Tumor growth depends on both proliferative and apoptotic rate of neoplastic cells. High proliferation index is a well-known negative prognostic factor in canine lymphomas, whereas little is known about apoptotic activity. We describe proliferative and apoptotic rates in different canine lymphoma subtypes at diagnosis. Flow cytometry (FC) was used to assess the percentage of proliferating cells (Ki67%) and of apoptotic cells (AnnV%) in 128 lymph node (LN) aspirates from dogs with lymphoma. Proliferation/apoptosis ratio (PAR) and turnover index (TI; Ki67% + AnnV%) were then calculated for each case.

High-grade B-cell lymphomas showed high values for both Ki67% and AnnV%, low-grade B-cell lymphomas showed low Ki67% and high AnnV%, high-grade T-cell lymphomas showed high Ki67% and low AnnV%, and low-grade T-cell lymphomas showed low levels of both parameters. Lymphoblastic lymphomas had the highest PAR values. High-grade B-cell lymphomas had the highest TI values while small clear cells lymphomas the lowest.

The panorama of proliferative and apoptotic activity widely varies among lymphoma subtypes. Our results lay the ground for future clinical and pharmacological studies.

肿瘤的生长取决于肿瘤细胞的增殖和凋亡率。高增殖指数是犬淋巴瘤中众所周知的阴性预后因素，而对细胞凋亡活性知之甚少。我们描述了不同的犬淋巴瘤亚型在诊断时的增殖和凋亡率。流式细胞术（FC）用于评估来自患有淋巴瘤的狗的128个淋巴结（LN）吸出液中增殖细胞（Ki67％）和凋亡细胞（AnnV％）的百分比。然后计算每种情况下的增殖/凋亡率（PAR）和周转指数（TI； Ki67％+ AnnV％）。

高级别B细胞淋巴瘤的Ki67％和AnnV％值均高，低级别B细胞淋巴瘤的Ki67％和AnnV％低，高级别T细胞淋巴瘤的Ki67％和AnnV％高，低度T细胞淋巴瘤的两个参数均较低。淋巴母细胞淋巴瘤的PAR值最高。高级别B细胞淋巴瘤的TI值最高，而小透明细胞淋巴瘤的TI值最低。

淋巴瘤亚型之间增殖和凋亡活性的范围差异很大。我们的结果为将来的临床和药理研究奠定了基础。