Renal myolipoosteoma: A distinctive lesion in a child.
We describe a distinctive renal tumor, a myolipoosteoma (MLO), in an 11-year-old boy who presented with a 6-month history of slight right flank intermittent pain. A gross examination revealed a well-defined, 5.5 cm mass with bone-like consistency. The lesion histologically featured an admixture of mature adipose tissue, spindle cells, and bony components. No atypia, mitotic activity, or pleomorphisms were observed in the tumor. The spindle cells were smooth muscle actin (SMA) and desmin positive but HMB45 and Melan-A negative, indicating that they were of a muscular nature and differed from that of angiomyolipoma (AML). The patient had no evidence of recurrence or metastasis 56 months postoperatively. We speculate that the present tumor, which to the best of our knowledge differs from all previously described tumors, is of nephrogenic rest (NR) origin and has a favorable prognosis.
Department of Pathology, Shandong Tumor Hospital, Jinan, Shandong, 250117, China. Electronic address: jinghong.biao@hotmail.com.
Hongbiao
H
Jing
Department of Pathology, The Sixth Hospital of Jinan, Zhangqiu, Shandong, 250200, China.
Tailing
T
Li
Department of Pathology, The Sixth Hospital of Jinan, Zhangqiu, Shandong, 250200, China.
Shujian
S
Zhai
Department of Pathology, The Sixth Hospital of Jinan, Zhangqiu, Shandong, 250200, China.
Yan
Y
Xi
Department of Pathology, The Sixth Hospital of Jinan, Zhangqiu, Shandong, 250200, China.
Qingda
Q
Meng
D018207:Angiomyolipoma / Q000473:pathology* / Q000601:surgery; D002648:Child; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008297:Male; D011379:Prognosis
Kidney; Myolipoosteoma; Nephrogenic rest; Pediatric; Tumor