Venous Thromboembolism Chemoprophylaxis in Trauma and Emergency General Surgery Patients: A Systematic Review.

BACKGROUND: Appropriate venous thromboembolism (VTE) chemoprophylaxis in trauma and emergency general surgery (EGS) patients is crucial. OBJECTIVE: The purpose of this study is to review the recent literature and offer recommendations for VTE chemoprophylaxis in trauma and EGS patients. METHODS: We conducted a literature search from 2000 to 2021 for articles investigating VTE chemoprophylaxis in adult trauma and EGS patients. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. RESULTS: Our search resulted in 34 articles. Most studies showed low-molecular-weight heparin (LMWH) is similar to unfractionated heparin (UFH) for VTE prevention; however, LMWH was more commonly used. Adjusted chemoprophylaxis dosing did not change the VTE rate but the timing did. Direct oral anticoagulants (DOACs) have been shown to be safe and effective in trauma and traumatic brain injury (TBI)/spinal cord injury (SCI). Studies showed VTE prophylaxis in EGS can be inconsistent and improves with guidelines that lower VTE events. CONCLUSIONS: There may be no benefit to receiving LMWH over UFH in trauma patients. In addition, different drugs under the class of LMWH do not change the incidence of VTE. Adjusted dosing of enoxaparin does not seem to affect VTE incidence. The use of DOACs in the trauma TBI and SCI setting has been shown to be safe and effective in reducing VTE. One important consideration with VTE prophylaxis may be the timing of prophylaxis initiation, specifically as it relates to TBI, with a higher likelihood of developing VTE as time progresses. EGS patients are at a high risk of VTE. Improved compliance with clinical guidelines in this population is correlated with decreased thrombotic events.

Post-traumatic Splenic Injury Outcomes for Nonoperative and Operative Management: A Systematic Review.

BACKGROUND: Splenectomies are widely performed, but there exists controversy regarding care for splenic injury patients. The purpose of this study is to provide a comprehensive review of the literature over the last 20 years for operative management (OM) versus nonoperative management (NOM) versus splenic artery embolization (SAE) for traumatic splenic injuries and associated outcomes. METHODS: A review of literature was performed following the PRISMA guidelines through a search of PubMed, EMBASE, Cochrane Library, JAMA Network, and SAGE journals from 2000 to 2020 regarding splenic injury in trauma patients and their management. Articles were then selected based on inclusion/exclusion criteria with GRADE criteria used on the included articles to assess quality. RESULTS: Twenty retrospective cohorts and one prospective cohort assessed patients who received OM versus NOM or SAE. Multiple studies indicated that NOM, in properly selected patients, provided better outcomes than its operative counterpart. CONCLUSION: This review provides additional evidence to support the NOM of splenic injuries for hemodynamically stable patients with benign abdomens as it accounts for consistently shorter hospital length of stay, fewer complications, and lower mortality than OM. For hemodynamically unstable patients, management continues to be intervention with surgery. More studies are needed to further investigate outcomes of post-splenectomy patients based on grade of injury, hemodynamic status, type of procedure (i.e., SAE), and failure of NOM in order to provide additional evidence and improve outcomes for this patient population.

Gender distribution among surgical journals' editorial boards: Empowering women surgeon scientists.

BACKGROUND: Gender disparities still exist in the field of academic surgery. Women face additional obstacles obtaining high-ranking, surgical academia positions compared to men, and this may extend to the appointment of editorial board members. We aim to evaluate the gender distribution of editorial board members, associate editors, and editors-in-chief of top US surgical journals and to recommend interventions, which can promote equitable gender representation among editorial boards. METHODS: The study is a cross-sectional analysis using publicly available data regarding the number and proportion of female editorial board members, associate editors, and editors-in-chief from 42 US surgical journals. Descriptive statistics and linear regression were performed with significance defined as P < .05. RESULTS: Of 2,836 editorial board members from 42 US surgical journals, 420 (14.8%) were women. Of 881 associate editors, 118 (13.3%) were women. Only 2/42 (4.8%) of editors-in-chief were women. The mean proportions of female editorial board members and associate editors were 14.5% and 19.5%, respectively. No significant associations were found between the 2019 Scimago Journal & Country Rank indicator nor the 2019 impact factor and the proportion of female editorial board members and female associate editors after adjusting for author H-index. CONCLUSION: Gender disparities are evident in academic surgery, and women comprise a minority of US surgical editorial board members, associate editors, and editors-in-chief. The implementation of women mentorship from senior faculty on behalf of senior residents and junior faculty, as well as journal-facilitated pipeline programs, can diversify editorial board members by increasing women representation and reduce disparities in surgical journal editorial boards.

