Minimally Invasive Versus Open Pancreatic Surgery in Patients with Multiple Endocrine Neoplasia Type 1

[Individualized approach for MEN1-associated duodenopancreatic neuroendocrine neoplasms]

BACKGROUND

Multiple endocrine neoplasia type 1 (MEN1)-associated duodenopancreatic neuroendocrine neoplasms (dpNEN) represent the most frequent syndrome-associated cause of death, but the adequate treatment is sometimes considered controversial.

OBJECTIVE

Presentation of possible diagnostic and therapeutic options for MEN1-associated dpNENs.

MATERIAL AND METHODS

In this review article retrospective case studies, expert recommendations, national and international guidelines as well as personal experiences were analyzed and evaluated.

RESULTS

Due to early detection programs and the use of the most modern imaging techniques, dpNEN are nowadays diagnosed much earlier. Nonfunctional pNENs currently represent the most frequent dpNENs with about 70%, followed by gastrinomas and insulinomas. Regardless of their functional activity, dpNENs with a size of > 2 cm are generally an indication for surgery. The choice of the optimal treatment strategy, however, in most cases remains the subject of controversial discussions, although nowadays surgery should always be performed in an organ-preserving and minimally invasive way when feasible. Recurrences or new dpNENs are expected in more than 60% of cases, necessitating a reoperation in up to 40% of these cases. Duodenopancreatic resections and reoperations can be carried out safely by experienced practitioners and with an acceptable level of risk.

CONCLUSION

The planning of treatment requires careful consideration of the suitable timing, the extent of the operation, the risk of recurrence and potential morbidities. Furthermore, preserving pancreatic function and the quality of life is of utmost importance. In view of the complexity of the disease, MEN1 patients should be treated in specialized centers.

[Indication and Surgical Procedures for MEN1-associated Duodenopancreatic Neuroendocrine Neoplasms]

The optimal therapy of duodenopancreatic neuroendocrine neoplasia (dpNEN), which occurs in the context of multiple endocrine neoplasia type 1, is still a major challenge and is controversial. Due to the rarity of the disease, there is a lack of prospective randomised studies, so that most recommendations regarding the surgical indication and procedure are based on retrospective case series. In summary, surgical therapy is indicated for non-functional dpNEN > 2 cm, suspected malignancy and functionally active dpNEN. Enucleation or formal pancreatic resections with or without lymphadenectomy may be considered. The aim of therapy should be to eliminate hormone-associated symptoms and prevent an aggressive metastatic disease. At the same time, pancreatic function and quality of life should be preserved in the mostly young patients by resections that save as much parenchyma as possible.

Laparoscopic versus Open Pediatric Surgery: Three Decades of Comparative Studies

INTRODUCTION

 Despite its wide acceptance, the superiority of laparoscopic versus open pediatric surgery has remained controversial. There is still a call for well-founded evidence. We reviewed the literature on studies published in the last three decades and dealing with advantages and disadvantages of laparoscopy compared to open surgery.

MATERIALS AND METHODS

 Studies comparing laparoscopic versus open abdominal procedures in children were searched in PubMed/MEDLINE. Reports on upper and lower gastrointestinal as hepatobiliary surgery and on surgery of pancreas and spleen were included. Advantages and disadvantages of laparoscopic surgery were analyzed for different types of procedures. Complications were categorized using the Clavien-Dindo classification.

RESULTS

 A total of 239 studies dealing with 19 types of procedures and outcomes in 929,157 patients were analyzed. We identified 26 randomized controlled trials (10.8%) and 213 comparative studies (89.2%). The most frequently reported advantage of laparoscopy was shorter hospital stay in 60.4% of studies. Longer operative time was the most frequently reported disadvantage of laparoscopy in 52.7% of studies. Clavien-Dindo grade I to III complications (mild-moderate) were less frequently identified in laparoscopic compared to open procedures (80.3% of studies). Grade-IV complications (severe) were less frequently reported after laparoscopic versus open appendectomy for perforated appendicitis and more frequently after laparoscopic Kasai's portoenterostomy. We identified a decreased frequency of reporting on advantages after laparoscopy and increased reporting on disadvantages for all surgery types over the decades.

CONCLUSION

 Laparoscopic compared with open pediatric surgery seems to be beneficial in most types of procedures. The number of randomized controlled trials (RCTs) remains limited. However, the number of reports on disadvantages increased during the past decades.

