EUS-guided alcohol ablation of an insulinoma

Endoscopic ultrasonography-guided ethanol lavage with paclitaxel injection treats patients with pancreatic cysts

BACKGROUND & AIMS

Endoscopic ultrasonography (EUS)-guided interventions have been used to treat patients with cystic lesions of the pancreas (CLPs). We used EUS to guide injection and lavage of ethanol, followed by injection of paclitaxel, into cysts, and investigated treatment response and predictors.

METHODS

Fifty-two patients were enrolled in the study using the following inclusion criteria: unilocular or oligolocular cysts, indeterminate cystic lesions that required EUS fine-needle aspiration, and cystic lesions that grew during the observation period. Forty-seven patients were followed up for more than 12 months and their outcomes were analyzed.

RESULTS

The mean diameter of the CLPs was 31.8 mm (range, 17-68 mm) and the estimated volume was 14.09 mL (range, 1.16-68.74 mL). Twenty CLPs were oligolocular. The mean level of carcinoembryonic antigen was 463 ng/mL (range, 1-8190 ng/mL). The median follow-up period was 21.7 months. A complete response was observed in 29 patients, a partial response in 6 patients, and persistent cysts in 12 patients. Four of 12 patients with persistent cysts underwent surgery. The histopathologic degree of epithelial ablation varied from 0% to 100%. Based on univariate analysis, EUS diameter and original volume predicted cyst resolution; in multivariate analysis, only original volume predicted resolution. Mild pancreatitis and splenic vein obliteration each occurred in 1 patient.

CONCLUSIONS

EUS-guided injection and lavage of ethanol, followed by injection of paclitaxel, appears to be a safe method for treating pancreatic cysts; 62% of patients had complete resolution. Small cyst volume predicted complete resolution.

Role of pancreatic endoscopic ultrasonography in 2010

Endoscopic ultrasonography (EUS) was introduced 25 years ago aiming at better visualization of the pancreas compared to transabdominal ultrasonography. This update discusses the current evidence in 2010 concerning the role of EUS in the clinical management of patients with pancreatic disease. Major indications of EUS are: (1) Detection of common bile duct stones (e.g. in acute pancreatitis); (2) Detection of small exo- and endocrine pancreatic tumours; and (3) Performance of fine needle aspiration in pancreatic masses depending on therapeutic consequences. EUS seems to be less useful in cases of chronic pancreatitis and cystic pancreatic lesions. Moreover the constant improvement of computed tomography has limited the role of EUS in pancreatic cancer staging. On the other hand, new therapeutic options are available due to EUS, such as pancreatic cyst drainage and celiac plexus neurolysis, offering a new field in which new techniques may arise. So the main goal of this review is to determine the exact role of EUS in a number of pancreatic and biliary diseases.

EUS-Guided Antitumor Therapy for Pancreatic Tumors

Endoscopic ultrasound (EUS) is a very useful modality for the diagnosis and staging of pancreatic masses. With the advent of EUS-guided fine-needle aspiration technology, this modality has made a tremendous leap from imaging modality to histologic diagnosis and therapeutic intervention. EUS offers high-resolution images of and unparalleled access to the pancreas. After locating the tip of the echoendoscope in the duodenum or stomach, several drugs or local treatment modalities can be delivered directly into the pancreas. EUS-guided ethanol lavage with/without paclitaxel injection has been tested for the treatment of cystic tumors of the pancreas, with complete resolution of cystic tumor being observed in up to 70-80% of patients. Ethanol injection is also performed for the management of solid neuroendocrine tumors of the pancreas. Various type of EUS-guided injection have also been investigated for the treatment of pancreatic cancer. An activated allogenic mixed lymphocyte culture (Cytoimplant) was injected in patients with advanced pancreatic cancer. A replication-deficient adenovirus vector carrying the tumor necrosis factor-alpha gene was also delivered intratumorally by EUS. ONYX-015 is an oncolytic attenuated adenovirus that exhibits replication preferentially in malignant cells, causing cell death, and this has also been injected into pancreatic cancers under EUS guidance. EUS-guided local ablation therapies such as radiofrequency ablation, photodynamic therapy, and brachytherapy are also under investigation. EUS-guided fine-needle injection for various solid or cystic lesions is a rapidly expanding field. This article reviews the various applications of EUS for the treatment of pancreatic tumors.

