Intrapancreatic Accessory Spleen Mimicking Endocrine Tumor of the Pancreas: Case Report and Review of the Literature

Accessory spleen is an anomaly that is observed in about 10% of individuals by the autopsy study, and most accessory spleens are located close to the splenic hilum. Although accessory spleen is a frequently encountered entity, intrapancreatic accessory spleen (IPAS) is rarely recognized radiologically and is sometimes mistaken for another type of pancreatic neoplasm. Only 10 IPAS cases surgically resected as solid pancreatic mass have been reported in the English literature. We herein report a case of IPAS mimicking an endocrine tumor of the pancreas and review of the literature.     

Post-splenectomy intrapancreatic accessory spleen mimicking endocrine tumor of the pancreas

INTRODUCTION

Intrapancreatic accessory spleen is an uncommon congenital abnormality of the spleen with no indication for surgical intervention. Among the few cases reported, IPAS coexisted with a normal spleen. We here report the first case of IPAS arising a couple years after splenectomy with the appearance of an endocrine tumor of the pancreas.

PRESENTATION OF CASE

A 62-year-old female presented with a one-week history of left upper quadrant discomfort. She had splenectomy for the treatment of hypersplenism caused by cirrhotic portal hypertension two years before this admission. Her physical examination was unremarkable and laboratory data was within the normal range. Both the ultrasonography and magnetic resonance image revealed a small oval-shaped mass in the tail of her pancreas with the diameter 2 cm or less. A distal pancreatectomy was performed for the suspection of malignant neuroendocrine tumor of the pancreas. An intrapancreatic accessory spleen was confirmed by the pathologic examination.

DISCUSSION

Intrapancreatic accessory spleen is one kind of congenital ectopic spleen without indication for operative intervention. We present the case to support that intrapancreatic accessory spleen may enlarge through a compensatory mechanism, and raise the awareness of this intrapacreatic entity to avoid unnecessary surgical operation.

CONCLUSION

IPAS should be highly considered as a differential diagnosis while the lesion is no more than 2.5 cm in diameter and/or other accessory spleens show around the splenic hilum.     

Epidermoid cyst in an intrapancreatic accessory spleen: a case report

Ectopic splenic tissue in the abdominal cavity is a common entity, with a reported incidence of 10% in the general population. However, an intrapancreatic accessory spleen is a rare disease, and moreover cyst formation in it is exceedingly rare. A 58-year-old woman with a 25-mm multilocular cyst in the tail of the pancreas detected incidentally by ultrasonography was admitted for further evaluation. Because malignancy could not be ruled out, a spleen-preserving distal pancreatectomy was performed. The cut surface of the surgical specimen showed a multilocular cyst surrounded by brown solid tissue resembling normal spleen. Pathological examination revealed it was stratified squamous epithelium and was surrounded by splenic tissue. The final pathological diagnosis was epidermoid cyst in an accessory spleen in the pancreas. This cyst has no characteristic features on diagnostic imaging. Consequently, it is not possible to make a definite preoperative diagnosis in most cases. Epidermoid cyst in intrapancreatic splenic tissue is another lesion to be considered in the differential diagnosis of pancreatic tail tumors.     

Intrapancreatic accessory spleen: a differential diagnosis of pancreatic tumour

BACKGROUND: According to autoptic studies, accessory spleens may be found in 10-15% of the population and most of them are usually located at or near the splenic hilum. Only in 1-2% they are located in the pancreatic tail. We report a rare case of intrapancreatic accessory spleen which radiologically mimicked a tumor in the tail of the pancreas. PATIENT: A 54-year-old man was diagnosed with a tumor at the pancreatic tail. In the preoperative computed tomography (CT), there was a lesion (2.6 cm in diameter) in the pancreatic tail and two locoregional lesions (1 and 1.5 cm in diameter), which had intensive contrast enhancement. The diagnosis of a nonfunctioning endocrine pancreatic tail carcinoma with lymph node metastasis was made. RESULTS: Intraoperative examination showed two accessory spleens nearby the pancreatic tail. As pancreatic cancer could not be excluded because of the local findings, an oncological left pancreatectomy was performed. Histological examination excluded cancer and revealed an intrapancreatic accessory spleen and two accessory spleens nearby the pancreatic tail. CONCLUSION: Intrapancreatic accessory spleen should be included in the differential diagnosis of pancreatic neoplasm.     

