Seeding of a Tumor in the Gastric Wall after Endoscopic Ultrasound-guided Fine-needle Aspiration of Solid Pseudopapillary Neoplasm of the Pancreas

Solid pseudopapillary neoplasm of the pancreas with hepatic metastases: problems and strategies

Background

Solid pseudopapillary neoplasms of the pancreas with hepatic metastases are infrequent and difficult to diagnose, and treatment is uncertain.

Methods

A retrospective analysis of clinical data from patients with pancreatic solid pseudopapillary neoplasm (SPN) hepatic metastases who underwent surgery at the First Hospital of Jilin University from January 2005 to December 2021 was conducted. A total of 287 patients with SPN were included in the study, of which 8 (3%) developed liver metastases, all of whom were treated surgically and recovered well after surgery. The clinical presentation, imaging features, surgical treatment, histopathological examination, and postoperative follow-up data (mean 70 months; range 28-138 months) of the patients were recorded and analyzed. Clinical response strategies can be derived by reviewing previous studies on hepatic metastases of SPNs.

Results

For resectable hepatic metastases from pancreatic solid pseudopapillary neoplasms, early surgery with total resection of the primary tumor and metastasis has shown great efficiency and is associated with patient good prognosis. In patients presenting unresectable hepatic metastases, aggressive tumor reduction surgery resulted in the alleviation of clinical symptoms and reduction of tumor burden while potentially achieving long-term survival.

Conclusion

For hepatic metastases of SPNs, a preoperative liver tissue biopsy is beneficial for a definitive diagnosis. Surgery demonstrates excellent therapeutic efficacy and is considered the preferred curative treatment approach. This paper presents clinical experiences with SPN-related hepatic metastases at the Affiliated Hospital of Jilin University, which can be used to guide patient counseling in clinical practice.

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine contrast-enhanced ultrasound guidelines. Rare pancreatic tumors, imaging features on transabdominal ultrasound and EUS with contrast enhancement: Rare epithelial pancreatic tumors: solid pseudopapillary neoplasm, acinar cell carcinoma, mixed neuroendocrine-non-neuroendocrine neoplasms, some rare subtypes of pancreatic adenocarcinoma and pancreatoblastoma

Rare malignant pancreatic lesions are systematically reported in this review. The focus is on the imaging appearance of the rare epithelial pancreatic tumors such as the solid pseudopapillary neoplasm, acinar cell carcinoma, rare subtypes of adenocarcinoma, and pancreatoblastoma as seen on ultrasound, EUS, and contrast-enhanced ultrasound or EUS. The present overview summarizes the data and shows that not every pancreatic tumor is likely to be the most common entities of ductal adenocarcinoma or neuroendocrine tumor.

Methods to increase the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions: An updated review

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a means to procure adequate specimens for histological and cytologic analysis. The ideal EUS-FNA should be safe, accurate, and have a high sample adequacy rate and low adverse events rate. In recent years, many guidelines and trials on EUS-FNA have been published. The purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding.

Multicenter Study on the Performance of Imaging Tests Compared to Endosonography-Guided Fine-Needle Aspiration in the Diagnosis of Solid Pseudopapillary Neoplasms of the Pancreas

Introduction

Imaging diagnosis of pancreatic solid-pseudopapillary neoplasms (SPNs) is difficult. Preoperative diagnosis by endosonography-guided fine-needle aspiration (EUS-FNA) is possible and has been reported in the literature in pancreatic tumors. However, its usefulness is still controversial. The aim of this study was to determine the accuracy of the EUS-FNA in the diagnosis of patients with SPN and describe the findings in computerized tomography (CT), magnetic resonance cholangiopancreatography imaging (MRI/MRCP), and EUS therefore comparing the imaging methods alone to the findings of microhistology (McH) obtained by EUS-FNA.

