Survivin, ß-catenin, and ki-67 immunohistochemical expression in canine perivascular wall tumors: Preliminary assessment of prognostic significance.

High survivin expression has been correlated with poor outcomes in several canine tumors but not in soft tissue tumors (STTs). Survivin is a target gene of the Wnt/ß-catenin pathway, which is involved in human STT oncogenesis. Immunohistochemistry for survivin, ß-catenin, and Ki-67 was performed on 41 canine perivascular wall tumors (cPWTs), and statistical associations of protein expression and histopathologic and clinical variables with clinical outcomes were investigated. Immunohistochemically, there was nuclear positivity (0.9%-12.2% of tumor cells) for survivin in 41/41 (100%), cytoplasmic positivity (0 to > 75% of tumor cells) for survivin in 31/41 (76%), nuclear positivity (2.9%-67.2% of tumor cells) for ß-catenin in 24/41 (59%), and cytoplasmic positivity (0% to > 75% of tumor cells) for ß-catenin in 23/41 (56%) of cPWTs. All tumors expressed nuclear Ki-67 (2.2%-23.5%). In univariate analysis and multivariate analysis (UA and MA, respectively), every 1% increase of nuclear survivin was associated with an increase of the instantaneous death risk by a factor of 1.15 [hazard ratio (HR) = 1.15; P = .007]. Higher nuclear survivin was associated with grade II/III neoplasms (P = .043). Expression of cytoplasmic survivin, nuclear and cytoplasmic ß-catenin, and nuclear Ki-67 were not significantly associated with prognosis in UA nor MA. Tumor size was a significant prognostic factor for local recurrence in UA [subdistribution HR (SDHR) = 1.19; P = .02] and for reduced overall survival time in MA. According to UA and MA, a unitary increase of mitotic count was associated with an increase of the instantaneous death risk by a factor of 1.05 (HR = 1.05; P = .014). Nuclear survivin, mitotic count, and tumor size seem to be potential prognostic factors for cPWTs. In addition, survivin and ß-catenin may represent promising therapeutic targets for cPWTs.

Tumor-associated macrophages and tumor-infiltrating lymphocytes in canine cutaneous and subcutaneous mast cell tumors.

Cutaneous and subcutaneous mast cell tumors (MCTs) are common canine neoplasms characterized by variable biological behavior. Tumor-associated macrophages (TAMs) and tumor-infiltrating lymphocytes (TILs) can be effective prognostic markers in numerous human neoplasms and are increasingly investigated in dogs. The aim of this study was to characterize immune cells in canine MCTs and their relationship with histological location (cutaneous, subcutaneous) and histologic nodal metastatic status (HN0-3). Thirty-eight MCTs (26 cutaneous, 12 subcutaneous) from 33 dogs with known sentinel lymph node (SLN) metastatic status were immunolabeled for Iba1 (macrophages), CD20 (B cells), CD3 (T cells), and Foxp3 (regulatory T cells). Semiquantitative scoring of interstitial and perivascular CD3+, CD20+, and Foxp3+ cells and morphological evaluation of Iba1+ cells were performed. For each marker, the percent immunopositive area was evaluated by image analysis. All MCTs were diffusely infiltrated by Iba1+ cells and variably infiltrated by CD20+, CD3+, and rare Foxp3+ cells. Stellate/spindle Iba1+ cells were associated with HN2 and HN3 SLNs. Perivascular Foxp3+ cells, CD3+ cells, and percent CD3+ areas were increased in subcutaneous MCTs. Interstitial CD3+ cells were increased in cutaneous MCTs with HN0 SLNs. No differences in CD20+ cells were identified between cutaneous and subcutaneous MCTs and among SLN classes. MCTs were markedly infiltrated by TAMs and variably infiltrated by TILs. Stellate/spindle morphology of TAMs associated with HN2 and HN3 SLNs is suggestive of a pro-tumoral (M2) phenotype. Cutaneous and subcutaneous MCTs have different tumor-immune microenvironments, and T-cell infiltration might contribute to prevention of nodal metastatic spread of cutaneous MCTs.

Weishaar's classification system for nodal metastasis in sentinel lymph nodes: Clinical outcome in 94 dogs with mast cell tumor.