CANDIED: A Pan-Canadian Cohort of Immune Checkpoint Inhibitor-Induced Insulin-Dependent Diabetes Mellitus.

Immune checkpoint inhibitor (ICI)-induced insulin-dependent diabetes mellitus (IDDM) is a rare but potentially fatal immune-related adverse event (irAE). In this multicentre retrospective cohort study, we describe the characteristics of ICI-induced IDDM in patients treated across five Canadian cancer centres, as well as their tumor response rates and survival. In 34 patients identified, 25 (74%) were male and 19 (56%) had melanoma. All patients received anti-programed death 1 (anti-PD1) or anti-programmed death ligand-1 (anti-PD-L1)-based therapy. From ICI initiation, median time to onset of IDDM was 2.4 months (95% CI 1.1-3.6). Patients treated with anti-PD1/PD-L1 in combination with an anti-cytotoxic T lymphocyte antigen 4 antibody developed IDDM earlier compared with patients on monotherapy (1.4 vs. 3.9 months, p = 0.05). Diabetic ketoacidosis occurred in 21 (62%) patients. Amongst 30 patients evaluable for response, 10 (33%) had a complete response and another 10 (33%) had a partial response. Median overall survival was not reached (95% CI NE; median follow-up 31.7 months). All patients remained insulin-dependent at the end of follow-up. We observed that ICI-induced IDDM is an irreversible irAE and may be associated with a high response rate and prolonged survival.

Treatment for Recurrent Differentiated Thyroid Cancer: A Canadian Population Based Experience.

INTRODUCTION: Management of recurrent differentiated thyroid cancer (DTC) may include surgery, radioactive iodine (RAI), and external beam radiotherapy (EBRT). Systemic therapy may also be offered for RAI-refractory DTC. The study objective was to review patterns of practice in British Columbia (BC) for treatment of recurrent DTC, assess rates of RAI-refractory disease, and evaluate outcomes. METHODS: BC Cancer provides cancer care to a population of 4.6 million. A retrospective review of all patients with DTC stage I-IVB disease referred to BC Cancer from 2009 to 2013 was conducted. Patient and DTC characteristics, locoregional and distant recurrence, surgical management, RAI, EBRT, and systemic therapy details were retrospectively collected. Relapse-free survival (RFS), overall survival (OS), and disease-specific survival (DSS) were calculated using the Kaplan-Meier method. RESULTS/DISCUSSION: Some 1062 DTC patients were identified. Median follow-up was 4.1 years. Baseline characteristics: female 74%, median age 50, papillary/follicular/Hurthle cell 92%/6%/2%. Stage at presentation: I 60%, II 8%, III 22%, IVA/IVB 10%. Locoregional and/or distant recurrence occurred in 136 patients (13%). Locoregional recurrence (n=118) was treated with surgery +/- RAI or EBRT 48%, RAI +/- EBRT 40%, EBRT alone 1%, 11% were observed without treatment. Some 27 patients had a second cancer recurrence. Some 37 patients (3%) developed distant metastatic disease and common sites of distant metastases were: lung 76%, bone 30%, and liver 8%. Some 27 cases (2%) were deemed RAI-refractory. Some six patients (0.6%) received systemic therapy with a vascular endothelial growth factor tyrosine kinase inhibitor (VEGF TKI). Five-year RFS was calculated to be 82%, OS 95%, and DSS 98% for the study population. CONCLUSIONS: In our population-based study cohort, 87% of patients were rendered disease-free by primary disease management. Multi-modality treatment of locoregional recurrence facilitated disease-free status in the majority of patients (67%). RAI-refractory disease developed in 2% of patients and despite a significant number of metastatic recurrences, only a small number of patients received systemic therapy.

Diabetic Pharmacotherapy and Endometrial Cancer Risk Within a Publicly Funded Health Care System.

