Monica Pandolfi

Extracorporeal shock wave lithotripsy of pancreatic stones in chronic pancreatitis: immediate and medium-term results

BACKGROUND Obstruction of the main pancreatic duct with upstream hypertension and dilation is a cause of pain in patients with chronic pancreatitis. Pancreatic ductal drainage can be achieved endoscopically by intraductal stone removal after endoscopic pancreatic sphincterotomy and/or by insertion of a pancreatic stent. Extracorporeal shock wave lithotripsy may be needed whenever stones cannot be removed by endoscopic procedures. We present our results in 35 patients treated with a combined endoscopic-extracorporeal shock wave lithotripsy approach with at least 6 months of follow-up. METHODS Thirty-five patients with severe chronic pancreatitis were treated by extracorporeal shock wave lithotripsy for endoscopically unretrievable obstructive stones. Extracorporeal shock wave lithotripsy was performed with an electromagnetic lithotriptor in 29 patients and an electrohydraulic lithotriptor in 6. RESULTS The procedures were well tolerated by the majority of patients. Fragmentation of stones was obtained in all cases while complete clearance and decompression of pancreatic duct were obtained in 26 of 35 (74.3%) and in 30 of 35 (85.7%) cases, respectively. There was no mortality related to the procedure. Morbidity was observed in 8 of 35 patients (22.8%). CONCLUSIONS Extracorporeal shock wave lithotripsy is a safe and effective treatment for endoscopically unretrievable pancreatic stones in the main pancreatic duct. Extracorporeal shock wave lithotripsy should be considered complementary and not an alternative to endoscopic drainage. Combined with endoscopy, extracorporeal shock wave lithotripsy may increase the success rate of nonsurgical treatment of patients with chronic pancreatitis.

Endotherapy of postoperative biliary strictures with multiple stents: results after more than 10 years of follow-up

BACKGROUND Endoscopic dilation of postoperative biliary strictures with increasing numbers of stents was first described by our group in 2001 with promising results after a long-term follow-up (mean 4 years). OBJECTIVE To verify results of endoscopic treatment of postoperative biliary strictures at a very-long-term follow-up. DESIGN Single center, follow-up study. SETTING Tertiary-care, academic referral center. PATIENTS A group of 42 patients from our 2001 study, who had undergone endoscopic dilation of postoperative biliary strictures with the multiple endoscopic stenting technique, underwent systematic follow-up. The last telephone follow-up was done in September 2009. INTERVENTION Clinical conditions and the occurrence of new biliary symptoms during the follow-up period were assessed, and results of the most recent liver function tests and abdominal US were recovered. MAIN OUTCOME MEASUREMENTS Occurrence of cholangitis and liver function test evaluation during the follow-up period. RESULTS Of the 40 patients who were alive at the end of the study published in 2001, 5 (12.5%) died of unrelated causes after a mean of 6.7 years (range 3-13.3 years) from the end of treatment, without further biliary symptoms. The overall mean follow-up time for the remaining 35 patients (87.5%) was 13.7 years (range 11.7-19.8 years). Seven patients (20%) experienced recurrent acute cholangitis after a mean of 6.8 years (range 3.1-11.7 years) from the end of treatment. All 7 of these patients underwent ERCP. Four of the 7 patients had postoperative biliary stricture recurrence (n = 4/35, 11.4%) that was retreated endoscopically with placement of stents, and the other 3 patients had common bile duct stones (n = 3/35, 8.6%) that were extracted. No stricture or bile duct stone recurrences after retreatment were recorded after a mean follow-up period of a further 7.1 years (range 2.5-12.1 years). Twenty-eight patients remained asymptomatic with normal liver function test results and abdominal US results after a mean follow-up period of 13.7 years (range 11.7-19.8 years). LIMITATIONS Telephone follow-up. CONCLUSION Results of multiple endoscopic stenting for postoperative biliary strictures remain excellent even after a very-long-term follow-up. The stricture recurrence rate is low, and recurrences can be retreated endoscopically.

