Original article Puerperal renal rhabdomyosarcoma: Case report and review of the literature Karen Meir, M.D. a , Marc Wygoda, M.D. b , Orna Reichman, M.D. c , Ofer N. Gofrit, M.D. d , Galina Pizov, M.D. a, * a Department of Pathology, Hadassah–Hebrew University Hospital, Jerusalem, Israel b Department of Oncology, Hadassah–Hebrew University Hospital, Jerusalem, Israel c Department of Obstetrics and Gynecology, Sha’are Zedek Medical Center, Jerusalem, Affiliated with the Faculty of Health Sciences, Ben-Gurion University of The Negev, Beer Sheba, Israel d Department of Urology, Hadassah–Hebrew University Hospital, Jerusalem, Israel Received 27 January 2005; received in revised form 19 May 2005; accepted 20 May 2005 Abstract Renal rhabdomyosarcoma is a rare malignant mesenchymal tumor with an aggressive clinical course. We describe the case of a 39-year-old woman with a large rhabdomyosarcoma of the left kidney serendipitously discovered ultrasonographically subsequent to cesarean section. To our knowledge, this is the first reported case of renal rhabdomyosarcoma during pregnancy. The importance of ultrasound examination in the differential diagnosis of gestational flank pain is discussed. © 2006 Elsevier Inc. All rights reserved. Keywords: Flank pain; Kidney; Pregnancy; Puerperium; Tumor 1. Introduction Renal rhabdomyosarcoma is a rare malignancy of mes- enchymal origin, often characterized by pleomorphic his- tology and a poor prognosis. In the largest reported review of 8 cases, the vast majority of patients were dead from disease over a relatively short follow-up of less than one year [1]. We report a case of renal rhabdomyosarcoma that presented as vague flank pain for which medical attention was not sought. The tumor was subsequently discovered in the puerperium. Macroscopic, histopathologic, immunohis- tochemical, and electron microscopic characteristics are outlined. Treatment for this rare cancer has yet to be stan- dardized, and the prognosis appears to be far worse in adults than in children. Gestational ureteral obstructions are more common than renal malignant tumors. Both entities justify the liberal use of ultrasound for investigation of flank pain during pregnancy [2]. 2. Case report A 39-year-old, gravida IV para III woman had ill-defined left flank pain during the latter half of her fourth pregnancy. The patient attributed the pain to pregnancy and did not seek medical attention. There was no gross hematuria. She was otherwise healthy. Her past medical history was significant for glucose-6-phosphate dehydrogenase deficiency. Her previous obstetric history revealed 3 normal pregnancies and deliveries. In the current pregnancy, nuchal translu- cency, detailed ultrasound, amniocentesis, and glucose chal- lenge test were normal. The patient was admitted in labor at 40 +6 weeks. Cesar- ean section (low segment transverse) was performed as a result of pathologic fetal heart rate tracing. A healthy female weighing 3945 g, with Apgar scores 9/9 was delivered. Lateral extension of the surgical incision was observed and repaired. Although postoperative ultrasound examination excluded hydronephrosis complicating the surgical exten- sion repair, a large, mixed-echoic mass located close to the left kidney was observed. Computerized tomography (CT) revealed a 10  12-cm richly vascular mass suspicious for malignancy at the posterolateral aspect of the left kidney. * Corresponding author. Tel.: +972-2-677-6529; fax: +972-2-642- 6268. E-mail address: Gpizov@hadassah.org.il (G. Pizov). Urologic Oncology: Seminars and Original Investigations 24 (2006) 40 – 43 1078-1439/06/$ – see front matter © 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.urolonc.2005.05.024