Radiation oncologist perceptions of therapeutic cannabis use among cancer patients.

INTRODUCTION: Cancer patients are increasingly incorporating medical marijuana into the management of treatment-related side effects. Currently however, data is limited regarding the risks and benefits of therapeutic cannabis for cancer patients. We sought to characterize radiation oncologists' practices and opinions regarding therapeutic cannabis via a nationwide survey. MATERIALS AND METHODS: An anonymous survey was distributed via email to 873 radiation oncologists in the American Society for Radiation Oncology member database. Radiation oncologists were asked their opinions and practices regarding the use of therapeutic cannabis for their patients. Bivariate analyses of potential predictors for responses were conducted using standard statistical techniques. RESULTS: One hundred seven radiation oncologists completed the survey. According to the survey, 36% of respondents would recommend therapeutic cannabis to their patients to mitigate treatment toxicity. Physicians practicing in states where medical marijuana is legal were more likely to recommend it compared to physicians working in states that have not legalized medical marijuana (OR = 3.79, 1.19-12.1, p = 0.01). Seventy-one percent of respondents reported therapeutic cannabis as being effective at least some of the time for managing treatment-related toxicities. Fifty-eight percent of physicians reported lacking sufficient knowledge to advise patients regarding therapeutic cannabis, while 86% of respondents were interested in learning more about therapeutic cannabis for cancer patients. CONCLUSIONS: Although a majority of radiation oncologists believe there are benefits to therapeutic cannabis, many are hesitant to recommend for or against its use. Radiation oncologists appear to be interested in learning more about how therapeutic cannabis may play a role in their patients' care.

Dosimetric comparison of multiple vs single isocenter technique for linear accelerator-based stereotactic radiosurgery: The Importance of the six degree couch.

PURPOSE: Single isocenter technique (SIT) for linear accelerator-based stereotactic radiosurgery (SRS) is feasible. However, SIT introduces the potential for rotational error which can lead to geographical miss. Additional planning treatment volume (PTV) margin is required when using SIT. With the six degrees of freedom (6DoF) couch, rotational error can be minimized. We sought to evaluate the effect of the 6DoF couch on the dosimetry of patients with multiple brain metastases treated with SIT. MATERIALS AND METHODS: Ten consecutive patients treated with SRS to ≥3 metastases were identified. Original treatments had MIT plans (MITP). The lesions were replanned using SIT. Lesions 5-10 cm from isocenter had an additional 1mm of margin. Patients were replanned with these additional margins to account for inability to correct rotational error (SITPM). Multiple dosimetric variables and time metrics were evaluated. Dosimetry planning time (DPT) and patient treatment time (PTT) were evaluated. Statistics were calculated using the Wilcoxon signed-rank test. RESULTS: A total of 73 brain metastases receiving SRS, to a median of 6 lesions per patient, were identified. MITPs treated 73 lesions with 63 isocenters. On average, MITPs had a 19.2% higher brain V12 than SITPs (P = 0.017). For creation of SITPM, 30 lesions required 1 mm of additional margin, while none required 2 mm of margin. This increased V12 by 47.8% on average per patient (P = 0.008) from SITP to SITPM. DPT was 5.5 hours for SITP, while median for MITP was 12.5 hours (P = 0.005) PTT was 30 minutes for SITP, while median for MITP was 144 minutes (P = 0.005). CONCLUSIONS: SITPs are comparable to MITPs if rotational error can be corrected with the use of a 6DoF couch. Increasing margin to account for rotational error leads to a nearly 50% increase in V12, which could result in higher rates of radiation necrosis. Time savings are significant using SIT.

Perception and Utilization of Cannabinoids in Patients Undergoing Radiation Treatment: Our Patients Are Curious.

