Splenosis: a review

[18F]FDOPA PET/CT in Solid Pseudopapillary Tumor of the Pancreas: a Recurred Tumor Mimicking Splenosis

Solid pseudopapillary tumor (SPT) of the pancreas is a neoplasm with low malignant potential. It is often challenging to diagnose SPT due to its nonspecific clinical and radiological features, and [18F]FDOPA is effective in diagnosing SPT, particularly in differentiating SPT from benign conditions such as splenosis. A 55-year-old woman underwent distal pancreatectomy and splenectomy for histologically confirmed SPT. She was also initially diagnosed with splenosis. During follow-up, sizes of multiple nodular lesions were increased, raising the possibility of peritoneal seeding of SPT. For diagnosis, a spleen scan and SPECT/CT were performed using 99mTc-labeled damaged red blood cells, which showed no uptake in the peritoneal nodules. Subsequent [18F]FDOPA PET/CT revealed [18F]FDOPA-avidity of the nodules. The patient underwent tumor resection surgery, and the nodules were pathologically confirmed as SPT.

False positive metastatic disease due to combined thoracic and subcutaneous splenosis

A 56-year-old man presented with dyspnea secondary to pulmonary emboli and dilated cardiomyopathy. His past medical history included a history of emergency laparotomy, splenectomy, and splenic flexure resection following a gunshot injury 30 years ago. CT and MRI imaging demonstrated multiple homogeneously enhancing lobulated lesions at the left-sided pleura and chest wall with an irregular calcified spleen. The aforementioned lesions demonstrated a similar level of tracer uptake to the splenic activity with no evidence of other FDG avid malignancy on the follow-up 18F-FDG PET study. All the above-mentioned pleural and chest wall lesions demonstrated intense tracer accumulation on technetium-99m labeled heat-damaged red cell scintigraphy, consistent with combined thoracic and subcutaneous splenosis.

A pleural based mass in a post-partum woman

Can you diagnose this case of a 27-year-old female who presented 1-week post-partum with an incidental finding of intrathoracic masses and probable hilar lymphadenopathy? https://bit.ly/3S3ejVK.

Primary and secondary tumors of the peritoneum: key imaging features and differential diagnosis with surgical and pathological correlation

Peritoneal malignancies represent a diagnostic challenge for abdominal radiologists, oncologists, surgeons and pathologists in multidisciplinary teams, who must address their differential diagnosis, staging and treatment. In this article, we explain the pathophysiology of these processes and lay out the role of different imaging techniques in their evaluation. Then, we review the clinical and epidemiological aspects, the main radiological features and the therapeutic approaches for each primary and secondary peritoneal neoplasm, with surgical and pathological correlation. We further describe other rare peritoneal tumors of uncertain origin and a variety of entities that may mimic peritoneal malignancy. Finally, we summarize the key imaging findings of each peritoneal neoplasm to facilitate an accurate differential diagnosis that may impact patient management.Clinical relevance statementImaging plays an essential role in the evaluation of peritoneal malignancies, assessing their extension, detecting unfavorable sites of involvement and facilitating an accurate differential diagnosis, helping to choose the best therapeutic approach.

Spleen regeneration after subcutaneous heterotopic autotransplantation in a mouse model

BACKGROUND

Splenectomy may lead to severe postoperative complications, including sepsis and cancers. A possible solution to this problem is heterotopic autotransplantation of the spleen. Splenic autografts rapidly restore the regular splenic microanatomy in model animals. However, the functional competence of such regenerated autografts in terms of lympho- and hematopoietic capacity remains uncertain. Therefore, this study aimed to monitor the dynamics of B and T lymphocyte populations, the monocyte-macrophage system, and megakaryocytopoiesis in murine splenic autografts.

METHODS

The model of subcutaneous splenic engraftment was implemented in C57Bl male mice. Cell sources of functional recovery were studied using heterotopic transplantations from B10-GFP donors to C57Bl recipients. The cellular composition dynamics were studied by immunohistochemistry and flow cytometry. Expression of regulatory genes at mRNA and protein levels was assessed by real-time PCR and Western blot, respectively.

RESULTS

Characteristic splenic architecture is restored within 30 days post-transplantation, consistent with other studies. The monocyte-macrophage system, megakaryocytes, and B lymphocytes show the highest rates, whereas the functional recovery of T cells takes longer. Cross-strain splenic engraftments using B10-GFP donors indicate the recipient-derived cell sources of the recovery. Transplantations of scaffolds populated with splenic stromal cells or without them afforded no restoration of the characteristic splenic architecture.

CONCLUSIONS

Allogeneic subcutaneous transplantation of splenic fragments in a mouse model leads to their structural recovery within 30 days, with full reconstitution of the monocyte-macrophage, megakaryocyte and B lymphocyte populations. The circulating hematopoietic cells provide the likely source for the cell composition recovery.

