Metastatic parenchymal renal squamous cell carcinoma with hypercalcemia.

Abstract

Renal tumors originated from renal parenchyme or renal pelvis with different histological subtypes. The most common observed malign renal tumors are clear cell renal cell carcinoma (CCRCC), multilocular cystic renal cell carcinoma (MCRCC), papillary renal cell carcinoma (PRCC), chromophobe RCC and carcinoma of the collecting ducts of Bellini, respectively [1]. Primary squamous cell carcinoma (SCC) of the renal parenchyme or renal pelvis is very unusual and rare entity which accounts less than 1 % of renal malign tumors [2]. To our knowledge, there are only two renal parenchymal SCC cases reported until today [3]. This letter presents a case of metastatic renal parenchymal squamous cell carcinoma associated with hypercalcemia, which is not reported until now. A 53-year-old male patient was admitted to our clinic with severe left-sided flank pain and intermittent hematuria. The patient was non-smoker and had a history of intermittent flank pain due to nephrolithiasis. Laboratory evaluation revealed mild anemia and hypercalcemia with microscopic hematuria. Serum calcium level was 13.2 mg/ dl (normal range 8.6–10.2 mg/dl) and serum albumin was 2.9 g/dl (normal range 3.5–4.5 mg/dl) with suppressed parathyroid hormone levels and normal renal functions. Corrected calcium level was calculated as 14.1 mg/dl. By intense hydration and zoledronic acid treatment, serum calcium level was corrected to normal levels. Thoracic and abdominal computed tomography (CT) was performed, and multiple metastatic nodular lesions in both lung and multilocular metastatic hypodense masses with the largest 61 9 55 mm in the right posterior lobe of liver were revealed. Additionally, prominent parenchymal mass in the right kidney and perirenal multiple lymphadenopathies with the biggest size of 18 9 33 mm were found. The patient underwent cytoreductive nephrectomy and right hemicolectomy due to direct tumoral invasion. On the gross examination, the tumor measuring 6.2 9 4.2 9 3.1 cm diameter with multiple calculus was seemed as ulcerative and necrotic confined to the upper pole of right kidney. No tumoral invasion to the renal pelvis was found. Pathological examination of the surgical material revealed moderately differentiated SCC in the renal parenchyma directly invasive to the serosal surface of the right colon without mucosal involvement. Then, due to the extensive disease, patient was treated with six cycles of gemcitabine and carboplatin regimen every 3 weeks plus zoledronic acid. After six cycles of chemotherapy, the patient was progressively deteriorated and died. Squamous cell carcinomas are associated with chronic inflammatory conditions such as renal calculi, recurrent urinary tract infections and schistosomiasis. So, a patient with SCC should be evaluated for such predisposing risk factors that associated with squamous metaplasia and subsequently SCC [4]. In our case, renal calculi were established in both radiologic studies and gross examination of the surgical material. Due to the renal pelvis SCCs tend to be invasive and sessile, the diagnosis of the renal parenchymal SCC should be confirmed with the evaluation Y. Acikgoz Department of Internal Medicine, Ankara Numune Education and Research Hospital, Ankara, Turkey