Testing the external validity of the POUT III trial (adjuvant platnium-based chemotherapy in upper tract urothelial carcinoma) in a North American cohort

OBJECTIVE

The European POUT III randomized controlled trial provided level-one evidence that adjuvant platinum-based chemotherapy is the standard of care following nephroureterectomy (RNU) for locally invasive or node-positive upper tract urothelial carcinoma. We aim to assess this European randomized controlled trial's generalizability (external validity) to a North American cohort, using a nationwide database.

MATERIALS AND METHODS

To compare trial patients with those seen in real-world practice, we simulated the trial inclusion criteria using data from the National Cancer Database (NCDB). We identified patients with histologically confirmed transitional cell carcinoma who underwent RNU. The available demographic characteristics of the NCDB cohort were compared with the POUT III trial cohort using Chi-squared test.

RESULTS

The NCDB cohort (n = 3,380) had a significantly higher proportion of older patients (age ≥ 80: 23.5% vs. 5%), and more males (68% vs. 56.2%) than the POUT cohort (Table 1, both p < 0.001). Additionally, the rate of advanced nodal disease was higher in the NCDB (N1 9.6%, N2 9.3%) than in the POUT (N1 6%, N2 3%) cohort (p < 0.001). A more extensive lymph node dissection was performed in NCDB vs. POUT patients (node≥10 10.9% vs. 3%, p < 0.001). Sensitivity analysis removing all subjects with a Charlson Comorbidity Index > 0 did not change the significance of any results.

CONCLUSIONS

While the primary disease stage was similar, the rate of advanced nodal disease was significantly higher in NCDB, which might be explained partially by the more extensive lymph node dissection performed in the latter. These differences warrant caution when applying the POUT III findings to North American patients.

Bibliometric analysis of machine learning trends and hotspots in arthroplasty literature over 31 years

Background

Artificial intelligence has demonstrated utility in orthopedic research. Algorithmic models derived from machine learning have demonstrated adaptive learning with predictive application towards outcomes, leading to increased traction in the literature. This study aims to identify machine learning arthroplasty research trends and anticipate emerging key terms.

Methods

Published literature focused on machine learning in arthroplasty from 1992 to 2023 was selected through the Web of Science Core Collection of Clarivate Analytics. Following that, bibliometric indicators were attained and brought in to perform an additional examination using Bibliometrix and VOSviewer to identify historical and present patterns within the literature.

Results

A total of 235 documents were obtained through bibliometric sourcing based on machine learning applications within the arthroplasty literature. Thirty-four countries published articles on the topic, and the United States was demonstrated to be the largest global contributor. Four hundred-five institutions internationally contributed articles, with Harvard Medical School and the University of California system as the most relevant institutes, with 75 and 44 articles produced, respectively. Kwon YM was the most productive author, while Haeberle HS and Ramkumar PN were the most impactful based on h-index. The Thematic map and Co-occurrence visualization helped identify both major and niche themes present in the scientific databases.

Conclusions

Machine learning in arthroplasty research continues to gain traction with a growing annual production rate and contributions from international authors and institutions. Institutions and authors based in the United States are the leading contributors to machine learning applications within arthroplasty research. This research discerns trends that have occurred, are presently ongoing, and are emerging within this field, aiming to inform future hotspot development.

Hamstring Anterior Cruciate Ligament Autograft Contributes to a Delayed Symptomatic Cyclops Lesion: A Case Report

Cyclops lesions are characterized as fibroid nodules with granulation tissue that looks similar to a cyclops eye during arthroscopy. These are rare postoperative complications following anterior cruciate ligament reconstruction (ACLR), presenting typically within six months of their reconstruction. This case report presents a 21-year-old male, three years following hamstring autograft ACLR, with a symptomatic cyclops lesion. Contrary to the reported literature, this delayed presentation showed a painful flexion contracture of the knee and intraoperative findings consistent with a cyclops lesion. The treatment consisted of surgical debridement and notchplasty with subsequent posterior medial and lateral meniscal horn repairs. This case report presents a lesson to indicate that cyclops lesions can occur in a delayed setting following ACLR and to show a technique for successful surgical management of the lesion.

What are patients asking and reading online? An analysis of online patient searches for rotator cuff repair

BACKGROUND

Patients undergoing rotator cuff surgery often search the internet for information regarding the procedure. One popular source, Google, compiles frequently asked questions and links to websites that may provide answers. This study provides an analysis of the most frequently searched questions associated with rotator cuff surgery. We hypothesize that there will be distinct search patterns associated with online queries about rotator cuff surgery that could provide unique insights into patient concerns.

