Sonazoid-enhanced ultrasonography for the diagnosis of an intrapancreatic accessory spleen: a case report

The imaging features of ectopic spleen: which modality is more consistent? A cases series report and literature reviews

Ectopic spleen (ES) is a rare condition. It is difficult to diagnose with conventional imaging modalities. In this case series, we presented the imaging features of three misdiagnosed ES cases in our hospital and previously reported cases to compare the consistency of enhancement patterns among different imaging modalities with varied phases. Finally, 22 cases were reviewed. We determined that variable arterial phase enhancement and persistent enhancement throughout the portal and delayed phases are present in contrast-enhanced ultrasound (CEUS) imaging of the ES and found the arterial phase of CEUS had the highest consistency compared with computerized tomography (CT) and magnetic resonance imaging (MRI).

A review of contrast-enhanced ultrasound using SonoVue® and Sonazoid™ in non-hepatic organs

Contrast-enhanced ultrasound (CEUS) is a dependable modality for the diagnosis of various clinical conditions. A judicious selection of ultrasound contrast agent (UCA) is imperative for optimizing imaging and improving diagnosis. Approved UCAs for imaging the majority of organs include SonoVue, a pure blood agent, and Sonazoid, which exhibits an additional Kupffer phase. Despite the fact that the two UCAs are increasingly being employed, there is a lack of comparative reviews between the two agents in different organs diseases. This review represents the first attempt to compare the two UCAs in non-hepatic organs, primarily including breast, thyroid, pancreas, and spleen diseases. Through comparative analysis, this review provides a comprehensive and objective evaluation of the performance characteristics of SonoVue and Sonazoid, with the aim of offering valuable guidance for the clinical application of CEUS. Overall, further clinical evidences are required to compare and contrast the dissimilarities between the two UCAs in non-hepatic organs, enabling clinicians to make an appropriate selection based on actual clinical applications.

Comments on and Illustrations of the EFSUMB CEUS Guidelines: Transabdominal and Endoscopic Ultrasound Features of Intrapancreatic Metastases and the Role of Multiparametric Imaging and EUS-Guided Sampling in Rare Pancreatic Tumors

A definite pathologic diagnosis of intrapancreatic metastasis is crucial for the management decision, i.e., curative or palliative surgery versus chemotherapy or conservative/palliative therapy. This review focuses on the appearance of intrapancreatic metastases on native and contrast-enhanced transabdominal ultrasound and endoscopic ultrasound. Differences and similarities in relation to the primary tumor, and the differential diagnosis from pancreatic carcinoma and neuroendocrine neoplasms are described. The frequency of intrapancreatic metastases in autopsy studies and surgical resection studies will be discussed. Further emphasis is placed on endoscopic ultrasound-guided sampling to confirm the diagnosis.

The management of pancreatic metastasis from synovial sarcoma of the soft tissue: A case report

Pancreatic metastases are rare, accounting for 2%–3% of pancreatic tumors. The pancreas represents an unusual metastatic site of synovial sarcoma (SS) outside the usual localizations (regional nodes, lung, bone, and liver). The diagnosis is evoked by the personnel medical history of SS and imaging then confirmed by histological examination of the guided pancreatic biopsy. Its therapeutic management is mainly surgical with extensive removal of the lesion. So far only four cases have been reported in the English literature. We reported the case of a male aged 30-year-old who was admitted to our Institute for a local recurrence of SS of the left thigh which was initially treated by surgical excision. The patient underwent a wide surgical excision followed by chemotherapy and radiotherapy. About 15 months later, he experienced a pancreatic metastasis of his SS. He had a caudal splenopancreatectomy with partial resection of the transverse colon followed by chemotherapy. This report highlights the diagnostic difficulties of this rare localization and therapeutic challenge.