Left-sided portal hypertension caused by serous cystadenoma of the pancreas: Report of a case

We report a case of serous cystadenoma of pancreas causing left-sided portal hypertension and gastric varices. A 68-year-old man was admitted for treatment of a pancreatic body tumor. Contrast-enhanced computed tomography (CT) showed a honeycombed cystic mass. A celiac angiogram showed a hypervascular tumor supplied mainly by a dilated splenic artery and dorsal pancreatic artery. In the venous phase, the patent splenic vein had a large hepatopetal collateral vein via the coronary gastric vein. Upper gastrointestinal endoscopy showed isolated varices of the gastric fundus. We made a preoperative diagnosis of a serous cystic tumor of the pancreas with left-sided portal hypertension and performed distal pancreatectomy with splenectomy. The resected tumor was 8 cm in diameter and had a typical honeycombed microcystic pattern with central stellate scarring. The spleen was not enlarged. Histopathological examination confirmed a diagnosis of serous cystadenoma without any sign of malignancy. Postoperative endoscopy showed disappearance of the gastric varices.     

Pancreatic adenosquamous carcinoma presenting as splenic rupture: report of a case

A 58-year-old female patient presented with the sudden onset of left upper quadrant pain. The physical examination revealed the presence of shock status. Abdominal computed tomography revealed splenomegaly with a huge mass inside the spleen, and massive fluid collection in the abdominal cavity. After splenic artery embolization, laparotomy was performed. The operative findings revealed intra-abdominal hemorrhage and rupture of the lower pole of the spleen. Furthermore, a palpable solid mass was observed at the splenic hilum, and distal pancreatectomy with splenectomy was performed. The macroscopic findings revealed a pancreatic tail tumor at the splenic hilum directly invading the splenic parenchyma. Microscopic examinations showed the tumor to consist of squamous cell carcinoma. Furthermore, old and new thrombi were observed inside small splenic arteries. These findings were considered to represent invasion of pancreatic adenosquamous carcinoma to the spleen, and rupture of the spleen was attributed to splenic ischemia resulting from cancer invasion and splenic vein obstruction.     

Laparoscopic resection of an epidermoid cyst originating from an intrapancreatic accessory spleen: Report of a case

A 67-year-old man underwent an investigation of epigastric pain and weight loss. Preoperative imaging findings suggested the presence of a tumor, which developed as an epidermoid cyst and originated from an intrapancreatic accessory spleen; however, the possibility of malignancy could not be ruled out. We therefore performed a laparoscopic-assisted distal pancreatectomy with a splenectomy for both diagnostic and treatment purposes. Five laparoscopic ports were created. After the spleen and pancreatic tail were dissected from the retroperitoneum laparoscopically, they were pulled out through a 7-cm left subcostal incision and resected with an endoscopic linear stapler. The operative time was 227 min and the blood loss was 400 ml. The postoperative course was uneventful. The final pathological diagnosis was in agreement with the preoperative diagnosis. This case demonstrates that the minimally invasive approach of laparoscopic surgery can be used safely and successfully for difficult-to-diagnose pancreatic tumors. This is the first report describing a laparoscopic resection of an epidermoid cyst originating from an intrapancreatic accessory spleen.     

Intrapancreatic accessory spleen imitating a pancreatic neoplasm

Accessory spleens are present in 10% of population and are formed during embryonic development. Besides the splenic hilum, the next most frequent localization of accessory spleens is the pancreatic tail. Intrapancreatic accessory spleens are usually diagnosed occasionally and make diagnostic difficulty because they imitate a pancreatic neoplasm. We present the case of a 61-year old woman with a mass in the pancreatic tail, diagnosed by computed tomography. The patient was operated with suspicion of neuroendocrine tumor. Postoperative histopathological examination revealed the intrapancreatic accessory spleen. We present possibilities of differential diagnosis.     