Technical aspects of paediatric robotic pancreatic enucleation based on a case of an insulinoma

BACKGROUND

Insulinomas are rare insulin-producing pancreatic neuroendocrine tumours leading to severe episodes of hypoglycaemia. Surgery is the predominant curative therapy.

METHODS

We report here the first paediatric case of an insulinoma of the pancreatic body resected completely robotically under ultrasound guidance in a 10-year-old male with multiple endocrine neoplasia type 1. The port set-up was adapted for the narrowed dimensions of the paediatric peritoneal space. We comment on technical key steps for the organ-preserving procedure that was performed in close proximity to critical anatomic structures, with supporting video. Preoperative diagnostics, including endoscopic ultrasound, to determine surgical management are highlighted.

RESULTS

Following an uneventful post-operative course, the boy was discharged on day 11 with normalised glucose-metabolism. A pseudocyst developing after 4 weeks was treated with endoscopic stenting.

CONCLUSIONS

The applicability of a robotic surgical system in limited space conditions such as found in the paediatric abdominal cavity is demonstrated here for pancreatic surgery.

New therapies for patients with multiple endocrine neoplasia type 1

In 1953, for the first time, Paul Wermer described a family presenting endocrine gland neoplasms over several generations. The transmission was autosomal dominant and the penetrance was high. Forty years later in 1997, the multiple endocrine neoplasia type 1 (MEN1) gene was sequenced, thus enabling diagnosis and early optimal treatment. Patients carrying the MEN1 gene present endocrine but also non-endocrine tumors. Parathyroid, pancreatic and pituitary impairment are the three main types of endocrine involvement. The present article details therapeutic management of hyperparathyroidism, neuroendocrine pancreatic tumors and pituitary adenomas in patients carrying the MEN1 gene. Significant therapeutic progress has in fact been made in the last few years. As concerns the parathyroid glands, screening of family members and regular monitoring of affected subjects now raise the question of early management of parathyroid lesions and optimal timing of parathyroid surgery. As concerns the duodenum-pancreas, proton-pump inhibitors are able to control gastrin-secreting syndrome, reducing mortality in MEN1 patients. Mortality in MEN1 patients is no longer mainly secondary to uncontrolled hormonal secretion but to metastatic (mainly pancreatic) disease progression. Tumor risk requires regular monitoring of morphological assessment, leading to iterative pancreatic surgery in a large number of patients. Finally, pituitary adenomas in MEN1 patients are traditionally described as aggressive, invasive and resistant to medical treatment. However, regular pituitary screening showed them to be in fact infra-centimetric and non-secreting in the majority of patients. Consequently, it is necessary to regularly monitor MEN1 patients, with regular clinical, biological and morphological work-up. Several studies showed that this regular monitoring impairs quality of life. Building a relationship of trust between patients and care provider is therefore essential. It enables the patient to be referred for psychological or psychiatric care in difficult times, providing long-term support and preventing any breakdown in continuity of care.

Updated Meta-analysis of Minimally Invasive Versus Open Surgery for Pancreatic Neuroendocrine Neoplasms

OBJECTIVES

The aim of this study was to compare the short-term and long-term outcomes of minimally invasive surgery (MIS) with those of open pancreas surgery (OPS) for the treatment of pancreatic neuroendocrine neoplasms (pNENs).

METHODS

Studies reporting the effects of MIS and OPS for pNENs, published on PubMed, Embase, and Cochrane Library before May 2020 were reviewed.

RESULTS

Seventeen cohort studies with a total of 1853 patients were eligible for analysis, including 655 patients in the MIS group and 1198 patients in the OPS group. The estimated blood loss, postoperative hospitalization time, overall complications, severe complications, spleen preservation, mortality, and recurrence in the MIS group were lower than those in the OPS group. The R0 rate, 3-year overall survival (OS), and 5-year OS in the MIS group were higher than those in the OPS group. There were no significant differences in operative time, postoperative pancreatic fistula, clinical postoperative pancreatic fistula, postoperative bleeding, reoperation, readmission, and 1-year OS.

CONCLUSIONS

Minimally invasive surgery can reach lower recurrence rate, higher long-term survival rate, and better outcomes in terms of estimated blood loss, postoperative hospitalization time, R0 rate, mortality, overall complications, and severe complications for pNENs. More high quality studies need to be conducted for further verification.

