Clinicopathological features of adenosquamous pancreatic cancer

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.

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.

Pathological transition as the arising mechanism for drug resistance in lung cancer

Despite the tremendous efforts for improving therapeutics of lung cancer patients, its prognosis remains disappointing. This can be largely attributed to the lack of comprehensive understanding of drug resistance leading to insufficient development of effective therapeutics in clinic. Based on the current progresses of lung cancer research, we classify drug resistance mechanisms into three different levels: molecular, cellular and pathological level. All these three levels have significantly contributed to the acquisition and evolution of drug resistance in clinic. Our understanding on drug resistance mechanisms has begun to change the way of clinical practice and improve patient prognosis. In this review, we focus on discussing the pathological changes linking to drug resistance as this has been largely overlooked in the past decades.

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.

R0 resection of pancreatic head carcinoma: Definition of surgical margins and influencing factors

Early diagnosis of pancreatic head carcinoma is difficult. Once diagnosed, it often has been in the advanced stage, the prognosis is poor, and five-year survival does not exceed 6%. R0 resection is the only way to obtain long-term survival in patients with pancreatic head cancer. Numerous clinical studies have shown that lack of retroperitoneal tissue dissection is the important reason for being unable to achieve R0 resection in pancreatic cancer patients. The proposed mesopancreas and total mesopancreas excision (TMpE) concept provides a better definition of retroperitoneal dissection, thereby increasing the rate of R0 resection effectively.

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.

The UPF1 RNA surveillance gene is commonly mutated in pancreatic adenosquamous carcinoma

Pancreatic adenosquamous carcinoma (ASC) is an enigmatic and aggressive tumor that has a worse prognosis and higher metastatic potential than its adenocarcinoma counterpart. Here we report that ASC tumors frequently harbor somatically acquired mutations in the UPF1 gene, which encodes the core component of the nonsense-mediated RNA decay (NMD) pathway. These tumor-specific mutations alter UPF1 RNA splicing and perturb NMD, leading to upregulated levels of NMD substrate mRNAs. UPF1 mutations are, to our knowledge, the first known unique molecular signatures of pancreatic ASC.

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

BACKGROUND

Adenosquamous carcinoma of the pancreas is rare. Our understanding of the disease and its prognosis comes mainly from small retrospective studies.

METHODS

Using the Surveillance, Epidemiology, and End Results (SEER) database (1988 to 2007), we identified patients with adenosquamous carcinoma (n = 415) or adenocarcinoma (n = 45,693) of the pancreas. The demographics, tumor characteristics, resection status, and survival were compared between the groups.

RESULTS

Compared with patients with adenocarcinoma, patients with adenosquamous carcinoma were more likely to have disease located in the pancreatic body and tail (44.6% versus 53.5%, P < 0.0001). While the stage distribution was similar between the two groups, adenosquamous carcinomas were more likely to be poorly differentiated (71% versus 45%, P < 0.0001), node positive (53% versus 47%, P < 0.0001), and larger (5.7 versus 4.3 cm, P < 0.0001). For locoregional disease, resection increased over time from 26% in 1988 to 56% in 2007. The overall 2-y survival was 11% in both groups. Following resection, patients with adenosquamous carcinoma had worse 2-y survival (29% versus 36%, P < 0.0001). Resection was the strongest independent predictor of survival for patients with locoregional pancreatic adenosquamous carcinoma (HR 2.35, 95% CI = 1.47-3.76).

CONCLUSIONS

This is the first population-based study to evaluate outcomes in adenosquamous carcinoma of the pancreas. Compared with pancreatic adenocarcinoma, adenosquamous carcinoma was more likely to occur in the pancreatic tail, be poorly differentiated, larger, and node positive. The long-term survival following surgical resection is significantly worse for adenosquamous cancers; however, patients with adenosquamous carcinoma can still benefit from surgical resection, which is the strongest predictor of survival.