The Role of the Spleen in Portal Hypertension

As liver disease progresses, intrahepatic vascular resistance increases (backward flow theory of portal hypertension) and collateral veins develop. Adequate portal hypertension is required to maintain portal flow into the liver through an increase in blood flow into the portal venous system (forward flow theory of portal hypertension). The splenic artery resistance index is significantly and selectively elevated in cirrhotic patients. In portal hypertension, a local hyperdynamic state occurs around the spleen. Splenomegaly is associated with a poor prognosis in cirrhosis and is caused by spleen congestion and by enlargement and hyperactivation of splenic lymphoid tissue. Hypersplenism can lead to thrombocytopenia caused by increased sequestering and breakdown of platelets in the spleen. The close relationship between the spleen and liver is reflected in the concept of the hepatosplenic axis. The spleen is a regulatory organ that maintains portal flow into the liver and is the key organ in the forward flow theory of portal hypertension. This review summarizes the literature on the role of the spleen in portal hypertension.

Unexpected post-operative haemorrhage: Could it be splenosis?

Ectopic splenic tissue can be classified as accessory spleen, polysplenia or a phenomenon termed as splenosis. Once believed a rare occurrence, the incidence of splenosis is now thought to be significantly higher. Generally, splenosis is asymptomatic and discovered incidentally during operation, imaging or at autopsy. The case presented herein describes an incidental finding of an intraabdominal splenosis, which was subsequently biopsied to investigate for peritoneal metastatic disease. The biopsied tissue subsequently caused significant post-operative haemorrhage. Past medical history and specific pre-operative imaging modalities for patients presenting with asymptomatic peritoneal or intra-abdominal nodules are discussed. Splenosis is highlighted as a common condition to consider prior to invasive investigations.

Abdominal splenosis mimicking peritoneal carcinomatosis of ovarian cancer

We present the clinical case of a 53-year-old woman referred for suspicion of recurrence of a mesonephric-like adenocarcinoma of the ovary. Abdominal and pelvic CT revealed multiple round/oval solid nodules with similar density scattered throughout the abdomen and pelvis, the biggest ones appearing in the left hypochondrium; no normal-appearing spleen or ascites were observed. These radiological findings and the absence of significant elevation of CA 125 levels made the radiologists hypothesize that these aspects were related to abdominal splenosis. They asked the patient about previous medical history of splenic injury, which she confirmed, referring it was a consequence of a remote major trauma. A ^99mTc-labeled heat-denatured erythrocytes (^99mTc-DRBC) scintigraphy/ hybrid SPECT/CT was then performed for definitive diagnosis; it showed spleen remnants as foci of increased radiopharmaceutical uptake in the same locations as the nodules appearing in the CT. This diagnostic work-up was consistent with abdominal splenosis, mimicking peritoneal carcinomatosis of ovarian cancer.

„Hyposplenie“, eine weitgehend unerkannte Immunschwäche: Ist die Sonografie hilfreich?

Das Immundefizienzsyndrom der funktionellen Hyposplenie/Asplenie ist weitgehend unerkannt. Die Goldstandardprozedur stellt die Technetium-99m-Szintigrafie von hitzedenaturierten Erythrozyten (TSZ) sowie der Nachweis von pitted Erythrozyten oder Howell-Jolly-Körperchen (HJB) dar. Erste Arbeiten weisen darauf hin, dass dieses Krankheitsbild mit einer kleinen Milz assoziiert ist. Ziel der vorliegenden Übersicht ist es, den Stellenwert der B-Bild-Sonografie und der kontrastunterstützten Sonografie bei der Immunschwäche der Hyposplenie darzustellen.

Incidental splenosis discovered during robotic assisted radical prostatectomy: A case report

Splenosis refers to the benign heterotopic auto transplantation of splenic tissue that most commonly arises following traumatic rupture of the spleen. It is most often associated with traumatic rupture of the spleen. While often asymptomatic, splenosis can mimic malignancy and may lead to unnecessary biopsy, chemotherapy, and surgery. This case report highlights an instance of splenosis discovered incidentally during robotic assisted radical prostatectomy. Splenules were sent for frozen section due to concern for malignancy. Retrospective analysis of imaging obtained prior to the procedure was consistent with splenosis.

Calcification in Thoracic Splenosis

Splenosis is a rare condition described as the implantation of ectopic splenic tissue, usually after a splenic rupture. Thoracic splenosis refers to acquired ectopic splenic tissue found within the thoracic cavity, often caused by thoracoabdominal trauma or surgery. Most cases are asymptomatic and many years may elapse before they are incidentally discovered on chest radiography or thoracic computed tomography. Splenosis is often misinterpreted as a malignancy on initial imaging. We wish to highlight a rare case of thoracic splenosis presenting with calcified and non-calcified nodules. Only two other cases of calcification have been reported in intrathoracic splenosis, neither of which provided CT images of this finding.

Transplantation of splenic tissue after splenectomy: A case report

Transplantation of splenic tissue is a rare condition that usually occurs after splenic trauma and splenectomy. It usually requires surgery for diagnosis and treatment. A 38-year-old Asian male with familial hemolytic disease underwent laparoscopic splenectomy for a traumatic rupture of the spleen one year prior. The patient developed middle-upper abdominal pain without any obvious cause, radiating to the back and chest seven months prior to presentation. The condition improved with conservative treatment but the patient experienced recurrent episodes. Abdominal CT suggested multiple gallstones in the gallbladder that changed after splenectomy and multiple nodules in the original splenic area; thus, transplantation of splenic tissue was considered. MRI suggested thick gall bladder bile, multiple stones and cholecystitis, and the spleen was not observed (the patient underwent laparoscopic splenectomy at our hospital one year previously due to traumatic splenic rupture); furthermore, there were multiple abnormal signal foci in the splenic area, so the possibility of spleen implantation was considered. Considering the patient's family history of a hereditary hemolytic disease, laparoscopic cholecystectomy was performed simultaneously with laparoscopic accessory splenectomy. The final pathological report revealed chronic cholecystitis, mixed calculi, red pulp dilation, hyperemia and bleeding in round tissue with blood clot formation and acute and chronic inflammatory cell infiltration. Clinicians must bear in mind the possibility of splenosis after splenic trauma and its image variations.