[Hypoglycemia and insulinoma]

Insulinomas are rare causes of hypoglycemia. After having ruled out non insulinomatous causes of hypoglycemia in a patient in whom Whipple's triad is documented, hyperinsulinism must be demonstrated biochemically, either during a spontaneous hypoglycemic episode or, more often, during a supervised fast which may be prolonged up to 72 h. A mixed-meal test may also help to diagnose the very rare cases of postprandial hypoglycemia related to non insulinoma pancreatogenic hypoglycemic syndrome (NIPHS) or to some rare insulinomas. Only when diagnosis of hypoglycemic hyperinsulinism is made, the tumor localization process may be initiated. This may be difficult due to the small size of insulinomas (generally < 1 cm). Multimodal approach is necessary. The association of endoscopic ultrasound and CT-scan or MRI seems optimal. Octreoscan will be also performed. First results with a very new technique, the GLP-1 receptor imaging, are promising for localizing very small tumors. This localization aims to allow a sparing surgery; enucleation of benign tumors, if possible, allows a pancreatic tissue preservation in patients with quite normal survival.

Endoscopic ultrasound: what is it and when should it be used?

Endoscopic ultrasound (EUS) is an increasingly available diagnostic and therapeutic tool used within the U.K. it has wide applications both in the gastrointestinal tract and mediastinum with its current main uses being in the staging of luminal malignancies and assessment of pancreatic and subepithelial lesions. The emergence of linear EUS has opened up new therapeutic avenues with fine needle aspiration, trucut biopsies, coeliac plexus blocks and transmural pseudocyst drainage all now possible. Future developments include localised brachytherapy/chemotherapy and alcohol ablation of unresectable pancreatic malignancies and EUS-guided endoscopic surgery.

EUS-guided ethanol versus saline solution lavage for pancreatic cysts: a randomized, double-blind study

BACKGROUND

Surgery for pancreatic cysts is associated with significant morbidity. A pilot study previously demonstrated the safety of EUS-guided ethanol lavage of pancreatic cysts.

OBJECTIVE

To determine whether EUS-guided ethanol lavage would decrease pancreatic cyst size more than saline solution lavage.

DESIGN

Prospective, multicenter, randomized trial.

SETTING

Two tertiary referral hospitals in the United States.

PATIENTS

Patients referred for EUS with a 1- to 5-cm unilocular pancreatic cyst were randomized to blinded ethanol or saline solution lavage. Three months later, the cyst diameter was remeasured by EUS, and a second unblinded ethanol lavage was performed.

INTERVENTIONS

EUS-guided pancreatic cyst lavage.

MAIN OUTCOME MEASUREMENTS

Cyst ablation based on size changes from follow-up EUS, CT, and histology of resected specimens.

RESULTS

Of 58 patients randomized, 16 were excluded and 42 underwent initial ethanol (n = 25) or saline solution (n = 17) lavage. Ethanol lavage resulted in a greater mean percentage of decrease in cyst surface area (-42.9; 95% CI, -58.4 to -27.4) compared with saline solution alone (-11.4; 95% CI, -25.0 to 2.2; P = .009). Nineteen (76.0%) of 25 and 14 (82.3%) of 17 patients randomized to ethanol and saline solution, respectively, underwent a second ethanol lavage. A follow-up CT scan demonstrated resolution in 12 (33.3%) of 36 cysts. Histology of 4 resected cysts demonstrated epithelial ablation ranging from 0% (saline solution alone) to 50% to 100% (1 or 2 ethanol lavages). Complication rates were similar in all groups.

LIMITATION

Short-term follow-up.

CONCLUSIONS

EUS-guided ethanol lavage results in a greater decrease in pancreatic cyst size compared with saline solution lavage with a similar safety profile. Overall CT-defined complete pancreatic cyst ablation was 33.3%.

Radiofrequency ablation of solitary pancreatic insulinoma in a patient with episodes of severe hypoglycemia

Insulinomas are rare neuroendocrine tumors of the pancreas. Therapy of first choice is the surgical resection or enucleation. In cases of metastases or in patients with high surgical risk, medical therapy with diazoxide or octreotide is an alternative. In this case, we describe the successful use of computed tomography (CT)-guided radiofrequency ablation (RFA) of an insulinoma in an 80-year-old female patient. The patient suffered from episodes of severe nightly hypoglycemia with a minimal glucose concentration of 1.95 mmol/l (36 mg/dl). An insulinoma measuring 1.5 cm in diameter was localized by endoscopic ultrasound and CT scan in the tail of the pancreas. Owing to a high surgical risk caused by the patient's comorbidities and poor physical condition, the resection of the tumor was not considered. The medical treatment with diazoxide failed to control the symptoms of hypoglycemia sufficiently. Using CT-guided percutaneous RFA, the insulinoma was successfully ablated. No postinterventional complications occurred. During a 5-week follow-up, episodes of hypoglycemia were absent. A control-CT, 5 weeks after RFA, revealed no residual tumor. In conclusion, we found RFA suitable for the treatment of pancreatic insulinomas. Until more data concerning efficacy and complication rates have been collected; the procedure should be reserved for the treatment of patients who are no candidates for surgical therapy and in whom symptoms cannot be controlled by the medical therapy.