METHODS

A set of search terms were entered into Google Web Search using a clean-install Google Chrome browser. Frequently associated questions and their webpages were extracted to a database via a data mining extension. Questions were categorized by topics relevant for rotator cuff arthroscopy. Websites were categorized by source and scored for quality using the JAMA Benchmark Criteria. Pearson's χ2 tests were used to analyze nominal data. Student t tests were performed to compare JAMA Benchmark Scores.

RESULTS

Of the 595 questions generated from the initial search, 372 unique questions associated with 293 websites were extracted and categorized. The most popular question topics were activities/restrictions (20.7%), pain (18.8%), and indications/management (13.2%). The 2 most common websites searched were academic (35.2%) and medical practice (27.4%). Commercial websites were significantly more likely to be associated with questions about cost (57.1% of all cost questions, P = .01), anatomy/function (62.5%, P = .001), and evaluation of surgery (47.6%, P < .001). Academic websites were more likely to be associated with questions about technical details of surgery (58.1%, P < .001). Medical practice and social media websites were more likely associated with activities/restrictions (48.1%, P < .001, and 15.6%, P < .001, respectively). Government websites were more likely associated with timeline of recovery (12.8%, P = .01). On a scale of 0-4, commercial and academic websites had the highest JAMA scores (3.06 and 2.39, respectively).

CONCLUSION

Patients seeking information regarding rotator cuff repair primarily use the Google search engine to ask questions regarding postoperative activity and restrictions, followed by pain, indications, and management. Academic websites, which were associated with technical details of surgery, and medical practice websites, which were associated with activities/restrictions, were the 2 most commonly searched resources. These results emphasize the need for orthopedic surgeons to provide detailed and informative instructions to patients undergoing rotator cuff repair, especially in the postoperative setting.

Who Is Shaping the Future of Academic Urology? A Descriptive Analysis of Residency Program Directors

OBJECTIVE

To characterize the demographics, educational background, and scholarly characteristics of current urology residency program directors (PDs).

METHODS

Urology programs were identified by the listing on the "Accredited US Urology Programs" section of American Urological Association website as of October 2021. Demographics and academic data were collected via publicly available department website and Google search engine. Metrics obtained included years of service as PD from time of appointment, sex, medical school/residency/fellowship, all-time H-index, dual degrees obtained, and professorial ranking.

RESULTS

One hundred and forty-seven accredited urological residencies were reviewed; every PD was included. The majority were male (78%) and fellowship trained (68%). Women represented only 22% of PDs. The median active time served as PD, as of 11/2021, was 4years (IQR: 2-7). Forty (28%) were faculty at the same program they completed their residency. The median all-time H-index was 12 (IQR: 7-19; range 1-61). Twelve PDs also served as chair of their department.

CONCLUSION

The vast majority of PDs are male, fellowship trained, and have served for less than 5years. Future studies are necessary to follow the trends of representation in leaders of urology residency programs.

Top 100 Urology Influencers on Twitter: Is Social Media Influence Associated with Academic Impact?

BACKGROUND

Social media use in medicine has exploded, with uptake by most physicians and patients. There is a risk of dissemination of inaccurate information about urological conditions on social media. Physicians, as key opinion leaders, must play a role in sharing evidence-based information through social media.

OBJECTIVE

To identify and describe the top 100 urology influencers on the Twitter social media platform and to correlate Twitter influence with academic impact in urology.

DESIGN, SETTING, AND PARTICIPANTS

Twitter influence scores for the search topic "urology" were collected in April 2022 using published methodology. The top 100 personal accounts with the highest computed scores were linked to individuals' names, all-time h index, geographic location, specialty, attributed sex, and board certification status in this cross-sectional study.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We examined the correlation between influence rank and h index.

RESULTS AND LIMITATIONS

Of the top 100 Twitter influencers on the topic of urology, the majority are from the USA (64%), male (85%), and practicing urologists (91%). Some 93% of US urology influencers are board-certified. Only 22 of the 50 US states are represented. The second most frequent country is the UK, with ten urology influencers. The median all-time h index is 42 (interquartile range 28.25-58). There is a weak positive correlation between influence rank and h index (r = 0.23; p = 0.02). Limitations of the study include the inability to validate the accuracy of the proprietary ranking algorithm and investigation of just one social media platform.