Spleen: Reparative Regeneration and Influence on Liver

This review considers experimental findings on splenic repair, obtained in two types of small animal (mouse, rat, and rabbit) models: splenic resections and autologous transplantations of splenic tissue. Resection experiments indicate that the spleen is able to regenerate, though not necessarily to the initial volume. The recovery lasts one month and preserves the architecture, albeit with an increase in the relative volume of lymphoid follicles. The renovated tissues, however, exhibit skewed functional profiles; notably, the decreased production of antibodies and the low cytotoxic activity of T cells, consistent with the decline of T-dependent zones and prolonged reduction in T cell numbers. Species-specific differences are evident as well, with the post-repair organ mass deficiency most pronounced in rabbit models. Autotransplantations of splenic material are of particular clinical interest, as the procedure can possibly mitigate the development of post-splenectomy syndrome. Under these conditions, regeneration lasts 1-2 months, depending on the species. The transplants effectively destroy senescent erythrocytes, assist in microbial clearance, and produce antibodies, thus averting sepsis and bacterial pneumonia. Meanwhile, cellular sources of splenic recovery in such models remain obscure, as well as the time required for T and B cell number reconstitution.

Subcutaneous Splenosis Presenting 37 years post-traumatic splenectomy; A Case Report

INTRODUCTION

The term splenosis refers to autotransplantation of splenic tissue in ectopic sites. Ectopic splenic tissue may be found in the liver, thorax, pelvis and subcutaneous tissues following traumatic splenectomy. Although clinically insignificant, local symptoms such as abdominal pain may arise. In this paper we report a case of subcutaneous splenosis presenting 37 years post-traumatic splenectomy.

CASE PRESENTATION

A 40-year-old medically free lady presented to our institution with a surgical history of post-traumatic splenectomy at the age of three and two cesarean sections. She complained for nonpainful right upper quadrant soft mass that has been stable in size over the years. Her laboratory results, including peripheral blood smear, were all within normal limits and no asplenic changes were detected. SPECT scan confirmed extraperitoneal splenosis in right upper quadrant.

DISCUSSION

Splenosis is an acquired form of ectopic splenic tissue that is defined as an auto-transplantation of a viable splenic tissue. It commonly occurs after traumatic rupture of the spleen.5 Splenosis has been widely reported around the world with an incidence of 16-67% after traumatic splenic rupture or splenectomy. Subcutaneous splenosis is an extremely rare condition, mostly observed in abdominal surgical scars. It is believed to follow laparotomy for splenectomy where splenic cells auto-implant or spread hematogenously at different locations.

CONCLUSION

Subcutaneous splenosis is a rare consequence of post-traumatic splenectomy that can manifest itself up to three decades after. Although concerning to the patient and alarming to the surgeon as it may resemble more serious entities such as abdominal wall sarcoma, surgical removal of asymptomatic splenosis is subject to the location of mass and patients' wishes.

Rare case of intrahepatic splenosis masquerading as malignancy

A 54-year-old man presented with abdominal pain and a history of post-traumatic splenectomy 33 years prior, imaging revealed an incidental hepatic mass.

Abdominal and pelvic splenosis: atypical findings, pitfalls, and mimics

Splenosis is an acquired form of ectopic splenic tissue that typically arises after trauma or splenectomy. It is often an incidental image finding in an otherwise asymptomatic patient, but the spectrum of symptoms varies based on the site of implantation. Radiologists should be familiar with the imaging features of splenosis to avoid mistaking it for malignancy. Splenosis has identical imaging features to that of the native spleen on US, CT, MRI, and nuclear medicine examinations. Therefore, when the radiologic findings support the diagnosis of splenosis, the patient can be spared invasive procedures for tissue sampling.

Extensive intrathoracic and intraperitoneal splenosis mimicking mesothelioma: a case report

Background

Splenosis is the heterotopic autotransplantation of splenic tissue after severe splenic trauma and/or splenectomy. The epidemiology is elusive, but splenosis is frequently misdiagnosed as malignant tumors of gastrointestinal, gynecological, or hematological origin before the correct diagnosis is ultimately found. We herein report a rare case of combined, extensive intraabdominal and intrathoracic splenosis initially presenting as pleural mesothelioma.

Case presentation

A 63-year-old Caucasian male presented with dyspnea and recurring thoracic pain. Initial X-ray and computed tomography scans showed disseminated intrathoracic and intraabdominal lesions. Consequently, thoracoabdominal mesothelioma or a polytopically metastasized cancer of unknown origin was suspected. A thorough examination of the patient’s medical history and contrast-enhanced ultrasound by a skilled examiner revealed the diagnosis of extensive abdominal and thoracic splenosis as a consequence of an abdominal gunshot wound with a ruptured diaphragm several decades earlier. Timely diagnosis by noninvasive measures prevented the patient from potential complications of harmful diagnostic procedures, including nuclear imaging and biopsies. The patient is currently treated for hepatitis C and chronic obstructive lung disease, whereas no specific treatment for splenosis is required.

