Congenital anomalies of the spleen mimicking hematological disorders and solid tumors: a single-center experience of 2650 consecutive diagnostic laparoscopies.

Congenital anomalies of the spleen range from splenic lobulation, to accessory spleen to polysplenia. Though most of these anatomical variants have no clinical significance, an accessory spleen may simulate a tumor in the adrenal gland, pancreas, stomach or intestine. Alternatively, a missed accessory spleen may be the site of the relapse of a hematological disorder. We, therefore, assessed retrospectively: (i) the frequency of congenital anomalies of the spleen observed during 2650 consecutive laparoscopies and (ii) looked for possible misdiagnoses of the accessory spleen as hematological disorders or solid tumors located in the left upper quadrant of the abdomen. Congenital anomalies of the spleen were detected in 55 cases, accounting for 2.07%. Accessory spleens were observed in 44 patients (1.6%) and spleen lobulation in 11 (0.47%). An accessory spleen was the most common of the splenic anomalies. Among the 44 patients in whom an accessory spleen was discovered laparoscopically, the recognition of this anomaly prevented a relapse of a hematological disease in one case and avoided a useless exploratory laparotomy in the second, where the radiologist had interpreted this malformation as a space-occupying lesion. In the third case, the accessory spleen was initially misdiagnosed as a solid tumor of the pancreas, but was eventually recognized as a congenital anomaly by a second laparoscopy.