OBJECTIVE: There is conflicting evidence regarding the association between metformin and endometrial cancer risk. The objective of this study was to evaluate the association between type of diabetic pharmacotherapy and endometrial cancer risk within a population-based study. The hypothesis was that metformin was associated with the lowest risk. METHODS: This was a nested case-control study using data from the BC Cancer Registry (2000-2009) and from a province-wide prescription network (PharmaNet) since 1996. Patients were classified by drug exposure (metformin, thiazolidinediones, secretagogues, with or without insulin). The primary analysis was a conditional logistic regression to estimate the odds ratios for endometrial cancer in the drug exposure groups. Sensitivity analysis was carried out to account for uncertainty regarding various parameters. The secondary analysis evaluated the effect of dosage using a principal components analysis. RESULTS: The study cohort comprised 492 cases and 4404 controls. The primary analysis revealed no difference in endometrial cancer risk between those using metformin and those prescribed other classes of medications (OR 1.5, 95% CI 0.9 to 2.4). Women receiving all classes of medications had almost a two-fold increase in risk (OR 1.9, 95% CI 1.1 to 3.3). The secondary analysis revealed an increased risk associated with a greater duration of treatment and number of prescriptions (OR 1.3, 95% CI 1.2 to 1.4). CONCLUSION: In this population-based study, metformin was not associated with a decreased endometrial cancer risk. Women receiving multiple types of medications over a long time had the highest risk, implying that the extent of insulin resistance, rather than the effect of any specific medication, drives endometrial cancer risk.

Exploring the Functional Complementation between Grp94 and Hsp90.

Grp94 and Hsp90 are the ER and cytoplasmic paralog members, respectively, of the hsp90 family of molecular chaperones. The structural and biochemical differences between Hsp90 and Grp94 that allow each paralog to efficiently chaperone its particular set of clients are poorly understood. The two paralogs exhibit a high degree of sequence similarity, yet also display significant differences in their quaternary conformations and ATPase activity. In order to identify the structural elements that distinguish Grp94 from Hsp90, we characterized the similarities and differences between the two proteins by testing the ability of Hsp90/Grp94 chimeras to functionally substitute for the wild-type chaperones in vivo. We show that the N-terminal domain or the combination of the second lobe of the Middle domain plus the C-terminal domain of Grp94 can functionally substitute for their yeast Hsp90 counterparts but that the equivalent Hsp90 domains cannot functionally replace their counterparts in Grp94. These results also identify the interface between the Middle and C-terminal domains as an important structural unit within the Hsp90 family.

Provincial disparities of growth hormone coverage for young adult survivors of paediatric brain tumours across Canada.

BACKGROUND: Young adult survivors of paediatric brain tumours (PBTs) who have been treated with radiation therapy will likely be severely growth hormone-deficient when retested at the achievement of final height. Growth hormone replacement therapy (GHRT) is administered to treat growth hormone deficiency (GHD). Public drug coverage for GHRT falls under the responsibility of provincial governments across Canada. This study sought to determine the extent of public drug coverage and cost in each Canadian province for GHRT to treat GHD during adulthood for young adult survivors of PBTs. METHODS: Data were collected from provincial government resources and drug formularies from 2012-2013 on the extent of coverage for GHRT based on a clinical case scenario representative of a young adult survivor of a PBT with childhood-onset radiation-induced GHD, the ingredient cost for GHRT and the applicable provincial public drug plan cost-sharing policies. A model was then created to simulate out-of-pocket costs incurred by a young adult male and a young adult female survivor of a PBT for one year of GHRT in each province with applicable cost-sharing arrangements and levels of low annual individual total income that best represent the majority of young adult survivors of PBTs. Out-of-pocket costs were expressed as a percentage of annual income. Comparisons were made between provinces descriptively, and variation among provinces was summarized statistically. RESULTS: Alberta, Manitoba, Ontario, Quebec, New Brunswick, and Newfoundland and Labrador provide coverage for GHD during adulthood on a case-by-case basis, while British Columbia, Saskatchewan, Nova Scotia and Prince Edward Island provide no coverage. The percentage of annual income to fund GHRT across the provinces without public coverage ranged from 14.4% to 25.5% for males and 21.5% to 38.3% for females, and with public coverage was 0.0% to 4.1% for males and 0.0% to 5.0% for females. INTERPRETATION: There are considerable out-of-pocket costs and variation in coverage provided by provincial public drug plans to fund GHRT for young adult survivors of PBTs with GHD. The implementation of a national drug formulary could potentially prevent undue financial hardship and remove disparities resulting from variations in provincial drug plans.