Materials and Methods

We retrospectively reviewed the medical records of patients undergoing EUS-FNA with suspected SPN in imaging studies in 5 Brazilian high-volume hospitals (two university hospitals and three private hospitals). The demographic data; findings in CT, MRI/MRCP, and EUS; and McH results obtained by EUS-FNA were noted prospectively. The final diagnosis was obtained after the anatomopathological examination of the surgical specimen in all patients (gold standard), and we compared the results of CT, MRI/MRCP, EUS, and the McH with the gold standard.

Results

Fifty-four patients were included in the study, of which 49 (90.7%) were women with an average age of 33.4 (range 11-78) years. The most common symptom presented was abdominal pain, present in 35.2% patients. SPN was detected incidentally in 32 (59%) patients. The average size of the tumors was 3.8 cm (SD: 2.26). The most common finding at EUS was a solid, solid/cystic, and cystic lesion in 52.9%, 41.1%, and 7.8% patients, respectively. The final diagnosis was 51 patients with SPN and 3 with nonfunctioning pancreatic neuroendocrine tumors (NF-NET). The correct diagnosis was made by CT, MRI/MRCP, EUS isolated, and EUS-FNA in 21.9%, 28.88%, 64.71%, and 88.24%, respectively. EUS-FNA associated with CT and MRI increased diagnostic performance from 22.72% to 94.11% and from 29.16% to 94.11%, respectively.

Conclusions

SPN are rare, incidentally identified in most cases, and affect young women. Differential diagnosis between SPN, NF-NET, and other types of tumors with imaging tests can be difficult. EUS-FNA increases preoperative diagnosis in case of diagnostic doubt and should be used whenever necessary to rule out NF-NET or other type of solid/cystic nodular lesion of the pancreas.

Improving diagnostic accuracy and appropriate indications for surgery in pancreatic cystic neoplasms: the role of EUS

BACKGROUND AND AIMS

Pancreatic cystic neoplasms (PCNs) represent a difficult preoperative diagnosis despite improvements in imaging. In this study, we compared preoperative and final pathologic diagnosis in a large cohort of resected PCNs, evaluating diagnostic accuracy with a specific focus on the value of EUS.

METHODS

A retrospective analysis of patients undergoing resection between 2009 and 2019 for presumed PCNs was performed. Preoperative workup was reviewed by analyzing the role of imaging and EUS. Patients with a benign histology who did not show absolute indication were categorized as "delayable surgery."

RESULTS

Of 585 patients who were retrospectively analyzed, in 108 (18.5%) final histology did not confirm preoperative diagnosis. EUS was associated with a lower rate of incorrect diagnosis (16%; P = .03), but the risk of overtreatment was similar regardless of instrumental diagnostic path (33/131 vs 68/328, P = .298). Dilatation of the main pancreatic duct and cytologic sampling were the only variables independently associated with a correct diagnosis (P < .001 and P = .041, respectively). Based on clinical presentation and final histology, pancreatic resection could have been spared or delayed in 101 of 459 patients (22%), and this was influenced by age (odds ratio [OR], .97; P = .002), cyst larger than 30 mm (OR, 1.89; P = .005), and type of operation (OR, 3.46 [P < .001] and 3.18 [P = .023] for distal pancreatectomies and other resections, respectively).

CONCLUSIONS

The overall risk of unnecessary immediate surgery for PCNs is about 22% in a high-volume referral center. EUS with cytologic sampling is a useful procedure in the diagnostic management of PCNs, improving their diagnostic accuracy.

Clinical dilemma of endoscopic ultrasound-guided fine needle aspiration for resectable pancreatic body and tail cancer

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a first-line procedure for definitive tissue diagnosis of pancreatic cancer because of its high accuracy and low complication rate. The overall sensitivity of EUS-FNA for the diagnosis of pancreatic cancer is approximately 90%; however, its diagnostic ability for small lesions (<10 mm) remains limited. Although EUS-FNA is a relatively safe procedure, with an overall morbidity of ≤2%, it should be noted that needle tract seeding (NTS) can occur after EUS-FNA, which may affect the patient prognosis negatively. In patients with resected pancreatic tumors, preoperative EUS-FNA is not associated with an increased risk of postoperative recurrence. However, NTS after EUS-FNA for resectable pancreatic body and tail cancer has been highlighted recently, particularly by Japanese endoscopists. Thus, the use of preoperative EUS-FNA for the diagnosis of resectable pancreatic body and tail cancer has become a clinical dilemma that challenges gastroenterologists and must be carefully considered on a case-by-case basis by weighing the benefits and risks. This review summarizes the pros and cons of performing EUS-FNA in patients with resectable pancreatic body and tail cancer and provides valuable insight for gastroenterologists treating pancreatic cancer.

