With Curative Intent

OBJECTIVES

Information of the clinicopathological characteristics and outcome data of patients with adenosquamous carcinoma of the pancreas (ASCAP) remains limited. This study's aim is to describe the clinical, pathological, and molecular characteristics of 25 resected ASCAPs.

METHODS

Of all 25 cases, patient characteristics, follow-up data, and pathological/immunohistological features were reviewed and analyzed.

RESULTS

In this 3-institutional retrospective analysis of 562 pancreatic cancer patients, we identified 25 cases with histologically confirmed ASCAP (4.4%). Follow-up was available in 21 ASCAP and 50 pancreatic ductal adenocarcinoma control patients with a median overall survival of 8.2 and 21 months, respectively. Age, tumor size, localization in the tail, lymph node status, and resection margin seem to be the most significant factors of survival in our ASCAP cohort. In contrast to pancreatic ductal adenocarcinoma, positive expression of p63, keratins K5/14, and the epidermal growth factor receptor are a robust marker profile of these tumors.

CONCLUSIONS

Adenosquamous carcinoma of the pancreas comprises a group of neoplasms in which stage and adverse morphological features contribute to its bad prognosis. Further work must be pursued to improve detection and treatment options to reduce mortality. Specifically, differences in biology might become a target for the development of possible therapies.

Cellular organization and histogenesis of adenosquamous carcinoma of the pancreas: evidence supporting the squamous metaplasia concept

Adenosquamous carcinoma of the pancreas (ASCAP) is characterized by conventional pancreatic ductal adenocarcinoma (PDAC) and squamous carcinoma components with at least 30% of the tumour showing squamous differentiation. To get further insight into the histogenesis of these lesions, we analysed the cellular organization of ASCAP compared to PDACs. Using Immunohistochemistry and triple immunofluorescence labelling studies for keratins, p63, p40, MUC1, MUC2, MUC5AC, Ki67, and EGFR we demonstrate that many ASCAPs contain a transitional zone between the K8/18-positive adenocarcinomatous component and the p63+ /p40+ /K5/K14+ squamous component initiated by the expression of p63 in K8/18+ adenocarcinomatous cells and the appearance of basally located p63+ K5/14+ cells. p63+ K5/14+ cells give rise to fully developed squamous differentiation. Notably, 25% of conventional PDACs without histologically recognizable squamous component contain foci of p63+ p40+ and K5/14+ cells similar to the transitional zone. Our data provide evidence that the squamous carcinoma components of ASCAPs originate from pre-existing PDAC via transdifferentiation of keratin K8/18-positive glandular cells to p63-, p40-, and keratin K5/14-positive squamous carcinoma cells supporting the squamous metaplasia hypothesis. Thus our findings provide new evidence about the cellular process behind squamous differentiation in ASCAPs.

Early relapse on adjuvant gemcitabine associated with an exceptional response to 2nd line capecitabine chemotherapy in a patient with pancreatic adenosquamous carcinoma with strong intra-tumoural expression of cytidine deaminase: a case report

BACKGROUND

Pancreatic adenosquamous carcinoma has a poor prognosis, with limited prospective trial data to guide optimal treatment. The potential impact of drug metabolism on the treatment response of patients with pancreatic adenosquamous carcinoma is largely unknown.

CASE PRESENTATION

We describe the case of a 51 year old woman with pancreatic adenosquamous carcinoma who, following surgical resection, experienced early disease relapse during adjuvant gemcitabine therapy. Paradoxically, this was followed by an exceptional response to capecitabine therapy lasting 34.6 months. Strong expression of cytidine deaminase was detected within the tumour.

CONCLUSIONS

This case study demonstrates that early relapse during adjuvant chemotherapy for pancreatic adenosquamous carcinoma may be compatible with a subsequent exceptional response to second line chemotherapy, an important observation given the poor overall prognosis of patients with adenosquamous carcinoma. Cytidine deaminase is predicted to inactivate gemcitabine and, conversely, catalyze capecitabine activation. We discuss strong intra-tumoural expression of cytidine deaminase as a potential mechanism to explain this patient's disparate responses to gemcitabine and capecitabine therapy, and highlight the benefit that may be gained from considering similar determinants of response to chemotherapy in clinical practice.