Conclusions

We present a case of rare intrathoracic and intraperitoneal splenosis mimicking mesothelioma. Contrast-enhanced ultrasound and thorough patient history were used for diagnosis and prevented this patient from having to undergo potentially harmful diagnostics. Splenosis can occur after splenic trauma and, consequently, needs to be considered as a rare differential diagnosis to malignant tumors of various origins when a matching patient history is obtained.

Infectious outcomes after splenectomy for trauma, splenectomy for disease and splenectomy with distal pancreatectomy

Introduction

The spleen provides a unique immune function in its production of opsins directed against encapsulated bacteria. Splenectomy, therefore, increases the risk of infections in patients as well as post-operative complications. This study aims to assess the risk of post-operative complications within 5 years of splenectomy by indication for splenectomy: trauma, disease, or in association with a distal pancreatectomy for pancreatic disease. The relationship between vaccination and infectious outcomes was also investigated.

Methods

This study is a review of splenectomy cases between June 2005 and June 2015 at a single institution. Infection, splenectomy indication, and vaccination history were identified from electronic medical records and lab test confirmations. Data was analyzed using Student’s t test for continuous variables, the Mann–Whitney U test for ordinal variables, and a Chi-square/Fisher exact test for categorical variables.

Results

A total of 106 splenectomy patients were included: 35 traumatic (74% male) and 71 non-traumatic causes (42% male) with no significant difference in age. There were no statistical differences in complications during splenectomy and vaccination administration between the splenectomy indication groups: trauma, disease, and with distal pancreatectomy. There was a statistically significant higher infection rate within 5 years post-splenectomy in the non-traumatic vs traumatic group (42% vs 14.0%, p = 0.0040) with majority gastrointestinal (7/38) and respiratory (5/38) and surgical wound infections (3/38) observed in non-traumatic versus traumatic, respectively.

Conclusion

Results from data analysis show a statistically significant difference in rates of infection within 5 years post-operatively between traumatic versus non-traumatic indications for splenectomies, with the non-traumatic group experiencing a higher rate of infectious outcomes. The non-traumatic group included patients with disease and distal pancreatectomy indications. This suggests that patients who have non-traumatic causes may be at a higher risk of developing infections following splenectomy procedure. Additionally, vaccinations did not appear to have a protective effect.

Intrapancreatic accessory spleen mimicking pancreatic insulinoma with intrapancreatic metastasis in a cat

An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses.

Splenosis mimicking gastric obstructive tumor: Diagnostic workup and surgical excision

Splenosis is a condition that occurs after splenic rupture. A 29-year-old male patient with a history of splenectomy was admitted due to multiple vomiting episodes. The diagnostic workup was unable to differentiate between gastric GIST and splenosis. Laparoscopic surgical resection was performed leading to the diagnosis of splenosis.

Case report: A follow up of a major pelvic splenosis

The authors present a case of a young female with extensive pelvic splenosis, which was complicated by torsion of one of the splenosis nodules operated by laparoscopy. She has been followed during several years. The diagnosis was made on the basis of the history, imaging (ultrasound, CT scan, MRI, and Technetium 99m-labeled embrittled red blood cell scans), and blood workup. The diagnosis of splenosis can be made via complications such as torsion, infarction, hemorrhage, or most often incidentally. The treatment without symptoms is abstention.

Intraperitoneal splenosis mimics peritoneal carcinomatosis of leiomyosarcoma and ovarian cancer

OBJECTIVE

Leiomyosarcoma and ovarian cancer are often diagnosed late due to the absence of initial symptoms. Patients seek help when abdominal distension occurs; this is associated with pelvic tumor and carcinomatosis. Initial imaging often reveals pelvic tumors with diffuse abdominal nodules; however, this imaging could be misleading, such as in the cases of splenosis.

CASE REPORT

A female presented with vaginal bleeding at our outpatient department. Serum CA125 level was elevated. Abdominal and pelvic CT showed multiple uterine masses and left adnexal cysts with peritoneal nodules. Leiomyosarcoma or ovarian cancer with carcinomatosis was suspected. Exploratory laparotomy was performed. Multiple purple spots spreading over peritoneal cavity were noted during the surgery. Pathological examination revealed adenomyosis with multiple uterine myomas and left ovarian endometrioma. Splenic tissues peritoneal implants were observed.

CONCLUSION

In patients with a history of spleen rupture or splenectomy, splenosis should be considered in the differential diagnosis, especially in young patients.

Perirectal intraperitoneal splenosis: A case report of MRI with laparoscopic correlation

Splenosis is a benign acquired condition, which appears after rupture of the spleen and heterotopic auto-transplantation. Mostly found as an incidental finding on cross-sectional imaging, definitive diagnosis is frequently made histologically after resection or tissue sampling. We report a case of a 36-year-old male patient who presented with increased susceptibility to infections, chronic fatigue, and a history of traumatic splenic rupture. Cross-sectional imaging showed perirectal formations within the mesorectal fascia, and extraperitoneal splenosis was suspected. Due to the radiologically unclear entity of the masses, diagnostic laparoscopy with tissue sampling was performed. Intraoperatively the masses turned out to be intraperitoneal. Histological workup showed splenic tissue, consistent with intraperitoneal splenosis after splenic rupture. In this article we want to discuss important imaging findings and their differentials, as well as clinical implications for this rare entity.

