Clinico-Pathologic and Prognostic Study of 59 Acinar Cell Carcinomas of the Pancreas
Stefano La Rosa, Volkan N Adsay, Luca Albarello, Sofia Asioli, Selenia Casnedi, Francesca Franzi, Alessandro Marando, Kenji Notohara, Fausto Sessa, Alessandro Vanoli, Lizhi Zhang, Carlo Capella. Ospedale di Circolo, Varese, Italy; Emory University, Atlanta, GA; San Raffaele Scientific Institute, Milan, Italy; University of Turin, Turin, Italy; Hospital De Hautepierre, Strasbourg, France; University of Insubria, Varese, Italy; Kurashiki Central Hospital, Kurashiki, Japan; University of Pavia, Pavia, Italy; Mayo Clinic, Rochester, MN
Background: Due to its relative rarity, many clinicopathologic characteristics of acinar cell carcinoma (ACC) remain to be further elucidated and there are not established prognostic factors.
Design: 59 ACCs were investigated for the following parameters: site, size, local infiltration, node and distant metastases, architectural pattern (acinar, pseudoglandular, trabecular, solid structure), nuclear atypia, presence of necrosis, expanding versus infiltrating growth, lymphovascular and perineural invasion, mitotic and Ki67 indices, BCL10, trypsin, CEL, amylase, lipase, PDX1, chromogranin A, CK19, CK7, and β-catenin expression.
Results: The patients were predominantly males (M/F:2.3). Mean age was 59 years (28-88 years). Mean tumor size was 7.8 cm (2-29 cm). 32 tumors showed an acinar/pseudoglandular pattern, while 27 a solid architecture often associated with an acinar/trabecular structure. BCL10 and trypsin were the most reliable immunohistochemical markers, while amylase and lipase were not. 45 patients underwent surgery, while 14 showed unresectable cancers. Surgery was statistically correlated with a better prognosis (p:0.0007). 10 cases showing more than 25% chromogranin A positive cells were classified as mixed endocrine/ACCs, but there was not a different survival between pure ACCs and mixed cancers. 12 patients were alive free of disease after a mean follow-up time of 78 months, 4 were alive with disease after a mean follow-up time of 43 months, while 34 died of disease after a mean follow-up time of 24 months. In operated patients, the factors significantly correlated with poor prognosis were UICC-stage (p:0.003) and, in particular, size >6.5cm (p:0.04), lymph node (p:0.03) and distant (p:0.008) metastases. Vascular and perineural invasion and CK19 expression also showed a trend for poor prognosis, but did not reach statistical significance.
Conclusions: ACCs show heterogeneous morphological features. Factors associated with adverse prognosis are stage including resectability, size, lymph node and distant metastases.
Wednesday, March 21, 2012 9:30 AM
Poster Session V # 247, Wednesday Morning