Buirkle Corinne L, Hlusko Katelyn C, Cole Robert C, Bergman Noelle, Tillson D Michael, Almond Gregory, Matz Brad M
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Auburn University, 1220 Wire Road, Auburn, Alabama 36849-5540, USA.
Can J Vet Res. 2025 Jan;89(1):3-10.
Sentinel lymph node (SLN) mapping has been shown to be important for staging in dogs with mast cell tumors (MCTs). Despite this, many patients are referred to an oncologist after surgical intervention has been carried out. It is unknown whether lymphatic drainage patterns are altered by surgery and whether postoperative SLN mapping can be reliably conducted. The objective of this study was to compare lymphatic drainage patterns from MCT sites before and after surgical removal to determine whether the SLN changes following tumor excision. Twenty-nine client-owned dogs with 31 cytologically diagnosed MCTs were prospectively enrolled, with 14 dogs (N = 15 MCTs) completing the study. Preoperative SLN mapping was conducted using radiographic indirect lymphography (IL). Water-soluble iodinated contrast (WIC) medium was injected peritumorally using a 4-quadrant technique and digital radiography was then used to assess lymphatic drainage patterns. Orthogonal projections were obtained every 1 to 2 min until the SLN was visualized, up to 20 min post-injection. Dogs were re-evaluated 2 to 5 wk postoperatively and radiographic IL was carried out again using the same protocol as previously described with WIC injected around the surgical scar line in a 4-quadrant technique. An SLN was identified for 15 MCTs in 14 dogs preoperatively and in 13/15 MCTs postoperatively. Sixteen dogs with 16 MCTs did not have postoperative lymphography and did not complete the study. Agreement between preoperative and postoperative SLNs was a complete match in 7/15 MCTs, a partial match in 5/15 MCTs, and no match in 3/15 MCTs. A negative IL study was obtained in 2/15 MCTs postoperatively. Complete agreement between preoperative and postoperative SLN identification was detected in 46.7% of cases and there was no agreement in 20% of cases. Surgical intervention did not change the time to SLN identification when carrying out radiographic IL. Thus, surgical removal of MCTs affects lymphatic drainage and can alter the SLN(s) detected. Clinicians should be aware of this finding and interpret results of postoperative lymph node staging with caution.
前哨淋巴结（SLN）定位已被证明对肥大细胞瘤（MCT）犬的分期很重要。尽管如此，许多患者在进行手术干预后才被转诊至肿瘤学家处。目前尚不清楚手术是否会改变淋巴引流模式，以及术后SLN定位能否可靠进行。本研究的目的是比较手术切除前后MCT部位的淋巴引流模式，以确定肿瘤切除后SLN是否发生变化。前瞻性纳入了29只客户拥有的患有31个经细胞学诊断的MCT的犬，其中14只犬（N = 15个MCT）完成了研究。术前使用放射间接淋巴造影（IL）进行SLN定位。采用四象限技术在肿瘤周围注射水溶性碘化造影剂（WIC），然后使用数字放射摄影评估淋巴引流模式。注射后每1至2分钟获取正交投影，直至SLN显影，最长至注射后20分钟。术后2至5周对犬进行重新评估，并使用与之前相同的方案再次进行放射IL，采用四象限技术在手术瘢痕线周围注射WIC。术前在14只犬的15个MCT中识别出SLN，术后在13/15个MCT中识别出SLN。16只患有16个MCT的犬未进行术后淋巴造影，未完成研究。术前和术后SLN完全匹配的有7/15个MCT，部分匹配的有5/15个MCT，不匹配的有3/15个MCT。术后2/15个MCT获得阴性IL研究结果。术前和术后SLN识别完全一致的病例占46.7%，20%的病例不一致。进行放射IL时，手术干预并未改变SLN识别时间。因此，手术切除MCT会影响淋巴引流，并可能改变检测到的SLN。临床医生应了解这一发现，并谨慎解释术后淋巴结分期结果。
