Abstract
Purpose
The World Health Organization (WHO) classification (2004) defines pancreatic endocrine carcinoma as tumors with gross local invasion or metastasis, and the mere occurrence of angioinvasion or perineural invasion constitute insufficient criteria of malignancy. The significance of this classification remains to be assessed in Japan.
Methods
Nonfunctioning “malignant” endocrine tumors hitherto reported in Japan were analyzed, reclassified according to the WHO criteria, and thereafter survival analyses were conducted.
Results
Ninety-five “malignant” endocrine tumors were reclassified into 40 cases of “well-differentiated endocrine tumor, uncertain behavior (UB)” and 55 cases of “well-differentiated endocrine carcinoma (WEC)” according to the WHO classification. The estimated overall 5-year survival of all patients was 86.0%. A univariate analysis revealed that the following factors were significant for overall survival: WHO classification (UB vs WEC; P = 0.001), lymph node metastasis (P = 0.008), distant metastasis (P = 0.023), and curability (P = 0.018). Of these, only the WHO classification was recorded as significant by a multivariate analysis (Cox proportional hazards regression; hazard ratio 6.2, 95% confidence interval 1.3–30, P = 0.025).
Conclusion
These data confirm the validity of the malignancy criteria of the WHO classification, thus indicating its impact on the diagnosis and treatment of pancreatic endocrine tumors in Japan.
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References
Heitz PU, Komminoth P, Perren A, Klimstra DS, Dayal Y, Bordi C, et al. WHO histological classification of tumours of the endocrine pancreas. In: DeLellis RA, Lloyd RV, Heitz PU, Eng C, editors. World Health Organization classification of tumours. Pathology and genetics of tumours of endocrine organs. 1st ed. Lyon: IARC Press; 2004. p. 177–182.
Kent RB 3rd, van Heerden JA, Weiland LH. Nonfunctioning islet cell tumors. Ann Surg 1981;193:185–190.
Heitz PU, Kasper M, Polak JM, Klöppel G. Pancreatic endocrine tumor. Hum Pathol 1982;13:263–271.
Thompson GB, van Heerden JA, Grant CS, Carney JA, Ilstrup DM. Islet cell carcinomas of the pancreas: a twenty-year experience. Surgery 1988;104:1011–1017.
Akatsu T, Kameyama K, Nogami Y, Kawachi S, Kitajima M, Kitagawa Y. Neoplastic endocrine differentiation of pancreatic ductal adenocarcinoma in a metastatic lymph node: report of a case. Surg Today 2007;37(11):1009–1012.
Bettini R, Boninsegna L, Mantovani W, Capelli P, Bassi C, Pederzoli P, et al. Prognostic factors at diagnosis and value of WHO classification in a mono-institutional series of 180 nonfunctioning pancreatic endocrine tumours. Ann Oncol 2008;19(5):903–908.
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Tsuchiya, A., Koizumi, M. & Ohtani, H. World Health Organization Classification (2004)-based Re-evaluation of 95 nonfunctioning “malignant” pancreatic endocrine tumors reported in Japan. Surg Today 39, 500–509 (2009). https://doi.org/10.1007/s00595-008-3923-3
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DOI: https://doi.org/10.1007/s00595-008-3923-3