Clinical outcomes of patients with resectable pancreatic acinar cell carcinoma

Genomic Profiling Reveals Germline Predisposition and Homologous Recombination Deficiency in Pancreatic Acinar Cell Carcinoma

PURPOSE

To determine the genetic predisposition underlying pancreatic acinar cell carcinoma (PACC) and characterize its genomic features.

METHODS

Both somatic and germline analyses were performed using an Food and Drug Administration-authorized matched tumor/normal sequencing assay on a clinical cohort of 28,780 patients with cancer, 49 of whom were diagnosed with PACC. For a subset of PACCs, whole-genome sequencing (WGS; n = 12) and RNA sequencing (n = 6) were performed.

RESULTS

Eighteen of 49 (36.7%) PACCs harbored germline pathogenic variants in homologous recombination (HR) and DNA damage response (DDR) genes, including BRCA1 (n = 1), BRCA2 (n = 12), PALB2 (n = 2), ATM (n = 2), and CHEK2 (n = 1). Thirty-one PACCs displayed pure, and 18 PACCs harbored mixed acinar cell histology. Fifteen of 31 (48%) pure PACCs harbored a germline pathogenic variant affecting HR-/DDR-related genes. BRCA2 germline pathogenic variants (11 of 31, 35%) were significantly more frequent in pure PACCs than in pancreatic adenocarcinoma (86 of 2,739, 3.1%; P < .001), high-grade serous ovarian carcinoma (67 of 1,318, 5.1%; P < .001), prostate cancer (116 of 3,401, 3.4%; P < .001), and breast cancer (79 of 3,196, 2.5%; P < .001). Genomic features of HR deficiency (HRD) were detected in 7 of 12 PACCs undergoing WGS, including 100% (n = 6) of PACCs with germline HR-related pathogenic mutations and 1 of 6 PACCs lacking known pathogenic alterations in HR-related genes. Exploratory analyses revealed that in PACCs, the repertoire of somatic driver genetic alterations and the load of neoantigens with high binding affinity varied according to the presence of germline pathogenic alterations affecting HR-/DDR-related genes and/or HRD.

CONCLUSION

In a large pan-cancer cohort, PACC was identified as the cancer type with the highest prevalence of both BRCA2 germline pathogenic variants and genomic features of HRD, suggesting that PACC should be considered as part of the spectrum of BRCA-related malignancies.

A resected case of acinar cell carcinoma of the pancreas with liver metastasis following chemotherapy using modified FOLFIRINOX

BACKGROUND

Acinar cell carcinoma of the pancreas is a rare exocrine malignancy representing less than 1% of all pancreatic neoplasms. It has been reported that it responds to treatment differently from pancreatic ductal adenocarcinoma and the treatment algorithm for acinar cell carcinoma usually depends on the stage of the respective tumor and the patient's current status.

CASE PRESENTATION

A 60-year-old man presented with upper abdominal pain and anorexia. Abdominal ultrasonography showed a large-sized hepatic mass and he was referred to our hospital. Contrast-enhanced computed tomography demonstrated a 110-mm low-density area occupying the right hemi-liver and an enhanced mass of 70 × 56 mm in the tail of the pancreas, which seemed to directly infiltrate into the spleen. The case was diagnosed as acinar cell carcinoma with a simultaneous liver metastasis identified by liver biopsy. Upfront resection of pancreatic cancer with distant metastasis might not be considered as an optimal choice, and in this case chemotherapy was administered prior to curative resection. Chemotherapy using the modified FOLFIRINOX regimen was undertaken, resulting in a partial remission; the liver tumor reduced in size from 110 to 47 mm and the pancreatic tumor from 70 to 40 mm. The patient then safely underwent curative hepatic resection with distal pancreato-splenectomy. Histological examinations revealed small-sized atypical cells with large nuclei that had formed acinar patterns, and immunostaining with trypsin was positive in tumor cells, which was in accordance with acinar cell carcinoma. More than 3 years later, the patient is doing well without any recurrence.