Multiple Endocrine Neoplasia Type 1 and the Pancreas: Diagnosis and Treatment of Functioning and Non-Functioning Pancreatic and Duodenal Neuroendocrine Neoplasia within the MEN1 Syndrome - An International Consensus Statement

The better understanding of the biological behavior of multiple endocrine neoplasia type 1 (MEN1) organ manifestations and the increase in clinical experience warrant a revision of previously published guidelines. Duodenopancreatic neuroendocrine neoplasias (DP-NENs) are still the second most common manifestation in MEN1 and, besides NENs of the thymus, remain a leading cause of death. DP-NENs are thus of main interest in the effort to reevaluate recommendations for their diagnosis and treatment. Especially over the last 2 years, more clinical experience has documented the follow-up of treated and untreated (natural-course) DP-NENs. It was the aim of the international consortium of experts in endocrinology, genetics, radiology, surgery, gastroenterology, and oncology to systematically review the literature and to present a consensus statement based on the highest levels of evidence. Reviewing the literature published over the past decade, the focus was on the diagnosis of F- and NF-DP-NENs within the MEN1 syndrome in an effort to further standardize and improve treatment and follow-up, as well as to establish a "logbook" for the diagnosis and treatment of DP-NENs. This shall help further reduce complications and improve long-term treatment results in these rare tumors. The following international consensus statement builds upon the previously published guidelines of 2001 and 2012 and attempts to supplement the recommendations issued by various national and international societies.

Surgery for multiple endocrine neoplasia type 1-related insulinoma: long-term outcomes in a large international cohort

Background

Insulinomas are found in 10–15 per cent of patients with multiple endocrine neoplasia type 1 (MEN1) and lead to life‐threatening hypoglycaemia. Surgical outcome and the optimal surgical strategy for MEN1‐related insulinoma are unknown.

Methods

Patients with MEN1‐related insulinomas were identified in 46 centres in Europe and North America between 1990 and 2016. Insulinomas were considered localized if the lesion was in the pancreatic head or body/tail. Patients with pancreatic neuroendocrine tumours throughout the pancreas were suspected of having multifocal insulinoma. The primary outcome was postoperative hypoglycaemia, defined as persistent hypoglycaemia, or recurrent hypoglycaemia caused by a new insulinoma or insulin‐producing liver metastases. Hypoglycaemia‐free survival was estimated by the Kaplan–Meier method.

Results

Ninety‐six patients underwent resection for MEN1‐related insulinoma. Sixty‐three and 33 patients had localized and multifocal insulinomas respectively. After a median follow‐up of 8 (range 1–22) years, one patient (1 per cent) had persistent disease and six (6 per cent) had developed recurrent disease, of whom four had a new insulinoma. The 10‐year hypoglycaemia‐free survival rate was 91 (95 per cent c.i. 80 to 96) per cent. Of those with localized disease, 46 patients underwent pancreatic resection and 17 enucleation. One of these patients had persistent disease and one developed recurrent insulinoma. Among patients with multifocal disease, three developed new insulinomas and two developed insulin‐producing liver metastases.

Conclusion

Surgery for MEN1‐related insulinoma is more successful than previously thought.

Outcomes after distal pancreatectomy for neuroendocrine neoplasms: a retrospective comparison between minimally invasive and open approach using propensity score weighting

BACKGROUND

Pancreatic neuroendocrine neoplasms (PanNEN) are ideal entities for minimally invasive surgery. The advantage of the laparoscopic approach in terms of complications, length of stay (LOS) and cosmetic results has been previously demonstrated. However, scarce data are available on long-term oncological outcomes. Aim of this study was to compare short-term postoperative outcomes, pathological findings and long-term oncological results of minimally invasive distal pancreatectomy (MIDP) and open distal pancreatectomy (ODP) for PanNEN.

METHODS

Patients who underwent ODP or MIDP for nonfunctioning PanNEN (NF-PanNEN) were retrospectively analyzed. Inverse probability of treatment weighting using propensity score was performed to compare the outcomes of MIDP and ODP.

RESULTS

Overall, 124 patients were included in the study: 84 underwent OPD, whereas 40 were submitted to MIDP. The rate of high-grade postoperative complications was significantly lower in the MIDP group (p = 0.005, grade of complication with highest estimated probability 0 vs 2) and the postoperative LOS was significantly shorter after MIDP (p < 0.001, estimated days 8 versus 10). The number of examined lymph nodes (ELN) in the ODP group was significantly higher (p = 0.0036, estimated number of ELN 13 vs 10). Similar disease-free survival and overall survival were reported for the two groups (p = 0.234 and p = 0.666, respectively).

