LAPAROSCOPIC UNCINATECTOMY: A MORE CONSERVATIVE APPROACH TO THE UNCINATE PROCESS OF THE PANCREAS

Short-term outcomes of laparoscopic and robotic limited resections of pancreatic neuroendocrine tumours of the uncinate process: Report of six cases and review of the literature

INTRODUCTION

Minimally invasive surgery (MIS) for limited resections for pancreatic uncinate lesions is not widely performed but can adequately treat benign or low-grade malignant lesions. The aim of this study was to evaluate the short-term outcomes of MIS-limited pancreatic resections for patients with suspected pancreatic neuroendocrine tumours (PNETs).

PATIENTS AND METHODS

This was a retrospective study of six consecutive patients who underwent MIS for PNET within a single institution between 2017 and 2022.

RESULTS

Six patients underwent limited pancreas-preserving MIS of the uncinate process (uncinectomy or enucleation), of which two were performed through the robotic approach and four through laparoscopic approach. The median operation time was 212.5 (175-338.75) min, and the median blood loss was 50 (50-112.5) ml. The median post-operative hospital length of stay was 5.5 (3.75-11.5) days. Two patients (33.3%) had major post-operative morbidities (Clavien-Dindo ≥Grade 3). There were no open conversions or post-operative mortalities. Five patients had histologically proven Grade 1 neuroendocrine tumours. One was T2 and four were T1.

CONCLUSIONS

This study suggests that limited MIS resections of pancreatic uncinate PNETs are a feasible procedure with good patient outcomes. It offers a safe alternative to radical surgical resections like pancreatoduodenectomies in selected patients with low-grade malignant or benign tumours.

Experience in the resection of the uncinate process of the pancreas: Indications and results. Literature review

INTRODUCTION

The aim of our study is to assess the accumulated experience in the use of uncinatectomy (UC) as a parenchymal-sparing pancreatectomy technique.

METHOD

We have carried out a observational and descriptive study including restrospectively all the patients undergoing UC at Hospital Universitary de Bellvitge (HUB) and an exhaustive review of the cases described in the english literature.

RESULTS

From 2003 to 2019, seven patients have been operated by UC in the HUB with a diagnostic orientation of pancreatic lesion considered premalignant. All patients have presented morbidity, mainly in the form of postoperative pancreatic fistula, and none of them have presented endocrine or exocrine pancreatic insufficiency. Currently, all patients are alive and without recurrence of neoplastic disease. Another 29 cases have been described in the literature. Of all the cases (36 patients), the approach was minimally invasive (laparoscopic or robotic) in 6 patients (16.7%), leading to a shorter hospital stay. The global incidence of pancreatic fistula is 50%, with a re-admission rate of less than 10%, but without requiring re-intervention.

CONCLUSIONS

UC is an infrequent and poorly standardized technique for the resection of benign lesions or those with low potential for malignancy located in the uncinate process of the pancreas. Although it is associated with equal or greater morbidity than standardized resection techniques, it offers excellent preservation of endocrine and exocrine pancreatic function, with the consequent long-term benefit in the patients life quality.

Minimally Invasive Resection of the Uncinate Process of the Pancreas: Anatomical Considerations and Surgical Technique

BACKGROUND

Low-grade lesions may benefit from pancreatic-sparing techniques. Resection of the uncinate process is rarely performed and reported due to its complexity that requires careful patient selection and accurate knowledge of the pancreatic anatomy. This study describes relevant anatomical elements to safely perform this complex operation in the minimally invasive setting.

METHODS

In this study, consecutive patients undergoing resection of the uncinate process of the pancreas were studied. Patients undergoing open approach were used for comparison. Preoperative and intraoperative variables were recorded, and the diagnosis and tumor size were determined from the pathology reports. Immediate postoperative results and hospital stay were analyzed. Follow-up was used to assess long-term complications and endocrine and exocrine functions.

RESULTS

Twenty-nine patients underwent resection of the uncinate process. The median age was 57 years. There were 21 males and eight females. Twenty patients underwent minimally invasive resection (14 laparoscopic and six by robotic approach) and nine were operated by open approach. A clinically relevant postoperative pancreatic fistula was observed in one patient (3.4%). Biochemical leakage was present in 44.8% of our patients. Mean follow-up was 62 months (3-147). Two patients needed reoperation during follow-up. No patient presented exocrine or endocrine insufficiency during late follow-up.

CONCLUSION

Minimally invasive resection of the uncinate process of the pancreas is a complex but a feasible procedure that preserves the pancreatic endocrine and exocrine functions. This pancreas-sparing procedure is an interesting alternative to pancreaticoduodenectomy in selected patients.

MAGNETIC RESONANCE CHOLANGIOPANCREATOGRAPHY (MRCP) VERSUS ENDOSONOGRAPHY-GUIDED FINE NEEDLE ASPIRATION (EUS-FNA) FOR DIAGNOSIS AND FOLLOW-UP OF PANCREATIC INTRADUCTAL PAPILLARY MUCINOUS NEOPLASMS

Background:

Intraductal papillary mucinous tumor (IPMN) are being diagnosed with increasing frequency. Computerized tomography scanning is commonly used as the primary imaging modality before surgery nonetheless magnetic resonance cholangiopancreatography (MRCP) provides better characterization. Endosonography-guided fine needle aspiration (EUS-FNA) has emerged as a way to reach pathological diagnose.