BACKGROUND: The therapeutic role and prognostic relevance of lymphadenectomy in mast cell tumor (MCT) has historically been evaluated on regional rather than sentinel lymph nodes. HYPOTHESIS/OBJECTIVES: To update information about the association of histological nodal (HN) classes with clinical outcome in dogs with MCT after tumor excision and extirpation of normal-sized sentinel nodes (SLN) guided by radiopharmaceutical. ANIMALS: Ninety-four dogs with histologically-confirmed treatment-naïve MCT (71 cutaneous, 22 subcutaneous and 1 conjunctival MCT) were included if without: distant metastases, lymphadenomegaly, concurrent mixed cutaneous, and subcutaneous MCT. METHODS: This was a monoistitutional cohort study. Tumors characteristics were retrieved and SLNs were classified according to Weishaar's system. Incidence of MCT-related events (local, nodal, distant relapse), de novo MCT or other tumors and death (MCT-related and non-MCT-related), were recorded. Incidence curves were compared among the HN classes. RESULTS: Twenty-seven dogs had HN0, 19 HN1, 37 HN2, and 11 HN3 SLN. Thirteen (2 HN0, 4 HN2, and 7 HN3) received adjuvant chemotherapies. Kiupel high grade, increasing number of SLN and lymphocentrums were associated with higher HN classes. Five dogs died for MCT-related causes: 1 low-grade (HN0) and 1 subcutaneous (HN3) had a local relapse, 2 high-grade had distant relapse (HN3-HN0) and 1 dog developed disease progression from a de novo subcutaneous MCT. No nodal relapse was registered. Fourteen dogs developed de novo MCTs. CONCLUSION/DISCUSSION: Low grade/low-risk MCT with nonpalpable and normal sized SLN have a favorable outcome independently from the HN. Result should be considered strictly related to the successful SLN detection guided pre- and intraoperative by radiopharmaceutical markers.

Impact of Surgical Lights on the Performance of Fluorescence-Guided Surgery Systems: A Pilot Study.

Fluorescence-guided surgery can aid in the intraoperative visualization of target tissues, with promising applications in human and veterinary surgical oncology. The aim of this study was to evaluate the performances of two fluoresce camera systems, IC-FlowTM and VisionsenseTM VS3 Iridum, for the detection of two non-targeted (ICG and IRDye-800) and two targeted fluorophores (AngiostampTM and FAP-Cyan) under different room light conditions, including ambient light, new generation LED, and halogen artificial light sources, which are commonly used in operating theaters. Six dilutions of the fluorophores were imaged in phantom kits using the two camera systems. The limit of detection (LOD) and mean signal-to-background ratio (mSBR) were determined. The highest values of mSBR and a lower LOD were obtained in dark conditions for both systems. Under room lights, the capabilities decreased, but the mSBR remained greater than 3 (=clearly detectable signal). LOD and mSBR worsened under surgical lights for both camera systems, with a greater impact from halogen bulbs on VisionsenseTM VS3 Iridium and of the LED lights on IC-Flow due to a contribution of these lights in the near-infrared spectrum. When considering implementing FGS into the clinical routine, surgeons should cautiously evaluate the spectral contribution of the lights in the operating theater.

Performance of two clinical fluorescence imaging systems with different targeted and non-targeted near-infrared fluorophores: a cadaveric explorative study.

Introduction: Near-infrared (NIR) fluorescence-guided surgery is increasingly utilized in humans and pets. As clinical imaging systems are optimized for Indocyanine green (ICG) detection, the usage of targeted dyes necessitates the validation of these systems for each dye. We investigated the impact of skin pigmentation and tissue overlay on the sensitivity of two NIR cameras (IC-FlowTM, VisionsenseTM VS3 Iridum) for the detection of non-targeted (ICG, IRDye800) and targeted (AngiostampTM, FAP-Cyan) NIR fluorophores in an ex vivo big animal model. Methods: We quantitatively measured the limit of detection (LOD) and signal-to-background ratio (SBR) and implemented a semi-quantitative visual score to account for subjective interpretation of images by the surgeon. Results: VisionsenseTM VS3 Iridum outperformed IC-FlowTM in terms of LOD and SBR for the detection of all dyes except FAP-Cyan. Median SBR was negatively affected by skin pigmentation and tissue overlay with both camera systems. Level of agreement between quantitative and semi-quantitative visual score and interobserver agreement were better with VisionsenseTM VS3 Iridum. Conclusion: The overlay of different tissue types and skin pigmentation may negatively affect the ability of the two tested camera systems to identify nanomolar concentrations of targeted-fluorescent dyes and should be considered when planning surgical applications.

