Deep Node Surgery in Dogs: Ilio‐Sacral Lymphadenectomy Carries Higher Risk, Study Finds

Complications of Medial Retropharyngeal, Axillary, and Ilio‐Sacral Lymphadenectomy in 127 Dogs With Malignant Tumors

Luca Ciammaichella, Jessica Campanerut, Luciano Pisoni, Veronica Cola, Stefano Zanardi, Armando Foglia, Chiara Ferrari, Dina Guerra, Laura Marconato, Sara Del Magno

Background

Lymphadenectomy has become more common in canine oncology as sentinel lymph node (LN) mapping allows removal of nodes that are not easily palpable, such as medial retropharyngeal, axillary, or ilio-sacral LNs. While superficial LN excisions are generally safe, deeper approaches may carry greater surgical risk. This study aimed to describe complication rates and identify risk factors for these three types of lymphadenectomy in dogs with malignant tumors.

Methods

Retrospective cohort study of 127 dogs undergoing 140 lymphadenectomies (86 axillary, 27 medial retropharyngeal, 27 ilio-sacral) between 2017 and 2023 at the University of Bologna. All cases had preoperative LN mapping (CT-lymphography or indirect lymphangiography) and ≥1 month follow-up. Data collected included tumor type, LN characteristics, anesthesia duration, intra- and postoperative complications, and histopathology. Complications were graded using VCOG-CTCAE v2. Univariate and multivariate analyses tested associations with risk factors.

Results

Intraoperative complications: 3/140 (2%) overall; hemorrhage in 2/27 (7%) ilio-sacral dissections, and difficulty locating an axillary LN in 1/86 (1%). Enlarged/metastatic LNs were more prone to intraoperative complications.

Postoperative complications: 32/140 (23%) overall. Rates were 41% for ilio-sacral, 26% for medial retropharyngeal, and 16% for axillary approaches. Most were mild (regional edema, seromas, wound issues). One grade 3 wound dehiscence after ilio-sacral lymphadenectomy required revision surgery.

Risk factors: On univariate analysis, ilio-sacral procedures, enlarged/metastatic LNs, and longer follow-up were associated with higher complication rates. However, no factor retained significance on multivariate analysis.

Histopathology: 30% of excised LNs were metastatic, highest in mast cell tumors (46%).

Outcomes: No deaths due to surgery; median follow-up 225 days. Most complications were minor and manageable.

Limitations

Single-center retrospective design; surgical techniques varied; relatively small numbers for retropharyngeal and ilio-sacral groups limited statistical power. Follow-up and complication grading were dependent on medical records.

Conclusions

Axillary and medial retropharyngeal lymphadenectomies in dogs are generally safe with low complication rates, mostly minor and self-limiting. Ilio-sacral lymphadenectomy carries a higher risk of hemorrhage and postoperative complications, especially when LNs are enlarged or metastatic. Careful case selection, meticulous surgical technique, and intraoperative mapping may help reduce risks.

Disclaimer: The summary generated in this email was created by an AI large language model. Therefore errors may occur. Reading the article is the best way to understand the scholarly work. The figure presented here remains the property of the publisher or author and subject to the applicable copyright agreement. It is reproduced here as an educational work. If you have any questions or concerns about the work presented here, reply to this email.