Case Report Complete Regression of a Congenital Splenic Cyst Yanki Çelik Yilmazer, MD,1 Ayşe Erden, MD2 1 2 Department of Radiology, Zübeyde Hanim Maternity Hospital, Ankara 06080, Turkey Department of Radiology, Türkiye Yüksek Ihtisas Hospital, Ankara 06500, Turkey Received 25 August 1997; accepted 16 September 1997 ABSTRACT: We report a congenital splenic cyst that was revealed by prenatal sonography at 31 weeks’ gestation. Serial prenatal sonographic examinations showed a slight enlargement of the cyst. However, sonography performed when the infant was 7 months of age showed the cyst had spontaneously and completely regressed. We recommend that practitioners adopt a more conservative approach in such infants, one that includes follow-up sonographic examinations, rather than instituting interventional treatment. © 1998 John Wiley & Sons, Inc. J Clin Ultrasound 26:223–224, 1998. Keywords: splenic cyst; ultrasonography C ongenital splenic cysts are uncommon. To the best of our knowledge, only 9 cases have been reported that were identified prenatally by sonography.1–4 We report a case of congenital splenic cyst that was diagnosed by sonography at 31 weeks’ gestation and followed postnatally until the cyst had completely regressed. CASE REPORT A 12-mm, round cystic lesion located in the left upper quadrant of the fetus’s abdomen was detected by sonography in a 26-year-old woman (gravida 1, para 0) when she was first examined at our clinic at 31 weeks’ gestation. The cystic lesion was noted to be separate from the stomach and left kidney and was believed to be located in either the spleen or the left adrenal gland. No other fetal or pregnancy-related abnormality was detected. At 35 weeks’ gestation, the size and Correspondence to: Y. Ç. Yilmazer, Hüseyin Onat Sokak 11/2, A. Ayranci Ankara, 06540, Turkey © 1998 John Wiley & Sons, Inc. CCC 0091-2751/98/040223-02 shape of the cystic lesion were unchanged. Sonographic examination performed at 38 weeks’ gestation, however, showed that the cystic lesion had enlarged and was now 14 × 14 mm (Figure 1A). At 40 weeks’ gestation, the patient gave birth vaginally to a viable female infant weighing 3,100 g. Sonography revealed a unilocular cyst in the spleen of the newborn. The cyst had regular contours and a size of 17 × 16 mm. Sonography performed when the infant was 2 months of age showed no change in the size of the cyst (Figure 1B). Sonography at 4 months showed the cyst had shrunk to 13 × 10 mm and had become ovoid. Sonography at 7 months showed that the cyst had completely regressed. DISCUSSION Most congenital splenic cysts that have been described in the literature have been either very large or symptomatic when discovered, and to prevent infection, rupture, or hemorrhage, the therapy of choice has been an interventional procedure, such as partial or total splenectomy, cystectomy, laparoscopic puncture, or sonographically guided fine-needle aspiration.1 A splenic cyst should also be considered in the differential diagnosis of cystic lesions seen in the fetal left upper quadrant. With the advent of high-resolution ultrasound equipment and the increasingly frequent prenatal use of sonography, it has become possible to detect small splenic cysts in fetuses. The prenatal diagnosis of a splenic cyst on the basis of sonographic findings was first reported in 1988,1 and 9 such splenic cysts have been reported to date.1–4 This ability to diagnose these asymptomatic but potentially serious lesions prenatally permits optimal management.2 223 YILMAZER AND ERDEN FIGURE 1. Congenital splenic cyst. (A) Sonogram at 38 weeks’ gestation shows a cystic lesion (cursors) measuring 14 × 14 mm in the left upper quadrant of the fetal abdomen. (B) Sonogram at 2 months of age shows a cyst (cursors) measuring 17 × 16 mm. Scans obtained at 7 months showed complete regression. Spontaneous postnatal regression of a splenic cyst was first reported in 1995.3 In our case, the cyst was found to have shrunk by the 4th month postnatally and to have completely regressed by the 7th month. Because a splenic cyst may spontaneously regress and ultimately disappear, we suggest that a more conservative approach be adopted instead of interventional procedures, with their attendant risk of complications. However, infants with these lesions should be carefully followed up because subsequent cyst enlargement would mandate interventional therapy to prevent cystic rupture or hemorrhage. 224 REFERENCES 1. Lichman JP, Miller EI: Prenatal ultrasonic diagnosis of splenic cyst. J Ultrasound Med 1988;7:637. 2. Stiller RJ, de Regt RH, Choy OG: Antenatal diagnosis of fetal splenic cyst: a case report. J Reprod Med 1991;36:320. 3. Garel C, Hassan M: Foetal and neonatal splenic cyst-like lesions: US follow-up of seven cases. Pediatr Radiol 1995;25:360. 4. Okada M, Hata T, Ariyuki Y, et al: Fetal splenic cyst: change in size and shape with advancing menstrual age. J Clin Ultrasound 1995;23:204.