Department of Small Animal Clinical Science, Federal University of Santa Maria, Santa Maria, RS, Brazil.
Department of Pathology, Federal University of Santa Maria, Santa Maria, RS, Brazil.
Vet Clin Pathol. 2020 Sep;49(3):451-458. doi: 10.1111/vcp.12894. Epub 2020 Sep 23.
Mammary neoplasms are common tumors in intact female dogs. Fine-needle aspiration cytology (FNAC) is a valuable diagnostic tool and has gained some credibility in the diagnosis of mammary tumors in dogs. Prompt classification of canine mammary tumors using cytology would enhance feasibility as a prognostic tool and guide clinical and surgical management.
We aimed to examine background elements to differentiate mammary tumors using FNAC. We proposed to distinguish simple from complex and mixed tumors by identifying myoepithelial (ME) cells and different types of extracellular matrix. Additionally, we determined the accuracy of FNAC to differentiate benign from malignant tumors.
One hundred and one mammary tumors from female dogs were included in this study. We compared FNAC using histopathology as the gold standard. Cellular and background components were evaluated and identified. The cytologic accuracy, sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) for diagnosing malignancy were determined, excluding inadequate samples.
The cytologic-histologic agreement was 92.5% for simple carcinomas, 57.9% for complex-type carcinomas, 57.1% for mixed-type carcinomas, 27.3% for carcinosarcomas, and 100% for osteosarcomas. Myoepithelial cells were successfully identified using FNAC. Myxoid and chondroid/osteoid matrix were satisfactorily recognized. Cytologic accuracy, Se, Sp, PPV, and NPV for diagnosing malignancy were 99%, 100%, 83%, 99%, and 100%, respectively.
Chondroid/osteoid matrix was noted in mixed tumors but not in complex tumors. Myxoid matrix, often associated with ME cells, was noted in complex and mixed tumors. Mesenchymal cells were differentiated from ME cells, allowing the distinction of simple carcinomas with scirrhous reaction from complex and mixed tumors.
乳腺肿瘤是未绝育雌性犬常见的肿瘤。细针抽吸细胞学（FNAC）是一种有价值的诊断工具，在犬乳腺肿瘤的诊断中已获得一定的可信度。通过细胞学及时对犬乳腺肿瘤进行分类，将提高其作为预后工具的可行性，并指导临床和手术管理。
我们旨在利用 FNAC 检查鉴别乳腺肿瘤的背景元素。我们提出通过识别肌上皮（ME）细胞和不同类型的细胞外基质来区分单纯和复杂混合性肿瘤。此外，我们还确定了 FNAC 鉴别良性和恶性肿瘤的准确性。
本研究纳入了 101 例来自雌性犬的乳腺肿瘤。我们将 FNAC 与组织病理学进行比较，以组织病理学为金标准。评估并识别细胞和背景成分。排除不充分的样本后，确定用于诊断恶性肿瘤的细胞学准确性、敏感度（Se）、特异度（Sp）、阳性预测值（PPV）和阴性预测值（NPV）。
单纯癌的细胞学-组织学符合率为 92.5%，复杂型癌为 57.9%，混合性癌为 57.1%，癌肉瘤为 27.3%，骨肉瘤为 100%。FNAC 成功识别出 ME 细胞。成功识别出黏液样基质和软骨样/骨样基质。诊断恶性肿瘤的细胞学准确性、Se、Sp、PPV 和 NPV 分别为 99%、100%、83%、99%和 100%。
软骨样/骨样基质见于混合性肿瘤，但不存在于复杂型肿瘤中。黏液样基质常与 ME 细胞相关，见于复杂和混合性肿瘤中。间充质细胞与 ME 细胞不同，可区分伴有硬化反应的单纯癌与复杂和混合性肿瘤。
