You collect a sample from a mass on the liver of a dog using…

You collect a sample from a mass on the liver of a dog using ulstrasound guided biopsy techniques. You make a slide, stain it, and observe mesenchymal cells on cytology. The cells are all of the same type, size, shape, and appearance. The pathology report comes back from the lab stating that the cytology sample is benign. What does this mean?