Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors

The incidence of pancreatic neuroendocrine tumors (PNETs) is on the rise primarily due to the increasing use of cross-sectional imaging. Most of these incidentally detected lesions are non-functional PNETs with a small proportion of lesions being hormone-secreting, functional neoplasms. With recent advances in surgical approaches and systemic therapies, the management of PNETs have undergone a paradigm shift towards a more individualized approach. In this manuscript, we review the histologic classification and diagnostic approaches to both functional and non-functional PNETs. Additionally, we detail multidisciplinary approaches and surgical considerations tailored to the tumor's biology, location, and functionality based on recent evidence. We also discuss the complexities of metastatic disease, exploring liver-directed therapies and the evolving landscape of minimally invasive surgical techniques.

Thyroidectomy Outcomes in Obese Patients

INTRODUCTION

Obese patients often have higher complication rates after elective general surgeries; however, few studies have examined the outcomes after thyroidectomy. This study examines whether increased body mass index (BMI) is associated with poor postoperative outcomes after thyroid surgery.

METHODS

A retrospective review of patients who underwent thyroidectomy from 2015 to 2018 was performed. Demographics, comorbidities, pathology, and extent of resection (total versus hemithyroidectomy) were examined. Patients were classified into BMI groups according to the WHO definitions, and the incidence of surgical outcomes was determined in each group. Surgical outcomes of interest included readmission rates (RRs), length of stay, average operating room time, return to the operating room, hypocalcemia, postop infections, hematomas, and recurrent laryngeal nerve injury. Between-subjects statistics including independent samples t-test, ANOVA, and chi-square analyses were performed.

RESULTS

There were n = 465 patients included with a mean BMI 32.35 (standard deviation = 8.55) and median BMI 30.78 (Q1 = 26.26, Q3 = 36.73). There were no differences between BMI groups in age, gender, smoking, heart disease. There was a positive association between increased BMI and postoperative infection (P < 0.001), pneumonia (P = 0.018), and surgical site infection (P = 0.04), which were highest for BMI > 40. Increased BMI was associated with a higher 30-d RR (P = 0.008), particularly for BMI >40 versus BMI <40 (6.2% versus 1.05%; P = 0.003). There were no significant differences between surgical outcomes for patients with increased BMI who underwent total thyroidectomy or hemithyroidectomy.

CONCLUSIONS

Excellent postoperative outcomes were observed in all BMI categories. Higher postoperative infection and 30-d RRs were observed in the morbidly obese. Contrary to previous studies, operating room times were similar regardless of BMI.

A >50% Intraoperative Parathyroid Hormone Decrease Into Normal Reference Range Predicts Complete Excision of Malignancy in Patients With Parathyroid Carcinoma

INTRODUCTION

The mainstay of successful treatment for parathyroid carcinoma remains complete surgical excision. Although intraoperative parathyroid hormone (ioPTH) monitoring is a useful adjunct during parathyroidectomy for benign primary hyperparathyroidism, its utility for parathyroid carcinoma remains unclear.

METHODS

A retrospective review of 796 patients who underwent parathyroidectomy with ioPTH monitoring for primary hyperparathyroidism revealed 13 patients with parathyroid carcinoma on final pathology from two academic institutions. A systematic review yielded 5 additional parathyroid carcinoma patients. Complete excision of malignancy, or operative success (eucalcemia ≥6 mo. after parathyroidectomy); operative failure (persistent hypercalcemia <6 mo. after parathyroidectomy); and perioperative complications were evaluated. Comparison of the >50% ioPTH decrease alone to >50% ioPTH decrease into normal reference range was analyzed using Chi-squared, Kolmogorov-Smirnov, Kruskal-Wallis tests.

RESULTS

All 18 parathyroid carcinoma patients achieved a >50% ioPTH decrease, and 14 patients also had a final ioPTH level decrease into normal reference range. 93% of patients who met normal parathyroid hormone reference range had operative success, whereas only two of the four (50%) patients with parathyroid carcinoma with a >50% ioPTH decrease alone demonstrated operative success.

CONCLUSIONS

Parathyroidectomy guided by a >50% ioPTH decrease into normal reference range may better predict complete excision of malignant tissue in patients with parathyroid carcinoma compared to >50% ioPTH decrease alone. IoPTH monitoring should be used in conjunction with clinical judgment and complete en bloc resection for optimal treatment and success.

