the spleen is the greatest single mass of lymphatic tissue that lies between the left kidney , stomach and diaphragm ( 1 ) .
it has three surfaces : diaphragmatic , gastric and renal surface and the two borders : superior and inferior ( 1 ) .
this surface meets gastric and diaphragmatic surfaces respectively on the inferior border and a margin close to the splenic hilum ( 2 ) .
it plays vital roles in regard to blood storage , formation of lymphocyte and defense against foreign particles ( 3 ) .
accessory spleen is an ectopic splenic tissue develops result from the imperfect fusion of the splenic masses during embryonic life ( 4 ) .
it is found in 10 - 30 percent of the population ( 4 , 5 ) .
accessory spleens are found near the splenic hilum , in the gastrosplenic ligament , in the splenorenal ligament , in the mesentery , in the greater omentum , around the pancreatic tail and along vascular pedicle of the spleen , but rarely in the gonads ( 6 ) .
spleen primordium develops from the mesoderm of the dorsal mesogastrium in the fifth week of development .
accessory spleens rise from the dorsal mesogastrium as a result of failure fusion of the separate splenic nodules ( 4 ) . in the text book of moore s anatomy
has been mentioned the incidence of the accessory spleen was in 10% of the population ( 7 ) . in the usa , the incidence of accessory spleen was found at autopsy in 10 - 30% of american population ( 4 ) . in a european study
was found that the accessory spleen was present in 11% of patients undergoing abdominal ct - scan ( 8) . the incidence of accessory spleen ranged between 4.5% and 24.28% in asian population ( 9 - 11 ) .
hence , it is critical to correctly differentiate accessory spleens from tumors of the abdominal organs like adrenal tumor , pancreatic tumors or tumors of the retroperitoneal space ( 5 , 12 , 13 ) .
for example , when it is at pancreas region , it may mimic a pancreatic tumor .
in addition , the present of the accessory spleen is important to avoid a recurrence of symptoms of the disease when spleen should be removed in hematological disorders ( 5 , 12 , 13 ) .
hence , the objective of this study was evaluation the incidence of accessory spleen in iranian cadavers .
this study was carried out in the dissection hall of the forensic medicine organization , razavi khorasan province , from june 2014 to july 2015 .
the protocol of the research was approved by the ethics research committee of mashhad legal medicine organization .
sixty hundred and ninety three spleens ( 541 males , 152 females ) were excised from cadavers in the dissection hall of mashhad forensic medicine organization cadavers .
inclusion criteria were as follows : fresh iranian cadavers with no history of alcohol , poisoning or drug abuse , and no evidence of pathologic abnormality or injury to the spleen .
the presence of accessory spleens investigated near the splenic hilum , in the gastrosplenic ligament , in the splenorenal ligament , in the mesentery , in the greater omentum , and around the pancreatic tail .
, the spleen weight was measured with the help of an electronic weighing machine ( pand azma 3100 , iran ) .
a 20-year - old female , with no history of personal or family diseases that had been referred to autopsy laboratory of forensic medicine , khorasan razavi province , iran , for medicolegal autopsy on august 3 , 2014 .
the height , weight and bmi of cadaver were 162 m , 75 kg and 28.58 kg / m , respectively .
an accessory spleen in the splenic hilum , measuring 3.5/2.5 cm , was observed ( figure 1 ) .
( a - e ) are images of the spleens in case numbers 1- 5 , respectively .
one accessory spleen was found in a female cadaver ( age : 24 y , height : 165 m , weight : 69 kg , body mass index : 25.34 kg / m ) that was under examination to determine a cause of death .
the accessory spleen was located in the hilum with 3 cm long and 1.5 cm wide ( figure 1 ) .
a 42-year - old male , with no history of poisoning , alcohol or drug abuse and no evidence of trauma or abnormality of spleen that had been referred to the mashhad legal medicine on august 27 , 2014 .
the height , body weight and bmi of cadaver were 163 m , 59 kg and 22.21 kg / m , respectively .