The real cause of right lower abdominal pain: an analysis of ultrasonographic findings

A pelvic accessory spleen is uncommon and most patients with this condition are asymptomatic. Ureteral calculus is a common disease and can cause acute abdominal pain. We report a 51-year-old male patient who presented at our hospital with acute right lower abdominal pain and gross hematuria. A large mass on the right side of the pelvis was detected on an ultrasound examination, as well as a calculus in the lower segment of the right ureter. Computed tomography angiography showed the presence of a long vascular pedicle with an artery originating from the splenic artery and a vein that joined with the splenic vein. Laparoscopy was carried out and it showed a solid mass covered with omentum on the right lower abdomen. The mass was then removed surgically. Histopathological examination of the resected specimens confirmed splenic tissue. We speculate that the accessory spleen and ureteral calculus caused right lower abdominal pain in our case. However, the ureteral calculus might have played a much more important role in causing acute right lower abdominal pain than the accessory spleen.

Pancreatic nodule positive for 68-Ga-DOTAPEPTIDE-PET: NET or ectopic spleen? The importance of a good differential diagnosis

Background

Accessory spleen is a congenital defect in which splenic tissue is present outside the spleen. In 20% of cases, accessory spleen is localized within the pancreatic tail, a condition known as IPAS. The identification of this benign anomaly, which affects about 2% of general population, is not easy because it is often mistaken for a pNET which is more common, at around 5%. A 68-Ga-DOTAPEPTIDE-PET normally identifies pNETs with high rate of sensitivity and specificity, but in some conditions, it produces false positives, including IPAS.

Materials and tools

A clinical case we recently encountered, prompted us to review the available medical literature on the topic. Typing “intrapancreatic accessory spleen” into PubMed database and limiting research to the last 10 years yielded 121 results from which we selected the most relevant articles for decision-making, with a brief explanation of the reasons for selecting those. Our analysis focused on the most critical and least descriptive articles, those which clearly indicated the importance of differential diagnosis by promoting the use of advanced investigations in case of pancreatic nodule suspected for IPAS. Ultimately, our objective was to update the available guidelines recommendations.

Discussion and conclusions

Despite concern in the medical literature, a differential IPAS diagnosis is still subordinate to other clinical, radiological, nuclear medicine, and cytological criteria. After reviewing the literature, we recommend that IPAS should always be considered as a possibility before diagnosis of pNET is made. IPAS should be suspected in the presence of the following findings: asymptomatic pancreatic nodule found incidentally, absence of laboratory findings of NETs, localization in the pancreatic tail, between 1 and 3 cm in size with well-defined margins, homogeneous enhancement, and similar attenuation to the spleen on CT and MRI. In these cases, the use of advanced investigations beyond 68-Ga-DOTAPEPTIDE-PET must be systematic. The recognition of IPAS is not only a diagnostic refinement, but it also avoids unnecessary surgery for the patient. 

Superparamagnetic iron-oxide-enhanced diffusion-weighted magnetic resonance imaging for the diagnosis of intrapancreatic accessory spleen

PURPOSE

To evaluate the diagnostic performance of superparamagnetic iron-oxide (SPIO)-enhanced diffusion-weighted image (DWI) for distinguishing an intrapancreatic accessory spleen from pancreatic tumors.

MATERIALS AND METHODS

Twenty-six cases of intrapancreatic accessory spleen and nine cases of pancreatic tail tumors [neuroendocrine tumor (n = 8) and pancreatic adenocarcinoma (n = 1)] were analyzed. Two blind reviewers retrospectively reviewed the SPIO-enhanced magnetic resonance imaging (MRI) scans. The lesion visibility grades were compared and the diagnostic performance of SPIO-enhanced DWI was compared to those of SPIO-enhanced T2WI and T2*WI with the use of a receiver operating characteristic (ROC) analysis.

RESULTS

The grade of lesion visibility was the highest on DWI [mean ± standard deviation (SD): 2.8 ± 0.3] followed by T2WI (2.3 ± 0.7, p < 0.001) and T2*WI (2.1 ± 0.7, p < 0.0001). Reviewers 1 and 2 correctly characterized the presence or absence of SPIO uptake in 34 of 35 cases (97.1%) on DWI, 24 (68.6%) and 25 (71.4%) cases on T2WI, respectively, and 16 (45.7%) and 17 (48.6%) cases on T2*WI. The area under the ROC curve (AUC) of DWI was 0.974 and 0.989 for reviewers 1 and 2, respectively. For Reviewer 1, the AUC of DWI was significantly higher than that of T2*WI (0.756, p < 0.01), although it was not significantly different from that of T2WI (0.868, p = 0.0857). For Reviewer 2, the AUC of DWI was significantly higher than those of T2WI (0.846, p < 0.05) and T2*WI (0.803, p < 0.01).