Operative success is achieved regardless of ioPTH criterion used during focused parathyroidectomy for sporadic primary hyperparathyroidism

BACKGROUND

Focused parathyroidectomy (F-PTX) guided by intraoperative parathormone (ioPTH) monitoring may result in higher operative failure rates from missed multiglandular disease (MGD) in patients with sporadic primary hyperparathyroidism (spHPT) when ioPTH levels do not reach normal range.

METHODS

A retrospective review included 690 patients with spHPT who underwent F-PTX and ioPTH monitoring were divided into 2 groups: >50% ioPTH decrease to normal range, and >50% ioPTH decrease to above normal range. Operative success, recurrence, bilateral/unilateral neck exploration (BNE/UNE), MGD were evaluated.

RESULTS

533 patients demonstrated >50% ioPTH decrease to normal range, and 157 patients >50% ioPTH decrease to above normal range. There were no differences in operative success 99% vs. 97%, recurrence 2.5% vs. 5%, BNE 12% vs. 11%, UNE 4% vs. 5%, or MGD 4% vs. 4%, (p > 0.05) with 46 months mean follow-up.

CONCLUSIONS

There were no differences in operative success, failure, BNE, UNE or MGD regardless of ioPTH criterion used for F-PTX.

The Impact of Same-Day Discharge and Enhanced Recovery on Patient Quality of Life After Mastectomy with Implant Reconstruction

BACKGROUND

This study aimed to evaluate how enhanced recovery (ER) protocols and same-day discharge (SDD) influences patients' postoperative quality of life (QOL).

METHODS

Patients who underwent mastectomy with implant-based breast reconstruction from 2008 to 2020 were identified in a prospective database. The study assessed QOL with BREAST-Q and Was It Worth It? (WIWI) questionnaires. Responses were compared between the ER and pre-ER groups and between the SDD and hospital stay (HS) groups using one-way analysis of variance (ANOVA) and chi-square tests.

RESULTS

The inclusion criteria were met by 568 patients, with a 43% response rate, and 217 patients were included for analysis. Chest physical well-being was lower for the ER cohort, but postoperative breast satisfaction was higher. Psychosocial status, sexual well-being, and satisfaction with information given did not differ significantly between the ER group and the pre-ER or SDD group. In the compared groups, QOL did not differ significantly.

CONCLUSIONS

Enhanced recovery with SDD after mastectomy using implant-based reconstruction did not have an adverse impact on patient postoperative QOL.

Aesthetic Surgery Research Funding: Where Does It Come From and to Whom Does It Go?

BACKGROUND

Recent data show that aesthetic surgery research is lagging compared with reconstructive surgery: research funding and institutional disparities within aesthetic surgery are potential factors in this trend.

OBJECTIVES

The authors sought to determine if disparities exist in aesthetic surgery research based on funding sources or practice settings.

METHODS

The authors reviewed Aesthetic Surgery Journal articles from 2009 to 2019. Chi-square, t test, bivariate, and multivariate regression analyses were employed to evaluate research trends.

RESULTS

A total of 2262 publications were identified, with 318 funded articles meeting inclusion criteria. The majority of studies (294, 92%) received external funding, with 281 (88%) being supported solely by external funds. Externally funded studies were financed by private industry (194, 66%), foundations/societies (53, 18%), government grants (23, 8%), or a combination of agencies (24, 8%). The majority of funded studies were at academic institutions (266, 84%), followed by private practice (46, 14%) and private industry (6, 2%). Analysis of annual publications revealed a rising percentage of academic-based research, which correlated with decreasing research from private practice (r = -0.95, r2 = 0.89, P < 0.001). Compared with academic institutions, private practice relied more heavily on industry funding (55% vs 87%, respectively, P = 0.001), exhibiting lower rates of foundational/societal (20% vs 2%), governmental (9% vs 0%), combined (8% vs 7%), and internal department funding (8% vs 4%). Article citations and level of evidence were unaffected by funding source, agency, or practice setting.

CONCLUSIONS

Lack of diversity in research funding among private practice surgeons may explain the reported discrepancies that currently exist between aesthetic and reconstructive surgery research.