its length was 2.5 cm and its width was 1.5 cm ( figure 2 ) .
an accessory spleen was observed in a female cadaver ( age : 34 y , height : 170 m , weight : 79 kg , bmi : 27.34 kg / m ) with no gross abnormality and injury of the spleen that needed autopsy .
the measurements using a vernier caliper showed that it was 2 cm in length and 1 cm in width ( figure 1 ) .
a 61-year - old male , with no history of pathologic abnormality or injury to the spleen was subjected to an autopsy on february 21 , 2015 , by the mashhad legal medicine , iran .
the values obtained for height , weight and bmi were 169 m , 68 kg and 23.81 kg / m , respectively .
the accessory spleen was measured 2.7 cm in length and 0.5 cm in width ( figure 1 ) .
the main finding of this study was the present of accessory spleen at the hilum of the spleen in five cadavers of razavi khorasan province , mashhad , iran . in the text book of snell s anatomy
has been reported the incidence of the accessory spleen 10 percent of the normal population and it may exist in the gastrosplenic ligament or in the lienorenal ligament ( 1 ) .
the incidence of accessory spleen was 10 - 30% of american population with a predominant site of the splenic hilum ( 4 ) . in another american study found that the accessory spleen was present in 15.6% of cases undergoing abdominal ct - scan ( 14 ) .
their length ranged between 4 and 29 mm and the range of their width was from 4 to 25 mm ( 14 ) .
similarly , the most common site of accessory spleen was near the hilum of the spleen and the maximum its width was 25 mm .
however , our findings showed that the incidence of accessory spleen was lower than that in this study ( 0.7% vs. 15.6% , respectively ) .
in addition , the maximum length of accessory spleen was more than that in american people .
romer and wiesner studied ct - examination of 1735 patients in switzerland , the accessory spleen was found in 11% of patients ( 8) . in a study by rayhan , the incidence of accessory spleen has reported 24.28% in bangladeshi people ( 9 ) . in another study in india ,
4.5% of the splenic samples exhibited an accessory spleen ( 10 ) . in a study by zhang and colleagues
have reported that most there is one accessory spleen in which was consistent with our finding ( 11 ) .
our results showed that the incidence of accessory spleen was less than that in indian population .
the limitation of this study was that there was not available data about accessory spleen in our population for comparison in this paper .
an accessory spleen has clinical significance in that they may result in diagnostic errors for the oncologists or the persistence of the symptoms after splenectomy .
hence , this report may help surgeons , oncologists , radiologists , and the anatomists regarding the incidence of the accessory spleen .
 aim : an accessory spleen is an additional tissue of the spleen that may be found near the spleen . it is a congenital anomaly of the spleen that its incidence has been reported 10 - 30% of the population . 
 hence , the objective of this study was evaluation the incidence of accessory spleen in iranian cadavers.method:sixty hundred and ninety three spleens ( 541 males , 152 females ) were excised from cadavers in the dissection hall of mashhad forensic medicine organization cadavers . 
 inclusion criteria were as follows : fresh iranian cadavers with no history of alcohol , poisoning or drug abuse , and no evidence of pathologic abnormality or injury to the spleen . 
 the presence of accessory spleens , its dimension and weight investigated in cadavers.results:during routine postmortem examination , five cases with an accessory spleen were found in the autopsy laboratory of mashhad legal medicine organization between june 2014 and july 2015 . of the cases , 3 were male and 2 were female . 
 the accessory spleens were observed at the splenic hilum . 
 the length of the accessory spleens ranged from 2 - 3.5 cm , while the range of width was between 0.5 and 2.5 cm . 
 the accessory spleens were confirmed by histological examination.conclusion:an accessory spleen has clinical importance in some locations . when an accessory spleen is situated in another site 
 , it may mimic some tumors such as pancreatic tumor and adrenal tumor . 
 in addition , accessory spleen may cause hyperplasia after splenectomy and be responsible for a recurrence of the hematological disorders . 
1. INTRODUCTION
2. METHOD
3. RESULTS
4. DISCUSSION
5. CONCLUSION