CONCLUSIONS

Although MIDP for PanNEN seems to be associated with a lower number of ELN, long-term survival is not influenced by the type of surgical approach. MIDP is advantageous in terms of postoperative complications and LOS, but prospective studies are needed to confirm the overall oncological quality of resection in this group of neoplasms.

Contemporary surgical management of the Zollinger-Ellison syndrome in multiple endocrine neoplasia type 1

About 30% of patients with MEN1 develop a Zollinger-Ellison syndrome. Meanwhile it is well established that the causative gastrinomas are almost exclusively localized in the duodenum and not in the pancreas, MEN1 gastrinomas occur multicentric and are associated with hyperplastic gastrin cell lesions and tiny gastrin-producing micro tumors in contrast to sporadic duodenal gastrinomas. Regardless of the high prevalence of early lymphatic metastases, the survival is generally good with an aggressive course of disease in only about 20% of patients. Symptoms can be controlled medically. The indication, timing, type, and extent of surgery are highly controversial and are discussed in detail in this article by a thorough and critical review of literature. More radical procedures, like partial pancreaticoduodenectomy, are weighed against less aggressive local excision of gastrinomas and the pros and cons of both approaches are discussed in terms of long-term morbidity, biochemical cure, and survival.

Chemoprevention with Somatuline© Delays the Progression of Pancreatic Neuroendocrine Neoplasms in a Mouse Model of Multiple Endocrine Neoplasia Type 1 (MEN1)

OBJECTIVE

Long-acting synthetic somatostatin analogues (SSA) are an essential part of the treatment of neuroendocrine neoplasms. We evaluated the chemopreventive effects of a long-acting somatostatin analogue on the development of pancreatic neuroendocrine neoplasms (pNENs) in a genetically engineered MEN1 knockout mouse model.

MATERIALS AND METHODS

Heterozygote MEN1 knockout mice were injected every 28 days subcutaneously with the somatostatin analogue lanreotide (Somatuline Autogel©; Ipsen Pharma) or a placebo starting at day 35 after birth. Mice were euthanized after 6, 9, 12, 15 and 18 months, and the size and number of pNENs were measured due histological analysis and compared to the placebo group.

RESULTS

The median tumor size of pNENs was statistically significantly smaller after 9 (control group vs. SSA group; 706.476 µm² vs. 195.271 µm²; p = 0.0012), 12 (placebo group vs. SSA group 822.022 vs. 255.482; p ≤ 0.001), 15 (placebo group vs. SSA group 1192.568 vs. 273.533; p ≤ 0.001) and after 18 months (placebo group vs. SSA group 1328.299 vs. 864.587; p ≤ 0.001) in the SSA group. Comparing the amount of tumors in both groups, a significant reduction was achieved in treated Men1^(+/-) mice (41%, p = 0.002). Immunostaining showed, however, no significant difference in the expression of the apoptosis marker caspase-3, but a significant difference in Ki67 index as a marker for tumor cell proliferation (p ≤ 0.005).

CONCLUSION

Long-acting somatostatin analogues may be an effective chemopreventive approach to delay the progression of MEN1-associated pNENs. After our preclinical results, we would recommend to evaluate the effects of long-acting SSA in a prospective clinical trial.

Patient characteristics and clinical outcomes following initial surgical intervention for MEN1 associated pancreatic neuroendocrine tumours: A systematic review and exploratory meta-analysis of the literature

BACKGROUND

This systematic review aimed to define the outcomes of different pancreatic resection procedures for multiple endocrine neoplasia type 1 (MEN1) associated pancreatic neuroendocrine neoplasms (pNENs).

METHODS

A search of PubMed, MEDLINE and SCOPUS databases were performed in accordance with PRISMA guidelines.

