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Aleskandarany MA, Rakha EA, Macmillan RD, Powe DG, Ellis IO, Green AR (2011) MIB1/Ki-67 labelling index.
Poorly differentiated, marked nuclear pleomorphism, necrosis, corresponds to ENETs G3 by Ki67 labelling index.
For many tumours, the rate of cell proliferation as assessed by Ki-67 immunoreactivity correlates with tumour grade and clinical course. In Non-Hodgkin lymphoma a labelling index of less than 20% is seen in low grade lymphomas, greater than 20% is associated with high grade lymphomas. Low grade lymphomas with a labelling index in excess of 5% have a worse prognosis than those with an index of less than 5%.
Cell cycle state within tumors was determined by immunostaining for the recently described marker minichromosome maintenance protein 2 (MCM2), together with Ki67. Labelling indices for both markers were correlated with tumor grade, mitotic index, and time to first recurrence. The MCM2 labelling indices were significantly higher than the Ki-67 labelling indices. Both indices showed a significant correlation with the mitotic index and both showed significant increases with increasing grade of myxofibrosarcoma. The MCM2 labelling index.
Ki-67 and MIB-1 monoclonal antibodies are directed against different epitopes of the same proliferation-related antigen. Ki-67 and MIB1 may be used on fixed sections.  MIB-1 is used in clinical applications to determine the Ki-67 labelling index. One of its primary advantages over the original Ki-67 antibody (and the reason why it has essentially supplanted the original antibody for clinical use) is that it can be used on formalin-fixed paraffin-embedded sections, after heat-mediated antigen retrieval (see next section below).
Materials and Methods: 22 KCOTs were evaluated retrospectively. The actual proliferative activity of the KCOT was measured by Ki-67 labelling index and argyrophilic nucleolar organizing regions AgNOR count per nucleus. Results: Recurrence occurred in 3 patients (13. 6%) during the follow-up period (mean follow-up, 37. 8 months) The Ki-67 and AgNOR counts were significantly higher in the recurrent lesions comparing to the non-recurrent lesions.
Rodriguez-Pereira C, Suárez-Penaranda JM, Vázquez-Salvado M, Sobrido MJ, Abraldes M, Barros F, et al. Value of MIB-1 labelling index (LI) in gliomas and its correlation with other prognostic factors. J Neurosurg Sci 2000;44:203-10.