Efficacy of main pancreatic-duct endoscopic drainage in patients with chronic pancreatitis, continuous pain, and dilated duct

BACKGROUND The aim of endoscopic treatment in patients with chronic pancreatitis is to achieve decompression of the pancreatic duct, because duct obstruction with increased pressure within the duct is one of the leading causes of pain in these patients. The majority of patients suffer from relapsing pain, thus making it difficult to evaluate the efficacy of therapy. The outcome of endoscopic treatment on pain has been evaluated in patients with continuous pain (present for more than 1 month, at least 5 days per week, requiring daily analgesic therapy) and dilated duct. METHODS Of 343 patients who underwent endotherapy for chronic pancreatitis in a 15-year period, 22 (6.4%)(19 men, mean age 48 years, alcohol abuse 14) had continuous pain and a dilated pancreatic duct. RESULTS Endotherapy was successful in all patients, with no procedure-related mortality and only mild complications. Pain disappeared, and analgesics could be discontinued in all patients immediately after endotherapy. Six patients are pain free after a mean period of 5.5 years. One pain-free patient died after 3.4 years from myocardial infarction. Five patients were successfully endoscopically re-treated for pain relapses. Four patients underwent surgery for frequent pain relapses after a mean period of 2.5 years. Six patients were lost to follow-up. CONCLUSIONS Endotherapy should be considered as the initial treatment of choice in patients with chronic pancreatitis, dilated duct, and continuous pain.

Endoscopic stenting for biliary and pancreatic malignancies.

Endoscopic treatment of pancreatobiliary malignancies has been recognized in the last decades as the treatment of choice in inoperable patients. Endoscopic armamentarium includes biliary stents (plastic and metallic) to bypass neoplastic strictures of the biliary tree, and pancreatic stents to palliate the obstructive pain caused by stenoses of the main pancreatic duct. A major issue is the long-term patency of plastic stents that will eventually clog on average after 3 to 4 months. Self-expandable metallic stents have longer patency, but they can also become occluded by tumor ingrowth or overgrowth; they are also much more expensive; their use is thus recommended in patients with longer life expectancy. Decompression of the dilated main pancreatic duct in pancreatic carcinoma may be effective in the relief of obstructive pain. Endoscopic palliation in pancreatic and biliary malignancies appears safe and effective; management of patient in referral centers, with an available team of gastroenterologists with endoscopic skills, surgeons, and radiologists is recommended.

EUS-guided Nd:YAG laser ablation of normal pancreatic tissue: a pilot study in a pig model.

BACKGROUND Laser ablation with a neodymium:yttrium aluminum garnet (Nd:YAG) laser can achieve a high rate of complete tissue necrosis and has been applied as a minimally invasive, palliative option in hepatocellular carcinoma, liver metastasis in colorectal cancer, and malignant thyroid nodules. OBJECTIVE To assess the in vivo feasibility of EUS-guided laser ablation with an Nd:YAG laser of normal pancreatic tissue of a porcine model. DESIGN Prospective investigation. SETTING Hospital animal laboratory. SUBJECTS Eight pigs. INTERVENTIONS EUS-guided puncture of the pancreatic tail with a laser-beam fiber. An Nd:YAG laser (1.064 nm) was used, with an output power of 2 and 3 W and a total delivered energy of 500 and 1000 J in continuous mode. MAIN OUTCOME MEASUREMENTS The 24-hour follow-up of the pigs was focused on clinical and laboratory aspects. Results of histological studies of the pancreas were obtained 24 hours after the procedure on necroscopy tissue. RESULTS There were no technical limitations to the performance of the procedure. Tissue necrosis, localized in the pancreatic parenchyma, was observed in all animals on histological examination. The volume of ablation tissue ranged from a mean of 314 mm(3) to 483 mm(3). The ablation area ranged from a mean of 49 mm(2) to 80 mm(2). No major postprocedure complications were recorded, and all the pigs survived at 24 hours. LIMITATION Animal study. CONCLUSIONS EUS-guided laser ablation of the pancreas with an Nd:YAG laser is feasible in a porcine model.

EUS-guided Nd:YAG laser ablation of a hepatocellular carcinoma in the caudate lobe

Vascular liverinjuries and portobiliary fistulas related to biliary proceduresappear to be a more recognized complication of percutane-ous biliary drainage rather than ERCP. However, this casereport illustrates that if the apparent biliary anatomy looksunusual, particularly if radiographic contrast material washesout from the biliary tree, then entry into the portal vein haslikely occurred, a diagnosis of portobiliary fistula should beconsidered, and stent placement should take place only withcaution. As in this case, if a stent has been placed previously,then further stenting may be needed to occlude the fistula. Inthe occurrence of a portobiliary fistula, biliary stenting viaeither ERCP or percutaneous transhepatic cholangiographyoffers an opportunity to prevent significant hemorrhage andpotential portal sepsis.