Adenosquamous Carcinoma of the Pancreas

A 60-year-old woman presented to hospital with abdominal pain and massive weight loss. Imaging studies confirmed the presence of a tumor of the pancreas. Histologic analysis of the sampling performed by echoendoscopic ultrasound fine-needle aspiration found aspects evocative of adenosquamous carcinoma. This case report highlights the difficulties of clinical pathologic diagnosis for these occasionally composite tumors. The patient underwent palliative chemotherapy based on platinum and 5-fluorouracil, followed by second-line chemotherapy with FOLFIRI after progression. Adenosquamous carcinoma of the pancreas remains a rare tumor with very poor prognosis and limited therapeutic options.

Chemoradiotherapy is associated with improved survival for resected pancreatic adenosquamous carcinoma: a retrospective cohort study from the SEER database

Background

The prognosis of pancreatic adenosquamous carcinoma (PASC) after surgery is poor. The purpose of this study was to clarify the prognostic factors of PASC and evaluate the efficacy of combination chemoradiotherapy.

Methods

The patients' data retrieved from the Surveillance, Epidemiology, and End Results database (SEER) between 2004 and 2015 were stratified and analyzed in this study. The univariate and multivariate analysis were used for overall survival (OS) and cancer-specific survival (CSS).

Results

T staging, M staging, chemotherapy and radiotherapy is the independent prognostic indicator after PASC resection for both OS and CSS. In the total cohort, 44 patients had both chemo and radiotherapy, with median OS 23 months and CSS 29 months, which was significantly better than neither chemo nor radiotherapy group (68 patients, median OS 8 months and CSS 11 months), and either chemotherapy or radiotherapy group (91 patients, median OS 13 months and CSS 15 months). The survival benefit of chemoradiotherapy was validated in the specific group (n=159) who had only primary PASC. PASC patients receiving chemoradiotherapy had longer OS and CSS than those with neither chemo nor radiotherapy in TNM stage I, II and IV subgroups.

Conclusions

The chemoradiotherapy revealed its prognostic superiority in PASC treatment.

CT and MR imaging features of pancreatic adenosquamous carcinoma and their correlation with prognosis

PURPOSE

To retrospectively investigate the computed tomography (CT) and magnetic resonance (MR) imaging features of pancreatic adenosquamous carcinoma (PASC) and the association between imaging findings and prognosis.

MATERIALS AND METHODS

CT, MR images of 26 patients with PASC were analyzed. Clinical symptoms, tumor markers, and patients' survival were recorded. Tumor attenuation, enhancement pattern and degree, vessel involvement, adjacent tissue invasion and metastasis were evaluated. The association between imaging features and overall survival (OS) were also assessed using Cox proportional hazards ratio model.

RESULTS

Fourteen masses were found in the head of the pancreas and 12 in the body/tail. The mean tumor size was 4.47 ± 1.76 cm. PASC usually showed ill-defined (96.2%), lobulated (76.9%) and predominantly solid mass (92.3%). Ring enhancement in the peripheral area of the tumor was commonly seen (76.9%). Vessel invasion was seen in 17 cases (65.4%), encasement of adjacent arteries in 7 cases (26.9%), upstream main pancreatic duct (MPD) dilatation in 16 cases (61.5%) and double duct sign in 9 cases (34.6%). Multivariate Cox proportional hazards model demonstrated that patients with vessel invasion may predict a poor prognosis (p = 0.037).

CONCLUSION

PASC tends to be an ill-defined solid mass with peripheral ring enhancement, and relatively poor enhancement in the central area. PASC may also show vessel invasion, vessel encasement and upstream MPD dilatation. Vessel invasion may indicate a poor prognosis.