Genotoxicity of fluoride subacute exposure in rats and selenium intervention

The aims of this study were to: (i) examine the toxic effects of sodium fluoride (NaF) in blood, liver, spleen, and brain cells of Wistar rats after the subacute exposure; (ii) explore the potential protective properties of selenium (Se) against fluoride toxicity after the simultaneous administration. Twenty male Wistar rats, eight weeks old, weighing approximately 140-190 g, were divided into four experimental groups (n = 5) as follows: I control-tap water; II NaF 150 ppm; III NaF 150 ppm and Se 1.5 mg/L; IV Se 1.5 mg/L, and had available water with solutions ad libitum for 28 days. DNA damage detected by comet assay was confirmed in the liver, spleen, and brain cells, but not in blood. Selenium supplementation together with NaF decreased DNA damage in liver and spleen cells. According to the histological findings, no changes were observed in spleen and brain tissues after NaF administration. Unlike the observed Se protective effect on the DNA level, no significant reduction of liver tissue injury was observed after the NaF and Se treatment, resulting in mild inflammation. Data of this study suggest that DNA damage after NaF subacute exposure at moderately high concentration was reduced in liver and spleen cells due to Se supplementation, but a similar change was not seen in the brain.

Splenosis mimicking lymphadenopathy

Splenosis is an autotransplantation of splenic tissue following traumatic rupture of the spleen or splenectomy. Generally, splenosis is asymptomatic. Therefore, most cases are incidental findings made during surgery, autopsy or after imaging studies for other purposes. Splenosis is a benign phenomenon, but it often shows similarity to the metastatic process. We present a case of asymptomatic intraperitoneal splenosis occurring in a 57-year-old male, in whom computed tomography urography showed lymphadenopathy suggesting a neoplastic process. A reconnaissance laparotomy was performed, and specimens were taken and sent for histopathological examination. The microscopic image of all the collected lesions corresponded to the normal spleen tissue. Due to an increasing number of traffic accidents, it is worth taking abdominal splenosis into consideration in the differential diagnosis of tumor-like changes, especially in patients with a history of splenic trauma or spleen removal. As a result, unnecessary surgery can be avoided in many cases.

Gastric splenosis mimicking a gastrointestinal stromal tumor: A case report

BACKGROUND

Mass lesions located in the wall of the stomach (and also of the bowel) are referred to as “intramural.” The differential diagnosis of such lesions can be challenging in some cases. As such, it may occur that an inconclusive fine needle aspiration (FNA) result give way to an unexpected diagnosis upon final surgical pathology. Herein, we present a case of an intramural gastric nodule mimicking a gastric gastrointestinal stromal tumor (GIST).

CASE SUMMARY

A 47-year-old Caucasian woman, who had undergone splenectomy for trauma at the age of 16, underwent gastroscopy for long-lasting epigastric pain and dyspepsia. It revealed a 15 mm submucosal nodule bulging into the gastric lumen with smooth margins and normal overlying mucosa. A thoraco-abdominal computed tomography scan showed in the gastric fundus a rounded mass (30 mm in diameter) with an exophytic growth and intense enhancement after administration of intravenous contrast. Endoscopic ultrasound scan showed a hypoechoic nodule, and fine needle FNA was inconclusive. Gastric GIST was considered the most probable diagnosis, and surgical resection was proposed due to symptoms. A laparoscopic gastric wedge resection was performed. The postoperative course was uneventful, and the patient was discharged on the seventh postoperative day. The final pathology report described a rounded encapsulated accumulation of lymphoid tissue of about 4 cm in diameter consistent with spleen parenchyma implanted during the previous splenectomy.

CONCLUSION

Splenosis is a rare condition that should always be considered as a possible diagnosis in splenectomized patients who present with an intramural gastric nodule.

Intrahepatic splenosis: a world review

Splenosis is defined as the autotransplantation of viable splenic tissue throughout various anatomic compartments. Intrahepatic splenosis (IHS) is rare and diagnosis is often challenging. This study aims to provide a comprehensive review on IHS. A literature review was performed on PubMed database. Fifty-six articles with 59 reported cases were included. The majority of the patients were male (n = 49, 83.1%). Median age was 51 years. Risk factors for hepatocellular carcinoma (HCC) included hepatitis B (n = 8, 13.6%) and cirrhosis (n = 12, 20.3%). The majority of the patients were asymptomatic (62.7%) and did not have risk factors for HCC (55.9%). We report a diagnostic triad for IHS: 1) previous history of abdominal trauma or splenectomy, 2) absence of risk factors for liver malignancy and 3) typical imaging features. Non-invasive diagnostic tests such as technetium-99m-tagged heat-damaged red blood cell scintigraphy are useful in diagnosis. Malignancy should be ruled out in the presence of risk factors for HCC.

Congenital intrathoracic accessory spleen is a very rare trick of nature: a case report

BACKGROUND

Congenital intrathoracic accessory spleen (CIAS) refers to a developmental anomaly resulting in the presence of splenic tissue within the chest. The differential diagnoses for the resulting mass are pulmonary malformations, or lesions with malignant potential. To our knowledge, only four cases of presumed CIAS have been described in literature to date, and no cases were reported in the United States.

