Proctored preceptorship model for learning eTEP repair for inguinal hernia for general surgery residents

BACKGROUND

Enhanced-view total extra-peritoneal (eTEP) inguinal hernia repair is a technically demanding procedure with a steep learning curve.

AIM

Examine the feasibility and effectiveness of an instructor approach to teaching residents how to perform laparoscopic eTEP independently following a dedicated course of individual teaching.

METHODS

Prospective analysis of eTEP procedures performed by residents between March 2018 and September 2020. Six residents dispersed into three groups-Group A: two junior residents, Group B: two mid-level residents and Group C: two senior residents. All residents performed a unilateral IHR comprised of five core steps. Data reviewed for each procedure included the time of each step, total time and autonomy degree as assessment for every step: 1st degree-dependent (physical assistance), 2nd degree-partially dependent (vocal assistance) and 3rd degree-independent. Early and late procedures were divided at 50% of cases.

RESULTS

Participants performed 44 procedures (220 steps). Late procedures presented with a significant improvement in all degrees of autonomy (1st degree p = 0.002, 2nd degree p = 0.007 and 3rd degree p < 0.0001) and in every step (Step 1 p = 0.015, Step 2 p = 0.006, Step 3 p < 0.0001, Step 4 p < 0.0001, Step 5 p = 0.002). There was no significant difference in surgery duration between early and late procedures (p = 0.32). At early procedures, junior residents needed significantly higher rates of physical intervention (1st degree) compared to the senior residents (p = 0.004). Conversely, there was no significant difference in 2nd degree of autonomy (p = 0.46), 3rd degree (p = 0.06) and surgery duration (p = 0.16). The last three procedures performed by all participants had no significant difference between the seniority groups in autonomy (1st degree p = 0.1, 2nd degree p = 0.18 and 3rd degree p = 0.1).

CONCLUSION

Dedicated course with an individual instructor's approach is effective in achieving competence, autonomy and confidence in performing eTEP in a short time.

The Added Value of Technetium-99 m Sestamibi Scan in Patients with Primary Hyperparathyroidism and Positive Ultrasound

BACKGROUND

Neck ultrasound (US) and Technetium-99 m Sestamibi (MIBI) scan are the most commonly used imaging studies for preoperative localization of parathyroid adenomas. The aim of this study was to determine the added value of MIBI scan and its effect on the operative plan via a hypothetical model where a stepwise approach is conducted and MIBI is considered only after the ultrasound is evaluated.

METHODS

Patients who underwent parathyroidectomy for primary hyperparathyroidism (PHPT) between 2012 and 2019 at two tertiary centers were included. Data collected included demographic data, preoperative workup, operative findings and follow-up. The added value of MIBI scans was determined for patients with positive ultrasound.

RESULTS

A total of 513 patients with positive US result and a MIBI scan were included. If a stepwise approach was conducted then MIBI scan would not change the operative plan in 492 (95.9%). Among the remaining 21 patients, MIBI scan would correctly change the ultrasound-based operative plan in only 12 (2.3%) patients, while incorrectly change the plan in 9 (1.8%), resulting in unnecessary exploration of the contralateral side. In patients with sonographic appearance of a parathyroid gland larger than 1.2 cm, MIBI scan would correctly change the operative plan in only 1 of the 287 (0.35%) patients.

CONCLUSIONS

Our study suggests that the routine use of MIBI scans may have limited added value in patients with PHPT and a positive neck ultrasound, especially in those with adenoma size larger than 1.2 cm. Positive ultrasound alone may be sufficient for the preoperative localization of parathyroid disease.

Renal Proximal Tubule Cell Cannabinoid-1 Receptor Regulates Bone Remodeling and Mass via a Kidney-to-Bone Axis

The renal proximal tubule cells (RPTCs), well-known for maintaining glucose and mineral homeostasis, play a critical role in the regulation of kidney function and bone remodeling. Deterioration in RPTC function may therefore lead to the development of diabetic kidney disease (DKD) and osteoporosis. Previously, we have shown that the cannabinoid-1 receptor (CB1R) modulates both kidney function as well as bone remodeling and mass via its direct role in RPTCs and bone cells, respectively. Here we employed genetic and pharmacological approaches that target CB1R, and found that its specific nullification in RPTCs preserves bone mass and remodeling both under normo- and hyper-glycemic conditions, and that its chronic blockade prevents the development of diabetes-induced bone loss. These protective effects of negatively targeting CB1R specifically in RPTCs were associated with its ability to modulate erythropoietin (EPO) synthesis, a hormone known to affect bone mass and remodeling. Our findings highlight a novel molecular mechanism by which CB1R in RPTCs remotely regulates skeletal homeostasis via a kidney-to-bone axis that involves EPO.

Amplification of c-myc and c-erbB-2 proto-oncogenes in human solid tumors: frequency and clinical significance

Molecular probes for cellular proto-oncogenes have recently been extensively used in order to search for functional and structural alterations in tumor tissues. Variable, and sometimes contradictory, results have been obtained regarding the frequency and clinical significance of amplification of the c-myc and c-erbB-2 proto-oncogenes in different series of human solid tumors. We addressed this question by performing Southern blotting analysis on 131 primary adult solid tumors of various tissues and 5 metastases of unknown origin, using molecular probes for both genes. Amplification of c-myc was found in 5 of the primary tumors, and amplification of c-erbB-2 in 5 others. In 2 tumors of the latter group, the c-erbB-2 gene was also rearranged. The distribution of these 10 tumors with regard to clinical stage and course of the disease did not point to an association between the amplification events and specific stage or prognosis. We concluded that, in this series, the amplification of both proto-oncogenes was occasional and was not a prognostic marker.

Sporadic amplification of the HER2/neu protooncogene in adenocarcinomas of various tissues

The HER2/neu protooncogene was found to be amplified in 6 of 109 primary adenocarcinoma tumors. No HER2/neu amplification was found in 29 other primary nonadenocarcinomatous tumors. In two colon tumors, in addition to the amplification, DNA rearrangement of HER2/neu gene was also observed. The rearrangement was explored in detail in one tumor and it was shown to be confined to the 3' region of the gene. Moreover, this tumor expressed an aberrant HER2/neu polypeptide with a molecular weight of 190,000, which is larger by approximately 5,000 than the molecular weight of the normal HER2/neu protein. The aberrant HER2/neu protein was immunoprecipitated with site-specific antibodies against a synthetic peptide from the COOH-terminal end of the normal HER2/neu protein; it also displayed intrinsic protein tyrosine kinase activity leading to self-phosphorylation.