RESULTS

Twenty-seven studies including 533 patients undergoing initial pancreatic resection for MEN1 associated pNENs were included in this systematic review. Three hundred and sixty-six (68.7%) distal pancreatectomies (DP), 120 (22.5%) sole enucleations (SE) and 47 (8.8%) pancreaticoduodenectomies (PD) were identified. SE was associated with a higher rate of recurrence than DP (25/67, 37% vs 40/190, 21% respectively, P = 0.008) but a lower rate of endocrine insufficiency than PD (1/20, 5% vs 8/21, 38% respectively, P = 0.010). A meta-analysis of major pancreatic resections (PD or DP) vs SE in 15 studies showed that SE is associated with an increased rate of recurrence (Major resection 42/184, 23% vs SE 20/53, 38% RR 0.65 CI 0.43-0.96 P = 0.032) but reduced rate of postoperative endocrine insufficiency (Resection 37/93, 40% vs SE 0/24, 0% RR 7.37 CI 1.57-34.64 P = 0.008). Similarly, insulinomas and functional pNENs overall had lower rates of recurrence and reoperation with major resection. There was no difference in the reoperation rates or survival outcomes after SE compared with major pancreatic resections at follow-up (pooled overall mean duration: 85 months).

CONCLUSION

Major pancreatic resections for MEN1 associated pNENs have a lower risk of recurrence and a higher risk of postoperative endocrine insufficiency when compared to sole enucleation, but a similar rate of reoperation and survival.

Intertumor heterogeneity in 60 pancreatic neuroendocrine tumors associated with multiple endocrine neoplasia type 1

BACKGROUND

Patients with multiple endocrine neoplasia type 1 (MEN-1) develop multiple pancreatic neuroendocrine neoplasias (PNENs). Size at diagnosis and growth during follow-up are crucial parameters. According to the WHO 2017, grading is another important parameter. The impact of grading compared to size (WHO 2000) on the clinical course needs to be evaluated.

METHODS

Sixty PNENs of six patients with MEN-1 were retrospectively evaluated.

RESULTS

Fifty-one tumors with a diameter of < 20 mm were graded as G1. Two of 9 tumors with diameters of ≥20 mm were graded as G2. Tumor size of ≥20 mm correlated significantly with higher proliferation (p = 0.000617). Lymph node metastases were documented in two patients with a total of 19 tumors. In one patient, all 13 tumors (diameter: 0.4 to 100 mm) were classified as G1. However, metastases were documented in 9/29 lymph nodes. In the other patient, 5 tumors (3.5 to 20 mm) were classified as G1. The sixth tumor (30 mm) was classified as G2 (Ki-67: 8%). Metastases were revealed in 2/20 lymph nodes.

CONCLUSIONS

Tumor size of ≥20 mm seems to correlate with more aggressive MEN-1 related pancreatic disease, regardless of individual proliferation. Tumors ≥20 mm and tumors graded as G2 should be treated surgically regardless of their size.

Early and Late Complications After Surgery for MEN1-related Nonfunctioning Pancreatic Neuroendocrine Tumors

OBJECTIVE

To estimate short and long-term morbidity after pancreatic surgery for multiple endocrine neoplasia type 1 (MEN1)-related nonfunctioning pancreatic neuroendocrine tumors (NF-pNETs).

BACKGROUND

Fifty percent of the MEN1 patients harbor multiple NF-pNETs. The decision to proceed to NF-pNET surgery is a balance between the risk of disease progression versus the risk of surgery-related morbidity. Currently, there are insufficient data on the surgical complications after MEN1 NF-pNET surgery.

METHODS

MEN1 patients diagnosed with a NF-pNET who underwent surgery were selected from the DutchMEN1 study group database, including >90% of the Dutch MEN1 population. Early postoperative complications, new-onset diabetes mellitus, and exocrine pancreatic insufficiency were captured.

RESULTS

Sixty-one patients underwent NF-pNET surgery at 1 of the 8 Dutch academic centers. Patients were young (median age 41 years) with low American Society of Anesthesiologists scores. Median NF-pNET size on imaging was 22 mm (3-157). Thirty-three percent (19/58) of the patients developed major early-Clavien-Dindo grade III to IV-complications mainly consisting International Study Group of Pancreatic Surgery grade B/C pancreatic fistulas. Twenty-three percent of the patients (14/61) developed endocrine or exocrine pancreas insufficiency. The development of major early postoperative complications was independent of the NF-pNET tumor size. Twenty-one percent of the patients (12/58) developed multiple major early complications.

CONCLUSIONS

MEN1 NF-pNET surgery is associated with high rates of major short and long-term complications. Current findings should be taken into account in the shared decision-making process when MEN1 NF-pNET surgery is considered.

Preoperative Imaging Overestimates the Tumor Size in Pancreatic Neuroendocrine Neoplasms Associated with Multiple Endocrine Neoplasia Type 1

BACKGROUND

Radiological tumor size of non-functioning pancreatic neuroendocrine neoplasms (Nf-pNENs) associated with multiple endocrine neoplasia type 1 (MEN1) is a crucial parameter to indicate surgery. The aim of this study was to compare radiological size (RS) and pathologic size (PS) of MEN1 associated with pNENs.

