Pancreatic acinar cell carcinomas and mixed acinar-neuroendocrine carcinomas are more clinically aggressive than grade 1 pancreatic neuroendocrine tumours

Joo Young Kim, Jacqueline A. Brosnan-Cashman, Jiyoon Kim, Soyeon An, Kyoung Bun Lee, Haeryoung Kim, Do Youn Park, Kee Taek Jang, Young Ha Oh, Ralph H. Hruban, Christopher M. Heaphy, Seung Mo Hong

Research output: Contribution to journalArticlepeer-review

Abstract

Acinar cell carcinomas (ACCs) and mixed acinar-neuroendocrine carcinomas (MAcNECs) of the pancreas are extremely rare carcinomas with a significant component with acinar differentiation. To date, the clinicopathological behaviours of these neoplasms remain unclear. In this study, we evaluated the histopathological and molecular characteristics of 20 ACCs and 13 MAcNECs and compared them to a cohort of 269 well-differentiated pancreatic neuroendocrine tumours (PanNETs). Compared to PanNETs, both ACCs and MAcNECs had an advanced pT classification (p<0.001), as well as more prevalent lymphovascular and perineural invasion (p=0.002) and lymph node and distant metastases (p<0.001). Patients with MAcNECs had worse overall (p<0.001) and recurrence-free survival (p<0.001) than those with PanNETs, but no significant difference with those with ACCs. Subgroup analyses revealed that patients with ACCs and MAcNECs had significantly worse recurrence-free survival than those with grade 1 PanNET (p<0.001), and patients with MAcNECs also had worse overall survival than those with grade 1 and 2 PanNETs (p<0.001, and p=0.001). ACCs presented more commonly with intraductal growth (p=0.014) than MAcNECs, while MAcNECs more often had lymph node metastasis (p=0.012) than ACCs. The telomere maintenance mechanism Alternative Lengthening of Telomeres (ALT) was assessed by telomere-specific FISH, and ALT was detected in 1 of 20 ACCs and in three of the 13 MAcNECs. Patients with MAcNECs and ACCs had worse survival and more aggressive behaviour than those with grade 1 PanNETs; thus, the clinicopathological behaviour of MAcNECs resembles ACCs rather than PanNETs. Combined neuroendocrine and acinar cell immunohistochemical markers are helpful for differentiating these different tumour types.

Original languageEnglish (US)
Pages (from-to)336-347
Number of pages12
JournalPathology
Volume52
Issue number3
DOIs
StatePublished - Apr 2020

Keywords

  • Pancreas
  • acinar
  • carcinoma
  • neuroendocrine
  • tumour

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Fingerprint Dive into the research topics of 'Pancreatic acinar cell carcinomas and mixed acinar-neuroendocrine carcinomas are more clinically aggressive than grade 1 pancreatic neuroendocrine tumours'. Together they form a unique fingerprint.

Cite this