Lymph node metastasis in feline cutaneous low-grade mast cell tumours.

OBJECTIVES: This retrospective study aimed to determine the incidence of nodal metastatic disease in cats affected by low-grade cutaneous mast cell tumours (MCTs) in our study population. METHODS: The clinical records of two centres were retrospectively searched for cats with cutaneous MCTs that had undergone lymphadenectomy of enlarged and non-enlarged lymph nodes. All primary tumours were histologically reviewed by two experienced pathologists and graded as high- or low-grade based on the grading system for feline cutaneous MCT. We graded the lymph nodes based on the grading scheme used for canine MCTs and considered HN2 and HN3 nodes to be metastatic. The number of patients with nodal metastasis was calculated. RESULTS: We identified 17 cats with cutaneous MCT resection and concurrent lymphadenectomy. All 21 MCTs were graded as low grade and 30 nodes were removed, with 12 being considered early or overtly metastatic (HN2 or HN3, respectively). Based on nodal status, 10/17 (59%) cats were affected by nodal metastasis in our population. CONCLUSIONS AND RELEVANCE: In contrast to previous reports, high percentage of cats with cutaneous MCTs in which lymphadenectomy was performed were presented with metastatic lymph nodes. The clinical relevance of this finding and a potential benefit of lymphadenectomy must be determined in future studies.

Salivary miR-21 is a potential biomarker for canine mast cell tumors.

MicroRNAs (miRNAs) are a class of noncoding RNA molecules playing a crucial role in tumor modulation targeting mRNA. This study aimed to validate the diagnostic potential of a panel of 3 miRNAs previously identified in canine mast cell tumors (MCTs), miR-21, miR-379, and miR-885, as markers of lymph node involvement in terms of histological absence (nonmetastatic: HN0; premetastatic: HN1) and presence (early-metastatic: HN2; overt-metastatic: HN3) of metastasis, in the saliva of mast cell tumor (MCT)-affected dogs by quantitative polymerase chain reaction (PCR). Forty-seven saliva samples were analyzed: 36 from MCT-affected dogs (12 subcutaneous [3 HN0-1 and 9 HN2-3] and 24 cutaneous [9 HN0-1 and 15 HN2-3-MCT]) and 11 from healthy dogs. MCT-group effects were investigated using analysis of variance (ANOVA). The origin of the tumor affected the expression of salivary miR-21 (P = .011) with an increase in cases with subcutaneous MCTs compared with the healthy group (P = .0005) and those with cutaneous MCTs (P = .004). Salivary miR-21 was higher in the HN2-3 class compared with the healthy group (P = .004). Salivary miR-885 was not affected by the presence of MCT, while miR-379 was not detected in saliva. The diagnostic potential of salivary miR-21 in discriminating MCT-affected dogs from the healthy group (AUC = 0.8917), cutaneous from subcutaneous (AUC = 0.8111), and subcutaneous HN0-1 (AUC = 0.7250) and HN2-3 (AUC = 0.9750) classes from healthy samples was demonstrated by receiver operating characteristic curve analysis. Overall, salivary miR-21 was identified as a promising tool, representing a novel approach to detecting MCT-associated epigenetic alterations in a minimally invasive manner.

Comparison of immediate and short-term outcomes of cricoarytenoid and thyroarytenoid lateralization in dogs with idiopathic laryngeal paralysis.