METHODS

Prospectively collected data of MEN1 patients who underwent pancreatic resections for pNENs were retrospectively analyzed. RS was defined as the largest tumor diameter measured on endoscopic ultrasound (EUS), magnetic resonance imaging (MRI) or computed tomography (CT). PS was defined as the largest tumor diameter on pathological analysis. Student's t test and linear regression analysis were used to compare the median RS and PS. p < 0.05 was considered significant.

RESULTS

Forty-four patients with a median age of 37 (range 10-68) years underwent primary pancreatic resections for pNENs. Overall, the median RS (20 mm, range 3-100 mm) was significantly larger than the PS (13 mm, range 4-110 mm) (p = 0.001). In patients with pNENs < 20 mm (n = 27), the size difference (median RS 15 mm vs PS 12 mm) was also significant (p = 0.003). However, the only modality that significantly overestimated the PS was EUS (median RS 14 mm vs 11 mm; p = 0.0002). RS overestimated the PS in 21 patients (21 of 27 patients, 78%). Five of 11 patients (12%) with a Nf-pNEN and a RS > 20 mm had in reality a PS < 20 mm. MRI was the imaging technique that best correlated with PS in the total cohort (r = 0.8; p < 0.0001), whereas EUS was the best correlating imaging tool in pNENs < 20 mm (r = 0.5; p = 0.0001).

CONCLUSION

Preoperative imaging, especially EUS, frequently overestimates the size of MEN1-pNENs, especially those with a PS < 20 mm. This should be considered when indicating surgery in MEN1 patients with small Nf-pNENs.

Gastrinomas: Medical or Surgical Treatment

This article reviews the role of surgical and medical management in patients with Zollinger-Ellison syndrome (ZES) due to a gastrin-secreting neuroendocrine tumor (gastrinoma). It concentrates on the status at present but also briefly reviews the changes over time in treatment approaches. Generally, surgical and medical therapy are complementary today; however, in some cases, such as patients with ZES and multiple endocrine neoplasia type 1, the treatment approach remains controversial.

Minimally invasive distal pancreatectomy for PNETs: laparoscopic or robotic approach?

Background

The most effective and radical treatment for pancreatic neuroendocrine tumors (PNETs) is surgical resection. Minimally invasive surgery has been increasingly used in pancreatectomy. Initial results in robotic distal pancreatectomy (RDP) have been encouraging. Nonetheless, data comparing outcomes of RDP with those of laparoscopic distal pancreatectomy (LDP) in treating PNETs are rare. The aim of this study was to compare the safety and efficacy of RDP and LDP for PNETs.

Methods

From September 2010 to January 2017, operative parameters and perioperative outcomes in an initial experience with 43 consecutive patients undergoing RDP were collected and compared with those in 31 patients undergoing LDP.

Results

Patients undergoing RDP and LDP demonstrated equivalent age, sex, ASA score, tumor location and tumor size. Operating time, length of resected pancreas, postoperative length of hospital stay and rates of conversion to open, pancreatic fistula, transfusion and reoperation were not statistically different. Patients in the RDP group were associated with significantly higher overall (79.1 vs. 48.4 %, P = 0.006) and Kimura spleen preservation rates (72.1 vs. 16.1%, P < 0.001) and had reduced risk of excessive blood loss (50 vs. 200mL, P < 0.001). Oncological outcomes in this series were superior for the RDP group with more lymph node harvest for G2 and G3 PNETs (3.5 vs. 2, P = 0.034).

Conclusions

Both RDP and LDP are efficacious and safe methods in treating PNETs located in the body or tail of pancreas. Robotic approach offers advantages with less intraoperative blood loss, higher spleen preservation rate and more lymph node harvest. It may be sensible to choose RDP for patients who fit indications for scheduled spleen preservation.