CONCLUSIONS

The top Twitter influencers in urology are mostly board-certified US urologists. Collectively, influencers have a relatively greater academic impact in comparison to the average urologist, although there is a weak positive correlation between Twitter influence and h index among top Twitter influencers.

PATIENT SUMMARY

Given the explosion of medical information on Twitter, we report the personal accounts with the greatest impact for the topic of "urology". We found that most urology influencers on Twitter are US board-certified urologists with a strong research history.

Ecological segregation moderates a climactic conclusion to trout hybridization

For decades, it has been assumed that introgressive hybridization between introduced rainbow trout and native cutthroat trout in western North America will lead to genomic extinction of the latter. A broad-scale re-examination of their interaction indicates that ecological differences between these species and demographic processes are dictating the location and extent of their hybrid zones, and that runaway introgression between these taxa is unlikely.

Climate, Demography, and Zoogeography Predict Introgression Thresholds in Salmonid Hybrid Zones in Rocky Mountain Streams

Among the many threats posed by invasions of nonnative species is introgressive hybridization, which can lead to the genomic extinction of native taxa. This phenomenon is regarded as common and perhaps inevitable among native cutthroat trout and introduced rainbow trout in western North America, despite that these taxa naturally co-occur in some locations. We conducted a synthetic analysis of 13,315 genotyped fish from 558 sites by building logistic regression models using data from geospatial stream databases and from 12 published studies of hybridization to assess whether environmental covariates could explain levels of introgression between westslope cutthroat trout and rainbow trout in the U.S. northern Rocky Mountains. A consensus model performed well (AUC, 0.78–0.86; classification success, 72–82%; 10-fold cross validation, 70–82%) and predicted that rainbow trout introgression was significantly associated with warmer water temperatures, larger streams, proximity to warmer habitats and to recent sources of rainbow trout propagules, presence within the historical range of rainbow trout, and locations further east. Assuming that water temperatures will continue to rise in response to climate change and that levels of introgression outside the historical range of rainbow trout will equilibrate with those inside that range, we applied six scenarios across a 55,234-km stream network that forecast 9.5–74.7% declines in the amount of habitat occupied by westslope cutthroat trout populations of conservation value, but not the wholesale loss of such populations. We conclude that introgression between these taxa is predictably related to environmental conditions, many of which can be manipulated to foster largely genetically intact populations of westslope cutthroat trout and help managers prioritize conservation activities.

Immunosenescence and infectious diseases

Infectious diseases are major causes, with malignancies, of morbidity and mortality in the elderly. Increased susceptibility to infections may result from underlying dysfunction of an aged immune system; moreover, inappropriate immunologic functions associated with aging can determine an insufficient response to vaccines. Impairments of cellular, humoral and innate immunity in the elderly, contributing to increased incidence of infectious diseases, are discussed in this review.

[Blood coagulation changes and neoplastic pathology]

Cancer patients show an increased susceptibility to develop thromboembolic diseases, suggesting that disorders of coagulation are very common in this pathology. Tumor cells possess the capacity to interact with the hemostatic system, activating the coagulation cascade and stimulating the prothrombotic properties of other blood cell components; the same events while inducing a hypercoagulable state, also contribute to the processes of tumor growth, neoangiogenesis and metastatic formation. Multiple risk factors associated with malignant disease contribute to the hypercoagulability state: stasis induced by prolonged bed rest, vascular invasion by the tumor and iatrogenic complications including the use of central vein catheters and chemotherapy. Several tests have been developed to assess the hypercoagulable state, however their clinical significance still needs to be defined, especially in terms of their predictive value for thrombosis. Clinical manifestations vary from localized deep venous thrombosis (DVT) or pulmonary embolism, more generally associated with solid tumors, to disseminated intravascular coagulation, frequent in hematologic malignancies and metastatic cancer. Diagnosis of idiopathic DVT, in the absence of other risk factors, could indicate the presence of occult cancer, but the usefulness of an extensive work-up to detect malignancy in terms of cost to benefit ratio still has to be demonstrated. Patients with cancer and thromboembolism must be treated with anticoagulant therapy; a large number of studies have shown that either low molecular weight heparins or standard unfractionated heparin for the treatment of acute deep vein thrombosis in hospitalized patients are equally safe and effective; however, the first treatment has been reported to be associated with a lower mortality. After an episode of thrombosis the patients should be protected by a long term course of oral anticoagulation, remaining high the risk of recurrence for as long as the cancer is active.