Epidermoid cyst originating from an intrapancreatic accessory spleen

We report a rare case of an epidermoid cyst originating from an intrapancreatic accessory spleen, in a 40-year-old Japanese man with no clinical symptoms. A cystic tumor in the pancreatic tail was detected incidentally by abdominal ultrasonography. The patient was referred to the KKR Tachikawa Hospital for further examination of the tumor. Preoperative imaging findings suggested that the tumor was an epidermoid cyst originating from an intrapancreatic accessory spleen. On both pre-and post-contrast computed tomography and magnetic resonance images, the solid compartment of the tumor had the same X-ray attenuation and intensity as the spleen. Upon surgical excision, the mass consisted of solid and cystic components that were macroscopically evident on the preoperative images. Microscopic analysis revealed that the solid component was an accessory spleen in the pancreatic tail, whereas the cystic component was lined with stratified epithelium representative of an epidermoid cyst. This is the thirteenth report (in English) of an epidermoid cyst originating from an intrapancreatic accessory spleen, and the first case to be diagnosed prior to surgery.     

Intrapancreatic accessory spleen: A case report and review of the literature

We present the case of a 26 year old male who was found to have a mass in the tail of the pancreas on an ultrasound scan. The lesion was suspicious for a non-functioning pancreatic neuroendocrine tumour (PNET) and so he underwent distal pancreatectomy. Pathology revealed this to be an intrapancreatic accessory spleen (IPAS). This is a rare entity, and the literature on this subject is reviewed. A lesion in the pancreas that enhances in a manner similar to the spleen, whether the contrast is used in the setting of a Contrast Enhanced Ultrasound, a contrast enhanced CT scan, or a gadolinium enhanced MRI scan, is suggestive of IPAS. Nonetheless, the majority of these rare lesions are likely to be surgically excised rather than observed due to the similar appearance to PNET.     

Spleen-preserving laparoscopic distal pancreatectomy after division of the splenic vessels

A 37-year-old woman with a history of syncope was hospitalized with a diagnosis of hypoglycemia due to insulinoma. Computed tomography (CT) and magnetic resonance imaging revealed an enhanced solid mass, 1.5 cm in diameter, at the tail of the pancreas. Angiography via the splenic artery revealed a hypervascular mass. Because the tumor was located deep in the pancreatic parenchyma, laparoscopic distal pancreatectomy was performed. The pancreas was exposed by dissecting the greater omentum, and the tumor was located by intraoperative ultrasonography. After division of the splenic artery, the pancreas, main pancreatic duct, and splenic vein were transected with an endoscopic linear stapler. The pancreatic pedicle was divided at the splenic hilum to preserve the spleen. The postoperative course was uneventful except for the appearance of splenic infarction on a CT scan 2 weeks after surgery but without any overt symptoms. Spleen-preserving laparoscopic distal pancreatectomy by division of splenic vessels is a feasible treatment option for benign pancreatic disease.     

胰腺异位副脾的CT与MRI检查特征

胰腺异位副脾（IPAS）临床少见,其影像学表现易与胰腺实质性肿瘤相混淆,总结其CT和MRI检查特征,将有助于提高对该病的诊断与鉴别诊断水平,避免不必要的手术。2007年8月至2012年8月宁波大学医学院附属医院和第二军医大学长海医院分别收治的5例和3例IPAS患者。8例患者均行CT检查。7例患者同时行MRI检查,其中5例行磁共振弥散加权成像（DWI）检查。其结果显示：8例患者病灶均位于胰尾,4例呈卵圆形,3例呈类圆形、1例呈类三角形,最长径为（2．3±1．0）em,最短径为（1．4±0．6）cm。CT平扫：8例患者病灶密度与原位脾相近。CT增强扫描检查：动脉期：3例患者病灶呈均匀强化,5例患者病灶呈斑马纹样强化;门静脉期：8例患者病灶强化程度趋向均匀;延迟期：8例患者病灶强化程度均下降。三期动态增强扫描中,8例患者病灶强化方式与原位脾基本一致,7例患者病灶强化程度高于胰腺实质。MRI检查：7例患者病灶在T1WI、T2WI的信号强度与原位脾一致;在动态增强扫描各期6例患者病灶强化程度均高于胰腺实质。DWI检查：b=600s／mm2时,病灶呈显著高信号,ADC600值为（0．868±0．046）mm2／s,与相应原位脾的ADC600值（0．870±0．045）mm。／s比较,差异无统计学意义（t=0．522,P〉0．05）。2例患者合并肝硬化,其中1例伴原发性肝癌。2例患者发现脾脏周围存在其他副脾。因此,当影像学检查发现胰尾的类圆形或卵圆形病灶边界清楚,其密度、信号强度与脾脏相近时应考虑IPAS。CT和（或）MRI动态增强扫描联合DWI检查对IPAS的诊断具有重要价值。     