Phenotypic modifications in ovarian cancer stem cells following Paclitaxel treatment.

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy. Despite initial responsiveness, 80% of EOC patients recur and present with chemoresistant and a more aggressive disease. This suggests an underlying biology that results in a modified recurrent disease, which is distinct from the primary tumor. Unfortunately, the management of recurrent EOC is similar to primary disease and does not parallel the molecular changes that may have occurred during the process of rebuilding the tumor. We describe the characterization of unique in vitro and in vivo ovarian cancer models to study the process of recurrence. The in vitro model consists of GFP+/CD44+/MyD88+ EOC stem cells and mCherry+/CD44-/MyD88- EOC cells. The in vivo model consists of mCherry+/CD44+/MyD88+ EOC cells injected intraperitoneally. Animals received four doses of Paclitaxel and response to treatment was monitored by in vivo imaging. Phenotype of primary and recurrent disease was characterized by quantitative polymerase chain reaction (qPCR) and Western blot analysis. Using the in vivo and in vitro models, we confirmed that chemotherapy enriched for CD44+/MyD88+ EOC stem cells. However, we observed that the surviving CD44+/MyD88+ EOC stem cells acquire a more aggressive phenotype characterized by chemoresistance and migratory potential. Our results highlight the mechanisms that may explain the phenotypic heterogeneity of recurrent EOC and emphasize the significant plasticity of ovarian cancer stem cells. The significance of our findings is the possibility of developing new venues to target the surviving CD44+/MyD88+ EOC stem cells as part of maintenance therapy and therefore preventing recurrence and metastasis, which are the main causes of mortality in patients with ovarian cancer.

Persistence of sleep-associated decrease in GnRH pulse frequency in the absence of gonadal steroids.

CONTEXT: There is dramatic slowing of GnRH pulse frequency during sleep in the early follicular phase of the menstrual cycle, but it is unknown whether this represents a primary effect of sleep or is dependent upon the sex steroid environment. OBJECTIVES: Our objective was to determine 1) whether sleep affects GnRH pulse frequency in postmenopausal women (PMW) in whom gonadal hormones are low and 2) whether this relationship changes with aging. DESIGN AND SETTING: Studies were performed in the Clinical Research Center of an academic medical center. SUBJECTS: Subjects included healthy PMW, 45-55 (n = 8) and 70-80 (n = 6) years old. INTERVENTIONS: Subjects were studied during one night of polysomnographic-recorded sleep and one night of monitored wake during which blood was sampled every 5 min for 8 h. MAIN OUTCOME MEASURES: Pulsatile secretion of free α-subunit (FAS), a marker of GnRH secretion, was assessed. RESULTS: There were no differences in sleep macroarchitecture or sleep efficiency [75 ± 12% (mean ± sd)] between older and younger PMW. The FAS interpulse interval was longer during sleep than nighttime wake in all women (60.5 ± 4.3 vs. 52.0 ± 2.8 min, P = 0.03) with a similar effect in the two groups. FAS pulse amplitude did not differ between sleep and wake periods (474.8 ± 36.7 vs. 478.2 ± 36.5 ng/liter, P = 0.9). CONCLUSIONS: Sleep is associated with a significant decline in GnRH pulse frequency in both older and younger PMW. Its persistence in PMW reinforces the important connection between sleep and GnRH secretion.

Gender differences in thyroid cancer: a critical review.