Immunophenotypical changes of T lymphocytes in the elderly

BACKGROUND

Substantial changes in both representation and function of T lymphocyte subsets have been reported with advancing age. However, till now, no systematic studies focused on age-dependent changes in the expression intensity of the major T lymphocyte surface receptors.

OBJECTIVE

The present study was undertaken in order to establish age-related differences in lymphocyte subpopulations by simultaneously measuring three surface antigens in young and elderly people.

METHOD

Peripheral blood T cell subsets from 20 healthy elderly individuals and 15 healthy young adult donors were examined by means of a quantitative three-color flow cytometry method.

RESULTS

Activated (HLA-DR+) and memory (CD45RO+) T cells, CD3+CD7- T lymphocytes, and cells expressing natural killer (NK) markers (CD3-CD56+ NK cells and CD3+CD56+ T lymphocytes) were expanded, whereas T lymphocytes expressing the adhesion molecule CD62L were lower in elderly compared with young donors. In addition to alterations in the percentages of T cell subsets during senescence, several changes in the intensity expression of T cell antigens were also detected. CD3 antigen expression was downregulated on total T lymphocytes as well as on the memory T cell subset, while CD56+ T cells exhibited increased CD3 levels. Moreover, CD2 expression, unchanged on NK cells, was upregulated on T lymphocytes from elderly subjects. CD3+CD7- T cells exhibited increased expression of CD8 antigen, while the intensity expression of HLA-DR on activated T cells and CD7 on both T and NK lymphocytes was decreased. T cells from elderly subjects also exhibited higher expression of CD50 and CD62L adhesion molecules as compared with young ones.

CONCLUSION

These T cell antigen expression modulations during senescence, in addition to the alteration in the frequency of the various T lymphocyte subsets, could contribute to the complex remodeling of the immune function characteristic of the elderly.

Cell proliferation and apoptosis in the immune system in the elderly

Loss of the cell proliferative capability and involution of tissues and organs are among the most important phenomena that characterize the aging process. Some of the aged-linked immune dysfunctions could be partly due to a dysregulation of apoptotic processes and to a lower responsiveness of aged lymphoid cells to activation and proliferation signals. The main changes in proliferative activity and cell death during aging and their impact on the process of immunosenescence are discussed. In fact, a very important function that has been suggested to deteriorate with age and to play a major role in the aging process is the capability of cells from aged subjects to respond to mitogenic stimuli and, consequently, to undergo cell proliferation. However, the cellular activation processes are very complex and the proliferative responses can follow different interconnected signal transduction pathways, and only some of them appear to be modified during age. Moreover, cell growth, immunosenescence, and longevity are strictly interconnected and deeply related to programmed cell death or apoptosis. The cellular equilibrium between cell survival and proliferation, on the one hand, and programmed cell death, on the other hand, seems to be unbalanced with advancing age, although in each type of immune cell it could be differentially modulated, resulting in a variety of clinicopathological consequences. Thus, cell proliferation and cell death are two physiologically active phenomena closely linked and regulated and a failure of these mechanisms determines profound dysregulations of cell homeostasis with major consequences in immune functioning and the onset of autoimmune diseases and cancer, whose incidence appears to be increased in the elderly.

The immune system in the elderly: I. Specific humoral immunity

Profound and complex changes in the immune response occur during the aging process. Immunosenescence is reflected by a sum of disregulations of the immune system and its interaction with other systems. Many of the changes would appear to implicate age-related deficiencies of the immune responses. The term immunosenescence designates therefore a sort of deterioration of the immune function which is believed to manifest itself in the increased susceptibility to cancer, autoimmune disease, and infectious disease. Evidence has been accumulating from several studies which suggest an association between immune function and individual longevity. However, there are observations, especially in very old healthy people, that several immune functions are unexpectedly well preserved and substantially comparable to those observed in young subjects. These findings raise the question of whether the alterations that can be observed in the immune parameters of the elderly are a cause or a result of underlying disease processes. Moreover, studies on centenarians revealed a remodeling of the immune system rather than a deterioration, suggesting that the changes observed during immunosenescence do not correspond to immunodeficiency. The underlying mechanisms of these events are however still unclear. The purpose of the present review is to assess the status of research on the immunobiology of aging. In this first section, we focus attention on the B cell biology of aging. In clinical practice, the changes in humoral immune responsiveness and antibody-mediated defense mechanisms could greatly influence the incidence and outcome of bacterial infections and autoimmune diseases as well as the response to vaccines.