110 Patients with adenosquamous carcinomas of the pancreas (PASC): imaging differentiation of small (≤ 3 cm) versus large (> 3 cm) tumors

OBJECTIVE

This study examined radiological imaging features of small (≤ 3 cm) and large (> 3 cm) adenosquamous carcinomas of the pancreas (PASC) lesions to better understand the morphology of these lesions.

METHODS

Images from 110 patients with pathologically proven PASC (80 males and 30 females, mean age: 62.6 years) were retrospectively reviewed. Two radiologists analyzed images and reached a consensus regarding the following features: location, shape, margins, presence of solid and necrotic components, rim enhancement, density/intensity during the portal venous phase, invasion of surrounding organs, vascular invasion, venous tumor thrombus formation, and enlarged lymph nodes. Differences in the imaging features between the two groups were evaluated with the Chi-square test or Fisher's exact test.

RESULTS

There were 41 small PASC lesions (mean age: 60.59 years) and 69 large PASC lesions (63.74 years). Statistical analysis demonstrated significant differences in the location, shape, adjacent organ and vessel invasion, and venous tumor thrombus formation (P < 0.05). Small PASC lesions were more frequently detected in the pancreatic head and had an ovoid shape. There was no significant difference in the presence of solid and necrotic components (P = 0.090), including approximately 3/4 of the lesions with necrosis and 1/4 purely solid lesions, enlarged lymph nodes (P = 0.068) and other features.

CONCLUSION

Regardless of the tumor size, 75% of PASC lesions present with central necrosis while 25% are purely solid. Small PASC lesions can be associated with lymph node metastasis at a relatively early stage. Large PASC lesions are likely to invade adjacent tissues and be associated with venous tumor thrombus formation.

Two rare cases of pancreatic adenosquamous carcinoma: A review of the literature with focus on radiologic findings

Pancreatic adenosquamous carcinoma (PASC) is a rare, aggressive subtype of pancreatic tumor with a poor prognostic outlook compared to the much more common pancreatic adenocarcinoma. Here we present two cases of the rare PASC and analyze the radiologic findings on computed tomography (CT) and 18F- fluorodeoxyglucose positron emission tomography (FDG-PET).

Both cases involve 62-year-old women presenting with abdominal pain, nausea, and vomiting who on imaging were found to have infiltrating lobular pancreatic masses with ring enhancement on CT and peripheral hypermetabolism with central necrosis on FDG-PET. Location in the pancreas and involvement of adjacent structures differed in the two cases, resulting in varying progressive clinical manifestations.

PASC is a rare subtype of pancreatic cancer with nonspecific imaging findings. Here we presented two cases of PASC supporting previously reported imaging findings suggestive of PASC with additional FDG-PET manifestations and SUV levels, which only few reports have previously described.

Long-term outcomes after an aggressive resection of adenosquamous carcinoma of the pancreas

PURPOSE

Adenosquamous carcinoma (ASC) of the pancreas is a rare malignancy, associated with a poor prognosis after surgical resection, with reported median survival times (MSTs) ranging from 4.4 to 13.1 months. We conducted this study to investigate the long-term outcomes of patients after the resection for ASC.

METHODS

Between 2002 and 2016, a total of 456 patients underwent resection for ASC or adenocarcinoma (AC) of the pancreas. ASC was confirmed in 17 (3.7%) of these patients. We analyzed the clinicopathological characteristics and survival of these 17 patients in comparison with those of patients with AC of the pancreas.

RESULTS

The operative procedures performed were pancreaticoduodenectomy (n = 6) and distal pancreatectomy (n = 11). Seven (41.2%) of the 17 patients underwent combined organ resection. R0 resection was achieved in 16 (94.1%) patients. The 5-year overall survival (OS) rate and MST were 40.3% and 20.9 months, respectively. A squamous component of ≥ 60% (P = 0.001) and R1 resection (P < 0.001) were significantly associated with poor OS for patients with ASC CONCLUSION: This study revealed longer survival and a higher R0 resection rate after aggressive combined resection in our ASC patients than those in previous studies. Although this was only a small series, our findings suggest that local control with aggressive resection may be an effective treatment protocol for ASC patients.

