Linfadenectomia dos ilíacos mediais em cadelas com neoplasmas mamários

Abstract

The objective of this study was to verify the effectiveness of the lymphatic marking technique for the medial iliac lymph node in bitches with mammary neoplasm, using the methylene blue pigment in different application sites (intrauterine and intradermal) and determine if there is lymphatic tissue affected, allowing to establish if the lymphaadectomy of the medial iliacs is important in patients with mammary neoplasm. Thirty-eight bitches were included in the study. The weigh 10.7±4.2 kg and 9.9±2.5 years old, with mammary neoplasms in different sites, ulcerated or not. Bitches were separated into two groups (GI and GU). In GU (17 animals), lymphatic marking was performed with intrauterine dye followed by medial iliac lymphadenectomy on the same side of the neoplasm, ovariohysterectomy and unilateral mastectomy. In GI (21 animals), ovariohysterectomy was performed followed by lymphatic marking with dye administered intradermally (around M5) and subsequent medial iliac lymphadenectomy and subsequent unilateral mastectomy. All animals received 1% methylene blue as dye. In GU, in 14 animals the iliac lymph nodes were stained by methylene blue, but in three animals, they were not stained and were excised in the same way after their location. In GI was possible to vizualize in all animals the mediated iliac lymph nodes in blue until one minute afterthe application. Laterhistopathological analysis of mammary neoplasms, 84.21% were classified as malignant (32 animals). There were no metastases in the animals with benign neoplasm. In 32 bitches with malignant neoplasm, metastasis of mammary neoplasm in the medial iliac lymph node was verified in three GI animals and in two of the GU, totalizing involvement of the referred lymph nodes in 15.62% of these patients. In two animals with medial iliac lymph node metastasis, it was not increased in volume. All lymph nodes that presented mammary neoplasm metastasis were stained with methylene blue. This study presents important innovations associated to the surgical management of mammary neoplasms in bitches, demonstrating the effectiveness of the lymph node marking with 1% methylene blue, especially when administered intradermally, as well as emphasizing the importance of the medial pelvic lymphadenectomy in bitches with this condition. In view of the results obtained, it is indicated that the lymphadenectomy of the medial iliac lymph nodes of mammary chain involved with the neoplasia is part of the treatment of canines with mammary neoplasms, if they will be submitted to celiotomy for ovariohysterectomy or by another indication, regardless of size, location and presentation of these lymph nodes.