Differentiation Between Solid Pseudopapillary Neoplasm of the Pancreas and Nonfunctional Pancreatic Neuroendocrine Neoplasm Using Endoscopic Ultrasound

OBJECTIVES

We investigated the utility of endoscopic ultrasound (EUS) for differentiating between solid pseudopapillary neoplasm of the pancreas (SPN) and pancreatic neuroendocrine neoplasm (PanNEN).

METHODS

A retrospective analysis was performed on 29 and 77 consecutive patients with pathologically proven SPN and nonfunctional PanNEN. In patients who underwent contrast-enhanced harmonic EUS (CH-EUS), lesions were classified into 3 vascular patterns (hypoechoic/isoechoic/hyperechoic), and the presence of "the alveolus nest sign," which we previously reported as a characteristic feature of SPN on CH-EUS, was also assessed.

RESULTS

Conventional EUS findings showed that calcification echoes were significantly more frequent in SPN lesions than in PanNEN lesions (19/29 [66%] vs 21/77 [27%], P = 0.001) as was internal isoechogenicity or hyperechogenicity (10/29 [34%] vs 11/77 [14%], P = 0.029). Contrast-enhanced harmonic EUS findings showed that SPN lesions more frequently had the isoechoic or hypoechoic vascular pattern, and significantly more frequently had the alveolus nest sign (18/25 [72%] vs 4/60 [7%], P < 0.001). In a multivariate analysis, the presence of the alveolus nest sign contributed the most to the SPN diagnosis (odds ratio, 70; 95% confidence interval, 6.2-786).

CONCLUSIONS

Endoscopic ultrasound, particularly the presence of the alveolus nest sign on CH-EUS, is useful for differentiating SPN from PanNEN.

Solid pseudopapillary neoplasm of the pancreas in a young male with main pancreatic duct dilatation: A case report

BACKGROUND

Solid pseudopapillary neoplasms (SPNs) are rare tumors of the pancreas. Typically, they occur in young females, often have characteristic imaging features, such as cystic components and calcification, and have few effects on the pancreatic duct.

CASE SUMMARY

A 31-year-old man was admitted to our hospital with the chief complaint of epigastric pain. There was only mild tenderness in his upper abdomen, and blood tests showed only a slight increase in alkaline phosphatase. Contrast-enhanced computed tomography showed a 40-mm-diameter, hypovascular mass in the head of the pancreas, and the main pancreatic duct upstream of the mass was severely dilated. Magnetic resonance imaging showed low intensity on T1-weighted images, with high intensity on T2-weighted image in some parts. Pancreatic ductal adenocarcinoma was the primary differential diagnosis. Portal vein infiltration could not be ruled out, so this case was a candidate for neoadjuvant chemotherapy. Subsequently, endoscopic ultrasound-guided fine needle aspiration was performed, and pathological evaluation and immunostaining suggested a diagnosis of SPN. Thus, pancreatoduodenectomy was performed. One year after the operation, the patient is alive with no recurrence.

CONCLUSION

Main pancreatic duct dilatation is usually a finding of suspected pancreatic cancer. However, pancreatic duct dilatation can occur in SPN depending on the location and growth speed. Therefore, SPN should be considered in the differential diagnosis of tumors with pancreatic duct dilatation, and pathological evaluation by endoscopic ultrasound-guided fine needle aspiration should be actively performed.