CASE PRESENTATION

We report on a 14-year-old Caucasian female with a left chest mass discovered incidentally on a CT scan performed following an all-terrain vehicle accident. Following resection, the mass was diagnosed as a CIAS.

CONCLUSIONS

From our review of literature, we found that CIAS can pose a diagnostic dilemma as it is rare, difficult to distinguish from pulmonary sequestration, or malignancy, and biopsy is often inconclusive. Resection is required to rule out malignancy and determine the diagnosis. Pediatric thoracic surgeons should consider CIAS in their differential for an intrathoracic mass with an inconclusive biopsy.

Hox-Positive Adult Mesenchymal Stromal Cells: Beyond Positional Identity

Homeotic genes (Hox) are universal regulators of the body patterning process in embryogenesis of metazoans. The Hox gene expression pattern (Hox code) retains in adult tissues and serves as a cellular positional identity marker. Despite previously existing notions that the Hox code is inherent in all stroma mesenchymal cells as a whole, recent studies have shown that the Hox code may be an attribute of a distinct subpopulation of adult resident mesenchymal stromal cells (MSC). Recent evidence allows suggesting a "non-canonical" role for Hox gene expression which is associated with renewal and regeneration in postnatal organs after damage. In tissues with high regenerative capacity, it has been shown that a special cell population is critical for these processes, a distinctive feature of which is the persistent expression of tissue-specific Hox genes. We believe that in the postnatal period Hox-positive subpopulation of resident MSC may serve as a unique regenerative reserve. These cells coordinate creation and maintenance of the correct structure of the stroma through a tissue-specific combination of mechanisms. In this article, we summarize data on the role of resident MSC with a tissue-specific pattern of Hox gene expression as regulators of correct tissue reconstruction after injury.

Follicular lymphoma in a patient with splenosis: a case report

Splenosis refers to the seeding of splenic cells associated with surgery or trauma. Splenosis mimicking other diseases has been reported in the literature. To the best of our knowledge, this is the first case of follicular lymphoma in a patient with splenosis whose diagnosis of lymphoma was delayed because of a known history of splenosis. We report a 48-year-old male patient who underwent splenectomy because of injury from a high fall 20 years previously. He had no symptoms other than mild abdominal pain until 2 years previously, which was thought to be associated with splenosis. When his symptoms began to increase, he had explorative laparotomy for diagnosis, which was later confirmed as follicular lymphoma. Splenosis may delay the diagnosis of other conditions that can be underestimated. Clinicians should be aware of unusual symptoms in patients with splenosis.

Pelvic splenosis-A rare cause of pelvic mass

Splenosis is a medical condition that seldom occurs after splenic tissue spillage via trauma or surgery. Ectopic spleen tissues can be found almost anywhere within the body. Albeit benign, it is often misdiagnosed as a tumor. Surgery is not indicated unless symptomatic. The imaging of choice for pelvic splenosis, although conventional, is a sulfur colloid nuclear scintigraphy.

An extremely rare case of an oversized accessory spleen: case report and review of the literature

Background

The accessory spleen is a congenital defect characterized by a separated ectopic splenic parenchyma. The size is rarely more than 4 cm. The preoperative diagnosis is prohibitive preoperatively. The aims of the present manuscript were to present the case of a patient with a rare oversize accessory spleen and a review of the literature.

Case presentation

A 15-year-old boy was admitted to the emergency department following blunt abdominal trauma.

The computed tomographic scan showed a traumatic rupture of the spleen and a 7-cm mass at the left side of the retroperitoneal space. Conservative treatment started and aborted after 4 h due to the onset of haemodynamic instability. Splenectomy was performed. An accessory spleen was discovered. A second large mass in the retroperitoneum was diagnosed as a second large accessory spleen that was also left in place. The postoperative course was uneventful, and the patient was discharged on the 7th postoperative day. Seven months later, the CT scan showed viability of both accessory spleens.

Conclusion

An accessory spleen can be variously located and the retroperitoneal position is extremely uncommon. Preoperative diagnosis is still difficult, especially in emergency and as in our case, the literature shows the difficulty of reaching a diagnosis before surgery. The main misdiagnosis is neoplastic disease and for this reason accessory spleen can be wrongly removed.

An undiagnosed pre or intra operative retroperitoneal mass, closely to the spleen, have to be managed carefully. The diagnosis of accessory spleen needs to be ever considered as if found, represents a great possibility to conduct a normal life after splenectomy (of main spleen) for trauma.

Simultaneous small bowel and colon obstruction due to splenosis. A case report and review of literature

•

Splenosis is an autotransplantation of splenic tissues throughout the body post splenic rupture or splenectomy.

•

Symptomatic when hematological diseases have recurred.

•

Abdominal splenosis may rarely be associated with abdominal pain and/or gastrointestinal symptoms.

•

Further evaluation and treatment is mandatory when bowel obstruction is present.

•

Treatment consists of resection of problematic splenic nodules.

Introduction

Splenosis, an autotransplantation of splenic tissues in another compartment of the body, is only symptomatic when hematologic diseases have recurred or compression of other adjacent structures have occurred. Therefore, we report a clinical case of a patient with bowel obstruction due to splenosis.

