Sokołowska J, Micun J, Malicka E, Lechowski R
Department of Morphological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland.
Pol J Vet Sci. 2012;15(4):727-34. doi: 10.2478/v10181-012-0111-6.
Forty five lymphomas, 14 of T cell origin, 28 of B cell and 3 with null-cell phenotype, were included in this study. Tumors were classified according to the updated Kiel classification system adapted to canine lymphomas. The percentage of Ki67+ cells and mitotic index (MI) were estimated in each specimen. Most of lymphomas (39 of 45) had high proliferation activity. Among them in 27 cases 50-70% of lymphoma cells expressed Ki67, the highest Ki67 expression (> 70% Ki67+ cells) was identified less frequently, in 12 cases. Moderate Ki67 expression (20-50% positive cells) was observed in 5 cases, only one tumor had low Ki67 expression (< 20% positive cells). Lower percentage of Ki67+ cells was usually accompanied with lower MI. The mean MI values in discussed groups differed significantly. Mean MI value was also significantly higher in T cell than in B cell lymphomas (4.30 vs. 3.33). Moreover, high positive correlation between the expression of Ki67 and MI was found (r = 0.668; P < or = 0.001). In T-cell tumors the correlation was very high (r = 0.83; P < or = 0.001) and in B-cell lymphomas the correlation was high (r = 0.61; P < or = 0.001). There were also differences between mean MI values in the lymphomas of different morphological subtypes, but in some of them high variations in the range of MI values were identified and wide overlaps of MI between individual cases from different subtypes were observed. Because of differences in the proliferation activity in single cases of the same subtype of lymphoma, the proliferation activity assessment may be helpful to chose appropriate scheme of treatment and should be commonly performed during routine histopathological diagnosis of canine lymphomas.
本研究纳入了45例淋巴瘤，其中14例起源于T细胞，28例起源于B细胞，3例为无细胞表型。肿瘤根据适用于犬淋巴瘤的更新后的基尔分类系统进行分类。对每个标本估计Ki67+细胞的百分比和有丝分裂指数（MI）。大多数淋巴瘤（45例中的39例）具有高增殖活性。其中，27例淋巴瘤细胞中有50%-70%表达Ki67，Ki67表达最高（>70% Ki67+细胞）的情况较少见，为12例。5例观察到中等Ki67表达（20%-50%阳性细胞），只有1例肿瘤Ki67表达低（<20%阳性细胞）。Ki67+细胞百分比越低，通常MI也越低。所讨论组的平均MI值差异显著。T细胞淋巴瘤的平均MI值也显著高于B细胞淋巴瘤（4.30对3.33）。此外，发现Ki67表达与MI之间存在高度正相关（r = 0.668；P≤0.001）。在T细胞肿瘤中相关性非常高（r = 0.83；P≤0.001），在B细胞淋巴瘤中相关性较高（r = 0.61；P≤0.001）。不同形态学亚型淋巴瘤的平均MI值之间也存在差异，但其中一些亚型的MI值范围变化很大，不同亚型的个体病例之间MI有广泛重叠。由于同一亚型淋巴瘤单病例的增殖活性存在差异，增殖活性评估可能有助于选择合适的治疗方案，并且在犬淋巴瘤的常规组织病理学诊断中应常规进行。