Pancreatic solid pseudopapillary neoplasm: a single-institution study

BACKGROUNDS

Solid pseudopapillary neoplasms (SPNs) are a distinct but rare form of low-grade pancreatic neoplasia, accounting for 0.3%-2.7% of all pancreatic tumours. They are most common in young females. Local recurrence and distant metastasis are reported but extremely rare, and are usually resectable with curative intent. We report the clinicopathological features and long-term outcomes of SPNs following surgical resection from a single institution.

METHODS

A total of 1296 patients undergoing pancreatic resection during the 30 years period from 1991 to 2020 were retrospectively reviewed, and those with a confirmed pathological diagnosis of pancreatic SPN on review were included.

RESULTS

Twenty-two patients (1.7% of all patients undergoing resection), were identified. Twenty patients (91%) were female. Unlike previous studies, most patients (91%) were symptomatic at diagnosis. On diagnostic CT, cystic components were visible in 16 patients (73%), calcifications were found in two patients (9%), haemorrhage in one patient (5%) and a defined capsule was seen in four patients (18%). Surgical resection was undertaken on all cases, with distal pancreatectomy the most commonly performed (n = 11, 50%). One patient (4.7%) had nodal involvement, nine patients had an incomplete tumour capsule (41%) and seven patients (32%) had tumour extension into the pancreatic parenchyma. Despite this, no patients had disease recurrence at 10 years. One patient died within 5 years of heart failure unrelated to the SPN process; no patients died within 10 years of the disease.

CONCLUSION

We confirm a high proportion of female patients. Interestingly, a high proportion of our cohort was investigated for symptomatic disease. Despite a high proportion of tumours with an incomplete capsule, and extension into the pancreatic parenchyma, our findings indicated that SPN patients have excellent survival after margin-negative surgical resection.

Pancreatic acinar cell carcinoma with extension into the main pancreatic duct: a case report

Background

Pancreatic acinar cell carcinoma (PACC) is a rare exocrine malignant tumor. Its widespread intraductal extension into the main pancreatic duct (MPD) is also rare.

Case presentation

We report the case of a 71-year-old man with PACC with MPD extension. The patient was assessed with laboratory and radiographic investigations that facilitated a preoperative diagnosis. Endoscopic ultrasonography (EUS) and dynamic thin-slice multi-detector row computed tomography (MDCT) were useful for determining the resection line of the pancreas. EUS-guided fine needle aspiration (EUS-FNA) was also helpful in determining the tumor biology and treatment strategy. Distal pancreatectomy was performed. The MPD was occupied by the tumor 35 mm downstream and 5 mm upstream. Histopathologically, the pancreatic tail tumor extended continuously into the MPD. The tumor was solid with cells showing eosinophilic and granular cytoplasm, indicating the diagnosis of PACC. This is an interesting case of PACC with intraductal extension into the MPD. We discuss the possible mechanisms of tumor extension in this rare case together with a review of the literature.

Conclusions

We describe a rare pancreatic acinar cell carcinoma that could be adequately treated using preoperative precise imaging and histopathological evaluations. When an intraductal tumor extension in the MPD is encountered, the diagnosis of a rare pancreatic tumor should be considered, as in our case.

Diagnosis of Pancreatic Solid Lesions, Subepithelial Lesions, and Lymph Nodes Using Endoscopic Ultrasound

Currently, endoscopic ultrasound (EUS) has become widely accepted and has considerable advantages over computed tomography (CT) and other imaging modalities, given that it enables echostructure assessment in lesions with <1 cm diameter and permits high resolution imaging. EUS-guided tissue acquisition (EUS-TA) provides consistent results under ultrasound guidance and has been considered more effective compared to CT- or ultrasound-guided lesion biopsy. Moreover, complication rates, including pancreatitis and bleeding, have been extremely low, with <1% morbidity and mortality rates, thereby suggesting the exceptional overall safety of EUS-TA. The aggressive use of EUS for various lesions has been key in facilitating early diagnosis and therapy. This review summarizes the diagnostic ability of EUS for pancreatic solid lesions, subepithelial lesions, and lymph nodes where it is mainly used. EUS has played an important role in diagnosing these lesions and planning treatment strategies. Future developments in EUS imaging technology, such as producing images close to histopathological findings, are expected to further improve its diagnostic ability. Moreover, tissue acquisition via EUS is expected to be used for precision medicine, which facilitates the selection of an appropriate therapeutic agent by increasing the amount of tissue collected and improving genetic analysis.