Case presentation

A patient with a history of splenectomy, presented to the emergency room for abdominal pain and obstipation, suggesting intestinal obstruction which is also seen on CT scan. During laparotomy, multiple splenic nodules were seen on the mesentery of the small bowel and colon, with vascular bridges between them, resulting in bowel obstruction. Resection of splenic nodules was performed. The post-operative course was uneventful and the patient was discharged a week after.

Discussion

Although very rare, gastrointestinal symptoms may sometimes be described in patients with splenosis. Bleeding or obstruction can occur because of intramural grow or external compression, respectively. Treatment consists of resection of these nodules.

Conclusion

Splenosis should always be thought in patients with previous splenic rupture and presenting with incidental nodules seen on imaging, with further investigations when symptoms are present.

Splenosis of the Liver Capsule

Splenosis, a form of ectopic splenic tissue, is generally caused by heterotopic autotransplantation of splenic tissues after traumatic splenic rupture or splenectomy. The implants are often localized intraperitoneally, mostly in the left upper quadrant and splenic region. Hepatic foci are seen only on rare occasions. The differential diagnosis of splenosis foci from malignant masses can be challenging by conventional imaging and lead to unnecessary invasive procedures. This manuscript presents radiological and scintigraphic images of splenosis foci located in the peritoneal cavity and liver capsule of a 46-year-old man who underwent splenectomy due to traumatic splenic rupture 30 years ago.

Management of intrahepatic splenosis:a case report and review of the literature

Background

Splenosis is the heterotopic autotransplantation and implantation of splenic tissue after splenic trauma or splenectomy. Considering that splenosis often occurs in the mesentery, omentum, and peritoneum, intrahepatic splenosis has seldom been reported. We report a rare case of isolated intrahepatic splenosis in a 54-year-old man who presented with a liver mass thought to be hepatocellular carcinoma.

Case presentation

A 54-year-old man was referred to our hospital for further evaluation of a liver lesion. The patient was asymptomatic and had a history of emergent splenectomy after a high-altitude falling accident. Abdominal contrast-enhanced computed tomography revealed a 4.5 × 3.3 cm lesion that was located in segment IV of the left liver lobe. The lesion had an inhomogeneous enhancement during the arterial phase and diminished enhancement during the portal and equilibrium phases. Similar radiological features were also observed on a contrast magnetic resonance imaging scan. Partial hepatectomy was performed with the suspicion of hepatocellular carcinoma. Pathological examination of the liver specimen revealed intrahepatic splenosis.

Conclusion

Splenosis should be considered in differential diagnosis of a liver mass discovered years after splenic trauma or surgery. A proposed scoring system may be helpful in evaluating the suspicious degree of intrahepatic mass to be splenosis. Invasive treatments are not recommended for asymptomatic patients, since the splenosis can provide beneficial immunologic function.

Multiple intra-hepatic and abdominal splenosis: an easy call if you know about it

Hepatic splenosis represents the heterotopic implantation of splenic tissue caused by the spillage of cells from the spleen usually after splenectomy or splenic trauma. This condition is usually an incidental finding during surgery and its real incidence is unknown. Splenic implants, which can be placed anywhere in the abdominal cavity, are usually multiple and may be confused with different benign and malignant conditions such as renal tumors, abdominal lymphomas, and endometriosis. We hereby report an unusual case of multiple abdominal splenosis, with a particular intra-hepatic location, that could be misinterpreted as an hepato-cellular carcinoma.

Intrahepatic splenosis mimicking hepatic neoplasia

INTRODUCTION

Splenosis is defined as the heterotopic autoimplantation of splenic tissue following trauma to or surgery on the spleen.

CLINICAL CASE

We present a case of an asymptomatic 73-year-old male in whom hypervascular lesions were detected during routine exams. The patient reported a history of carotid artery surgery and cholecystectomy; he had a laparotomy incision from childhood but was unaware of the reason for it. The patient exhibited slightly elevated carcinoembryonic antigen (CEA) levels. Histopathology revealed intrahepatic heterotopic splenic parenchyma, with no evidence of neoplasia in either of the two lesions, the diameters of which were 1.5 cm and 3.6 cm. Patient received outpatient follow-up care for 24 months and experienced no complications.

DISCUSSION

Our clinical, laboratory, and imaging exams failed to reveal the etiology of the lesion. Because the masses were hypervascular lesions, a percutaneous liver biopsy was not feasible.

CONCLUSION

Through this report, we emphasize the importance of considering intrahepatic splenosis as a remote possibility in patients with hepatic nodules who have a history of splenectomy.

Determinants of postnatal spleen tissue regeneration and organogenesis

The spleen is an organ that filters the blood and is responsible for generating blood-borne immune responses. It is also an organ with a remarkable capacity to regenerate. Techniques for splenic auto-transplantation have emerged to take advantage of this characteristic and rebuild spleen tissue in individuals undergoing splenectomy. While this procedure has been performed for decades, the underlying mechanisms controlling spleen regeneration have remained elusive. Insights into secondary lymphoid organogenesis and the roles of stromal organiser cells and lymphotoxin signalling in lymph node development have helped reveal similar requirements for spleen regeneration. These factors are now considered in the regulation of embryonic and postnatal spleen formation, and in the establishment of mature white pulp and marginal zone compartments which are essential for spleen-mediated immunity. A greater understanding of the cellular and molecular mechanisms which control spleen development will assist in the design of more precise and efficient tissue grafting methods for spleen regeneration on demand. Regeneration of organs which harbour functional white pulp tissue will also offer novel opportunities for effective immunotherapy against cancer as well as infectious diseases.

