Clinical, laboratory, histopathological adn image findings of prostatic adenocarcinoma in dog

Abstract

Prostate neoplasms are the main reproductive disorders affecting neutered dogs, being the adenocarcinoma the most common and developing signs of urinary and/or gastrointestinal tract. This tumor develops spontaneously in dogs, being malignant, very invasive and unresponsive to castration. Due the recent increase in reports and a high interference in the animals' quality of life, the objective of this study was to report a case of prostatic adenocarcinoma in an eight-year-old SRD dog with metastasis in bladder, peritoneum and mesentery. The animal presented dehydration, fever, difficulty for walking, severe pain, abdominal enlargement, apathy, hyporexia, hypodipsia and tenesmus. Rectal examination, identified a firm mass and incongruous in prostatic membrane. Two months before an orchiectomy was performed due a prostatomegaly. At the time, an ultrasound identified irregular prostate with cavity formations, spleen with hypoechogenic formation and bladder with hyperechogenic formation attached to the wall. Radiography was requested and fecaloma was observed. Thus, enterotomy and prostatectomy were required. In surgery, nodulations were identified in mesentery, peritoneum and spleen, in addition to a hemorrhagic focus and a palpable mass in the bladder. The prostate was attached to bone tissue, making the removal impossible. The animal was euthanized and prostatic histopathology identified acinar adenocarcinoma. Histological samples of peritoneum, mesentery and bladder presented metastasis. The treatment of this condition is not feasible with a delayed diagnosis due to its high aggressiveness and metastatic capacity. Such report demonstrates the importance of digital rectal examination and ultrasound exams, even in castrated animals for an early diagnosis of these neoplasms.