Cyclooxygenase-2 Influences Response to Cotargeting of MEK and CDK4/6 in a Subpopulation of Pancreatic Cancers

The ineffectiveness of chemotherapy in patients with pancreatic cancer highlights a critical unmet need in pancreatic cancer therapy. Two commonly mutated genes in pancreatic cancer, KRAS and CDKN2A, have an incidence exceeding 90%, supporting investigation of dual targeting of MEK and CDK4/6 as a potential therapeutic strategy for this patient population. An in vitro proliferation synergy screen was conducted to evaluate response of a panel of high passage and patient-derived pancreatic cancer models to the combination of trametinib and palbociclib to inhibit MEK and CDK4/6, respectively. Two adenosquamous carcinoma models, L3.6pl and UM59, stood out for their high synergy response. In vivo studies confirmed that this combination treatment approach was highly effective in subcutaneously implanted L3.6pl and UM59 tumor-bearing animals. Both models were refractory to single-agent treatment. Reverse-phase protein array analysis of L3.6pl tumors excised from treated animals revealed strong downregulation of COX-2 expression in response to combination treatment. Expression of COX-2 under a CMV-driven promoter and shRNA knockdown of COX-2 both led to resistance to combination treatment. Our findings suggest that COX-2 may be involved in the improved therapeutic outcome seen in some pancreatic tumors that fail to respond to MEK or CDK4/6 inhibitors alone but respond favorably to their combination.

Comparative outcomes of adenosquamous carcinoma of the pancreas: An analysis of the National Cancer Database

BACKGROUND

A paucity of data exists regarding the natural history and outcome measures of adenosquamous carcinoma of the pancreas (ASCP), a histology distinct from pancreatic adenocarcinoma (PDAC). The aim of this study is to characterize the clinicopathological features of ASCP in a large cohort of patients comparing outcome measures of surgically resected patients to PDAC.

METHODS

We identified patients diagnosed with ASCP or PDAC from the National Cancer Database from 2004 to 2012. Patient demographics, tumor characteristics, treatment regimens, and overall survival were analyzed between the groups.

RESULTS

We identified 207 073 patients: 205 328 (99%) in the PDAC group and 1745 (1%) in the ASCP group. ASCP tumors were larger, located more frequently in a body/tail location (36% vs 24%, P < 0.001), undifferentiated/anaplastic histology (41% vs 17%, P < 0.001), and early stage presentation, (39% vs 32%, P < 0.001). There was no significant difference in OS when comparing all patients with PDAC and ASCP (6.2 months and 5.7 months, P = 0.601). In surgical patients ASCP histology was associated with worse OS (14.8 months vs 20.5 months, P < 0.001) but had lower nodal involvement (55% vs 61%, P < 0.001). ASCP histology was independently associated with worse OS, after adjusting for tumor characteristics, treatment, and patient demographics. In patients with only resected ASCP histology, negative lymph node status, R0 surgical resection, and receipt of chemotherapy was independently associated with improved overall survival following surgical resection.

CONCLUSION

Although patients with ASCP and PDAC tumors have similar survival when non-surgical and surgical patients are combined, ASCP is associated with worse survival in stage I/II resected patients.

Rare Tumors and Lesions of the Pancreas

There are a few entities that account for most solid and cystic masses of the pancreas. The pancreas harbors a wide array of diseases, including adenocarcinoma, and its variants, such as anaplastic and adenosquamous carcinoma. Other neoplasms include acinar cell carcinoma, solid pseudopapillary tumor, and sarcomas. Benign lesions include hamartomas, hemangiomas, lymphangioma, and plasmacytoma. Isolated metastases include renal cell carcinoma, melanoma, and other carcinomas. Benign inflammatory conditions, such as autoimmune pancreatitis and groove pancreatitis can also mimic solid neoplasms of the pancreas.

Clinical implications of the proliferative ability of the squamous component regarding tumor progression of adenosquamous carcinoma of the pancreas: A preliminary report

OBJECTIVES

The objectives of this study were to examine the clinicopathological characteristics of patients with adenosquamous carcinoma of the pancreas (ASCP) and assess whether the proliferative ability of the squamous cell carcinoma (SCC) component contributes to either its proportion within the tumor or tumor progression.