CONCLUSION

Aggressive and curative surgery in combination with chemotherapy such as FOLFIRINOX could be a treatment option to achieve long-term survival in cases of acinar cell carcinoma with liver metastases.

Pancreatic acinar cell carcinoma: A comprehensive review

Acinar cell carcinoma (ACC) is a rare pancreatic malignancy with distinctive clinical, molecular, and morphological features. The long-term survival of ACC patients is substantially superior to that of pancreatic adenocarcinoma patients. As there are no significant patient series about ACCs, our understanding of this illness is mainly based on case reports and limited patient series. Surgical resection is the treatment of choice for patients with the disease restricted to one organ; however, with recent breakthroughs in precision medicine, medicines targeting the one-of-a-kind molecular profile of ACC are on the horizon. There are no standard treatment protocols available for people in which a total surgical resection to cure the condition is not possible. As a result of shared genetic alterations, ACCs are chemosensitive to agents with activity against pancreatic adenocarcinomas and colorectal carcinomas. The role of neoadjuvant or adjuvant chemoradiotherapy has not been established. This article aims to do a comprehensive literature study and present the most recent information on acinar cell cancer.

Painful lower limb nodules as first symptom of resectable pancreatic acinar cell cancer: a case report

BACKGROUND

Pancreatic panniculitis is characterized by subcutaneous fat necrosis and is a rare presentation of an underlying pancreatic disease, appearing in approximately 2-3% of all patients with a pancreatic disease. The nodules usually involve the lower extremities. Pancreatic panniculitis is commonly associated with acute or chronic pancreatitis, and occasionally with pancreatic cancer, especially acinar cell carcinoma.

CASE PRESENTATION

A 77-year-old Caucasian woman with no significant medical history was referred to our center with multiple painful, itchy, and warm red/blue cutaneous nodules on the left lower leg. These skin lesions were consistent with the clinical diagnosis of panniculitis. The skin biopsy obtained showed a predominantly lobular panniculitis with fat necrosis of which the aspect was highly suspicious for pancreatic panniculitis. Further analysis revealed high lipase serum of > 3000 U/L (normal range < 60 U/L), and on computed tomography scan a mass located between the stomach and the left pancreas was seen. Endoscopic ultrasonography-guided fine-needle biopsy confirmed the diagnosis of acinar cell carcinoma. After discussing the patient in the pancreatobiliary multidisciplinary team meeting, laparoscopic distal pancreatectomy including splenectomy and en bloc wedge resection of the stomach due to tumor in-growth was performed. The cutaneous nodules on both legs disappeared 1-2 days after surgery. No long-term complications were reported during follow-up. One year after surgery, the patient presented with similar symptoms as preoperatively. Computed tomography scan showed local recurrence and distal metastases, which were subsequently confirmed by biopsy. She started with palliative folinic acid-fluorouracil-irinotecan-oxaliplatin chemotherapy but stopped after two cycles because of disease progression. The patient died 2 months later, 13 months after surgical resection.

CONCLUSION

This case illustrates the importance of clinically recognizing cutaneous nodules and pathological recognizing the specific microscopic changes as sign of a (malignant) pancreatic disease.

Imaging and Clinicopathological Features of Acinar Cell Carcinoma

Background

Acinar cell carcinoma (ACC) is a rare pancreatic epithelial malignancy that poses a significant threat. However, there are few related clinical studies. The present study aimed to analyze the imaging and pathological features of ACC to provide a reference for better diagnosis and treatment planning.

Methods

Thirty-nine with ACC, referred to Qianfoshan Hospital, Qilu Hospital and Provincial Hospital in Shandong Province from December 2012 to December 2020, were enrolled. Their imaging and clinicopathological features were analyzed. They were followed up for 1 year, and Cox regression was used to analyze the factors affecting patient prognosis.

