Thyroid cancer has been increasing in incidence, with the number of reported cases in the US rising by 25% over the last 3 years. With growing technological advances in the field and improved contributions of diagnostics, surgical decision-making and operative planning have taken on new challenges. Herein, we review the current clinical practice recommendations and active areas of surgical controversy, reflective of the most recently published professional consensus guidelines and a systematic review of the literature.
Developments in technology have led to a rapid progress in robotic endocrine surgery applications. With the advent of minimally invasive techniques in thyroid surgery, robot-assisted transaxillary thyroid surgery (RATS) has emerged as one of the most promising approaches. Its main advantages are improved cosmetic outcome, avoiding cervical incisions, thereby increasing patient satisfaction, and improved visualization, arms articulations, and precision, resulting in fewer surgical complications. The main disadvantages are potential new injuries to the brachial plexus, esophagus, and trachea, longer operative time, and increased cost compared to conventional thyroidectomy. In skilled hands, RATS is a safe alternative to conservative thyroidectomy and should be presented to patients with aesthetic concerns. As with any new emerging technique, careful patient selection is crucial, and further evidence must be sought to confirm its indications over time.
Objective: To compare pathologic results obtained via in-office transnasal fiberoptic laryngoscopy (TFL) to those of subsequent direct laryngoscopy in order to assess the accuracy of TFL as a diagnostic tool.
Patients: One hundred and seventeen patients with suspicious laryngeal lesions.
Methods: All patients underwent in-office biopsies. All patients with malignant diagnosis were referred to treatment. All patients with benign diagnosis or carcinoma in situ were referred to direct laryngoscopy for definitive diagnosis. The pathological results of the specimens from both procedures were compared.
Results: Adequate tissue for diagnostic purposes was obtained in 110 of 117 in-office transnasal fiberoptic laryngoscopy biopsies (94.0%). The biopsy results revealed invasive carcinoma in 42 patients (38.2%), carcinoma in situ (CIS) in 17 patients (15.4%), and benign lesions in 51 patients (46.4%). All patients with benign pathologies and carcinoma in situ were referred to biopsy under direct laryngoscopy (five patients refused and were removed from the statistics). The final pathologies identified from the biopsies on direct laryngoscopy revealed that there was an underestimation of the transnasal fiberoptic laryngoscopy results in 33 patients (a false negative rate of 31.4%, 33/105) and an overestimation in one patient. The sensitivity of transnasal fiberoptic laryngoscopy biopsy compared with direct laryngoscopy biopsy was 70.6% and the specificity was 96.7%.
Conclusions: TFL with biopsy is easy, safe, and cost-effective but raises serious doubts about its clinical value due its low sensitivity rate for diagnosing suspicious lesions of the larynx. As such, it is recommended that all patients with a suspicious lesion diagnosed by TFL biopsy as being benign or CIS should be referred to direct laryngoscopy for verification of the findings.
With the discovery of the JAK2V617F mutation in patients with Philadelphia chromosome-negative (Ph-) myeloproliferative neoplasms (MPNs) in 2005, major advances have been made in the diagnosis of MPNs, in understanding of their pathogenesis involving the JAK/STAT pathway, and finally in the development of novel therapies targeting this pathway. Nevertheless, it remains unknown which mutations exist in approximately one-third of patients with non-mutated JAK2 or MPL essential thrombocythemia (ET) and primary myelofibrosis (PMF). At the end of 2013, two studies identified recurrent mutations in the gene encoding calreticulin (CALR) using whole-exome sequencing. These mutations were revealed in the majority of ET and PMF patients with non-mutated JAK2 or MPL but not in polycythemia vera patients. Somatic 52-bp deletions (type 1 mutations) and recurrent 5-bp insertions (type 2 mutations) in exon 9 of the CALR gene (the last exon encoding the C-terminal amino acids of the protein calreticulin) were detected and found always to generate frameshift mutations. All detected mutant calreticulin proteins shared a novel amino acid sequence at the C-terminal. Mutations in CALR are acquired early in the clonal history of the disease, and they cause activation of JAK/STAT signaling. The CALR mutations are the second most frequent mutations in Ph- MPN patients after the JAK2V617F mutation, and their detection has significantly improved the diagnostic approach for ET and PMF. The characteristics of the CALR mutations as well as their diagnostic, clinical, and pathogenesis implications are discussed in this review.