METHODS

We retrospectively reviewed 12 patients with resected ASCP and compared their clinicopathological characteristics with those of 161 patients with adenocarcinoma of the pancreas (ACP). The Ki-67 indexes of the separate ASCP components were assessed.

RESULTS

All the clinicopathological characteristics and outcomes were similar between the ASCP patients and ACP patients. Among the 12 ASCP cases, nine exhibited higher Ki-67 levels in the SCC component than in the corresponding adenocarcinoma (AC) component at primary sites (P = 0.022). The component with a higher Ki-67 level coincided with the predominant component at the primary site in nine of 11 patients. In all 10 patients who presented lymph node metastasis, the metastases almost entirely consisted of either the SCC or AC component. The SCC component was absent from metastatic lymph nodes in five of 10 patients even though the Ki-67 levels at the primary site in four of these patients were higher in the SCC component than in the AC component.

CONCLUSIONS

The enhanced proliferative ability of the SCC component of ASCP is reflected by its proportion within the tumor. However, other biological factors might contribute to metastasis in ASCP.

Pancreatic Squamous Cell Carcinoma: A Population-Based Study of Epidemiology, Clinicopathologic Characteristics and Outcomes

OBJECTIVES

Squamous metaplasia is commonly detected in pancreatic parenchyma; however, primary pancreatic squamous cell carcinoma (SCC) is a rare malignancy with unknown incidence and unclear prognosis.

METHODS

Surveillance, Epidemiology, and End Results (SEER) registries were examined identifying pancreatic SCC and adenocarcinoma cases from 2000 to 2012. Age-adjusted incidence rates were calculated. Patients with SCC versus adenocarcinoma were compared by clinical features and relative survival outcomes.

RESULTS

We identified 214 patients with SCC and 72,860 with adenocarcinoma. For SCC, incidence rates tripled between 2000 and 2012. Significantly higher SCC incidence rates were observed in older age groups, blacks, and males. Greater proportion of patients with SCC than those with adenocarcinoma had poorly differentiated histology (73.0% vs 43.7%, P < 0.001). In both subtypes, majority of patients had stage IV disease, 59.0% for adenocarcinoma versus 62.6% for SCC. The 1- and 2-year relative survival rate was significantly lower in patients with SCC versus adenocarcinoma. The 1-year relative survival was 14.0% (95% confidence interval, 9.5%-19.4%) for SCC, compared with 24.5% (95% confidence interval, 24.2%-24.8%) for adenocarcinoma.

CONCLUSIONS

Although primary pancreatic SCC is a rare neoplasm, incidence rates for this subtype are increasing. Relative to adenocarcinoma, pancreatic SCC is characterized by poorly differentiated histology and worse survival.

Adenosquamous Carcinoma of the Pancreas in a Patient with BRCA2 Mutation: A Case Report

Background: Pancreatic adenosquamous carcinoma (ASC) is an uncommon subtype of pancreatic neoplasm, representing 1–4% of all pancreatic cancers. Given the rarity of this tumor, there is no well-established standard of care regarding treatment. We present the case of a BRCA2-deficient patient who responded tremendously well to a combination of gemcitabine and cisplatin therapy.

Case presentation: A 66-year-old Caucasian man presented with a 2-week duration of progressively worsening clay-colored stools, tea-colored urine, and jaundice. Computed tomography scan of the abdomen revealed a 4-cm mass at the head of the pancreas. Preoperative carbohydrate antigen (CA) 19-9 was 255 U/mL (normal <37 U/mL). The patient underwent an uncomplicated pylorus-preserving pancreaticoduodenectomy with pathology revealing 11/12 positive lymph nodes, positive resection margins, perineural invasion, lymphovascular invasion, and positive disease in two distant perihepatic lymph nodes. The patient received one cycle of combination of gemcitabine and abraxane, was subsequently found to be BRCA2 deficient, and completed five cycles of gemcitabine and cisplatin thereafter. CA 19-9 before chemotherapy was 203 U/mL. Postchemotherapy CA 19-9 was 13 U/mL. As of today, the patient continues to do well 22 months postresection without radiographical or gross evidence of disease.

