Leukemoid reaction in sarcomatoid renal cell carcinoma: a two-case report

A 36 year old woman presented with left flank pain for one month. The patient was admitted to the First Affiliated Hospital of Wenzhou Medical University and underwent serial examinations. Physical examination showed a left flank mass with tenderness. An abdominal computed tomography (CT) scan showed a mass measuring 8 × 10 cm in the left kidney (Figure 1A). Her initial white blood cell (WBC) count was 48 × 10⁹/l, she did not complain of fever, and her bone marrow smear did not show myeloproliferative process. A septic workup, including chest x-ray, blood culture, and urine culture were all negative. She underwent radical nephrectomy and the pathologic diagnosis was SRCC (Figure 2A). No complication developed and the course of treatment was uneventful. However, the WBC count gradually increased (Figure 3A) and the body temperature was high (37.9 to 40.5°C). She was treated with systemic antibiotics and the temperature decreased but the WBC count remained high. Due to the high WBC count, a workup for chronic myeloid leukemia (CML) was initiated. The lactic dehydrogenase (LDH) level was 351. The leukocyte alkaline phosphatase (LAP) score was 280. A peripheral smear showed numerous segmented neutrophils and bands. A bone marrow biopsy also provided no evidence supporting either a hematological neoplasia, or the presence of infiltration by tumor cells. Cytogenetic studies were normal. A PCR(Polymerase Chain Reaction) for BCR-ABL fusion transcript was negative. A diagnosis of a leukemoid reaction was confirmed and she died of multiple organ failure shortly there after at six weeks postoperatively.

The patient, a 56 year old male, complained about more than half a month’s history of right flank pain and fever. He had no systemic and lower urinary tract symptoms and was admitted to the First Affiliated Hospital of Wenzhou Medical University for further examinations. The patient started with a high fever (38.5 to 41.0°C). His first WBC count was 26.9 × 10⁹/L. A tender, palpable right flank mass with an acute percussion pain was detected during a physical examination. His CT scan showed a solid hypo dense lesion in the right kidney measuring 7 × 10 cm (Figure 1B). Meanwhile, a right renal tumor was identified with no evidence of extra-renal extension or distant metastases. An open right radical nephrectomy was performed via a supra-11th rib right flank incision. The tumor was pathologically diagnosed as SRCC (Figure 2B). Postoperative recovery was uncomplicated and white blood cell decreased gradually to the normal range. However, two weeks later after the patient was discharged, he presented with a high fever again once more. Even though broad-spectrum antibiotics were administered without delay, the increasing speed of the WBC count was dramatic (Figure 3B). Leukemoid reaction was established and the patient died of multiple organ failure less than 50 days after the operation.