Laparoscopic Spleen-Preserving Pancreatic Tail Resection for an Intrapancreatic Accessory Spleen Mimicking a Nonfunctioning Endocrine Tumor: Report of a Case

Laparoscopic surgery is now performed for several pancreatic disorders, such as benign tumors of the pancreatic body or tail, which are a good indication for laparoscopic resection. However, the risk of pancreatic fistula after distal pancreatectomy, performed laparoscopically or by open surgery, is a topic of debate. We report the case of a 61-year-old man in whom a routine follow-up computed tomography (CT) scan showed a solid, well-defined mass, 1.5cm in diameter, in the pancreatic tail. The mass was homogeneously enhanced from the early phase to the super-delayed phase on enhanced CT. We suspected a nonfunctioning endocrine tumor of the pancreas, and surgery was performed laparoscopically. After dissecting the pancreatic tail away from the splenic hilum and the splenic vessels, it was resected using only a linear stapler. The histological diagnosis was an intrapancreatic accessory spleen. The patient was discharged on postoperative day 14, but was readmitted 6 days later because of a pancreatic fistula, which was treated by CT-guided percutaneous drainage.     

Resectable carcinoma of the pancreatic head developing 7 years and 4 months after distal pancreatectomy for carcinoma of the pancreatic tail

A 67-year-old woman was referred with an abnormal finding on an abdominal echogram but presented with no symptoms; a pancreatic tail tumor was detected by ultrasonography. Biochemical examinations showed slight elevation of serum carcinoembryonic antigen level. The lesion was resected by tail and body pancreatectomy and her postoperative course was uneventful. Seven years and 4 months after the initial operation, however, her serum level of carbohydrate antigen 19-9 was found to be elevated, and a recurrence of pancreatic cancer was suspected. Examinations revealed a mass in the head of the remnant pancreas. The lesion was radically resected by total remnant pancreatectomy. Histological examinations showed that the initial tumor was a well differentiated tubular adenocarcinoma, while the second tumor was characterized as a moderately differentiated tubular adenocarcinoma. The surgical margins of the distal pancreatectomy specimen were free of atypical cells. Therefore, the position of the second lesion diminished the likelihood that it had developed by intrapancreatic metastasis. This suggests that the second carcinoma in the head of the pancreas may have been a second primary lesion. Received for publication on June 1, 1999; accepted on Sept. 20, 1999     

Conservation of the spleen with distal pancreatectomy

This report describes a rapid, easy, and safe means of saving the spleen while resecting or fully mobilizing the pancreatic tail. The pancreas is separated from the spleen by dividing the splenic artery and vein distal to the tip of the pancreas. The spleen survives on the short gastric vessels, which are carefully preserved. The technique has been applied successfully in 22 of 25 consecutive patients with chronic pancreatitis (n = 13), acute pancreatitis and pancreatic necrosis (n = 3), cystic neoplasm of the pancreas (n = 4), islet cell tumor (n = 2), and ductal adenocarcinoma (n = 3). The spleen could not be saved in three patients because of splenic hilar involvement by tumor or scar. Normal postoperative blood cell counts and spleen scans proved splenic viability and function. There was only one complication, a late splenic abscess that developed in a spleen of twice-normal size. It is concluded that in most instances the distal pancreas can be mobilized for resection or inspection without the need for splenectomy. Splenomegaly may be a contraindication because the short-vessel gastric blood supply may be inadequate to nourish the increased tissue mass. The technique is applicable to the treatment of pancreatic tumors, trauma, and pancreatitis.     

Epidermoid Cyst of the Spleen

Background

The aim of this study is to elucidate the characteristics, clinical presentations, and management of epidermoid cysts located in the spleen and the intrapancreatic accessory spleen.

Methods

Data pooled for analysis were collected from epidermoid cyst cases encountered in the study institution and sporadic case reports obtained from the English literature.