Surgical resection of neuroendocrine tumors of the pancreas (pNETs) by minimally invasive surgery: the laparoscopic approach

Neuroendocrine tumors of the pancreas (pNETs) are a rare group of neoplasms that originate from the endocrine portion of the pancreas. Tumors that either secrete or do not secrete compounds, resulting in symptoms, can be classified as functioning and non-functioning pNETs, respectively. The prevalence of such tumors has recently increased due to the use of more sensitive imaging techniques, such as multidetector computed tomography, magnetic resonance imaging and endoscopic ultrasound. The biological behavior of pNETs varies widely from indolent, well-differentiated tumors to those that are far more aggressive. The most effective and radical treatment for pNETs is surgical resection. Over the last decade, minimally invasive surgery has been increasingly used in pancreatectomy, with laparoscopic pancreatic surgery (LPS) emerging as an alternative to open pancreatic surgery (OPS) in patients with pNETs. Non-comparative studies have shown that LPS is safe and effective. In well-selected groups of patients with pancreatic lesions, LPS was found to results in good perioperative outcomes, including reduced intraoperative blood loss, postoperative pain, time to recovery, and length of hospital stay. Despite the encouraging results of studies from highly specialized centers with extensive experience, no randomized trials to date have conclusively validated these findings. Indications for minimally invasive LPS for patients with pNETs remain unclear. This review presents the current state of LPS for pNETs.

Surgical resection of pancreatic neuroendocrine neoplasm by minimally invasive surgery-the robotic approach?

Over the past decade, there has been increasing adoption of minimally invasive pancreatic surgery world-wide and this has naturally expanded to the management of pancreatic neuroendocrine neoplasms (PNENs). More recently, robotic pancreatic surgery (RPS) was introduced to overcome the limitations during laparoscopic pancreatic surgery (LPS). Due to the relative rarity of PNEN and the novelty of minimally invasive pancreatic surgery in particular RPS today, the evidence for robotic surgery in PNENs remains extremely limited. Presently, the available evidence is limited to a few low level retrospective case-control studies. These studies suggest that RPS may be associated with a higher splenic preservation rates and lower open conversion rates compared to conventional laparoscopic surgery. Ideally a prospective randomized trial should be performed but this would be extremely challenging due to the rarity of PNEN, making it almost impossible to conduct a sufficiently powered trial.

Is there any role for minimally invasive surgery in NET?

Neuroendocrine tumors (NET) represent the variability of almost benign lesions either secreting hormones occurring as a single lesion up to malignant lesions with metastatic potential. Treatment of NET is usually performed by surgical resection. Due to the rarity of NET, surgical treatment is mainly based on the experience and recommendations of experts and less on the basis of prospective randomized studies. In addition, the development and establishment of new surgical procedures is made more difficult by their rarity. The development of laparoscopic-assisted surgery has significantly improved the treatment of many diseases. Due to the well-known advantages of laparoscopic surgery, this method has also been increasingly used to treat NET. However, due to limited comparative data, the assumed superiority of laparoscopic surgery in the area NET remains often unclear or not yet proven. This review focuses on the present usage of laparoscopic techniques in the area of NET. Relating to the current literature, this review presents the evidence of various laparoscopic procedures for treatment of adrenal, pancreatic and intestine NET as well as extraadrenal pheochromocytoma and neuroendocrine liver metastases. Further, this review focuses on recent new developments of minimally invasive surgery in the area of NET. Here, robotic-assisted surgery and single-port surgery are promising approaches.

Surgical Therapy of Sporadic Pancreatic Neuroendocrine Neoplasias G1/G2

Background

Pancreatic neuroendocrine neoplasias (pNENs) are uncommon but fascinating tumors with an annual incidence of 1 per 100,000 people. pNENs present either as functional tumors, causing specific hormonal syndromes like Zollinger-Ellison syndrome (ZES) or organic hyperinsulinism, or as non-functional pancreatic tumors (NF-pNENs). The natural history of pNENs is highly variable. 90% of all insulinomas or small NF- pNENs are readily curable by surgical resection. Most other functional and late detected NF-pNENs have a less favorable chance for cure.

Methods

A systematic review of the literature was performed to identify the current state of the art with regard to the key issues of surgery in pNEN G1/G2.

Results

This article provides a comprehensive review of the current literature addressing the current challenges in pNEN surgery.

Conclusion

Patients with completely resected tumors generally have a good prognosis, and an aggressive surgical approach combined with conservative treatment options in patients with advanced disease rarely provides cure but often results in long-term survival.

[Early endocrine neoplasia of the pancreas]

Pancreatic endocrine neoplasias (pNENs) are uncommon but fascinating tumors with a rising incidence. In accordance to its location, size and grading, the decision to operate the patient should always be made in an interdisciplinary approach. This article provides a comprehensive review of the current literature addressing the current challenges in pNEN surgery and shows that patients with completely resected small pNENs generally have an excellent prognosis, but also that surveillance may be a powerful tool.

