Apostolos Gaitanidis

Regenerated Nerve Defects with a Nerve Conduit Containing Dental Pulp Stem Cells in Pigs: An Immunohistochemical and Electrophysiological Evaluation

BACKGROUND Dental pulp stem cells (DPSCs) present an exciting new tool in the field of peripheral nerve regeneration due to their close embryonic origin. In this study, we examined their potential in pigs, using biodegradable collagen conduits filled with DPSCs. To our knowledge, this is the first time DPCSs are tested for peripheral nerve regeneration in such large animal model. MATERIALS AND METHODS The second lateral incisor was extracted from every animals lower jaw and stem cells were isolated and cultured. The collagen nerve conduits containing the DPSCs were subsequently transplanted into the transected fifth and sixth intercostal nerves, while the seventh intercostal nerve was used as a control and no stem cells were added on the respective collagen conduit. RESULTS A histological examination was performed on the 3rd and 6th postoperative months and showed the gradual development of neural tissue and immunohistochemical expression of neuron-specific enolase. An electrophysiological study was performed on the 6th postoperative month and showed similar potentials between the stem cell infusion region (5 ± 0.04 units) and their proximal stumps (5 ± 0.05 units) and slightly smaller potentials in the respective distal stumps (4 ± 0.045 units). CONCLUSION The nerves where DPSCs were injected exhibited morphological and functional recovery, in contrast to the control nerves where no recovery was detected; thus, there is a first evidence of the therapeutic potential of DPSCs in peripheral nerve regeneration.

Trends in incidence and associated risk factors of suicide mortality among breast cancer patients

Breast cancer patients are associated with an increased risk for committing suicide. The purpose of this study was to study the trends in the incidence of suicide mortality and identify pertinent risk factors among patients with breast cancer.

Refusal of Cancer-Directed Surgery by Breast Cancer Patients: Risk Factors and Survival Outcomes

&NA; A retrospective search of the Surveillance Epidemiology and End Results database was performed to identify risk factors and eventual outcomes of patients refusing breast cancer–directed surgery. An incidence of 0.64% and an increasing trend were found. Age, ethnicity, marital status, stage, and lack of insurance were independent risk factors. Refusing surgery was associated with 2.42 times higher risk of mortality. Background: It has been reported that some patients with breast cancer may refuse cancer‐directed surgery, but the incidence in the United States is not currently known. The purpose of this study was to identify the incidence, trends, risk factors, and eventual survival outcomes associated with refusal of recommended breast cancer–directed surgery. Patients: A retrospective review of the Surveillance Epidemiology and End Results (SEER) database between 2004 and 2013 was performed. Patients who underwent cancer‐directed surgery were compared with patients in whom cancer‐directed surgery was refused, even though it was recommended. Results: Of 531,700 patients identified, 3389 (0.64%) refused surgery. An increasing trend was observed from 2004 to 2013 (P = .009). Older age (50‐69: odds ratio [OR] 4.96; 95% confidence interval, 1.23‐19.96; P = .024, ≥ 70 years: OR 17.27; 95% CI, 4.29‐69.54; P < .001), ethnicity (P < .001), marital status (single: OR 2.28; 95% CI, 1.98‐2.62; P < .001, separated/divorced/widowed: OR 2.26; 95% CI, 2.01‐2.53; P < .001), higher stage (II: OR 2.05; 95% CI, 1.83‐2.3; P < .001, III: OR 2.2; 95% CI, 1.87‐2.6; P < .001, IV: OR 13.3; 95% CI, 11.67‐15.16; P < .001), and lack of medical insurance (OR 2.11; 95% CI, 1.59‐2.8; P < .001) were identified as risk factors associated with refusal of surgery. Survival analysis showed a 2.42 higher risk of mortality in these patients. Conclusion: There has been an increasing rate of patients refusing recommended surgery, which significantly affects survival. Age, ethnicity, marital status, disease stage, and lack of insurance are associated with higher risk of refusal of surgery.

What to consider when designing a laparoscopic colorectal training curriculum: a review of the literature

Multiple studies have demonstrated the benefits of laparoscopic colorectal surgery (LCS), but in several countries it has still not been widely adopted. LCS training is associated with several challenges, such as patient safety concerns and a steep learning curve. Current evidence may facilitate designing of efficient training curricula to overcome these challenges. Basic training with virtual reality simulators has witnessed meteoric advances and may be essential during the early parts of the learning curve. Cadaveric and animal model training still constitutes an indispensable training tool, due to a higher degree of difficulty and greater resemblance to real operative conditions. In addition, recent evidence favors the use of novel training paradigms, such as proficiency-based training, case selection and modular training. This review summarizes the recent advances in LCS training and provides the evidence for designing an efficient training curriculum to overcome the challenges of LCS training.

