Ki-67 is a powerful tool for grading neuroendocrine tumors among Egyptian patients: a 10-year experience
- 386 Downloads
Neuroendocrine tumors (NETs) arise in most organs of the body and share many common pathologic features. However, a variety of organ-specific systems have been developed for nomenclature, grading and staging of NETs, causing much confusion. In collaboration with WHO, the European Neuroendocrine Tumor Society (ENETS) recommended the use of either mitotic rate or Ki-67 labeling index (LI) for grading and classification. We aim to explore the profile of NETs in Egyptian patients and apply the ENETS system.
Materials and methods
This retrospective study was carried out on all cases of NETs diagnosed at the Pathology Department, National Cancer Institute, Cairo University, during the period from January 2000 to December 2009. Data about age, sex, anatomic site of tumor, tumor size, tumor stage and presence of nodal metastasis were retrieved. Ki-67 immunostaining and grading according to ENETS were done.
There was a trend toward increased mean age and tumor size and grade according to Ki-67, with significant statistical difference (p < 0.001 and 0.036, respectively). Estimation of mitotic count and Ki-67 LI was strongly associated with NET histopathologic types, but this association was stronger regarding Ki-67 LI than mitotic count (p = 0.002 and 0.035, respectively). On the other hand, there was discordance between grading according to mitotic count and grading according to Ki-67 LI in relation to NET histopathologic subtypes. Concordance between mitotic rate and Ki-67 LI was reported in 18.89 % of cases, while discordance occurred in 81.11 % of cases and was more prevalent in G3.
Ki-67 is a reliable and reproducible marker for grading of NETs and more superior than mitotic rate.
KeywordsNeuroendocrine tumors Grading Ki-67
Conflict of interest
- Capella C, Solcia E, Sobin LH, Arnold R (2000) Endocrine tumors of small intestine. In: Hamilton SR, Aeltonen LA (eds) WHO classification of tumors. Pathology and genetics of tumors of the digestive system. IARC Press, Lyon, pp 77–82Google Scholar
- Edge SB, Byrd DR, Compton CC et al (2010) American Joint Committee on Cancer Staging Manual, 7th edn. Springer, New York, pp 241–249Google Scholar
- Gosset A, Masson P (1914) Tumeurs endocrine de l’appendices. Presse Medicale 5:237Google Scholar
- Miller K (2002) Immunohistochemical techniques. In: Bancroft JD, Gamble M (eds) Theory and practice of histological techniques, 5th edn. Churchill, Livingstone, pp 421–464Google Scholar
- Pearse AGE (1969) The cytochemistry and ultrastructure of polypeptide-hormone producing cells of the APUD-series and the embryologic, physiologic and pathologic implication of the concept. J Histochem Cytochem 22:237–240Google Scholar
- Rindi G, Kloppel G, Couvelard A et al (2007) TNM staging of midgut and hindgut (neuro) endocrine tumors: a consensus proposal including a grading system. Virchows Arch 45(14):756–762Google Scholar
- Rindi G, Arnold R, Bosman FT, et al. (2010) Nomenclature and classification of neuroendocrine neoplasms of the digestive system. In: Bosman TF, Carneiro F, Hruban RH, Theise ND (eds) WHO Classification of tumors of the digestive system, 4th ed. International Agency for Research on Cancer (IARC), Lyon, 39(6): 707–712Google Scholar
- Solcia E, Kloppel G, Sobin LH (in collaboration with 9 pathologists from 4 countries) (2000) Histological typing of endocrine tumors. In: International histological classification of tumors, 2 ndedn, WHO. Berlin: SpringerGoogle Scholar
- Travis WD (2004) The concept of pulmonary neuroendocrine tumors. In: Travis WD, Brambilla E, Muller-Hermelink HK, Harris CC (eds) WHO classification of tumors. Pathology and genetics of tumors of lung, pleura, thymus and heart. IARC Press, Lyon, pp 19–20Google Scholar