CONCLUSION

The diagnostic performance of SPIO-enhanced DWI was better than those of SPIO-enhanced T2*WI and T2WI for the diagnosis of intrapancreatic accessory spleen.

Intrapancreatic accessory spleen false positive to 68Ga-Dotatoc: case report and literature review

Background

Intrapancreatic accessory spleen (IPAS) is an uncommon finding of pancreatic mass. Differential diagnosis with pancreatic tumor, especially with non-functional neuroendocrine tumor (NF-NET), may be very hard and sometimes it entails unnecessary surgery. A combination of CT scan, MRI, and nuclear medicine can confirm the diagnosis of IPAS. 68-Ga-Dotatoc PET/CT is the gold standard in NET diagnosis and it can allow to distinguish between IPAS and NET.

Case presentation

A 69-year-old man was admitted to our hospital for an incidental nodule in the tail of the pancreas with focal uptake of 68-Ga-dotatate at PET/CT. NET was suspected and open distal splenopancreatectomy was performed. Pathologic examination revealed an IPAS.

Conclusion

This is the second IPAS case in which a positive 68Ga-Dotatoc uptake led to a false diagnosis of pancreatic NET. Here is a proposal of a literature review.

Epidermoid cyst in intrapancreatic accessory spleen: A systematic review

BACKGROUND/OBJECTIVES

Due to its rarity, epidermoid cyst in intrapancreatic accessory spleen (ECIPAS) is still a diagnostic dilemma during clinical practice. The aim of this review was to summarize the epidemiologic features and management of ECIPAS.

METHODS

MEDLINE and EMBASE were searched for English articles reporting on ECIPAS up to April 30th, 2018 following the methodology suggested by the PRISMA guidelines. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).

RESULTS

A total of 56 patients from 47 full articles were included for the final data synthesis. More than half of the ECIPASs (59%) were found incidentally. The female/male ratio was 1.33. ECIPAS is typically a single mono-/multi-lobular cystic lesions in the pancreatic tail with thickened cystic wall or various amount of solid component which had identical density/signal to the spleen on imaging examinations. The cyst is filled with serous or non-serous fluid. Recognition of the surrounding ectopic splenic tissue is the key point to diagnose ECIPAS. However, no preoperative examination was able to make a definite diagnosis. Almost all the patients (96%) received surgical treatment, due to the suspicion of pancreatic malignant or potentially malignant cystic tumor, especially mucinous cystic neoplasm (MCN).

CONCLUSIONS

Although seldom encountered, ECIPAS should be considered as a differential diagnosis for pancreatic cystic lesions, especially when solid component was detected. As a benign disease, unnecessary surgery should be avoided. Because it is difficult to make a definite diagnosis preoperatively by one single examination, multiple modalities may be required.

Intrapancreatic accessory spleen: a diagnostic dilemma

BACKGROUND

As intrapancreatic accessory spleen (IPAS) is rarely encountered during clinical practice, the aim of this review was to summarize the epidemiologic features, the diagnosis and treatment of IPAS.

METHODS

MEDLINE and EMBASE were searched for articles reporting on IPAS. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).

RESULTS

A total of 105 patients were included, of which 73% were detected incidentally. The male/female ratio was 1.23. The size of IPAS in patients who had previously undergone splenectomy was larger than that of patients without prior splenectomy (2.5 cm vs 1.5 cm; p = 0.020). No preoperative examination was able to make a definite diagnosis for all IPASs. More than half of the patients (55%) received surgical treatment, most of which (87%) were suspected as pancreatic neuroendocrine tumors (p-net) preoperatively.

CONCLUSIONS

Although rare, IPAS should be considered in the differential of patients with suspected incidental p-net, especially if there has been a past history of splenectomy. Preoperative diagnosis is important as unnecessary surgery can be avoided. As it is difficult to make a definite diagnosis of IPAS by one single examination, multiple techniques may be required.

