Urinary Tract Pathology Case Studies


CASE 5: Renal cell carcinoma; Chronic pyelonephritis


Clinical History:

A 54-year-old man noted dull left flank pain that was becoming more constant over the past few weeks. He had constant dull left flank pain. A urinalysis dipstick examination showed 4+ blood and microscopic examination showed 50-75 RBC's/hpf. A CT scan of the abdomen revealed a large left renal mass that appeared solid. A left radical nephrectomy was performed.
  1. What is the diagnosis of the neoplasm?

    2. This is a renal cell carcinoma. Note the characeristic clear cell pattern. The increased glycogen and lipid in these cells imparts the grossly yellow colour to the cut surface of this neoplasm.

  2. Name some paraneoplastic syndromes associated with this lesion.

    3. Paraneoplastic syndromes associated with renal cell carcinomas include: polycythemia, hypercalcemia, hypertension, femininization, masculinization, Cushing's syndrome, amyloidosis, leukemoid reactions (very high white cell count).

  3. What is the natural history of this lesion?

    4. What does the size of the tumor tell you? Larger renal cell carcinomas have a higher stage and are more likely to act aggressively, particularly if there were evidence for invasion. Typical initial sites for invasion include the renal capsule and the renal vein. Renal cell carcinomas may metastasize just about anywhere. Sometimes they can have solitary metastases which, if resected, result in a cure. Metastases may be so slow growing that they appear 1 to 2 decades after the primary is discovered. Thus, they can be somewhat unpredictable.

  4. What additional diagnosis can you make in the kidney tissue adjacent to the neoplasm and what caused it?

    5. Adjacent renal parenchyma shows infiltrates of lymphocytes and plasma cells consistent with chronic pyelonephritis, probably consequent to obstruction by the tumor.