Robotic enucleation of benign pancreatic tumors

Robot-assisted enucleation provides the dual benefits of a minimally-invasive technique and pancreatic parenchymal conservation to selected patients with functional pancreatic neuroendocrine tumors (F-pNETs) and serous cystadenomas. Insulinomas, the most common F-pNETs, are ideal candidates for enucleation when <2 cm given the 80% probability of being benign. Current evidence suggests enucleation for the following: benign, isolated lesions with a distance between tumor and main pancreatic duct ≥3 mm (no focal stricture or dilation), insulinomas, gastrinomas <2 cm, and nonfunctional pancreatic neuroendocrine tumors (NF-pNETs) <1-2 cm and low Ki67 mitotic index. Minimally-invasive enucleation is an imaging-dependent procedure that requires recognizable anatomic landmarks for successful completion, including tumor proximity to the pancreatic duct as well as localization relative to major structures such as the gastroduodenal artery, bile duct, and portal vein. Tumor localization often mandates intraoperative ultrasound aided by duplex studies of intratumoral blood flow and frozen section confirmation. Five patients have undergone robot-assisted enucleation at Beth Israel Deaconess Medical Center between January 2014 and January 2017 with median tumor diameter of 1.3 cm (0.9-1.7 cm) located in the pancreatic head [2] and tail [3]. Surgical indications included insulinoma [2] and NF-pNETs [3]. Median operative time was 204 min (range, 137-347 min) and estimated blood loss of 50 mL. There were no conversions to open or transfusions. Robotic enucleation is a safe and feasible technique that allows parenchymal conservation in a minimally-invasive setting, reducing operative time and length of stay with equivalent pathological outcomes compared to open surgery.

The future: diagnostic and imaging advances in MEN1 therapeutic approaches and management strategies

Prospective randomized data are lacking, but current clinical expert guidelines recommend annual screening examinations, including laboratory assessments and various imaging modalities (e.g. CT, MRI, scintigraphy and EUS) for patients with multiple endocrine neoplasia type 1 (MEN1). Routine screening is proposed to detect and localize neuroendocrine manifestations as early as possible. The goal is timely intervention to improve quality of life and to increase life expectancy by preventing the development of life-threatening hormonal syndromes and/or metastatic disease. In recent years, some studies compared different and new imaging methods regarding their sensitivity and utility in MEN1 patients. This present article reviews the proposed diagnostic tools for MEN1 screening as well as potential future perspectives.

The future: surgical advances in MEN1 therapeutic approaches and management strategies

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary autosomal dominant disorder associated with numerous neuroendocrine tumors (NETs). Recent advances in the management of MEN1 have led to a decrease in mortality due to excess hormones; however, they have also led to an increase in mortality from malignancy, particularly NETs. The main challenges are to localize these tumors, to select those that need therapy because of the risk of aggressive behavior and to select the appropriate therapy associated with minimal morbidity. This must be applied to a hereditary disease with a high risk of recurrence. The overall aim of management in MEN1 is to ensure that the patient remains disease- and symptom-free for as long as possible and maintains a good quality of life. Herein, we review the changes that occurred in the last 20 years in the surgical management of MEN1-associated functional and non-functional pancreatico-duodenal NETs and thymic and bronchial NETs.

The treatment of hyperinsulinemic hypoglycaemia in adults: an update

BACKGROUND

Treatment of hyperinsulinemic hypoglycaemia (HH) is challenging due to the rarity of this condition and the difficulty of differential diagnosis. The aim of this article is to give an overview of the recent literature on the management of adult HH.

METHODS

A search for reviews, original articles, original case reports between 1995 and 2016 in PubMed using the following keywords: hyperinsulinemic hypoglycaemia, insulinoma, nesidioblastosis, gastric bypass, autoimmune hypoglycaemia, hyperinsulinism, treatment was performed.

RESULTS

One hundred and forty articles were selected and analysed focusing on the most recent treatments of HH.

CONCLUSIONS

New approaches to treatment of HH are available including mini-invasive surgical techniques and alternative local-regional ablative therapy for benign insulinoma and everolimus for malignant insulinoma. A correct differential diagnosis is of paramount importance to avoid unnecessary surgical operations and to implement the appropriate treatment mainly in the uncommon forms of HH, such as nesidioblastosis and autoimmune hypoglycaemia.