We recently conducted a second canine prostate study using targeted ultrasound contrast on a poodle, yielding similar results to the previous study of the German Shepherd.
Pre-contrast, the liver and gallbladder appeared normal. The spleen contained a 3.0 cm x 1.9 cm hypoechoic nodule dorsally. Both kidneys had a thickened and hyperechoic cortex with decreased corticomedullary definition and trivial renal pelvic dilation. The adrenal glands were normal and the urinary bladder contained an irregular mucosal mass craniodorsally. The prostate was enlarged, measuring 4.0 cm in diameter. The stomach, bowel, and region of the pancreas were normal.
Post-contrast, the filling within the spleen and the splenic nodule were different. Additionally, there was contrast accumulation within the medial half of the splenic nodule while the lateral half of the nodule remained hyperechoic. The ventral half of the prostate was contrast enhancing. A triangular region dorsally was non-contrast enhancing. And the sublumbar nodules were non-contrast enhancing.
Five separate biopsies of the prostate (two of the left lobe ventral, one of the right lobe ventral, and two of the dorsal) were performed. FNA of the splenic nodule was briefly attempted but aborted.
Conclusions from Images:
1. Prostatic mineralization with sublumbar lymphadenopathy. Heterogeneous enhancement. This finding suggests abnormal (potentially cancerous) tissue.
2. Heterogeneously-enhancing splenic nodule was seen with an interesting pattern – that similar to a sliver of a moon. We could see the contrast flowing through most of the area but sticking to a smaller area, indicating that this portion may contain cellular atypia.
Biopsy Results:
The biopsy results confirmed cellular atypia in the contrast enhancing regions of both the spleen and the ventral half of prostate.
Implications:
As diagnosticians, we’re constantly faced with whether an area is infectious, cancerous, or pre-cancerous. Both studies so far have revealed that contrast-enhancing ultrasound can be a reliable method for distinguishing inflammation from cancer.
The implications of both studies may be far-reaching, allowing for early detection of prostate cancer in both dogs and people using noninvasive ultrasound coupled with targeted ultrasound contrast. Historically, medical testing and imaging were initially performed on healthy small animals such as rats and mice during clinical trials, with findings later applied to humans. However, a new clinical research philosophy is beginning to emerge where cutting-edge diagnostics and medical care are being offered to both humans and pets afflicted with similar conditions. This comparative testing model may offer a better understanding of cancer in both humans and animals.