Results

ACC was more common in the middle-aged and elderly and peaked at approximately 60 years. The clinical manifestations of the patients were mostly flatulence and upper abdomen pain. The tumor was located in the head of the pancreas in 19 cases, with an average size of 5.8 cm. We found nerve invasion and liver metastasis in one case each. 8 patients showed irregular amorphous tumor calcification on plain computed tomography and 5 showed high and low signals on T1- and T2-weighted images, respectively. Immunohistochemistry revealed 100.0% positive rates for CK, β-catenin, and Ki-67. Thirty-three patients underwent surgical resection, and the 2-year overall mortality rate was 25.6%. Cox analysis revealed that smoking was an independent risk factor affecting patient prognosis.

Conclusion

An in-depth understanding of the imaging and clinicopathological features of ACC is conducive to better diagnosis and treatment planning for ACC and subsequent improvement in patient prognosis.

Curative remnant total pancreatectomy for recurrent pancreatic acinar cell carcinoma: A case report

Introduction and importance

Acinar cell carcinoma (ACC) of the pancreas is a rare pancreatic cancer subtype (incidence, 0.5–2%) with unclear epidemiology and prognosis. Sometimes, repeat resection including total pancreatectomy is required for recurrence. We report a case of ACC recurring in the remnant pancreatic head after distal pancreatectomy that was successfully cured by remnant pancreatic resection following combination therapy with nab-paclitaxel (nab-PTX) and gemcitabine (GEM).

Case presentation

A 64-year-old woman was referred for pancreatic tumour treatment. CT revealed a 46-mm tumour in the pancreatic body, and endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) indicated ACC. Distal pancreatectomy was performed, and the final diagnosis was ACC. CT 18 months later showed a 34-mm tumour in the remnant pancreatic head revealed as ACC by EUS-FNA. Portal vein invasion was apparent, so neoadjuvant chemotherapy with nab-PTX and GEM was administered, and remnant pancreatic resection (total pancreatectomy) was performed. No recurrence or distant metastasis was present more than 6 months later.

Clinical discussion

Mean survival time for ACC is 18–47 months, and prognosis is good compared with pancreatic ductal adenocarcinoma (PDAC). ACC tends to extend and grow along the main pancreatic duct, which increases the recurrence rate to 50–60%. EUS and EUS-FNA were useful for evaluating tumour extension and diagnosis. Repeat pancreatic resection that included total pancreatectomy was feasible and could be performed safely.

Conclusion

ACC has a better prognosis than PDAC but with a higher recurrence rate. Aggressive surgical resection that included remnant total pancreatotomy with chemotherapy was useful in treating ACC.

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Acinar cell carcinoma (ACC) of the pancreas is a rare type of pancreatic tumour.

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ACC has good prognosis compared with pancreatic ductal adenocarcinoma, but the recurrence rate is high.

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Surgical resection that includes remnant pancreatic resection is useful for pancreatic tumours.

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Neoadjuvant and adjuvant chemotherapy are useful in treating ACC.

Rapid Response to the Combination of Lenvatinib and Sintilimab in a Pancreatic Acinar Cell Carcinoma Patient With Elevated Alpha-Fetoprotein: A Case Report

A 48-year old woman was diagnosed with metastatic pancreatic acinar cell carcinoma (PACC) and with a marked elevation in alpha-fetoprotein (AFP), this being a recognized but uncommon feature of PACC. As she refused chemotherapy, the combined therapy of lenvatinib and sintilimab (lenvatinib 8 mg, orally, qd; and sintilimab 100 mg, intravenous glucose tolerance test, q21d) was given, which conferred significant tumor shrinkage and long progression-free survival (>21 months). This study is the first report and description of a PACC demonstrating favorable response to the combination therapy of an antiangiogenic agent and immunotherapy.

