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

Long-term survival after systemic chemotherapy, chemoradiotherapy, and maintenance therapy for an older adult patient with recurrent pancreatic acinar cell carcinoma

Pancreatic acinar cell carcinoma (PACC) is a rare cancer with no specific treatment. The treatment and chemotherapy for PACC are selected according to pancreatic ductal adenocarcinoma (PDAC). Herein, we describe a recurrent PACC case of an older adult patient. The patient was treated with systemic chemotherapy, chemoradiotherapy, and maintenance therapy based on the pathologic germline BRCA2 variant, resulting in long-term survival. The pathogenic BRCA variant is detected more frequently in patients with PACC than in those with PDAC. The BRCA variant significantly impacts treatment selection and prognosis; therefore, early genomic analysis is recommended when treating PACC.

A narrative review on rare types of pancreatic cancer: should they be treated as pancreatic ductal adenocarcinomas?

Pancreatic cancer is one of the deadliest malignancies in humans and it is expected to play a bigger part in cancer burden in the years to come. Pancreatic ductal adenocarcinoma (PDAC) represents 85% of all primary pancreatic malignancies. Recently, much attention has been given to PDAC, with significant advances in the understanding of the mechanisms underpinning disease initiation and progression, along with noticeable improvements in overall survival in both localized and metastatic settings. However, given their rarity, rare histological subtypes of pancreatic cancer have been underappreciated and are frequently treated as PDAC, even though they might present non-overlapping molecular alterations and clinical behavior. While some of these rare histological subtypes are true variants of PDAC that should be treated likewise, others represent separate clinicopathological entities, warranting a different therapeutic approach. In this review, we highlight clinical, pathological, and molecular aspects of rare histological types of pancreatic cancer, along with the currently available data to guide treatment decisions.

Comprehensive review of pancreatic acinar cell carcinoma: epidemiology, diagnosis, molecular features and treatment

Pancreatic acinar cell carcinoma is a rare form (0.2-4.3%) of pancreatic neoplasm with unique clinical and molecular characteristics, which largely differ from pancreatic ductal adenocarcinoma. Pancreatic acinar cell carcinoma occurs more frequently in males and can occur in children. Serum lipase is elevated in 24-58% of patients with pancreatic acinar cell carcinoma. Pancreatic acinar cell carcinomas tend to be large at diagnosis (median tumour size: ~5 cm) and are frequently located in the pancreas head. Radiologically, pancreatic acinar cell carcinoma generally exhibits a solid appearance; however, necrosis, cystic changes and intratumoral haemorrhage can occur in larger lesions. Immunostaining is essential for the definitive diagnosis of pancreatic acinar cell carcinoma. Compared with pancreatic ductal adenocarcinoma, pancreatic acinar cell carcinoma has a more favourable prognosis. Although radical surgery is recommended for patients with pancreatic acinar cell carcinoma who do not have distant metastases, the recurrence rate is high. The effectiveness of adjuvant therapy for pancreatic acinar cell carcinoma is unclear. The response to FOLFIRINOX is generally favourable, and some patients achieve a complete response. Pancreatic acinar cell carcinoma has a different genomic profile compared with pancreatic ductal adenocarcinoma. Although genomic analyses have shown that pancreatic acinar cell carcinoma rarely has KRAS, TP53 and CDKN2A mutations, it has a higher prevalence of homologous recombination-related genes, including BRCA1/2 and ATM, than pancreatic ductal adenocarcinoma, suggesting high sensitivity to platinum-containing regimens and PARP inhibitors. Targeted therapies for genomic alternations are beneficial. Therefore, genetic testing is important for patients with pancreatic acinar cell carcinoma to choose the optimal therapeutic strategy.

Treatment characteristics and outcomes of pure Acinar cell carcinoma of the pancreas - A multicentric European study on radically resected patients

BACKGROUND

Acinar cell carcinomas (ACC) belong to the exocrine pancreatic malignancies. Due to their rarity, there is no consensus regarding treatment strategies for resectable ACC.

METHODS

This is a retrospective multicentric study of radically resected pure pancreatic ACC. Primary endpoints were overall survival (OS) and disease-free survival (DFS). Further endpoints were oncologic outcomes related to tumor stage and therapeutic protocols.

RESULTS

59 patients (44 men) with a median age of 64 years were included. The median tumor size was 45.0 mm. 61.0% were pT3 (n = 36), nodal positivity rate was 37.3% (n = 22), and synchronous distant metastases were present in 10.1% of the patients (n = 6). 5-Years OS was 60.9% and median DFS 30 months. 24 out of 31 recurred systemically (n = 18 only systemic, n = 6 local and systemic). Regarding TNM-staging, only the N2-stage negatively influenced OS and DFS (p = 0.004, p = 0.001). Adjuvant treatment protocols (performed in 62.7%) did neither improve OS (p = 0.542) nor DFS (p = 0.159). In 9 cases, radical resection was achieved following neoadjuvant therapy.

DISCUSSION

Radical surgery is currently the mainstay for resectable ACC, even for limited metastatic disease. Novel (neo)adjuvant treatment strategies are needed, since current systemic therapies do not result in a clear survival benefit in the perioperative setting.