Prognostic significant of osteoclast-like giant cells in undifferentiated carcinoma of pancreas

Abstract

Presenter: Ryosuke Misawa MD, PhD | SUNY Downstate Medical Center Brooklyn Background: Undifferentiated carcinoma of the pancreas (UDC) is defined as containing large eosinophilic pleomorphic cells and/or ovoid-to-spindle-shaped cells and has a poor prognosis. On the other hand, undifferentiated carcinoma with osteoclast-like giant cells of the pancreas (UCOG) comprises osteoclast-like giant cells (OGCs) is suggested to have a better prognosis. However, the number of cases are limited and only case reports and their reviews are available in English literature. The aim of this study was to evaluate the prognostic significance of OGCs using the national cancer database. Methods: A retrospective analysis investigated the US National Cancer Data Base and evaluated patients who were diagnosed with UDC or UCOG from 2004 to 2014. Prognosis, demographic, and clinical features were compared between the two groups. Results: The study identified 1681 patients, 255 were in the UCOG group and 1426 were in the UDC group. The two groups were well matched in demographic profile including age ( 67.3 year-old vs 66.3 year-old, p = 0.146 ), sex ( male 56.9 % vs 57.4 %, p = 0.834 ), race distribution, and co-morbidities ( Charlson/Deyo Score ). The location of the UCOG group tumor were more common in the body and tail of the pancreas compared to the UDG group ( 32.0% vs 24.9%, p = 0.045 ), and as a consequence, more distal pancreatectomies were performed in the UCOG group ( 13.7% vs 7.2%, p = 0.011 ). Institution of chemotherapy ( 32.6% vs 29.3%, p = 0.12 ) and radiotherapy ( 20.0% vs 20.4%, p = 0.678 ) were similar in both groups. The size of the tumor at the time of diagnosis was larger in the UDC group ( 18.7 cm vs 19.7, p = 0.018 ). Lymph node metastasis were far more evident in the UDC group ( 61.7% vs 28.2%, p < 0.01 ). Kaplan-Meier analysis demonstrated superior survival for the UCOG group when compared to the UDC group ( mean OS 16.15 months vs 31.95 months, p = < 0.01 ). Conclusion: The clear prognostic significance of OGC is evident in undifferentiated carcinoma of the pancreas. Continual accumulation of UDC and UCOG cases in a database would clarify the effectiveness of surgical and neoadjuvant/adjuvant treatments in the future.