It has long been known that the incidence of thyroid cancer in women is significantly higher than that in men. The objective of this article is to review gender differences in thyroid cancer, as well as epidemiological, clinical and experimental research on the role of sex hormones, their receptors and other molecular factors in this well-established thyroid cancer gender discrepancy. Although more common in women, thyroid cancer typically presents at a more advanced stage and with a worse disease prognosis in men. Clinical evidence on the impact of estrogen and other sex hormones on thyroid cancer has remained inconclusive, although numerous experimental studies have suggested that these hormones and their receptors may play a role in tumorigenesis and tumor progression. Studies of thyroid cancer cell lines suggest that an imbalance between the two estrogen receptor (ER) isoforms, α and ß, may be responsible for the cell proliferation seen with estrogen treatment. Expression studies on thyroid tumors indicate that they express ER and possibly progesterone receptors and androgen receptors, but there is conflicting evidence as to whether or not there is a difference in receptor status between thyroid cancers, benign thyroid lesions and normal thyroid tissue. There have been few studies evaluating the ERα/ERß profiles in thyroid tumors and normal thyroid tissue. Our understanding of the underlying basis for sex differences in thyroid cancer has improved over the last few decades, but the relationship between gender and thyroid cancer risk has remained elusive. Areas for future research include ERα/ERß profiling of normal and neoplastic thyroid tissue, association between ER status and tumor dedifferentiation, and evaluation of the signaling pathways by which estrogen and other sex steroids exert their effects on thyroid cancer cells. Sex steroid receptors, and then downstream signaling pathways, represent promising future therapeutic targets for thyroid cancer treatment, and further study is required.

Inverse relationship between luteinizing hormone and body mass index in polycystic ovarian syndrome: investigation of hypothalamic and pituitary contributions.

CONTEXT: Patients with polycystic ovarian syndrome (PCOS) have increased LH relative to FSH, but LH is modified by body mass index (BMI). OBJECTIVE: The objective of the study was to determine whether the impact of BMI on neuroendocrine dysregulation in PCOS is mediated at the hypothalamic or pituitary level. PARTICIPANTS/INTERVENTIONS/SETTING: Twenty-four women with PCOS across a spectrum of BMIs underwent frequent blood sampling, iv administration of GnRH (75 ng/kg), and sc administration of the NAL-GLU GnRH antagonist (5 microg/kg) in the General Clinical Research Center at an academic hospital. MAIN OUTCOME MEASURES: LH pulse frequency and LH response to submaximal GnRH receptor blockade were used as measures of hypothalamic function; LH response to GnRH was used as a measure of pituitary responsiveness. RESULTS: BMI was negatively correlated with mean LH, LH/FSH, and LH pulse amplitude. There was no effect of BMI on LH pulse frequency. Percent inhibition of LH was decreased in PCOS, compared with normal women (53.9 +/- 1.5 vs. 63.1 +/- 4.1, respectively; P < 0.01), suggesting an increase in the amount of endogenous GnRH, but was not influenced by BMI. Pituitary responsiveness to GnRH was inversely correlated with BMI (peak LH, R = -0.475, P < 0.02; and LH area under the curve R = -0.412, P < 0.02). CONCLUSIONS: LH pulse frequency and quantity of GnRH are increased in PCOS, but there is no influence of BMI on either marker of hypothalamic function. The pituitary response to a weight-based dose of GnRH is inversely related to BMI in PCOS. These studies suggest that the effect of BMI on LH is mediated at a pituitary and not a hypothalamic level in PCOS.

Risks and benefits of hormone replacement therapy: the evidence speaks.

Until recently, observational studies suggested a decreased risk of cardiovascular disease, osteoporotic fractures, cognitive decline and colon cancer with the use of hormone replacement therapy (HRT). Recent randomized controlled trials have failed to show a protective effect of HRT in reducing the risk of coronary artery disease and instead have revealed an increased risk of heart disease, stroke, invasive breast cancer and venous thromboembolism, but a decreased risk of colorectal cancer and osteoporotic fractures. In this article we review the current evidence of the risks and benefits of HRT.

Evidence that GnRH decreases with gonadal steroid feedback but increases with age in postmenopausal women.