Laser Interstitial Thermotherapy for pancreatic tumor ablation: Theoretical model and experimental validation

This study aims to develop and verify a theoretical model to reproduce the thermal response of pancreatic tissue undergone Laser Induced Interstitial Thermotherapy (LITT). The model provides the evaluation of: a) ablated volumes induced by thermal ablation; b) tissue response time to irradiation; and c) heat extinction time. Theoretical volume values were compared with ex vivo healthy tissue and in vivo healthy and neoplastic tissue volume values. The theoretical model takes into account the differences between healthy and neoplastic tissue due to blood perfusion. Mathematical model shows that ablated volume of ex vivo healthy tissue is greater than in vivo one after the same treatment. Moreover, ablated neoplastic in vivo tissue volume is greater than healthy in vivo one, because of tumour angiogenesis. Ablated volume values were compared with experimental data obtained by laser treatment of 30 ex vivo porcine pancreases. Experimental ablated volume values show a good agreement with theoretical values, with an estimated increase of 61% when power increases from 3 W to 6 W, versus 46% of experimental data, and an estimated increase of 14% from 6 W to 10 W, versus 21% of experimental values. LITT could be an alternative or a neo-adjuvant treatment to surgical resection for pancreas cancer removal, and the proposed model could be the basis to supervising the evolution of ablated volumes during tumor treatment.

US-guided application of Nd:YAG laser in porcine pancreatic tissue: an ex vivo study and numerical simulation

BACKGROUND Laser ablation (LA) with a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser is a minimally invasive approach able to achieve a high rate of complete tissue necrosis. In a previous study we described the feasibility of EUS-guided Nd:YAG pancreas LA performed in vivo in a porcine model. OBJECTIVE To establish the best laser setting of Nd:YAG lasers for pancreatic tissue ablation. A secondary aim was to investigate the prediction capability of a mathematical model on ablation volume. DESIGN Ex vivo animal study. SETTING Hospital animal laboratory. SUBJECTS Explanted pancreatic glands from 60 healthy farm pigs. INTERVENTION Laser output powers (OP) of 1.5, 3, 6, 10, 15, and 20 W were supplied. Ten trials for each OP were performed under US guidance on ex vivo healthy porcine pancreatic tissue. MAIN OUTCOME MEASUREMENTS Ablation volume (Va) and central carbonization volume (Vc) were measured on histologic specimens as the sum of the lesion areas multiplied by the thickness of each slide. The theoretical model of the laser-tissue interaction was based on the Pennes equation. RESULTS A circumscribed ablation zone was observed in all histologic specimens. Va values grow with the increase of the OP up to 10 W and reach a plateau between 10 and 20 W. The trend of Vc values rises constantly until 20 W. The theoretical model shows a good agreement with experimental Va and Vc for OP between 1.5 and 10 W. LIMITATIONS Ex vivo study. CONCLUSION Volumes recorded suggest that the best laser OP could be the lowest one to obtain similar Va with smaller Vc in order to avoid the risk of thermal injury to the surrounding tissue. The good agreement between the two models demonstrates the prediction capability of the theoretical model on laser-induced ablation volume in an ex vivo animal model and supports its potential use for estimating the ablation size at different laser OPs.

Endoscopic full-thickness resection of superficial colorectal neoplasms using a new over-the-scope clip system: A single-centre study

BACKGROUND AND AIM Endoscopic full-thickness resection (EFTR) provides complete en-bloc resection with a histopathological evaluation of submucosal, muscular, and serosal layers. The aim of this study was to investigate the efficacy and safety of a novel over-the-scope device for colorectal EFTR. MATERIAL AND METHODS In this retrospective, observational, open-label case study, a total of 20 patients with superficial colorectal neoplasms, underwent EFTR using a new endoscopic full-thickness resection device (FTRD; Ovesco Endoscopy, Tübingen, Germany). Endoscopic treatment outcomes (technical success, rate of EFTR, adverse events) and early follow-up at three months, were analyzed. RESULTS We reported a 100% of technical success, defined as full-thickness resection. Among the R1 resections, histology was negative for neoplasm. Non-lifting adenomas had histology positive for adenocarcinoma: seven T1/G1/sm1; one T1/G1/sm2; one, who underwent a surgical resection, T1/G1/sm3. Mean size of the resected lesions was 26mm, ranging from 10 to 42mm. One (5%) patient developed abdominal pain, fever and leukocytosis and was treated conservatively with medical therapy. In all specimens, histological complete resection was confirmed. CONCLUSIONS EFTR is a feasible and effective technique that could become a valid alternative to EMR and ESD in the management of recurrent adenomas, no-lifting lesions and scars of R1 resections. However, prospective studies are needed to further evaluate the device and technique.