Clinical Characteristics of Resected Acinar Cell Carcinoma of the Pancreas: A Korean Multi-Institutional Study

Simple Summary

Pancreatic acinar cell carcinoma accounts for less than 1% of primary pancreatic neoplasms. Because of its rarity, its characteristics and clinical outcomes remain unclear. Treatment strategies for pancreatic acinar cell carcinoma have relied on those of pancreatic ductal adenocarcinoma. In previous studies, it has been difficult to identify its characteristics due to the lack of cohort numbers in single institutional studies with detailed data and the lack of detailed data in large cohort multi-institutional studies. This retrospective multicenter cohort used a database founded in 2015 by the Korean Association of Hepato-Biliary Pancreatic Surgery. This database has collected nationwide patient data with details. In the present study, we aimed to better understand clinical outcomes of resected pancreatic acinar cell carcinoma and to lay the groundwork for establishing proper treatment strategies.

Abstract

Given the rare incidence of pancreatic acinar cell carcinoma (PACC), its post-resection clinical outcomes remain unclear. Treatment strategies for PACC have relied on those of pancreatic ductal adenocarcinoma (PDAC). The present study retrospectively investigated clinicopathologic characteristics of resected PACC registered in the Korea Tumor Registry System Biliary Pancreas database. Among 59 patients with a mean age of 59.2 years and a male predominance (83.1%), 43, 5, 7, and 4 had pure PACC, ductal differentiations, mixed neuroendocrine carcinomas, and intraductal and papillary variants, respectively. The mean tumor size was 4.6 cm, consisting of eight at T1, 26 at T2, and 25 at T3 stages. Metastasis to regional lymph node was identified in 15 (25.4%) patients. Thirty-one (52.5%) patients received adjuvant therapy. Five-year survival rate was 57.4%. The median survival was 78.8 months. In survival comparison according to the stage with AJCC system, N stage (lymph node metastasis), but not T stage, showed significant differences (p = 0.027). Resected PACC appeared to have clinical outcomes distinct from those of PDAC in this nationwide study. Therefore, large-scale multinational studies are needed to overcome the rarity of PACC and to establish an appropriate treatment strategies and staging system.

Survival Outcomes of Acinar Cell Pancreatic Cancer: A National Cancer Database Analysis

OBJECTIVES

Acinar cell pancreatic carcinomas (ACPCs) are rare neoplasms accounting for 1% to 2% of pancreatic tumors in adults. The objective of this study is to evaluate the benefit of chemotherapy in the adjuvant setting in resected ACPC and in the palliative setting for metastatic ACPC.

METHODS

Data were obtained from all US hospitals that contributed to the National Cancer Database between 2004 and 2014. Cases were identified using the histology code 8550.

RESULTS

A total of 593 patients with ACPC were identified. The mean age was 64.4 years (range, 18-90 years), with a male preponderance (72.8%, n = 432). Localized stage disease comprised 52.3% (n = 310) of patients. Among localized ACPC patients, 88.0% (n = 191) underwent surgery and 50.6% (n = 91) received adjuvant chemotherapy. The 5-year overall survival in those who received adjuvant treatment was slightly higher than those who did not receive adjuvant treatment (46.7% vs 44.8%, P = 0.3271). Among advanced-stage ACPC patients, 67.6% received chemotherapy, which translated into improved 5-year overall survival compared with no chemotherapy (8.1% vs 0%, P < 0.0001).

CONCLUSIONS

Chemotherapy in the palliative setting for advanced-stage ACPC patients was associated with improved survival. Adjuvant therapy did not translate into significant survival benefit.

Presentation and outcome of mixed neuroendocrine non-neuroendocrine neoplasms of the pancreas

BACKGROUND/OBJECTIVES

Mixed neuroendocrine non-neuroendocrine neoplasms (MiNEN) of the pancreas and periampullary region are extremely rare and heterogeneous malignancies. Literature is sparse, clinical management is not standardized and little is known about survival outcomes. The aim of this study was to identify pathological and radiological features of MiNEN and assess the outcome of surgical management.