Aim:

To compare results of both methods with surgical pathology findings for classification of IPMN.

Methods:

Thirty-six patients submitted to surgical resection with preoperative suspect of IPMN were submitted preoperatively to MRCP and EUS-FNA. Images obtained were analyzed according to a classification determined for each method. ROC curve was used for statistical analysis, that compared the images tests with the purpose of finding the best method for diagnosis and classification of IPMN.

Results:

Sixteen patients underwent pancreatoduodenectomy, 16 to subtotal pancreatectomy and only four laparotomy. Pathological diagnosis was IPMN (n=33) and pancreatic intraepithelial neoplasia type 2 (n=3). Twenty-nine revealed non-invasive neoplasia and invasive form in four patients. MRCP and EUS-FNA have correctly diagnosed and classified (type of IPMN), in 62.5% and 83.3% (p=0.811), the affected segment location in 69% and 92% (p=0.638) and identification of nodules and/or vegetation presence in 45% and 90% (p=0.5). Regarding to histopathological diagnosis by EUS-FNA the sensitivity was 83.3%; specificity was 100%; positive predictive value was 100%; negative predictive value was 33.3% and accuracy was 91.7%.

Conclusions:

There was no significant difference in the diagnosis of IPMN. However, EUS-FNA showed better absolute results than MRCP to identify nodule and/or vegetation.

PANCREATIC NEUROENDOCRINE TUMORS: SURGICAL RESECTION

INTRODUCTION

Pancreatic neuroendocrine tumors (pNET) correspond to about 3% of all tumors in pancreas and could be presented as a difficult diagnosis and management.

OBJECTIVE

To review the diagnosis and treatment of the pNET available in scientific literature.

METHOD

A bibliographic survey was performed by means of an online survey of MeSH terms in the Pubmed database. A total of 104 articles were published in the last 15 years, of which 23 were selected as the basis for the writing of this article.

RESULTS

pNET is an infrequent neoplasia and their incidence, in USA, is about 1:100.000 inhabitants/year. Thereabout 30% of them produce hormones presenting as a symptomatic disease and others 70% of the cases could be silent disease. Magnetic Resonance Imaging (MRI) and/or Computed Tomography (CT) have similar sensitivy to detect pNET. They are very important when associated to nuclear medicine mainly Positron Emission Tomography (PET-CT) Gallium-68 to find primary tumor and its staging. The appropriate treatment should be chosen based on characteristics of the tumor, its staging and associated comorbidities.

CONCLUSION

The surgical resection is still the best treatment for patients with ressectable pancreatic NETs. However, the size, grade, tumor functionality, stage and association with multiple endocrine neoplasia type 1 (MEN-1) are important to define who will be eligible for surgical treatment. In general, tumors bigger than 2 cm are eligible for surgical treatment, except insulinomas whose surgical resection is recommended no matter the size.

Robotic resection of the uncinate process of the pancreas

Since the development of the robotic platform, the number of robotic-assisted surgeries has significantly increased. Robotic surgery has gained growing acceptance in recent years, expanding to pancreatic resection. Here, we report a total robotic resection of the uncinate process of the pancreas performed in a patient with a cystic neuroendocrine tumor. To our knowledge, this is the first report of a robotic resection of the uncinate process of the pancreas. A 46-year-old man with no specific medical history was diagnosed with a neuroendocrine tumor after undergoing routine imaging. Biopsy guided by echoendoscopy revealed a well-differentiated neuroendocrine tumor. We decided to perform a robotic resection of the uncinate process of the pancreas after obtaining informed consent for the procedure. According to preoperative echoendoscopy and magnetic resonance imaging, there was a safe margin between the neoplasm and the main pancreatic duct. The technique uses five ports. The duodenum is fully mobilized, and Kocher maneuver is carefully performed. The uncinate process of the pancreas is then identified. The resection of the uncinate process begins with the division of small arterial branches from the inferior pancreaticoduodenal artery in its inferior portion, followed by control of venous tributaries to the superior mesenteric vein. Intraoperative localization of the ampulla of Vater is performed using indocyanine green enhanced fluorescence, thus defining the superior margin of the uncinate process. The pancreatic division is made about 5 mm below its upper margin for safety. Surgical specimen is then retrieved through the umbilical port inside a plastic bag. The raw pancreatic area is covered with hemostatic tissue and drained. The total operation time was 215 min. The docking time was 8 min and console time was 180 min. Blood loss was minimum, estimated at less than 50 mL. The postoperative period was uneventful, except for hyperamylasemia in the drain fluid. The patient was discharged on the 3rd postoperative day. The final pathological report confirmed well-differentiated pancreatic neuroendocrine tumor. Robotic resection of the uncinate process of the pancreas is safe and feasible, providing parenchymal conservation in a minimally invasive setting. Robotic resection should be considered for patients suffering from low-grade pancreatic neoplasms located in this part of the pancreas.