Accessory spleens at autopsy.

Accessory spleens (AS) may be formed during embryonic development when some of the cells from the developing spleen are deposited along the path from the midline, where the spleen forms, over to its final location on the left side of the abdomen. An accessory spleen is usually near the spleen's hilum, but it may be embedded partly or wholly in the tail of the pancreas. The aim of this study was to investigate the incidence and distribution of AS during routine forensic autopsies. AS were investigated in 720 consecutive autopsy cases. Fifty-four AS were found in 48 (6.7%) cases. AS were found in hilum of the main spleen in 28 cases, the great omentum in 13 cases, the pancreas in 5 cases, and the pelvis in 2 cases. There were two AS in two cases and three AS in another two cases. Awareness of the possible presence of AS is important because when splenectomy is performed for some conditions such as immune thrombocytopenic purpura, failure to remove the AS may result in the failure of the condition to resolve. Additionally, during medical imaging, AS may be confused for enlarged lymph nodes or neoplastic growths. In conclusion, autopsy series are useful for determining the incidences and the other features of AS in different populations, in addition to those studies using CT scans and those studies obtained during laparoscopic or open surgeries.