Infants at Risk for Autism Spectrum Disorder: Frequency, Quality, and Variety of Joint Attention Behaviors

Initiation of joint attention is a critical developmental function related to further social communicative development in infancy. Joint attention appears to be impaired very early in life for children with autism spectrum disorder (ASD), well before a formal diagnosis is established. To observe the early development of joint attention, we prospectively followed infant siblings at high risk for ASD (HR) and low-risk (LR) infants. Initiations of joint attention behaviors were coded with respect to frequency, quality, and variety from videos taken during the administration of the Autism Observation Schedule for Infants. Participants were further stratified based on the presence of ASD (n = 17) or language delay (n = 19) at 3 years of age. Our results revealed that initiations of joint attention are impaired from 12 months of age in both children with ASD and those with language delay, especially for use of gestures (i.e., showing and pointing). At 18 months, fewer initiations of joint attention in all three dimensions distinguished infants with ASD, compared to infants with language delay and HR and LR infants without a diagnosis. Beyond the definition of initiation of joint attention as an early sign for ASD, clinical implications of these results concern the importance of intervening on frequency, quality, and variety of joint attention as early as possible in infants at heightened risk for ASD.

Spondylodiscitis in end-stage renal disease: a systematic review

OBJECTIVEDiscitis and osteomyelitis are seen in end-stage renal disease (ESRD) patients due to repeated vascular access for hemodialysis and urinary tract infections leading to recurrent bacteremia. Discitis and osteomyelitis are underdiagnosed due to the nonspecific initial presentation of back pain. In this article, we review the literature for better understanding of the problem and the importance of early diagnosis by primary care physicians and nephrologists. In addition, we discuss the decision-making, follow-up, management, and neurological outcomes.METHODSA detailed PubMed search was performed using the following terms: "end stage renal disease (ESRD)" and "chronic renal failure (CRF)," combined with "spine infections," "spondylodiscitis," "discitis," and "osteomyelitis." Search results were limited to articles written in English, case reports, and case series from 1973 to 2012. Editorials, reviews, and commentaries were excluded. Only studies involving human patients were included. The authors also included 4 patients from their own patient population.RESULTSA total of 30 articles met the inclusion criteria. Including the 4 patients from the authors' patient population, 212 patients with spine infections and maintenance dialysis were identified. The patients' ages ranged from 38 to 78 years. The duration of dialysis ranged from a few days to 16 years. The time from onset of back pain to diagnosis ranged from 3 days to 6 months. The most common causative organism was Staphylococcus aureus, followed by Staphylococcus epidermidis and gram-negative bacteria. Most of the patients were treated with antibiotics alone (76.8%), although surgery was indicated when patients presented with neurological deficits (p < 0.011). Approximately one-quarter of the patients developed neurological deficits, with devastating consequences. Fever and neurological deficits at presentation, culture positive for methicillin-resistant S. aureus, and age > 65 years were highly correlated with mortality in our analysis.CONCLUSIONSSeveral risk factors lead to failure of antibiotics and progression of disease in patients with ESRD. Challenges to diagnosis include vague presenting symptoms, co-existing destructive spondyloarthropathy, poor immune response, chronic elevations of inflammatory markers, and recurrent bacteremia. Infectious processes are more likely to cause permanent neurological deficits than transient deficits. The authors recommend close observation and serial imaging of these patients for early signs of neurological deficits. Any signs of disease progression will require aggressive surgical debridement.

Central Neurocytoma: Rare Presentation in Fourth Ventricle and Review of Literature

Central neurocytomas are rare tumors, typically found in the third ventricle. We present the unusual case of a fourth ventricular central neurocytoma in a 70-year-old female presenting with imbalance and headaches, with an enhancing fourth ventricular mass on imaging. We examine the details of her clinical presentation, imaging characteristics, histopathologic analysis, and postoperative course. We performed a critical literature review of fourth ventricular central neurocytoma, identifying 6 previously reported cases. In contrast to our patient, the majority of these cases were in young males. The 2 females with fourth ventricular neurocytoma developed it at a much later age (mean 63.5 years) than their male counterparts (mean 22.8 years; P = 0.005). Despite being a rare cause for a fourth ventricular lesion, given the appropriate clinical context and radiographic findings, this should remain part of the differential diagnosis.

