Leiomyoma of the Kidney: Presentation of 4 New Cases and The Role of Computerized Tomography

Abstract

Renal leiomyoma is a challenging diagnostic and therapeutic condition. It is clinically similar in presentation and radiographic appearance to its malignant counterpart, leiomyosarcoma. We review 30 cases of clinically diagnosed leiomyoma of the kidney from the literature, including 4 new cases with emphasis on the computerized tomography findings. Computerized tomography may locate a renal leiomyoma serendipitously in an asymptomatic patient. If the lesion is peripheral or in the parapelvic area and a plane can be seen between the tumor and kidney a capsular tumor, such as a leiomyoma of the kidney, might be considered in addition to the more common renal cell carcinoma. Renal leiomyomas have a variable radiographic pattern from that of a pure cystic to a mixed solid/cystic to an entirely solid lesion. Renal leiomyomas usually are sharply demarcated from the surroundings. Although computerized tomography cannot distinguish a renal leiomyoma from other benign or malignant renal processes the presence of invasion can virtually eliminate this benign tumor as a diagnosis. Since a preoperative diagnosis cannot be made, management involves renal exploration and radical nephrectomy in the larger lesions with a renal-sparing operation possible in selected cases. After treatment patients have a uniformly excellent prognosis.

Renal leiomyoma: Case report and literature review

“…7 Renal leiomyoma is a rare benign tumour with autoptic evidence of 4.2% to 5.2%. 8 In a recent review developed by the J. B. Brady Urological Institute (Baltimore Maryland), in a period over 10 years on 1030 nephrectomies performed, renal leiomyomas represented 1.5% of benign renal tumours and 0.3% of overall tumours treated.…”

“…More than half of the cases present pain and a palpable mass and 20% present hematuria. 8 Steiner and colleagues divided renal leiomyomas into two groups on the basis of the clinical features: (1) small tumours, asymptomatic, sometimes multifocal, incidentally detected in autopsy or after radical nephrectomy and (2) big tumours, often singular lesion, clinically manifested by symptoms/ signs as pain or abdominal palpable mass. However, during last 15 years, the widespread use of ultrasonography and CT has increased the detection of clinically asymptomatic renal leiomyomas.…”

“…In suspicious cases, radical nephrectomy is the typical approach with an excellent prognosis. 8 In cases of small lesions (≤4 cm), it is possible opt for conservative surgery. A further option for smaller lesions is renal biopsy, although this solution is still controversial.…”

“…8 In addition, lesions larger than 12 cm may have cystic degeneration and hemorrhagic areas in 17% and 27% of cases, respectively. The cystic degeneration is not necessarily associated with sarcomatoid degeneration.…”

“…8 As of today, the biggest renal leiomyoma is 57.5 cm with a weight of 37.2 kg. 12 Macroscopically the renal leiomyoma is described as a white or red peripheral lesion, well-defined, with a solid aspect and elastic consistence.…”