An intrapancreatic accessory spleen presenting as a rapidly growing pancreatic mass after splenectomy in a patient with hereditary spherocytosis: a case report and literature review

The case of a 16-year-old boy with an intrapancreatic accessory spleen presenting as a rapidly growing pancreatic mass after splenectomy for splenomegaly due to hereditary spherocytosis is reported herein. When he was 15 years old, the patient visited at a hospital due to jaundice and radiological examinations showed a huge spleen with a 2-cm mass near or in the pancreatic tail. Sonazoid-enhanced ultrasonography showed hypervascularity in the mass located near the pancreatic tail, which was suspicious for an accessory spleen. During splenectomy by laparotomy, the mass could not be found by inspection or intraoperative ultrasonography. One year after the splenectomy, the mass grew rapidly to 4 cm. Laparoscopic surgery was performed to aid in the differential diagnosis of the mass, and a laparoscopic ultrasonogram revealed that the mass was located in the pancreatic tail. The patient underwent laparoscopic distal pancreatectomy and was discharged uneventfully on the 11th postoperative day.

Symptomatic pelvic accessory spleen in a female adolescent: Case report

Accessory spleens are congenital foci of healthy splenic tissue that are separate from the main body of the spleen. They occur in 10-30% of individuals; a wandering accessory spleen located in the pelvis is uncommon. Most patients are asymptomatic. We describe the case of a female adolescent presenting with acute abdominal pain who had a pelvic accessory spleen that mimicked an adnexal mass. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:600-602, 2017.

Comparison of Contrast-Enhanced Ultrasound and Gadolinium-Ethoxybenzyl-Diethylenetriamine Pentaacetic Acid-Enhanced MRI for the Diagnosis of Macroscopic Type of Hepatocellular Carcinoma

OBJECTIVE

We compared the efficacy of contrast-enhanced ultrasound sonography (CEUS) with sonazoid and gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI for the assessment of macroscopic classification of nodular hepatocellular carcinoma (HCC).

METHODS

Seventy-seven consecutive patients with 79 surgically resected HCCs who underwent both preoperative CEUS and Gd-EOB-DTPA-enhanced MRI were enrolled in this retrospective study. Based on the macroscopic diagnosis of resected specimens, nodules were categorized into the simple nodular (SN) and non-SN type HCC. Two hepatologists independently assessed image datasets of the post-vascular phase of CEUS and hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI to compare their diagnostic performance.

RESULTS

Gd-EOB-DTPA-enhanced MRI enabled the evaluation of macroscopic classification in a significantly larger number of nodules than CEUS (78/79 (98.7%) vs. 70/79 (88.6%), p < 0.05). Of 70 nodules that could be evaluated by both modalities, 41 and 29 nodules were pathologically categorized as SN and non-SN, respectively. The areas under the receiver operating characteristic curve (AUC) for non-SN did not differ between CEUS and Gd-EOB-DTPA-enhanced MRI (reader 1: 0.748 for CEUS, 0.808 for MRI; reader 2: 0.759 for CEUS, 0.787 for MRI). The AUC of combined CEUS and Gd-EOB-DTPA-enhanced MRI for SN HCC was 0.855 (reader 1) and 0.824 (reader 2), indicating higher AUC values for the combined modalities.

CONCLUSIONS

The diagnostic performance for macroscopic classification of nodular HCC of CEUS was comparable with that of Gd-EOB-DTPA-enhanced MRI, although some HCCs could not be evaluated by CEUS owing to lower detectability. The combination of the 2 modalities had a more accurate diagnostic performance.

A case report of pancreatic metastasis from synovial sarcoma successfully treated by metastasectomy with adjuvant chemotherapy

INTRODUCTION

Synovial sarcoma is a malignant soft tissue sarcoma which arises near joints. The most frequent metastasis sites of synovial sarcoma are the lungs, lymph nodes, and bone. Pancreatic metastasis is quite rare; only 3 cases have been reported worldwide to date. We herein present the 4th case of pancreatic metastasis from synovial sarcoma.