Insulin action and insulin secretion in polycystic ovary syndrome treated with ethinyl oestradiol/cyproterone acetate

Polycystic ovary syndrome (PCOS) is associated with abnormalities of insulin action and insulin secretion. Ethinyl oestradiol/cyproterone acetate is a common agent used to treat the symptoms of PCOS, but its effects on insulin action and insulin pulsatility have not been examined. We investigated the relationship between insulin action and insulin secretion in 11 patients with PCOS, at diagnosis and after 3 months of treatment with ethinyl oestradiol/cyproterone acetate, and in 13 controls. Insulin action was assessed using the euglycaemic hyperinsulinaemic clamp (2 mU/kg/min for 2 h). Insulin pulsatility was examined over 90 min by 2 min sampling. Short-term insulin pulses were identified using PULSAR. Treatment with ethinyl oestradiol/cyproterone acetate resulted in significant reductions in testosterone (3.3+/-0.7 vs. 1.9+/-0.2 nmol/l, p<0.05), free androgen index (10.2+/-0.7 vs. 1.2+/-0.2, p<0.05) and LH/FSH ratio (2.6+/-0.5 vs. 1.0+/-0.2, p<0.05). During hyperinsulinaemic clamps, the glucose infusion rate (GIR) required to maintain euglycaemia was lower in PCOS compared to controls (33.6+/-2.7 vs. 45.1+/-3.5 micromol/kg/min, p<0.05) but similar in PCOS before and after treatment (33.6+/-2.8 vs. 33.6+/-2.7 micromol/kg/min, p=0.9). Numbers of pulses identified in PCOS and controls were similar and unaltered by ethinyl oestradiol/cyproterone acetate. There was no correlation between GIR and frequency of insulin pulses in PCOS before or after treatment (r=0.2, p=0.6; post r=-0.5, p=0.1) unlike controls (r=-0.6, p=0.04). Despite considerable improvement in androgen profile, treatment with ethinyl oestradiol/cyproterone acetate did not alter insulin action in PCOS, and this insulin resistance does not appear to be determined by insulin pulse frequency.

Immunohistochemical evaluation of the post-translational processing of chromogranin A in human pituitary adenomas

Chromogranin A (CgA), pancreastatin (PST), intervening-peptide (IP) and WE-14 antisera were employed to investigate the proteolysis of CgA in 50 pituitary adenomas. All non-functioning (NF) pituitary tumours (n = 28) exhibited CgA immunoreactivity. PST, IP and WE-14 immunostaining was observed in 85%, 89% and 67%, respectively. CgA, PST and IP immunostaining were comparable in the majority of NF tumours, while less intense WE-14 immunoreactivity was detected in a subpopulation of NF tumour cells. Approximately half of the functioning pituitary tumours expressed CgA immunoreactivity. Six of nine ACTH-secreting tumours displayed CgA and IP immunostaining; four of these tumours displayed PST immunoreactivity. WE-14 immunoreactivity was detected in one corticotroph tumour. Three of six growth hormone (GH) secreting tumours displayed CgA immunostaining, two exhibited PST and IP, and one exhibited WE-14 immunoreactivity. Clusters of WE-14 immunopositive cells were detected in one GH tumour. One of seven prolactinomas exhibited weak CgA immunostaining, while weak IP and WE-14 immunostaining was detected in an additional tumour. No PST immunostaining was detected in prolactinomas. Therefore CgA is a valuable marker of NF pituitary tumours, however it is a more sporadic marker of functioning adenomas. In general, the cellular pattern and intensities of CgA, PST and IP immunoreactivity were comparable in the majority of pituitary adenomas. In contrast, WE-14 immunostaining was observed in a subpopulation of tumour cells. The pathophysiological significance of the proteolysis of CgA to generate bioactive peptides in both NF and functioning pituitary adenomas remains to be established.

Relationship between motility and oxygen consumption of sperm from the cauda epididymides of the rat