It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important impli-cations for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the hu-man gene pool, thereby enhancing the potential for human evolution. The increase in human popula-tion size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual het-erozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.
Intelligent Design (ID) burst onto the scene in 1996, with the publication of Darwin’s Black Box by Mi-chael Behe. Since then, there has been a plethora of articles written about ID, both pro and con. How-ever, most of the articles critical of ID deal with peripheral issues, such as whether ID is just another form of creationism or whether ID qualifies as science or whether ID should be taught in public schools. It is our view that the central issue is whether the basic claim of ID is correct. Our goal is fourfold: (I) to show that most of the proposed refutations of ID are unconvincing and/or incorrect, (II) to describe the single fundamental error of ID, (III) to discuss the historic tradition surrounding the ID controversy, showing that ID is an example of a “god-of-the-gaps” argument, and (IV) to place the ID controversy in the larger context of proposed proofs for the existence of God, with the emphasis on Jewish tradition.
Heparanase is an endo-beta-D-glucuronidase that cleaves heparan sulfate (HS) side chains at a limited number of sites, activity that is strongly implicated with cell invasion associated with cancer metastasis, a consequence of structural modification that loosens the extracellular matrix barrier. Heparanase activity is also implicated in neovascularization, inflammation, and autoimmunity, involving migration of vascular endothelial cells and activated cells of the immune system. The cloning of a single human heparanase cDNA 10 years ago enabled researchers to critically approve the notion that HS cleavage by heparanase is required for structural remodeling of the extracellular matrix (ECM), thereby facilitating cell invasion. Heparanase is preferentially expressed in human tumors and its over-expression in tumor cells confers an invasive phenotype in experimental animals. The enzyme also releases angiogenic factors residing in the tumor microenvironment and thereby induces an angiogenic response in vivo. Heparanase up-regulation correlates with increased tumor vascularity and poor postoperative survival of cancer patients. These observations, the anticancerous effect of heparanase gene silencing and of heparanase-inhibiting molecules, as well as the unexpected identification of a single functional heparanase suggest that the enzyme is a promising target for anticancer drug development. Progress in the field expanded the scope of heparanase function and its significance in tumor progression and other pathologies such as inflammatory bowel disease and diabetic nephropathy. Notably, while heparanase inhibitors attenuated tumor progression and metastasis in several experimental systems, other studies revealed that heparanase also functions in an enzymatic activity-independent manner. Thus, point-mutated inactive heparanase was noted to promote phosphorylation of signaling molecules such as Akt and Src, facilitating gene transcription (i.e. VEGF) and phosphorylation of selected Src substrates (i.e. EGF receptor). The concept of enzymatic activity-independent function of heparanase gained substantial support by elucidation of the heparanase C-terminus domain as the molecular determinant behind its signaling capacity and the identification of a human heparanase splice variant (T5) devoid of enzymatic activity, yet endowed with protumorigenic characteristics. Resolving the heparanase crystal structure will accelerate rational design of effective inhibitory molecules and neutralizing antibodies, paving the way for advanced clinical trials in patients with cancer and other diseases involving heparanase.
Patients with type 2 diabetes (T2D) are at increased risk of developing cancer. This evidence arises from numerous epidemiologic studies that relate a positive association between T2D and cancer. In-vitro and several in-vivo experiments have attempted to discern the potential mechanistic factors involved in this relationship. Candidates include hyperinsulinemia, insulin-like growth factor-1 (IGF-1), and insulin-like growth factor-2 (IGF-2) signaling. These studies demonstrated that increased insulin, IGF-1, and IGF-2 signaling through the insulin receptor and IGF-1 receptor can induce cancer development and progression.
Evaluation of patients after penetrating neck injury has evolved over time. Previously, location of injury and symptoms were used to determine management. The contemporary management of penetrating neck injuries relies on physical examination. Patients with hard signs of vascular or aerodigestive tract injury require immediate operation, regardless of location of injury. Those with no signs can be observed. For the remainder with soft signs multidetector, computed tomographic angiography (MDCTA) is a highly sensitive and specific screening modality for evaluating the vasculature and aerodigestive structures in the neck. Utilizing MDCTA, the patient can be safely directed towards operative intervention, observation, or further investigation.
Surprisingly, an utterly imaginative “portrait” has become synonymous with Maimonides forever. How and when did this particular portrait become associated with Maimonides? This and many other intriguing questions regarding this portrait are systematically addressed, and its origins, possible inspiration, and hidden objectives are revealed.