Interventional endoscopic ultrasonography: applications for cancer related treatment

For tissue diagnosis in patients with abnormalities of various organs, endoscopic ultrasonography (EUS)-guided fine needle aspiration (EUS-FNA) has emerged as an effective technique. Subsequently, EUS-guided fine needle injection (EUS-FNI) has expanded the clinical utility of EUS. Several applications of EUS-FNI for anti-cancer efforts have included celiac nerve blocking and drug delivery into tumors, such as ablation, chemotherapy, gene therapy, and cytoimplantation. Furthermore, chemosensitivity tests with materials obtained using EUS-FNA are available to produce tailor-made medicines. Demonstrably, EUS-guided intervention has opened new and exciting clinical applications for the management of malignancies.

Interventional endoscopic ultrasonography

Endoscopic ultrasonography (EUS) is the combination of endoscopy and intraluminal ultrasonography. This allows use of a high frequency transducer, which, due to the short distance to the target lesion, enables ultrasonographic images of high resolution to be obtained. Endoscopic ultrasonography is now a widely accepted modality for the diagnosis of pancreatobiliary diseases. It can be used to determine the depth of invasion of gastrointestinal malignancies, and often for visualizing lesions more precisely than other imaging modalities. The most important early limitation of EUS was the lack of specificity in the differentiation between benign and malignant changes. In 1992, EUS-guided fine needle aspiration (EUS-FNA) of lesions in the pancreas head has been made possible using a curved linear array echoendoscope. Since then, many researchers have expanded the indication of EUS-FNA to various kinds of lesions and also for a variety of therapeutic purposes. In this review, we particularly focus on the present and future roles of interventional EUS, including EUS-FNA and therapeutic EUS.

Endoscopic ultrasound in pancreatic disease--its influence on surgical decision-making. An update 2008

Endoscopic ultrasonography (EUS) was introduced about 25 years ago with the primary aim of better visualization of the pancreas as compared to transabdominal ultrasonography. This review discusses the current evidence in 2008 concerning the role of EUS in the clinical management of patients, with a special emphasis on its impact on surgical therapy. According to the literature, good indications are detection of common bile duct stones (e.g. in acute pancreatitis), the detection of small exo- and endocrine pancreatic tumors, the performance of fine-needle aspiration in pancreatic masses depending on therapeutic consequences. In other areas such as diagnosis of chronic pancreatitis and cystic pancreatic lesions, the contribution of EUS seems limited. Pancreatic cancer staging is discussed controversially due to conflicting evidence and certainly has lost grounds due to improvements in CT technology. Therapeutic EUS is, however, more widely accepted and may replace other techniques, e.g. in pancreatic cyst drainage and celiac plexus neurolysis; further techniques of interest are being developed.

Neuroendocrine tumors of the pancreas: endoscopic diagnosis

PURPOSE OF REVIEW

Endoscopic ultrasound (EUS) is a valuable tool in the diagnosis and management of pancreatic neuroendocrine tumors. This review highlights advances over the last year in EUS in the evaluation of pancreatic neuroendocrine tumors.

RECENT FINDINGS

We will focus on recent findings regarding the accuracy of EUS, EUS-guided fine needle aspiration (EUS-fine needle aspiration), emerging cytologic markers obtained from fine needle aspiration samples, and the role of EUS screening for patients with multiple endocrine neoplasia type 1 syndrome. Additionally, we will introduce potential therapeutic EUS interventions in the treatment of pancreatic neuroendocrine tumors.

SUMMARY

The present review highlights recent advances in the utility of EUS in the clinical management of pancreatic neuroendocrine tumors. Key studies from the last year demonstrate the important role of EUS in the diagnosis, prognosis, and treatment of pancreatic neuroendocrine tumors.