METHODS

Patients undergoing surgery for pancreatic and periampullary MiNEN between 2001 and 2019 were retrospectively analysed based on a prospective database. Histological, radiological and clinical features were assessed. Survival was analysed in a nested case-control study and matched-pair analyses with pure neuroendocrine neoplasms (pNEN) and ductal adeno- or acinar cell carcinomas of the pancreas. A literature review with focus on survival after surgical resection was additionally performed.

RESULTS

Of 13 patients with MiNEN, 5 had acinar-MiNEN and 8 adeno-MiNEN. Two of 5 (40%) acinar-MiNEN and one adeno-MiNEN patients had liver metastases. All but one adeno-MiNEN (88%) showed preoperative radiological features of pancreatic adenocarcinoma, 3 of 5 (60%) acinar-MiNEN exhibited mainly neuroendocrine features. No surgical mortality was observed. The 5-year overall survival rate in all MiNEN was 40%. Five-year survival rate was 58% in adeno-MiNEN and comparable to that of matched ductal adenocarcinomas (36%) and pNEN (48%). Five-year overall survival rate was 20% in acinar-MiNEN, compared to 39% in acinar carcinoma patients and 59% in matched pNEN patients.

CONCLUSIONS

MiNEN are rare and difficult to distinguish from pure adenocarcinoma or neuroendocrine neoplasm preoperatively. Surgical resection would therefore be the treatment of choice in localized tumors.

The contemporary trend in worsening prognosis of pancreatic acinar cell carcinoma: A population-based study

BACKGROUND

Primary acinar cell carcinoma (ACC) is a rare exocrine tumor of the pancreas with unclear clinical characteristics. Our goal was to determine the incidence and update the clinical characteristics and outcomes of ACC.

METHODS

Through the Surveillance, Epidemiology, and End Results (SEER) database, we identified 252 patients with the latest diagnosis of ACC (2004-2016). The age-adjusted incidence (AAI) was calculated using the SEER*Stat Software version 8.3.6. The Kaplan-Meier method was used to draw survival curves and differences among them were compared by the log-rank test. Cox proportional hazards models were used to evaluate factors that had independent predictive effects on the overall survival.

RESULTS

The AAI of pancreatic ACC was on the rise with the mean age at diagnosis of 63.79±14.79 years. Most patients (15.9%) had poorer differentiated tumors. The patients presented with distant stage were 54.4% compared with 53.1% between 1988 and 2003. The 1-, 2-, and 5-years survival rates for pancreatic ACC patients were 53.5%, 34.6%,17.5%, respectively (compared with 78.5%, 67.0%, and 42.8%, between 1988 and 2003). The multivariate COX analysis showed that the patient's age, surgery, chemotherapy, and summary stage, but not marital status were independent prognosis factors for ACC.

CONCLUSIONS

Pancreatic ACC is a highly malignant tumor with an increasing incidence in recent years. The rate of distant metastasis is increasing and the survival rate is worse than in the past, suggesting that it may require more aggressive treatment and follow-up. Surgery, radiotherapy, and chemotherapy are all effective treatments, but prospective studies are still needed to verify them.

Patients With Acinar Cell Carcinoma of the Pancreas After 2005: A Large Population Study

OBJECTIVES

Acinar cell carcinoma of the pancreas is a rare tumor with limited data. We aim to evaluate the characteristics, treatments, and outcomes of pancreatic acinar cell carcinoma after 2005.

METHODS

We retrospectively reviewed patients with pancreatic acinar cell carcinoma treated in Peking University Cancer Hospital and Institute (2005-2018) and identified cases from Surveillance, Epidemiology, and End Results database (2005-2015).