Incidence and predictors of synchronous liver metastases in patients with gastrointestinal stromal tumors (GISTs)

BACKGROUND The liver is the most common metastatic site in patients with gastrointestinal stromal tumors (GISTs). The purpose of this study is to identify the incidence and predictive factors associated with synchronous liver metastases among patients with GISTs. METHODS A retrospective review of the Surveillance Epidemiology and End Results (SEER) database was performed. RESULTS Overall, 2757 patients were identified, of which 276 (10%) had synchronous liver metastases. The two-year survival of patients with synchronous liver metastases was 31.9% overall and 37.1% after undergoing surgery with curative intent. Primary tumor size >5 cm (5-10 cm: OR 2.97, 95% CI: 1.03-8.55, p = 0.044, >10 cm: OR 5.59, 95% CI: 1.95-16.07, p = 0.001), presence of nodal metastases (OR 4.09, 95% CI: 2.01-8.33, p < 0.001) and mitotic count >5/50 HPF (OR 1.58, 95% CI: 1.01-2.47, p = 0.044) were associated with the presence of liver metastases. CONCLUSIONS One out of ten patients with GISTs presents with hepatic metastases. Primary tumor size >5 cm, presence of nodal metastases and mitotic count >5/50 HPF are associated with a higher risk of synchronous hepatic metastases.

Measures for risk factor stratification to prevent suicide mortality in breast cancer patients: A reply

We thank Foong and colleagues for their interest in our study and their interesting comments. In our discussion, we mentioned and encouraged the use of validated ways to screen for suicidal ideation, such as the Beck Depression Inventory, a self‐report rating tool. In our study, we identified several risk factors associated with an increased risk for committing suicide among those parameters that were available to us, but as we stated in our discussion, the use of those risk factors is ancillary to the use of the aforementioned validated tools and does not replace them. The limitations regarding the lack of information concerning any underlying issues of depression, anxiety, etc have been acknowledged in our limitations and are to be expected with any large‐scale population study.

Incidence and management of postoperative hyperglycemia in patients undergoing insulinoma resection

PurposeIt has been proposed that rebound hyperglycemia after resection of insulinoma indicates a biochemical cure. However, there is scant objective data in the literature on the rate and need for intervention in hyperglycemia in patients undergoing resection of insulinoma. The goal of our study was to evaluate the rate of postoperative hyperglycemia, any predisposing factors, and the need for intervention in a prospective cohort study of all patients undergoing routine glucose monitoring.MethodsA retrospective analysis of 33 patients who had an insulinoma resected and who underwent routine postoperative monitoring of blood glucose (every hour for the first six hours then every four hours for the first 24 h) was performed. Hyperglycemia was defined as glucose greater than 180 mg/dL (10 mmol/l).ResultsTwelve patients (36%) developed hyperglycemia within 24 h (range 1–16 h). In patients with hyperglycemia, the mean maximum plasma glucose level was 221.5 mg/dL (range 97–325 mg/dL) (12.3 mmol/l), and four (33%) patients were treated with insulin. There was no significant difference in age, gender, body mass index (BMI), tumor size, biochemical profile, or surgical approach and extent of pancreatectomy between patients who developed hyperglycemia and those who did not. Pre-excision and post-excision intraoperative insulin levels were evaluated in 14 of 33 patients. The percentage decrease of the intraoperative insulin levels was not significantly different between patients who developed hyperglycemia and those who did not. All patients with postoperative hyperglycemia had normalization of their glucose levels, and none were discharged on anti-hyperglycemic agents.ConclusionsHyperglycemia is common after insulinoma resection, and a subset of patients require transient treatment with insulin.

ASO Author Reflections: Systemic Inflammatory Markers in Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are rare tumors, exhibiting highly variable biological behavior, ranging from indolent to aggressive. Predicting the biological behavior of PNETs is difficult. Prognostic factors currently utilized to predict tumor progression, recurrence, or survival include tumor grade, presence of lymph node metastasis, and perineural invasion. In the majority of cases, these factors are available only after histologic examination. Therefore, novel biomarkers are needed to improve prognostic assessment in patients with PNETs to optimize management and treatment. The prognostic value of several markers of systemic inflammatory response has been suggested by several studies for different types of cancer, including neuroendocrine tumors. The aim of this study is to examine the potential prognostic role of markers of systemic inflammatory response in patients with PNETs.