A matched-cohort analysis of 192 pancreatic anaplastic carcinomas and 960 pancreatic adenocarcinomas: A 13-year North American experience using the National Cancer Data Base (NCDB)

Abstract

Background: Anaplastic pancreatic carcinoma (APC) is a rare and poorly characterized disease. We sought to compare the clinical characteristics and outcomes of APC to pancreatic adenocarcinoma (PDAC).

Methods: The American National Cancer Data Base was queried for patients with resected APC and PDAC using histologic and operative codes. APC cases were matched 1:5 with PDACs based on age, sex, pathologic tumor stage, operative margin status, lymph node positivity ratio, and use of adjuvant chemotherapy.

Results: After 1:5 matching, 192 APCs and 960 PDACs were analyzed. When comparing APC vs PDAC the median tumor size was 45 mm (interquartile range, 33-60) vs 30 mm (interquartile range, 23-40; P < .001), and metastatic nodal disease was present in 40.6% and 38.0% of the cases (P = .25), respectively. APC cases were distributed equally between the head and the body/tail region of the pancreas (50%), while PDAC cases were located mainly in the head of the pancreas (75%; P < .001). Although the resected APC group had a lesser survival during the first year after the diagnosis (51% vs 69%; P = .029), the overall survival was similar in the 2 groups, with 21.6% vs 17.4% alive at 5 years, respectively for APC and PDAC (P = .32). Subgroup analysis of patients with APC with (n = 18) versus those without (n = 80) osteoclastlike giant cells showed a greater 5-year survival (50% versus 15%, P < .001).

Conclusion: Patients with resected APC tend to present with large tumors equally distributed between the head and body/tail of the pancreas. While APC is thought to have a more aggressive biology, our matched analysis showed similar overall survival compared with PDAC. The presence of osteoclastlike giant cells portends a significantly better prognosis compared with other histologic features of APCs.