Xp11.2 translocation renal cell carcinoma with egg-shell calcification mimicking a benign renal tumour: A case report

Abstract

Abstract. The present study reports the case of a 20-year-old female who was identified to have a left renal angiomyolipoma (AML) with hemorrhage. Following temporary conservative observation, the patient received continuous ultrasonic follow-up. Due to the rapid growth of the lesion, further examinations were performed. Computed tomography (CT) plain scans revealed a partly high-density mass with marginal egg-shell calcification. Enhanced CT revealed a solid tumor with a rich blood supply. Since no fats were detected, the possibility of a typical AML was excluded, but the diagnoses of epithelioid AML or renal cancer were considered. Finally, the left kidney was partially excised laparoscopically. The intraoperative frozen section indicated a diagnosis of renal cell carcinoma (RCC). The left kidney was subsequently radically excised. . Routine histopathological and immunohistochemical tests confirmed that the lesion was an RCC with an Xp11.2 translocation. The present study introduces the pitfalls in the diagnosis of Xp11.2 translocation RCC, which is a rare RCC subtype accompanied with uncommon imaging manifestations. The study suggests that when a rapidly-growing AML is detected by ultrasound, renal cancer with marginal calcification should be considered. Moreover, although egg-shell calcification mostly occurs in benign renal lesions, further examinations, such as enhanced CT, are recommended for identifying the nature of the masses and excluding the possibility of malignant tumors.

Multidetector CT Characteristics of Fumarate Hydratase-Deficient Renal Cell Carcinoma and Papillary Type II Renal Cell Carcinoma

“…Typically, the size of tubulocystic RCCs (TCRCC) is small, and approximately 40.0% of them are smaller than 2 cm [ 18 ], unlike the FH-deficient RCC observed in our cases. As reported in the literature, cystic pattern and rim-like or egg-shell calcification are common in Xp11.2/TFE RCC [ 25 26 27 ]. However, the probability of a polycystic shape was higher, and typical calcification was relatively rare in FH-deficient RCC.…”

Renal Tumors of Childhood: Radiologic-Pathologic Correlation Part 2. The 2nd Decade:From the Radiologic Pathology Archives

“…There is a paucity of literature describing the appearance of translocation RCC at US. In case reports, the tumor has been described as heterogeneous, with echogenic calcifications and benign-appearing "egg-shell" calcifications (Figs 2, 3) (16,17). To minimize the risk from ionizing radiation, nonenhanced and multiphase CT examinations typically are not performed in children.…”

Factors Associated with Survival From Xp11.2 Translocation Renal Cell Carcinoma Diagnosis—A Systematic Review and Pooled Analysis

“…After the screen of abstracts, 152 articles were considered to be relevant reports. After reviewing these articles, we found 80 that reported histopathologically confirmed Xp11.2 tRCC and fulfilled the inclusion criteria (Figure 1), giving a total of 415 patients [2], [8][9][10], [11][12][13][14][15][16][17][18][19][20], [21][22][23][24][25][26][27][28][29][30], [31][32][33][34][35][36][37][38][39][40], [41][42][43][44][45][46][47][48][49][50], [51][52][53][54][55]…”