METHODS AND RESULTS

A 32-year-old man underwent extended excision of synovial sarcoma in the left pelvis and femur in 2009. In 2013, follow-up contrast-enhanced computed tomography revealed a 35-mm heterogeneously enhanced mass in the pancreas body. Endoscopic ultrasound-guided fine needle aspiration of the mass revealed a diffuse proliferation of atypical spindle cells in a fascicular arrangement. Because the histology was quite similar to the resected specimen of synovial sarcoma in 2009, the mass was suspected to be a metastasis from synovial sarcoma. Laparoscopic distal pancreatectomy with adjuvant adriamycin/ifosfamide chemotherapy was subsequently performed. Synovial sarcoma-specific SS18-SSX1 (synovial sarcoma translocation, chromosome 18-synovial sarcoma X1) or SS18-SSX2 chimera mRNA was detected in the resected specimen, confirming the diagnosis of metastasis from synovial sarcoma. The patient did well for 30 months without recurrence.

CONCLUSION

This case suggests that pancreatic metastasis from synovial sarcoma can be successfully treated by metastasectomy with adjuvant chemotherapy.

[A case of splenic hamartoma diagnosed by contrast-enhanced ultrasonography and magnetic resonance imaging]

Splenic hamartoma is a very rare benign tumor, which is usually found incidentally after splenectomy or autopsy. Although percutaneous needle biopsy can be performed, it carries a high risk of bleeding after the procedure. Therefore, diagnosis is usually made by surgical resection. Herein, we report a case of splenic hamartoma diagnosed by magnetic resonance imaging and contrast-enhanced ultrasonography, which enables visualization of the unique signals of microbubbles in the vessels in real time. Relevant literature is also reviewed.

Images of Sonazoid-enhanced ultrasonography in multistep hepatocarcinogenesis: comparison with Gd-EOB-DTPA-enhanced MRI

BACKGROUND

Little is known about the difference in enhancement patterns of hepatocellular carcinoma (HCC) during multistep hepatocarcinogenesis between the post-vascular phase of Sonazoid-enhanced ultrasonography (SEUS) and hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine (Gd-EOB-DTPA)-enhanced MRI, as well as uptakes of Sonazoid and Gd-EOB-DTPA by HCC.

METHODS

Seventy patients with 73 histologically proven HCCs (33 hypovascular well-differentiated HCCs and 40 progressed HCCs) and 9 dysplastic nodules (DNs) were enrolled. Enhancement patterns of the lesions on the post-vascular phase of SEUS and hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were evaluated. Uptakes of Sonazoid and Gd-EOB-DTPA were assessed by Sonazoid enhancement index and EOB enhancement ratio in relation to immunohistochemistry of CD68 and organic anion transporting polypeptide 8 (OATP8), respectively.

RESULTS

On the post-vascular phase of SEUS, none of the 9 DNs and 3 of 33 hypovascular well-differentiated HCCs (9 %) were hypoechoic, whereas 3 of 9 DNs (33 %) and 31 of 33 hypovascular well-differentiated HCCs (94 %) showed hypointensity on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI. Of 31 progressed HCCs, 95 and 93 % were hypoechoic and hypointense on the post-vascular phase of SEUS and hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI, respectively. Sonazoid enhancement indexes decreased in progressed HCCs, correlating with lower Kupffer cell numbers (P < 0.001). EOB enhancement ratios decreased in hypovascular well-differentiated and progressed HCCs, as OATP8 expression declined (P < 0.001).

CONCLUSIONS

In stepwise hepatocarcinogenesis, uptake of Sonazoid starts decreasing later than that of Gd-EOB-DTPA. Although signal reductions on the post-vascular phase of SEUS or hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI suggest HCC, hypoechoic appearance on the post-vascular phase of SEUS might be HCC-specific, particularly progressed HCC.

A case of sclerosing angiomatoid nodular transformation of the spleen: correlations between contrast-enhanced ultrasonography and histopathologic findings

Sclerosing angiomatoid nodular transformation (SANT) is a recently recognized benign vascular lesion of the spleen. Detection of SANT as an incidentaloma has increased due to improvements in imaging techniques. However, a definitive diagnosis of SANT on CT or MRI remains difficult. We report the use of contrast-enhanced ultrasonography with Sonazoid in a case of SANT in a 50-year-old woman, with gross and microscopic pathologic correlations.