The oxygen consumption of rat sperm was low (2.7 microL O2 10(8) sperm(-1) h(-1)) in caudal epididymal semen (CES) when stimulation of motility was avoided. The addition of 1 microL of Krebs Ringer phosphate buffer (KRP) to 40 microL of CES (CES:KRP = 40:1) did not activate motility, but stimulated oxygen consumption 2-fold. Inclusion of 1-5 mM glucose, acetate, pyruvate or lactate in the KRP further stimulated respiration rate (up to 4.3-fold) without activating motility, but respiration was reduced when 2-deoxyglucose replaced energy substrates. Inclusion of dibutyryl cAMP (1 mM) activated sperm motility in all samples and stimulated oxygen consumption 2.9-fold. Dilution of CES at the ratio of CES:KRP = 40:1000 also activated sperm motility and stimulated respiration rate 2.9-fold. The combined effect of dibutyryl cAMP and glucose in stimulating respiration was greater than their individual effects. However, the response to cAMP or substrates was not altered by incubation in KRP containing either 0 or 0.5 mM Ca2+. It was concluded that the motility and metabolism of rat epididymal sperm are suppressed in vivo. Respiration can be stimulated by a small (1.025-fold) dilution and further stimulated by the inclusion of energy substrate, without activating motility. However, a larger dilution or inclusion of cAMP activated motility and simultaneously stimulated metabolism, with exogenous substrate being required to stimulate respiration to the maximum rate. This suggests that prior to activation, the rate of oxygen consumption and sperm motility are not coupled.

Insulin resistance and insulin pulsatility in essential hypertension

OBJECTIVE

Studies in normal humans and in patients with type 2 diabetes mellitus have demonstrated a close inverse relationship between peripheral insulin sensitivity and the frequency of short-term insulin secretory pulses in the systemic circulation. Our objective was to study this relationship in essential hypertension.

DESIGN

Study of insulin sensitivity and insulin pulse characteristics in hypertensive subjects and normotensive controls using well-established techniques.

METHODS

Twelve subjects with essential hypertension and 12 age- and sex-matched normotensive controls were recruited. Insulin action was measured using the glucose clamp technique combined with isotope dilution methodology. Insulin pulsatility in the peripheral circulation was assessed by sampling every 2 min for 90 min after an overnight fast Pulses were identified using the computer program Pulsar.

RESULTS

Insulin sensitivity index (glucose infusion rate/ serum insulin) was lower in the hypertensive patients (P= 0.01) and fasting insulin was increased (P= 0.008) compared to controls. The frequency and amplitude of insulin pulses were similar in the two groups. Insulin pulse frequency and insulin sensitivity were inversely related in the normotensive group (r= -0.68, P= 0.015), but not in the hypertensive group (r= -0.23, P= 0.48). Insulin clearance was reduced in the hypertensive group (P= 0.03), and was inversely related to insulin pulse frequency in the two groups combined (r = -0.51, P= 0.01).

CONCLUSIONS

Insulin action was not related to insulin pulse frequency in essential hypertension, in contrast to the situation in normal man.

Intracellular signal transduction mechanisms of rat epididymal spermatozoa and their relationship to motility and metabolism

The role of intracellular signal transduction mechanisms in regulating the motility and metabolism of rat spermatozoa in undiluted caudal epididymal fluid (CEF) was examined. Samples of CEF containing immotile spermatozoa were exposed to drugs and other agents that either stimulate signal transduction pathways or mimic the action of their second messengers. Under these conditions, sperm motility in 25-30 nl of CEF was stimulated by calcium ions (Ca2+), N2,2'-O-dibutyrylguanosine 3':5'-cyclic monophosphate (dibutyryl cGMP), cyclic adenosine 3':5'-monophosphate (cAMP), N6,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate (dibutyryl cAMP), 8-bromoadenosine 3':5'-cyclic monophosphate (8-bromo cAMP), caffeine, theophylline and bicarbonate ions (HCO3-). Other agents such as magnesium ions (Mg2+), veratridine, phospholipase C (PLC), ionophore A23187, 1,2-dioctenoyl-sn-glycerol (DAG), phorbol 12-myristate 13-acetate, phospholipase A2 (PLA2), arachidonic acid, and melittin did not significantly influence motility. In the presence of radiolabelled energy substrates, untreated (immotile) spermatozoa in samples of CEF utilised D-[U-14C]glucose and [1-14C]acetate as exogenous energy sources for oxidative metabolism. No detectable 14C-lactate was produced, and none of the drugs altered the rate of glycolytic or oxidative metabolism. The findings suggest that the motility of rat caudal epididymal spermatozoa is regulated by Ca2+ and the guanylate cyclase and adenylate cyclase pathways, but not through the PLC and PLA2 pathways. Also, their metabolism of exogenous substrate was uncoupled from the induction of motility, and their oxidative capacity exceeded the rate of flux of glucose-carbon through the glycolytic pathway.