2012 Radiology Exam - Abdomen Case 1

Observations

• Prostate occupies approximately 50% of the sacropubic diameter
• Prostate margins are irregular
• Amorphous mineral opacities are present within the prostatic parenchyma
• Left kidney is enlarged with loss of normal shape
• Left kidney contains linear mineral opacities roughly conforming to the shape of the renal pelvis
• Mixed bronchial, unstructured interstitial, and structured interstitial pulmonary infiltrates are present within the caudal portion of the lung included in the study.

Synthesis

• Presence of a prostate of moderate size and irregular margination containing amorphous mineralization in a castrated male dog
• Finding most consistent with prostatic neoplasia with primary rule outs of adenocarcinoma or transitional cell carcinoma
• Enlarged left kidney with altered shape and internal mineralization.
• Ddx:
  • hydronephrosis related to obstruction at the level of the urinary trigone secondary to neoplastic invasion
  • metastasis of prostatic neoplasm
• Mixed pulmonary pattern including pulmonary nodules/masses consistent with metastasis of prostatic neoplasm

Case Management

• Abdominal ultrasound examination for examination and tissue sampling of the prostate and left kidney and for evaluation of regional lymph  nodes
• Thoracic radiographs to confirm suspected diagnosis of pulmonary metastasis

Challenges

• Failure to recognize that prostate size is abnormal in castrated male dog
• Failure to observe or ascribe appropriate significance to the mineral opacity in the prostate
• Failure to attempt to link left kidney abnormalities to the prostatic neoplasm.  On post mortem in this animal, the left kidney was both hydronephrotic and significantly replaced by neoplastic metastasis
• Failure to adequately evaluate or attach appropirate significance to pulmonary pattern
• Failure to completely evaluate the radiographic study.  Several candidates missed the primary diagnosis due to failure to evaluate the caudal abdomen in this 4 view radiographic study