Prediction of vascular invasion using a 7-point scale computed tomography grading system in adrenal tumors in dogs.

BACKGROUND: Previous studies evaluating the accuracy of computed tomography (CT) in detecting caudal vena cava (CVC) invasion by adrenal tumors (AT) used a binary system and did not evaluate for other vessels. OBJECTIVE: Test a 7-point scale CT grading system for accuracy in predicting vascular invasion and for repeatability among radiologists. Build a decision tree based on CT criteria to predict tumor type. METHODS: Retrospective observational cross-sectional case study. Abdominal CT studies were analyzed by 3 radiologists using a 7-point CT grading scale for vascular invasion and by 1 radiologist for CT features of AT. ANIMALS: Dogs with AT that underwent adrenalectomy and had pre- and postcontrast CT. RESULTS: Ninety-one dogs; 45 adrenocortical carcinomas (50%), 36 pheochromocytomas (40%), 9 adrenocortical adenomas (10%) and 1 unknown tumor. Carcinoma and pheochromocytoma differed in pre- and postcontrast attenuation, contralateral adrenal size, tumor thrombus short- and long-axis, and tumor and thrombus mineralization. A decision tree was built based on these differences. Adenoma and malignant tumors differed in contour irregularity. Probability of vascular invasion was dependent on CT grading scale, and a large equivocal zone existed between 3 and 6 scores, lowering CT accuracy to detect vascular invasion. Radiologists' agreement for detecting abnormalities (evaluated by chance-corrected weighted kappa statistics) was excellent for CVC and good to moderate for other vessels. The quality of postcontrast CT study had a negative impact on radiologists' performance and agreement. CONCLUSIONS AND CLINICAL IMPORTANCE: Features of CT may help radiologists predict AT type and provide probabilistic information on vascular invasion.

Evaluation of the neoplastic infiltration of the skin overlying canine subcutaneous soft tissue sarcomas: An explorative study.

Studies regarding the neoplastic infiltration of the skin overlying canine subcutaneous soft tissue sarcoma (sSTS) are lacking. In case of the absence of tumor infiltration, there would be the possibility of leaving this unaffected skin in place, thus simplifying surgery. The aim of the study was to investigate whether the skin overlying sSTSs is infiltrated by neoplastic cells. Dogs with sSTSs treated surgically were prospectively enrolled. After excision, the skin was dissected from the tumor along the natural surgical plane of cleavage and histologically evaluated. Twenty-nine dogs with an sSTS were included (22 grade I, 6 grade II, and 1 grade III). The sSTS-overlying skin was not tumor-infiltrated in 14/29 cases (48.3%). A higher frequency of infiltration was observed in higher grade sSTSs (grades II and III, 100%; P = .006); nevertheless, 8/22 grade I sSTSs (36%) also showed cutaneous infiltration. This infiltration involved the dermis of the skin directly in contact with the tumor (multifocal in 11 and diffuse in four cases). Although the cutaneous tumor infiltration is less frequent in grade I sSTSs and a wide excision may still be the safest treatment for any sSTS for a greater possibility of local control, this study opens the possibility to a less aggressive cutaneous excision, but still with a local curative intent, as only the skin directly in contact with the sSTS has been proven to be tumor-infiltrated. Additional studies are warranted to confirm that excision of only this skin may guarantee a complete local control, especially in lower-grade sSTSs.

Effects of rotation and osteotomy angulation on patellar tendon insertion position during circular tibial tuberosity osteotomy.

OBJECTIVE: To evaluate the influence of rotation of the tibial tuberosity (TT) in the sagittal plane and angulation of osteotomy in the frontal plane (FPA) on the displacement of patellar tendon (PT) insertion. STUDY DESIGN: Ex vivo biomechanical study. SAMPLE POPULATION: Canine tibiae (n = 36). METHODS: Nine groups of 4 tibiae each had a circular osteotomy of the TT at an FPA from -20° to +20° with increments of 5° for each group. The osteotomized TT was rotated by angles of rotation (AORs) of 10°, 20°, or 30° in the sagittal plane. The craniocaudal (CCD), distoproximal (DPD), and mediolateral (MLD) displacements of a marker located at the PT insertion on the TT were evaluated radiographically. Differences between groups were analyzed by Mann-Whitney U test and Friedman 2-way ANOVA. RESULTS: There was a significant correlation between the AOR and CCD. A positive FPA resulted in a high CCD and lateral shift of the TT at every AOR. Performing an osteotomy at an FPA of 0° produced the maximum amount of DPD. CONCLUSIONS: FPA and AOR during circular osteotomy of the TT influence the final displacement of the PT insertion in all 3 planes.