Conclusion: Gemcitabine in combination with a platinum agent shows promise in the treatment of pancreatic ASC, particularly in setting of BRCA2 deficiency.

Adenosquamous carcinoma of the pancreas: Molecular characterization of 23 patients along with a literature review

Adenosquamous carcinoma of the pancreas (ASCP) is a rare entity. Like adenocarcinoma of the pancreas, overall survival is poor. Characteristics of ASCP include central tumor necrosis, along with osteoclasts and hypercalcemia. Various theories exist as to why this histological subtype exists, as normal pancreas tissue has no benign squamous epithelium. Due to the rarity of this disease, limited molecular analysis has been performed, and those reports indicate unique molecular features of ASCP. In this paper, we characterize 23 patients diagnosed with ASCP through molecular profiling using immunohistochemistry staining, fluorescent in situ hybridization, chromogenic in situ hybridization, and gene sequencing, Additionally, we provide a comprehensive literature review of what is known to date of ASCP. Molecular characterization revealed overexpression in MRP1 (80%), MGMT (79%), TOP2A (75), RRM1 (42%), TOPO1 (42%), PTEN (45%), CMET (40%), and C-KIT (10%) among others. One hundred percent of samples tested were positive for KRAS mutations. This analysis shows heretofore unsuspected leads to be considered for treatments of this rare type of exocrine pancreas cancer. Molecular profiling may be appropriate to provide maximum information regarding the patient’s tumor. Further work should be pursued to better characterize this disease.

Efficacy of platinum chemotherapy agents in the adjuvant setting for adenosquamous carcinoma of the pancreas

BACKGROUND

Pancreatic adenosquamous carcinoma (PASC) accounts for only 1-4% of all exocrine pancreatic cancers and carries a particularly poor prognosis. This retrospective study was performed to determine whether inclusion of a platinum agent as part of adjuvant therapy is associated with improved survival in patients with resected PASC.

METHODS

Records of all patients who underwent pancreatic resection at Johns Hopkins Hospital from 1986 to 2012 were reviewed to identify those with PASC. Multivariable Cox proportional hazards modeling was used to assess for significant associations between patient characteristics and survival.

RESULTS

In total, 62 patients (1.1%) with resected PASC were identified among 5,627 cases. Median age was 68 [interquartile range (IQR), 57-77] and 44% were female. Multivariate analysis revealed that, among all patients (n=62), the following factors were independently predictive of poor survival: lack of adjuvant therapy [hazard ratio (HR) =3.6; 95% confidence interval (CI), 1.8-7.0; P<0.001], margin-positive resection (HR =3.5; 95% CI, 1.8-6.8; P<0.001), lymph node involvement (HR =3.5; 95% CI, 1.5-8.2; P=0.004), and age (HR =1.0; 95% CI, 1.0-1.1; P=0.035). There were no significant differences between patients who did and did not receive adjuvant therapy following resection (all P>0.05). A second multivariable model included only those patients who received adjuvant therapy (n=39). Lack of inclusion of a platinum agent in the adjuvant regimen (HR =2.4; 95% CI, 1.0-5.8; P=0.040) and larger tumor diameter (HR =1.3; 95% CI, 1.0-1.6; P=0.047) were independent predictors of inferior survival.

CONCLUSIONS

Addition of a platinum agent to adjuvant regimens for resected PASC may improve survival among these high-risk patients, though collaborative prospective investigation is needed.

Clinicopathological features and surgical outcomes of adenosquamous carcinoma of the pancreas: a retrospective analysis of patients with resectable stage tumors

PURPOSE

Adenosquamous carcinoma of the pancreas is a rare subtype of pancreatic cancer. We herein describe the clinicopathological features of surgically resected cases of adenosquamous carcinoma of the pancreas.