OBJECTIVE: To compare the immediate and short-term outcomes of thyroarytenoid lateralization (TAL) and cricoarytenoid lateralization (CAL) for the treatment of canine laryngeal paralysis in dogs. STUDY DESIGN: A prospective, clinical trial. ANIMALS: Fourteen client-owned dogs referred to our hospital because of bilateral laryngeal paralysis. METHODS: Dogs with confirmed laryngeal paralysis were randomly assigned to the CAL or TAL group. Video images of the rima glottidis obtained preoperatively, immediately postoperatively (t0), and 15 days postoperatively (t1) were digitized. The rima glottidis area was measured using image-analysis software. An increase in the rima glottidis area was expressed as a percentage of the preoperative area. RESULTS: The rima glottidis area increased by a mean of 152% at t0 and 127% at t1 for the TAL group and 205% at t0 and 199% at t1 for the CAL group compared with preoperative values. The increase in the rima glottidis area differed (P < .05) between the 2 groups at all postoperative time points. A reduction of the area occurred at t1 in both groups. There was no difference between t0 and t1 (P > .05) in the CAL group but there was a large difference (P < .05) in the TAL group. CONCLUSION: Cricoarytenoid lateralization and TAL were both effective for surgical abduction of the arytenoid cartilage. Although a reduction (P < .05) in the rima glottidis area occurred in the TAL group at t1, we observed no associated clinical signs. CLINICAL SIGNIFICANCE: Cricoarytenoid lateralization and TAL result in good short-term outcomes in dogs with laryngeal paralysis.

To map or not to map the cN0 neck: Impact of sentinel lymph node biopsy in canine head and neck tumours.

Tumour stage is a prognostic indicator for canine malignant head and neck tumours (MHNT). However, consensus is lacking on nodal staging in the absence of clinically apparent nodal disease (cN0 neck). This prospective observational study aims to determine the diagnostic accuracy of radiopharmaceutical and blue dye for sentinel lymph node biopsy (SLNB), to assess the correspondence between sentinel lymph node (SLN) and clinically expected regional lymph node (RLN) and the impact on staging of the procedure in dogs with MHNT and cN0 neck. Twenty-three dogs with MHNT and cN0 neck underwent tumour excision and SLNB guided by preoperative lymphoscintigraphy and intraoperative gamma-probe and blue dye. Diagnostic performances and detection rate were calculated. Correspondence between SLN and RLN, number of nodes excised, histopathological status of the SLN and complications related to the procedure were recorded. The mapping technique identified at least one SLN in 19/23 dogs, with a detection rate of 83%. The SLN did not correspond to the RLN in 52% of dogs. Multiple nodes were removed in 61% of dogs. At histopathology, eight (42%) dogs had SLN+, of which four differed from the RLN. Only minor self-limiting complications occurred in five (22%) dogs. Radiopharmaceutical and blue dye guidance is accurate (sensitivity 88.9%; specificity 100%) for SLNB in dogs with MHNT and cN0 and allowed the extirpation of unpredictable and/or multiple SLN with minimal morbidity. Incorporation of SLNB in the management of MHNT is desirable to correctly stage the cN0 neck, owing the unpredictability of the lymphatic drainage.

Renal venotomy for thrombectomy and kidney preservation in dogs with adrenal tumors and renal vein invasion.

OBJECTIVE: To describe the surgical technique and report the outcomes of adrenalectomy and thrombus removal with kidney preservation by renal venotomy in a population of dogs with adrenal tumors and vascular invasion into the renal vein (RV) and caudal vena cava (CVC). STUDY DESIGN: Short case series. ANIMALS: Five client-owned dogs that underwent adrenalectomy. METHODS: Dogs with adrenal tumors and vascular invasion into the RV and CVC were retrospectively enrolled in this multi-institutional study. Renal venotomy was performed at the time of adrenalectomy for tumor thrombus removal. Recorded data included signalment, clinical signs and results of laboratory testing, physical examination findings, diagnostic imaging results, surgical technique, surgical time, surgical complications, and outcome. RESULTS: Tumor thrombus was removed by renal venotomy in five dogs. In one dog with an ectopic adrenal tumor located ventral to the left kidney, the thrombus was occluding 90% of caval flow, and a small caval venotomy was required to remove it. Kidney preservation was achieved in all dogs. No significant intraoperative or postoperative complications occurred, and all dogs were discharged 3 to 4 days postoperatively. Median surgical time was 125 minutes (range, 80-210). At the end of the study, four dogs were alive without signs of recurrence, while one dog died of a suspected pulmonary embolism at 510 days. Median follow-up was 510 days (range, 279-890). CONCLUSION: Renal venotomy is feasible for thrombectomy in dogs with adrenal tumors and RV invasion and allowed for the preservation of the kidney in this case series, thus limiting perioperative morbidity.

Prognostic impact of clinical, haematological, and histopathological variables in 102 canine cutaneous perivascular wall tumours.

