Indirect lymphography for sentinel lymph node detection in dogs with mast cell tumors.

Objective: The objective of this report is to describe the technique and diagnostic utility of indirect lymphography (IL) using water-soluble contrast for sentinel lymph node (SLN) mapping in dogs with mast cell tumors. Animals: Fifty-three dogs with 59 mast cell tumors were included. Procedure: Medical records were retrieved for dogs with a cytological diagnosis of mast cell tumor which also had IL performed for lymph node mapping. Dogs were excluded when surgery had been performed before presentation. Images were reviewed by a Board-certified radiologist for uptake of contrast within the sentinel lymph node. Results: Lymphography studies from 34 tumors (57.6%) were diagnostic (clearly identifiable lymphatics and sentinel lymph node). Lymphography studies from 12 tumors (20.3%) were partially diagnostic (identifiable lymphatics, but sentinel lymph node not highlighted). Lymphography studies from 13 tumors (22%) were non-diagnostic. Indirect lymphography studies were interpreted as either diagnostic or partially diagnostic in 77.9% of tumors. Conclusion: The results indicate that IL is a simple, available technique to allow for identification of a sentinel lymph node in dogs with mast cell tumors. Clinical relevance: Indirect lymphography is a simple and widely accessible technique for SLN mapping in dogs with mast cell tumors, particularly for the general practice environment.

Lymphographie indirecte pour la détection des ganglions lymphatiques sentinelles chez les chiens atteints de tumeurs mastocytaires. Objectif: L'objectif de ce rapport est de décrire la technique et l'utilité diagnostique de la lymphographie indirecte (IL) utilisant un contraste soluble dans l'eau pour la cartographie des ganglions lymphatiques sentinelles (SLN) chez les chiens atteints de tumeurs mastocytaires. Animaux: Cinquante-trois chiens avec 59 tumeurs mastocytaires ont été inclus. Procédure: Les dossiers médicaux ont été récupérés pour des chiens avec un diagnostic cytologique de tumeur mastocytaire qui ont également subi une IL pour la cartographie des ganglions lymphatiques. Les chiens ont été exclus lorsque la chirurgie avait été pratiquée avant la présentation. Les images ont été examinées par un radiologue certifié (ACVR) pour la prise de contraste dans le ganglion lymphatique sentinelle. Résultats: Les études de lymphographie de 34 tumeurs (57,6 %) étaient diagnostiques (lymphatiques clairement identifiables et ganglion sentinelle). Les études de lymphographie de 12 tumeurs (20,3 %) étaient partiellement diagnostiques (lymphatiques identifiables, mais ganglion sentinelle non mis en évidence). Les études de lymphographie de 13 tumeurs (22 %) étaient non diagnostiques. Les études de lymphographie indirecte ont été interprétées comme diagnostiques ou partiellement diagnostiques dans 77,9 % des tumeurs. Conclusion: Les résultats indiquent que l'IL est une technique simple et disponible pour permettre l'identification d'un ganglion lymphatique sentinelle chez les chiens atteints de tumeurs mastocytaires. Pertinence clinique: La lymphographie indirecte est une technique simple et largement accessible pour la cartographie du SLN chez les chiens atteints de tumeurs mastocytaires, en particulier dans le milieu de la pratique générale.(Traduit par Dr Serge Messier).

Outcomes and prognostic variables associated with primary abdominal visceral soft tissue sarcomas in dogs: A Veterinary Society of Surgical Oncology retrospective study.

Primary abdominal visceral soft tissue sarcomas (STSs) are rare tumours in dogs with little information available on outcomes. The goal of this retrospective, multi-institutional study was to describe the common tumour types, location and prognostic factors associated with primary abdominal visceral STSs. Medical records were searched for dogs with primary abdominal visceral STSs at six institutions and were retrospectively reviewed. Tumours were graded using the previously described grading scheme for STSs of the skin and subcutis when information in the histopathology report contained adequate details. Forty-two dogs were included in the study. Five dogs had grade I tumours, 11 had grade II and 15 had grade III tumours. The most common tumour type was leiomyosarcoma (38.1%). The most common tumour locations were the spleen (47.6%) and small intestine (23.8%). The local recurrence rate was low (4.7%). Metastasis was present at the time of surgery in 23.8%, and the overall metastatic rate was 40.4%. Mitotic index of ≥9 was associated with significantly shorter survival time (MST 269 days) compared with a mitotic index of <9 (MST not reached). The MST for grade I STSs was not reached, was 589 days for grade II and 158 days for grade III. Dogs with grade III tumours were more likely to develop metastatic disease. Neither location of the primary tumour nor the histologic subtype was associated with survival time. Histologic grading of abdominal visceral STSs using the previously described scheme is prognostic and should be provided on histopathology reports.