Evaluation of endoscopic ultrasound-guided fine-needle biopsy for preoperative pancreatic solid lesions

OBJECTIVES

Obtaining an accurate preoperative diagnosis is crucial. This study aimed to evaluate the diagnostic accuracy and utility of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) for preoperative pancreatic solid lesions.

MATERIALS AND METHODS

We retrospectively assessed all patients who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) or EUS-FNB to evaluate solid pancreatic lesions preoperatively at our center between July 2013 and June 2020. We enrolled 71 patients who underwent EUS-FNA using a 22 G conventional needle (FNA group) and 34 patients who underwent EUS-FNB using a 22 G Franseen needle (FNB group). Overall, 105 patients were analyzed. We employed propensity-matched analysis and adjusted the confounders.

RESULTS

No procedural adverse events were encountered. Both groups showed no significant differences in the procedure time, technical success rate, and rate of operator changes from trainee to expert. Regarding diagnostic accuracy, the FNB group (88.2%; 30/34) was higher but not significantly different from the FNA group (85.3%; 29/34) (p > .99). Furthermore, the FNB group (median 2, IQR;2-3) had a significantly lower number of punctures than the FNA group (median 3, IQR; 2-4) (p = .01).

CONCLUSIONS

The FNB needle provides higher diagnostic accuracy and requires significantly fewer punctures than conventional needles even at facilities with no available rapid on-site evaluation. Thus, using the FNB needle can be useful for preoperative pancreatic solid lesions.

Peritoneal dissemination of pancreatic cancer caused by endoscopic ultrasound-guided fine needle aspiration: A case report and literature review

BACKGROUND

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a biopsy technique widely used to diagnose pancreatic tumors because of its high sensitivity and specificity. Although needle-tract seeding caused by EUS-FNA has been recently reported, dissemination of pancreatic cancer cells is generally considered to be a rare complication that does not affect patient prognosis. However, the frequency of dissemination and needle-tract seeding appears to have been underestimated. We present a case of peritoneal dissemination of pancreatic cancer due to preoperative EUS-FNA.

CASE SUMMARY

An 81-year-old man was referred to the Department of Surgery of our hospital in Japan owing to the detection of a pancreatic mass on computed tomography during medical screening. Trans-gastric EUS-FNA revealed that the mass was an adenocarcinoma; hence laparoscopic distal pancreatectomy with lympha-denectomy was performed. No intraoperative peritoneal dissemination and liver metastasis were visually detected, and pelvic lavage cytology was negative for carcinoma cells. The postoperative surgical specimen was negative for carcinoma cells at the dissected margin and the cut end margin; however, pathological findings revealed adenocarcinoma cells on the peritoneal surface proximal to the needle puncture site, and the cells were suspected to be disseminated via EUS- FNA. Hence, the patient received adjuvant therapy with S-1 (tegafur, gimeracil, and oteracil potassium); however, computed tomography performed 5 mo after surgery revealed liver metastasis and cancerous peritonitis. The patient received palliative therapy and died 8 mo after the operation.

CONCLUSION

The indications of EUS-FNA should be carefully considered to avoid iatrogenic dissemination, especially for cancers in the pancreatic body or tail.