Identification of prognostic factors for perivascular wall tumours (PWTs) is desirable to accurately predict prognosis and guide treatment. 100 and two dogs with surgically excised PWTs without distant metastasis were retrospectively enrolled in this multi-institutional study, and the impact of pre-treatment leukocyte parameters, clinical and histopathological variables on local recurrence (LR) and overall-survival time (OST) were evaluated. Increasing values of white blood cell count (WBCC), neutrophil count (NC) and neutrophil-to-lymphocyte ratio (NLR) were significantly correlated with the hazard of LR in univariate analysis. WBCC and NC remained prognostic when adjusted for margins, grade, tumour size, location and skin ulceration, but lost their significance when adjusted for mitotic index and necrosis, whilst NLR remained prognostic only when close margins where categorised as infiltrated. Castrated males had a higher hazard of LR than intact males in univariate analysis, but significance was lost in multivariate models. Ulcerated PWTs and those located on the distal extremities had a higher hazard of LR both in univariate and multivariate analysis. Histological grade, necrosis, mitotic count, and infiltrated margins were all associated with LR both in univariate and multivariate analysis. Boxer breed, older age, ulceration, grade III, necrosis >50% and higher mitotic count were correlated with shorter OST, although breed and age lost their significance in multivariate analysis. Prognostication of surgically excised PWTs should be based on both clinical and histopathological variables. If validated in further studies, leukocyte counts and NLR may aid the clinician in identifying dogs at higher risk of LR before treatment.

Lip-to-nose flap for reconstruction of the nasal planum after curative intent excision of squamous cell carcinoma in cats: Description of technique and outcome in seven cases.

OBJECTIVE: To describe the surgical technique for nasal planum reconstruction with a lip-to-nose flap after curative intent surgical excision of squamous cell carcinoma (SCC) in cats and to report the surgical outcomes. STUDY DESIGN: Short case series. ANIMALS: Seven cats with SCC of the lateral (n = 6) or dorsal (n = 1) aspect of the nasal planum. METHODS: After tumor excision, a mucocutaneous lip-to-nose flap was harvested from the upper lip and transposed to reconstruct the nasal planum. Variables recorded included surgical time, surgical complications, healing complications, flap success rate, and cosmetic and long-term functional outcomes. RESULTS: Median surgical time was 67.5 minutes (range 49-80), and no intraoperative complications occurred. Postoperatively, six cats developed self-limiting edema of the muzzle, and one cat had nasal discharge for 2 days. No major complications occurred during the healing process, and all cats went on to achieve successful healing of their flap. A small area of partial-thickness necrosis developed at the cranial edge of the flap in three cats and healed spontaneously in all cases within a few days. According to owner satisfaction and periodic clinical assessment, cosmetic and long-term functional of outcomes were considered good in all cats. CONCLUSION: The lip-to-nose flap allowed for aesthetic and functional reconstruction of the nasal planum after curative intent surgical excision of feline SCC. CLINICAL SIGNIFICANCE: The lip-to-nose flap is an option for a single-stage reconstruction of the nasal planum following partial nasal planectomy in cats.

Lip-to-nose flap for nasal plane reconstruction in dogs: A cadaveric and in vivo feasibility study.

OBJECTIVE: To describe a local interpolation flap based on the upper lip for the reconstruction of the dorsal aspect of the nasal plane in dogs. STUDY DESIGN: Ex vivo and in vivo case report. ANIMALS: A 2-year-old medium-sized spayed female mixed-breed dog and a canine cadaver of a medium-sized mixed-breed dog. METHODS: A dorsal defect of the nasal plane of uncertain origin in a dog was reconstructed with a unilateral interpolation flap obtained from the caudal upper lip skin and mucosa (lip-to-nose flap). The procedure was first performed in a cadaveric model to assess its feasibility. RESULTS: The lip-to-nose flap allowed the reconstruction of a dorsal nasal plane defect with a satisfactory cosmetic outcome. The incorporation of the labial mucosa guaranteed a complete and uncomplicated wound healing of the flap; a small area of necrosis occurred at the donor site, which resolved in a few days. CONCLUSION: The use of a lip-to-nose flap was feasible in these 2 medium-sized dogs and led to satisfactory cosmetic outcome. CLINICAL SIGNIFICANCE: A lip-to-nose flap may be considered to reconstruct dorsal nasal plane defects in dogs and allows for a cosmetic outcome.