UNLABELLED: Studies of the effects of gonadal steroid negative feedback and age on the hypothalamic-pituitary axis in postmenopausal women (PMW) have identified significant but inconsistent changes in gonadotropin dynamics. In the current study, we investigated the effect of gonadal steroid replacement and age on overall GnRH secretion estimated by using submaximal GnRH receptor blockade. Twenty-four healthy PMW, 45-55 yr (n = 13) and 70-80 yr (n = 11), were studied. Subjects were studied at baseline (BL) on no hormone replacement therapy, after 1 month of transdermal estrogen (50 microg/d; E) and again after a further month of E and 7 d of transvaginal progesterone (100 mg bid; E + P). At each admission, blood was sampled every 30 min for 4 (BL and E) or 8 h (E + P) before and 10 h after sc administration of a submaximal dose (5 microg/kg) of the NAL-GLU GnRH antagonist ([Ac-D2Nal(1), D4ClPhe(2), DPal(3), Arg(5), DGlu(AA)(6), DAla(10)] GnRH). Percent inhibition of LH was calculated by expressing the difference between the nadir following GnRH antagonist administration and the preantagonist baseline as a percent of the baseline. Physiologic E and P levels were achieved with the appropriate hormone replacement regimens. Mean LH levels decreased from baseline with E alone and decreased further with E + P (81.4 +/- 6.6, 68.2 +/- 8.1 and 48.0 +/- 4.3 IU/liter, respectively; P < 0.005). Percent inhibition of LH following submaximal GnRH receptor blockade decreased with age (57.6 +/- 1.8% in young PMW vs. 51.4 +/-2.2% in old PMW; P < 0.05) implying an increase in GnRH secretion with age. There was an increase in percent inhibition of LH in response to submaximal GnRH receptor blockade with E and a further increase with E + P (54.8 +/-1.5%, 58.8 +/- 1.9% and 69.9 +/- 2.8%, respectively; P < 0.05), indicating a progressive decrease in endogenous GnRH secretion with gonadal steroid feedback. Mean LH and FSH levels were lower at baseline in old compared with young PMW. However, the effect of gonadal steroid feedback on endogenous GnRH secretion was similar in young and old PMW. IN CONCLUSION: 1) The overall quantity of GnRH secretion increases with age as demonstrated by the progressive decrease in LH inhibition following submaximal GnRH antagonist administration with increasing age; 2) E negative feedback is associated with a decrease in GnRH secretion (as indicated by an increased percent inhibition of LH following submaximal GnRH receptor blockade); 3) E2 and P are associated with a further decease in overall amount of GnRH secreted; and 4) Age does not dampen the inhibition of hypothalamic GnRH secretion by E and P in PMW.

Negative feedback effects of gonadal steroids are preserved with aging in postmenopausal women.

There is now evidence for alterations in the neuroendocrine control of the reproductive axis with aging, but its sensitivity to gonadal steroid negative feedback remains controversial. To examine the independent effect of age and gonadal steroid negative feedback, younger (45-55 yr; n = 7) and older (70-80 yr; n = 6) postmenopausal women (PMW) were studied at baseline on no HRT, after 1 month of transdermal estrogen (50 microg/d; E) and again after a further month of E and 7 d of transvaginal progesterone (P) (100 mg bid; E + P). At each admission, blood was sampled every 5 min for 8 h for measurement of gonadotropin free alpha-subunit (FAS), which was used as a marker of GnRH pulse frequency. LH and FSH were measured in pooled samples. Midfollicular and midluteal phase levels of E2 and P were achieved during the E and E + P treatments and were not different between younger and older PMW. There was a negative feedback effect of E and E + P on mean LH (P < 0.0001) and an additional effect of age (P < 0.003), with older women having lower values throughout. Mean FSH was also decreased with E and E + P (P < 0.0001) and was consistently lower in the older women (P < 0.05). Mean FAS levels decreased with hormonal treatment (P < 0.0001) and age (P < 0.001), but the effect of hormonal treatment was attenuated in the older group (P < 0.005). FAS pulse frequency was unchanged with addition of E, but dramatically decreased with E + P (P < 0.002). Both hormonal replacement (P < 0.05) and age (P < 0.005) decreased FAS pulse amplitude, an effect that was attributable entirely to E as there was no additional change with E + P. These studies indicate that: 1) both age and gonadal steroids independently decrease mean LH, FSH, and FAS in PMW; 2) responsiveness to steroid negative feedback on FAS is attenuated with aging in absolute but not relative terms, whereas the effect on mean levels of LH and FSH is clearly preserved; and 3) FAS pulse frequency is unchanged with E2 administration but decreases dramatically with addition of P in both old and young PMW.