RESULTS

A total of 306 cases in our institute (n = 11) and Surveillance, Epidemiology, and End Results database (n = 295) were identified. The median age was 67 years, and 73.5% were male. The 5-year survival was 36.8% for all patients (median, 27 months). About 37% underwent surgical resection. The 5-year survival was 65.6% for resected patients as compared with 16.9% for unresected ones (P < 0.0001). Among locoregional and metastatic diseases, surgery significantly prolonged survival as well (P = 0.0003). Stage IV patients who received chemotherapy had a better survival than those without it (median, 16 vs 3 months; P = 0.0019). Aging, stage IV, and no surgery were independent predictors of poor overall survival.

CONCLUSIONS

For pancreatic acinar cell carcinoma, surgery is a potentially curative treatment contributing to long-term survival and suggested even in advanced diseases. Chemotherapy improved survival for metastatic patients.

Long-term survival of two patients with recurrent pancreatic acinar cell carcinoma treated with radiofrequency ablation: A case report

BACKGROUND

Pancreatic acinar cell carcinoma (PACC) is a rare type of malignant pancreatic cancer that represents approximately 1% of all pancreatic neoplasms. Due to its very low incidence, only a few retrospective studies are available. Although surgery is the first choice for treatment, most patients experience recurrence (mainly in the liver) and there are no clear recommendations for patients with advanced disease.

CASE SUMMARY

We report two patients with PACC treated with surgery who experienced tumour recurrence in the liver. Patient 1 carried a germline mutation in the APC gene. Both patients were treated with gemcitabine plus oxaliplatin and gemcitabine plus capecitabine as first- and second-line therapies, respectively. After a favourable response to chemotherapy, the patients underwent radiofrequency ablation of the remaining liver metastases. For patient 1, we documented a relapse in the liver after a disease-free period of 9 mo, and treatment with gemcitabine plus capecitabine was restarted. The patient achieved a complete response, and he remains alive without evidence of disease recurrence after six years. After radiofrequency ablation, patient 2 experienced disease-free survival for 21 mo, when peritoneal relapse was diagnosed and treated with chemotherapy. The patient achieved a stable disease state for nearly two years; nevertheless, further progressive disease was documented, and he died seven years after the first relapse.

CONCLUSION

PACC presents different biological behaviours than pancreatic adenocarcinoma. Multidisciplinary treatment involving local ablative therapies may be considered for PACC.

Nomogram to Predict Cancer-Specific Survival in Patients with Pancreatic Acinar Cell Carcinoma: A Competing Risk Analysis

Background: The objective of this study was to evaluate the probability of cancer-specific death of patients with acinar cell carcinoma (ACC) and build nomograms to predict overall survival (OS) and cancer-specific survival (CSS) of these patients. Methods: Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Patients diagnosed with ACC between 2004 and 2014 were retrospectively collected. Cancer-specific mortality and competing risk mortality were evaluated. Nomograms for estimating 1-, 2- and 3-year OS and CSS were established based on Cox regression model and Fine and Grey's model. The precision of the 1-, 2- and 3-year survival of the nomograms was evaluated and compared using the area under receiver operating characteristic (ROC) curve (AUC). Results: The study cohort included 227 patients with ACC. The established nomograms were well calibrated, and had good discriminative ability, with a concordance index (C-index) of 0.742 for OS prediction and 0.766 for CSS prediction. The nomograms displayed better discrimination power than 7th or 8th edition Tumor-Node-Metastasis (TNM) stage systems in training set and validation set for predicting both OS and CSS. The AUC values of the nomogram predicting 1-, 2-, and 3-year OS rates were 0.784, 0.797 and 0.805, respectively, which were higher than those of 7th or 8th edition TNM stage systems. Regard to the prediction of CSS rates, the AUC values of the nomogram were also higher than those of 7th or 8th edition TNM stage systems. Conclusion: We evaluated the 1-, 2- and 3-year OS and CSS in patients with ACC for the first time. Our nomograms showed relatively good performance and could be considered as convenient individualized predictive tools for prognosis.