Huge solid pseudopapillary tumor of the pancreas 'Frantz tumor': a case report

Solid pseudopapillary neoplasms (SPN) of the pancreas are rare neoplasms accounting for 1-2% of all pancreatic tumors and have a general female predominance. We report a case and intraoperative videos of SPN involving the whole pancreatic tail. A 19-year-old female patient initially presented to another healthcare facility complaining of abdominal pain, which was started 6 years ago. A contrast-enhanced Computed Tomography (CT) scan of the abdomen showed a large mass measuring 15.6 cm × 11.6 cm × 11 cm, arising from the pancreas with an enhancing cystic component. The patient underwent exploratory laparotomy, which revealed a huge mass occupying most of the abdominal cavity. Thus, we proceeded with a distal pancreatectomy and splenectomy. Intraoperatively, the frozen section showed that the mass had features of a solid pseudopapillary tumor of the pancreas with negative resection margins. The SPN diagnosis was confirmed by histopathology and immunohistochemistry. The pathophysiology behind the development of SPN and its cellular origin is still a matter of debate with multiple proposed hypotheses. SPNs are asymptomatic in almost 70% of all cases and usually discovered incidentally. The pre-operative diagnosis of SPNs remains a clinical challenge despite all the current advances in the diagnostic modalities. Surgical management with negative resection margins is the mainstay of treatment, even with metastasis and vascular invasion, surgical excision should be performed whenever feasible. The recurrence rate after surgical resection has been reported to be 3-9%. The prognosis of SPN limited to the pancreas is generally excellent with over 95% cure rate following complete surgical resection. SPN is a rare entity of a controversial origin but is considered as a low-grade malignancy. Surgical resection to achieve complete excision constitutes the mainstay of treatment, which mostly results in an excellent prognosis.

Complications of Endoscopic Ultrasound-Guided Fine Needle Aspiration: A Narrative Review

Considerable progress has been made recently in the use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to diagnose intra-luminal gastrointestinal lesions and extra-luminal lesions near the gastrointestinal tract. Numerous reports have indicated that EUS-FNA has high diagnostic performance and safety, which has led to the routine use of EUS-FNA and an increasing number of cases. Thus, while EUS-FNA has a low rate of complications, endoscopists may encounter these complications as the number of cases increases. Infrequent reports have also described life-threatening complications. Therefore, endoscopists should possess a comprehensive understanding of the complications of EUS-FNA, which include hemorrhage, perforation, infection, and acute pancreatitis, as well as their management. This review examines the available evidence regarding the complications associated with EUS-FNA, and the findings will be useful for ensuring that endoscopists perform EUS-FNA safely and appropriately.

Quality in pancreatic endoscopic ultrasound: what's new in 2020?

Quality assessment and improvement of an endoscopic service has emerged as a basic component of everyday gastrointestinal endoscopy. In order to ensure a high level of quality, a series of actions must be adopted when performing an endoscopic examination. Nonetheless, quality still remains a qualitative parameter; thus, implementation of specific indicators of quality is warranted. Irrespective of the nature of the endoscopic procedure, quality indicators usually refer to either structural properties of an endoscopy unit (e.g., examination availability), procedural factors (e.g., diagnostic accuracy), or patient outcomes (e.g., occurrence of an adverse event related to performance of an endoscopic procedure). Moreover, they are usually classified into 3 distinct sections, according to the phase of the procedure they relate to: i.e., before, during, and after the examination. The aim of this review is to present measures that need to be adopted in order to reach an optimal quality level during an endoscopic ultrasound examination and to provide up-to-date data regarding the respective quality indicators implicated.

Overlooked risk for needle tract seeding following endoscopic ultrasound-guided minimally invasive tissue acquisition

Endoscopic ultrasound-guided minimally invasive tissue acquisition can be performed by two approaches as follows: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). These have been evolved into leading approaches and widely used for the histological diagnosis of tumors in the gastrointestinal tract and adjacent organs. However, the role of EUS-FNA and EUS-FNB in disease diagnosis and evaluation remains controversial. Although the incidence of surgery-associated complications remains low, the consequences of needle tract seeding can be serious or even life-threatening. Recently, increasing case reports of needle tract seeding are emerging, especially caused by EUS-FNA. This complication needs serious consideration. In the present work, we integrated these case reports and the related literature, and summarized the relevant cases and technical characteristics of needle tract seeding caused by EUS-FNA and EUS-FNB. Collectively, our findings provided valuable insights into the prevention and reduction of such serious complication.