Usefulness of Splenic Scintigraphy in Differentiating Splenosis and Malignancy on Gallium 68 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-NaI3-octreotide

Somatostatin receptor (SSTR) imaging with gallium 68 (Ga-68) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptide positron emission tomography/computed tomography (PET/CT) has been introduced in clinical routine for the diagnosis and staging of neuroendocrine tumors (NETs) with high SSTR expression. Although it has high sensitivity for NETs, there are some known diagnostic pitfalls one should be aware of. We present a case of suspected NET where Ga-68 DOTA-NaI3-octreotide (NOC) PET/CT showed several abdominal lesions with high SSTR expression suggesting malignancy. On magnetic resonance imaging, the differential diagnosis of the lesions also included splenosis. Subsequent splenic scintigraphy with technetium-99m phytate showed uptake in all suspicious lesions, and biopsy confirmed the diagnosis of splenosis. Splenic scintigraphy with single-photon emission computed tomography/CT can be a helpful noninvasive diagnostic tool when splenosis is suspected on Ga-68 DOTA-peptide PET/CT.

Thoracic splenosis: History is the key

Splenosis is an acquired ectopic autotransplantation of splenic tissue; that occurs after traumatic splenic rupture and splenectomy [1]. Splenosis is a rare but benign disease, and the diagnosis can be challenging as the multiple incidentally found nodules could mimic malignancy [2]. Abdominopelvic Splenosis is thought to occur in as many as 65% of cases of splenic rupture [1]. However, Thoracic Splenosis is rare and usually involve the left parietal and visceral pleura [1,2]. Intraparenchymal lesions are less common but have been reported in cases of parenchymal and diaphragm laceration [1,2]. Taking a thorough history is of utmost importance, as these patients usually present more than two decades after the splenic traumatic rupture. The use of commonly available nuclear studies will further confirm the diagnosis [3]. This will help to avoid unnecessary procedures, like biopsies; and prevent the potential complications. We present a case of Thoracic Splenosis that highlights the importance of taking a detailed history; and the importance of using nuclear studies for the diagnosis. Further adding to its uniqueness, this case showed with multiple intraparenchymal nodules which is a less common presentation of Splenosis.

Thoracic splenosis mimicking a pleuropneumonia: A case report

RATIONALE

Splenosis is the development of one or more heterotopic splenic tissue autoimplants following rupture of the spleen and remains mostly asymptomatic.

PATIENT CONCERNS

We report a case of a 50-year old post-traumatic splenectomized man admitted for a left side community acquired pneumonia resistant to antibiotics.

DIAGNOSES

The diagnosis of intrathoracic ectopic spleen was suspected because of the history of spleen trauma with diaphragm rupture and the absence of Howell-Jolly bodies.

INTERVENTIONS

Technetium (Tc)-m colloid scintigraphy SPECT, fused with CT scan showed an intense radionuclide uptake on hyper vascularized masses without any additional pathologic uptake and confirmed the diagnosis of thoracic splenosis.

OUTCOMES

Despite any lifelong penicillin prophylaxis, he had no history of infections eight years after the diagnosis.

LESSONS

Physician must be aware of this differential diagnosis and of its consequences. Depending on its size and location, it may lead to incorrect diagnosis (tumor, empyema, abscess ...), treatment and invasive procedures while the diagnosis of splenosis only relies upon imaging studies associated with functionnal study of the uptake of particles or cells.

A unique case of bilateral ovarian splenosis and review of the literature

Splenosis is an acquired anomaly related to heterotopic auto-transplantation of splenic tissue following abdominal trauma or splenectomy. We report the first definitive bilateral ovarian case in a 65-year-old woman who underwent splenectomy following a motor vehicle accident 44 years prior to presentation. We review the literature and discuss the main differential diagnoses. Gross examination revealed a 1-cm well-circumscribed dark nodule on the surface of each ovary. Paraffin-embedded, formalin-fixed blocks were sectioned and stained with hematoxylin-eosin and immunostains (CK5/6, Calretinin, WT1, Vimentin). The histological presence of both red and white splenic pulp, delimitation from ovarian tissue and ovarian origin of blood supply, as well as medical history, led us to the correct diagnosis. The outer nodular surface was covered by mesothelium (WT1+, CK5/6+, Calretinin+, Vimentin+), which was in continuity with the ovarian surface epithelium. To our knowledge, only six previous cases of ovarian splenosis are reported. Our patient is the oldest, with a very long interval from splenectomy to presentation. Clinically, splenosis may mimic malignancy, and a correct diagnosis avoids unnecessary overtreatment. The differential diagnosis includes an accessory spleen, spleno-gonadal fusion, and splenic hamartoma: they should be excluded to come to the correct diagnosis.

[Pelvic nodules in a young woman: All is not endometriosis!]

Splenosis is a pathology resulting from a rupture of the spleen due to a trauma or a surgery. We report the case of a patient presenting with a splenosis, initially diagnosed as endometriosis-related pelvic nodules, the most frequent cause of pelvic nodules in women. We will describe the imaging strategy that led to the final diagnosis of splenosis.