Sarcomatoid renal pelvis carcinoma: A case report

Abstract

Sarcomatoid carcinoma is a malignant tumor of epithelial origin, some of the cells of which are differentiated in a sarcomatoid direction and are highly invasive. Sarcomatoid renal pelvis carcinoma (SRPC) is very rare. This article reports on an elderly woman with SRPC and discusses the clinical and pathological features and prognosis of SRPC in the hope of providing a reference for the diagnosis and treatment of this disease.

1 Introduction

Sarcomatoid renal pelvis carcinoma (SRPC) is a rare malignant tumor with sarcomatoid changes in tumor morphology, which is more common in middle-aged and elderly people, and is more common in men than in women. . The clinical manifestations of SRPC are nonspecific, with gross hematuria being more common, and others being low back pain and abdominal pain. . Definitive diagnosis of the disease requires pathologic examination, especially immunohistochemical staining. Due to the extremely low prevalence of SRPC and the fact that most of the literature data are case reports, there are no standardized clinical treatment criteria. Here, we report a case of SRPC in a 67-year-old patient with final pathologic staging of pT2N0.

2 Case presentation

In July 2024, a 67-year-old woman was admitted to the hospital with “right-sided low back pain with gross hematuria for 1 month.” The patient had recurrent right-sided low back pain that persisted unrelieved for a month prior to admission, accompanied by gross hematuria throughout, with clots visible in the urine. Physical examination reveals that this patient has percussion tenderness over right kidney region, but no tenderness in the right ureteral area. The patient was hemodynamically stable and had no fever. Routine blood and urine tests showed a decrease in hemoglobin to 93 g/l, elevated urine white blood cells to 2926/μl, and elevated urine red blood cells to 328/l. Other laboratory tests did not show any significant difference: white blood cell count 5.72∗10^9/l, urine culture (−), creatinine 78 μmol/L. Abdominal unenhanced and contrast-enhanced CT suggests a possible neoplastic lesion of the right renal pelvis, accompanied by mild hydronephrosis of the right renal calyx ( Fig. 1 A and B). Magnetic resonance imaging of the kidney showed an irregular mass in the right renal pelvis with mild enhancement on enhancement scan, poorly defined lesion, involvement of the renal sinus and lateral renal parenchyma, and mild dilation of the right renal pelvis with hydronephrosis ( Fig. 1 C and D). The imaging diagnosis was malignant tumor of the right renal pelvis with hydronephrosis. In addition, three urine exfoliative cytology tests were negative.

On July 30, 2024, she underwent a cystoscopy with no evidence of bladder lesions, discoloration, or masses. He then underwent a right laparoscopic assisted radical nephroureterectomy(RUN) after a sleeve resection of the right ureteral opening. The specimen of the mass is hard and friable, and the cut surface is gray and fish-like. Pathology report: consistent with high-grade uroepithelial carcinoma, sarcomatoid type, with acute and chronic inflammation, the tumor invaded to the entire renal pelvis, no renal parenchyma or ureteral involvement was seen, and the pathological stage was T2N0. Immunohistochemical results: Tumor cells PCK(+), Vim(+), CK7(+), CK20(−), GATA-3(partially weak +), CKH(+), P40(−), P53(+ about 80 % mutant), SMA(partially+), Ki-67(+30–40 %), PAX-8(−) ( Fig. 2 ).