Centre for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal.
Clinical Department, Lisbon, Portugal.
Vet Comp Oncol. 2024 Dec;22(4):641-650. doi: 10.1111/vco.13018. Epub 2024 Oct 10.
Melanoma is one of the most common canine oral malignant tumours and is highly aggressive and metastatic, even at the early stages of development. Surgery relies on wide excision of the primary tumour and regional lymphadenectomy, with or without adjuvant therapy. Tumour location and size are important when considering staging, which ultimately affects the curative intent of surgery. Nevertheless, absolute tumour volume (TV) is not related to the vast phenotypic variability within canine breeds. This study aimed to determine the cutoff values of two ratios-tumour-to-head volume (THR) and tumour-to-body volume (TBR)-and assess whether they could be associated with the odds of finding metastasis at presentation and/or the likelihood of achieving tumour-free excision margins. A retrospective case series involving 51 dogs was used to evaluate the preoperative head/neck and chest computed tomography and histopathology of the primary mass and excised lymph nodes. Higher TV, THR% and TBR% values were associated with bone lysis and mitotic count (MC). The Ki67 index was significantly associated with local and distant metastases at presentation, whereas MC was associated with local metastasis alone. Tumour-infiltrated surgical margins were associated with caudally located tumours, regardless of the tumour size. Dogs with lymph node metastasis at presentation were seven times more prone to have local relapse. TV, THR% and TBR% values were positively associated with local lymph node metastasis at presentation. Cutoff values for both TV and TBR% were proposed to predict lymph node metastasis at presentation (TV = 6.423 cm and TBR% = 0.043), being supported by post-surgical survival analysis.
黑色素瘤是最常见的犬口腔恶性肿瘤之一，具有高度侵袭性和转移性，即使在早期阶段也是如此。手术依赖于原发肿瘤的广泛切除和区域淋巴结清扫，辅以或不辅以辅助治疗。在考虑分期时，肿瘤位置和大小很重要，这最终会影响手术的治疗意图。然而，绝对肿瘤体积（TV）与犬种内广泛的表型变异性无关。本研究旨在确定两个比值（肿瘤与头体积比（THR）和肿瘤与体体积比（TBR））的截止值，并评估它们是否与术前发现转移的可能性和/或实现无肿瘤切缘的可能性相关。本研究回顾性地纳入了 51 只犬，评估了原发性肿块和切除的淋巴结的术前头颈部和胸部计算机断层扫描和组织病理学。较高的 TV、THR%和 TBR%值与骨溶解和有丝分裂计数（MC）相关。Ki67 指数与术前局部和远处转移显著相关，而 MC 仅与局部转移相关。肿瘤浸润性手术切缘与肿瘤尾部位置有关，而与肿瘤大小无关。术前有淋巴结转移的犬发生局部复发的风险增加 7 倍。TV、THR%和 TBR%值与术前局部淋巴结转移呈正相关。提出了 TV 和 TBR%的截止值来预测术前淋巴结转移（TV=6.423 cm 和 TBR%=0.043），并通过术后生存分析得到支持。