METHODS

From 2001 to 2011, 132 patients underwent R0 resection for Stage IIA or IIB pancreatic cancer. The survival rate, pathological features and recurrence status were reviewed.

RESULTS

Out of 132 patients, 121 patients had tubular adenocarcinoma, and only seven had adenosquamous carcinoma (ASC). The incidence of ASC increased with the tumor size. The overall survival and disease-free survival periods of the patients with ASC were significantly shorter than those of patients with tubular adenocarcinoma (p = 0.0153 and p = 0.0045). The histological findings revealed more marked venous invasion in ASC compared to tubular adenocarcinoma (G1, G2 and G3). The proportion of v3 cases, which denotes the most severe venous invasion, was 31.3 % in G1, 47.3 % in G2, 60.0 % in G3 and 71.4 % in ASC cases, respectively. Other factors, including lymphatic and nerve invasion, were not correlated with the histological subtypes. The incidence of ASC was 11.1 % in the tumors more than 6 cm in diameter, and 0 % in those less than 2 cm in diameter.

CONCLUSIONS

We revealed that adenosquamous carcinoma of the pancreas is associated with a poor outcome, and also clarified its clinicopathological features.

Clinical characteristics of adenosquamous carcinoma of the pancreas: a matched case-control study

OBJECTIVES

Adenosquamous carcinoma of the pancreas (ASC) is a variant of pancreatic ductal adenocarcinoma (PDAC), but the prognosis remains unclear. The purpose of this study was to clarify the prognosis of ASC using a matched case-control design.

METHODS

We evaluated clinical characteristics of ASC treated between 2001 and 2011 in our institution. As controls, PDAC cases matched with ASC cases for sex, age, pretreatment Eastern Cooperative Oncology Group performance status, location, initial therapy and American Joint Committee on Cancer TNM staging for pancreatic cancer were also evaluated.

RESULTS

Of the 914 cases of pancreatic neoplasm, 28 cases (3.06%) of ASC were identified, and 56 cases of PDAC were matched as controls. Median overall survival (OS) was significantly worse for ASC (8.38 months) than for PDAC (15.75 months; hazard ratio [HR], 1.94; 95% confidence interval, 1.07-3.51; P = 0.026). Of the 22 unresected cases, median OS was again significantly worse for ASC (4.67 months) than for PDAC (12.36 months; HR, 2.39; 95% confidence interval, 1.27-4.51; P = 0.007).

CONCLUSION

These results demonstrate that ASC is more aggressive than PDAC.

Adenosquamous carcinoma of the pancreas: multidetector-row computed tomographic manifestations and tumor characteristics

OBJECTIVE

The purpose of this article was to present the adenosquamous carcinoma (ASqC) of the pancreas: multidetector-row computed tomographic (CT) features and tumor characteristics.

MATERIALS AND METHODS

The clinical data and CT studies of 12 patients with pathologically proven ASqC of the pancreas between the dates February 2001 and February 2010 were retrospectively analyzed.

RESULTS

The presenting symptoms of ASqC of the pancreas were nonspecific. Elevated serum levels of carbohydrate antigen 19-9, carbohydrate antigen 12-5, and carcinoembryonic antigen were noted. The tumor was most commonly involved in the pancreatic head in 6 patients, with the dilation of the common bile duct and the upstream main pancreatic duct. All ASqCs exhibited invasive growth. No calcification and intratumoral hemorrhage were noted in ASqCs. Ten tumors showed enhancement in the early arterial phase and persistent enhancement in the portal vein phase.

CONCLUSION

The typical CT appearance of ASqC was solitary oval or round without any capsule and a defined margin. The dilation of the main pancreatic duct and/or the common bile duct was always discovered. The huge infiltrative lesion outside the pancreas was detected in the tail and/or the body of the pancreas. Not only the elevation of carbohydrate antigen 19-9 is common, but also Ca12-5 and CEA, whereas human alpha fetoprotein elevation is not observed. The enhancement pattern of tumor showed persistence in the portal vein phase.