Results

There were 115 cases of epidermoid cyst. Seventy eight (67.8 %) were found in the spleen, whereas 37 (32.2 %) were found in the intrapancreatic accessory spleen. Comparing between the two groups, the splenic group showed female predominance, younger age, and larger cystic size. For symptoms, left upper abdominal mass (57.7 %) and left upper abdominal pain (39.0 %) were more commonly found in the spleen group. Meanwhile, the intrapancreatic accessory spleen group had higher percentage of asymptomatic cysts (59.5 %). As for surgical indication, majority of patients in the spleen group underwent surgery for symptomatic relief (75.4 %), while the intrapancreatic accessory spleen group underwent surgery mainly for suspicious malignancy (90.0 %).

Conclusions

Surgical treatment for epidermoid cysts of the spleen is considered the optimal treatment for either alleviating the symptoms caused by a bulky cyst or for determining the histopathologic nature of a suspicious malignant cystic neoplasm.     

Hand-assisted laparoscopic distal pancreatectomy with minilaparotomy for distal pancreatic cystadenoma

Two patients with cystic tumors of the pancreas treated by laparoscopic distal pancreatectomy are presented. The first patient was a 34-year-old woman with a 6-cm cystadenoma of the tail of the pancreas treated with a complete laparoscopic distal pancreatectomy. After mobilization of the distal pancreas and spleen, the pancreas was transected proximally together with the splenic artery and vein using an endoscopic linear stapler. The second patient was a 71-year-old woman with a 6-cm cystadenoma of the body of the pancreas, treated by hand-assisted laparoscopic distal pancreatectomy with minilaparotomy because the tumor was adjacent to the portal vein and celiac axis. Using an upper median minilaparotomy, dissection of the gastrocolic ligament, division of the splenic artery, and transection and closure of the pancreas were performed. Division of the splenic vein and mobilization of the distal pancreas and spleen were performed via a hand-assisted laparoscopic approach. There were no postoperative complications (such as pancreatic fistulas) in either patient, and the postoperative courses were uneventful. The patients returned to normal activity within 1 week after the operation. Complete laparoscopic and hand-assisted laparoscopic distal pancreatectomy are preferable to conventional open surgery for benign tumors of the pancreas because of their less-invasive nature. Additionally, in tumors of the body of the pancreas, hand-assisted laparoscopic distal pancreatectomy might have the advantages of laparotomy and laparoscopy in terms of handling the splenic artery and vein just below the minilaparotomy site, suggesting an easier and safer procedure than complete laparoscopic distal pancreatectomy. Therefore, hand-assisted laparoscopic distal pancreatectomy can be recommended as a useful alternative to complete laparoscopic distal pancreatectomy for selected patients with benign tumors of the body and tail of the pancreas.     

Invasive carcinoma of the pancreas derived from intraductal papillary adenocarcinoma without mucin hypersecretion but with changes in the pancreatic duct on pancreatography

We present a case of invasive carcinoma of the pancreas derived from intraductal papillary adenocarcinoma without mucin hypersecretion in a 65-year-old man with a 45-year history of alcohol abuse and a 2-year follow-up of chronic pancreatitis. Two years previously, in May 1998, he was admitted for investigation of abdominal pain. Computed tomography (CT) showed diffuse dilation of the main pancreatic duct with atrophy of the pancreatic parenchyma. Endoscopic retrograde pancreatography (ERP) showed a diffusely dilated main pancreatic duct with irregular side branches in the head of the pancreas. Chronic alcoholic pancreatitis was diagnosed on the basis of the pancreatography findings. The patient was readmitted for investigation of progressive weight loss in August 2000. Serum CA19-9 levels were markedly elevated (750 U/ml) and CT showed enlargement of the head and body of the pancreas. ERP showed irregularity of the main pancreatic duct in the head of the pancreas, and the distal main pancreatic duct (which was dilated on initial ERP examination) was interrupted in the body of the pancreas. Suspected pancreatic carcinoma was diagnosed, and pylorus-preserving pancreatoduodenectomy was performed. Frozen section examination of the cut end of the pancreas revealed ductal carcinoma, and total pancreatoduodenectomy with portal vein resection was performed. Histologically, the resected tumor was diagnosed as an invasive carcinoma derived from intraductal papillary adenocarcinoma without mucin hypersecretion. We recommend observing changes in the pancreatic duct on pancreatography to diagnose invasive carcinoma of the pancreas derived from intraductal papillary adenocarcinoma in a resectable state. Received: February 6, 2002 / Accepted: June 10, 2002 Offprint requests to: S. Ariizumi