Endoscopic ultrasound: moving from diagnostics to therapeutics

Endoscopic ultrasound was initially introduced in the 1980s as a diagnostic modality using echoendoscopes with radial scanning that permitted reconstruction of cross-sectional images similar to computed tomography The close proximity of the ultrasound transducer to the gastrointestinal wall and retroperitoneal structures allowed a detailed examination that is not possible with cross-sectional imaging such as computed tomography and magnetic resonance imaging. It proved to be highly accurate and useful in the staging of gastrointestinal malignancies, as well as in characterizing the nature of subepithelial lesions and disorders of the pancreaticobiliary system. The introduction of linear echoendoscopes facilitated fine needle aspiration because, with linear scanning, it was able to trace the path of the tip of the needle during the puncture process. In addition to being very useful for tissue acquisition for diagnostic purposes, the principles behind endoscopic ultrasound-guided fine needle aspiration paved the way for the development of therapeutic endoscopic ultrasound. Substances could now be delivered by endoscopic ultrasound into targeted areas, an example being an endoscopic ultrasound-guided celiac plexus block and neurolysis. In addition, the endoscopic ultrasound-guided puncture of fluid collections, abscesses and obstructed biliary and pancreatic ductal systems facilitated the passage of guidewires, thus allowing therapeutic drainage procedures to be performed using the Seldinger technique. This review summarizes the diagnostic capability of endoscopic ultrasound and then moves on to elaborate in detail its therapeutic capability and potential.

Sporadically occurring functional pancreatic endocrine tumors: review of recent literature

PURPOSE OF REVIEW

Pancreatic neuroendocrine tumors are rare neoplasms often associated with a clinical syndrome. Their rarity makes a comprehensive study difficult at any single institution, while their uniqueness makes them desirable for investigation. This review summarizes recent information and advancements concerning pancreatic neuroendocrine tumor diagnosis, imaging characteristics, treatment algorithms, and staging.

RECENT FINDINGS

Insulinomas and gastrinomas comprise the majority of functional pancreatic neuroendocrine tumors. Advances in their identification and diagnostic evaluation, imaging techniques, and treatment algorithms are presented. Furthermore, a new staging classification system has been proposed which may significantly improve the ability to conduct future multi-institutional investigations on pancreatic neuroendocrine tumors.

SUMMARY

Although rare, a thorough understanding of pancreatic neuroendocrine tumors is essential for all physicians due to the wide variety of symptoms with which patients present. Currently, patients are often misdiagnosed for extended periods of time. This review summarizes the recently published literature about diagnosis, imaging, treatment, and staging of pancreatic neuroendocrine tumors.

EUS-guided alcohol ablation of left adrenal metastasis from non-small-cell lung carcinoma

BACKGROUND

EUS presents an alternative access to the left adrenal, making it possible to perform echo-guided needle biopsies.

OBJECTIVES

We present a case of EUS-guided therapy as alcohol ablation of left adrenal metastases.

DESIGN AND PATIENT

A 52-year-old man was admitted to the hospital complaining of abdominal pain. CT scan revealed an invasive process in the left upper lobe of the lung and a mass in the left adrenal area that was considered highly suspicious for left adrenal metastases from the patient's lung carcinoma. Cytopathologic examination of EUS-guided FNA confirmed the diagnosis of left adrenal metastasis. Because the patient's main clinical symptom was disabling abdominal pain, we considered the possibility of injection of alcohol into the left adrenal metastases under EUS guidance to ablate the metastatic lesion and potentially relieve the abdominal pain. EUS-guided alcohol ablation was performed successfully. RESULTS AND MAIN OUTCOME MEASUREMENT: On follow-up 3 days after EUS-guided left adrenal ablation, the patient had no abdominal pain. He remained without abdominal pain after 30 and 60 days of follow-up.

LIMITATION

New technique with limited data.

CONCLUSION

EUS-guided alcohol ablation of left adrenal metastases in patients with non-small-cell lung cancer may provide palliation of cancer-related abdominal pain. There may be potential for combining this (minimally invasive and easily performed EUS-guided therapeutic) technique for ablation of solitary adrenal metastasis in patients with lung cancer with other modalities (e.g., surgery, radiation, or chemotherapy) directed toward the primary pulmonary malignancy and adjacent mediastinal disease.

Pancreatic endocrine tumors

Incidental, nonfunctional pancreatic endocrine tumors (PET) are observed with increasing frequency. Most are insulinomas. Endoscopic ultrasound with fine-needle aspiration plays a significant role in the localization and tissue diagnosis of PET. Establishing PET behavior as aggressive or indolent remains challenging especially preoperatively. Newer techniques including DNA and micro-RNA analysis may play a role in this arena. Small benign PET may be enucleated or removed laparoscopically. Surgery is the mainstay of treating advanced disease including those with metastases and Zollinger-Ellison syndrome. The management of multiple endocrine neoplasia type 1 continues to be a challenge, including treating symptoms, targeted resections, and close observation. Diagnosis, management, and prognostication of PET are under evolution and a number of changes in these fronts are anticipated.