PURPOSE: Limited studies have described the utilization of cannabinoids among patients with cancer. This survey study aimed to characterize utilization patterns and perceptions of cannabinoid use for treatment-related side effects among patients receiving radiation treatment. METHODS AND MATERIALS: This was an anonymous survey study of patients who were undergoing or recently completed radiation treatment at a comprehensive cancer center. Data on cannabinoid use during cancer treatment, reasons for the use of cannabinoids, perceived effects of cannabinoids, and formulations of usage were collected and summarized using descriptive statistics. RESULTS: Of the 431 respondents, 111 (25.8%) patients reported cannabinoid use since their cancer diagnosis. Among the cannabinoid users, a majority (73.9%) experienced improvement in symptoms; 38.7% had better relief of cancer-treatment symptoms from cannabinoids in comparison to their prescription medications, and 16.2% lowered the amount of prescription pain medications needed after using cannabinoids. Cannabinoids appeared to be most effective in helping patients manage sleep (76.6%) and anxiety (72.1%). When asked about whether physicians should be discussing cannabinoid use, 45.1% of cannabinoid users wanted to speak with their doctors regarding its utilization. For patients who did not report cannabinoid use, a large majority (83.1%) never had discussions with their doctors regarding its utilization as part of their cancer care, and 34.8% wanted to learn more about cannabinoids from their doctors. CONCLUSIONS: About 1 in 4 patients with cancer reported cannabinoid use to assist in symptom control. A majority had subjective alleviation of treatment-related symptoms from cannabinoid use. Regardless of cannabinoid use, a sizable percentage of patients never had any discussions about cannabinoids with their oncologists, with some expressing interest in learning more. Guidelines are needed to assist radiation oncologists on how cannabinoids may play a role in caring for patients.

Age, racial, and ethnic disparities in reported clinical studies involving brachytherapy.

PURPOSE: The purpose of this study was to evaluate for age, racial, and ethnic disparities among clinical studies where patients can potentially receive brachytherapy treatment. METHODS AND MATERIALS: Trials involving brachytherapy for breast, cervical, prostate, and uterine cancers were identified using ClinicalTrials.gov. The age, racial, and ethnic breakdown of the identified trials were compared to US population-estimates derived from the Surveillance, Epidemiology, and End Results (SEER) Program. Primary outcomes were gaps between gaps between mean age and race and ethnic proportions in trials and the US population. Secondary outcomes included proportions of racial and ethnic data reporting. Descriptive statistics, t-tests, χ2 tests, and univariate analysis were used to analyze the data. RESULTS: A total of 77 trials with reported data were identified, representing 13,580 patients. The overall difference in mean age in the identified trials compared to US population estimates was -2.29 years (p < 0.001), with the largest difference occurring in prostate cancer at -2.72 years (p < 0.001). With the exception of ethnicity in cervical cancer (p = 0.18), all racial and ethnic distributions were statistically significantly different. Overall, the largest disparity was among Asian (-2.65%) and Hispanic patients (-1.05%). Of the 77 trials, 76 (98.7%) reported age, 36 (46.8%) reported race, and 24 (31.2%) reported ethnicity. CONCLUSIONS: Diversity data is underreported among clinical studies where brachytherapy is a potential treatment component. However, among reported trials, disparities are present albeit relatively small compared to previous studies reporting on disparities in clinical trials. Future efforts should emphasize increased reporting of racial and ethnicity data as well as ensuring inclusion of older patients and minorities.

Polypharmacy in older adults with cancer undergoing radiotherapy: A review.

Polypharmacy is characterized by the simultaneous use of multiple medications, including prescription drugs, over-the-counter drugs, and nutritional supplements. Polypharmacy is known to increase the risk of adverse drugs reactions, drug-drug interactions, and medication errors, and to negatively impact quality of life. The prevalence of polypharmacy varies by population, but has been reported to exceed 90% among older adults with cancer. Polypharmacy may be exacerbated among older adults with cancer receiving radiation therapy due to the resulting acute or chronic side effects that need to be managed with additional medications. The medications prescribed to manage radiation-related side effects increase the risk of adverse drug events, as do changes in nutritional status related to the secondary side effects of radiation treatment. Side effects from treatment may result in the need for breaks in cancer therapy or treatment delays, which ultimately can lead to worse oncologic outcomes. Few studies have examined polypharmacy in the context of older adults undergoing radiation therapy. We sought to review the literature pertaining to polypharmacy among older adults with cancer and discuss implications specifically for those individuals undergoing radiation therapy. This paper presents a narrative review of studies published in the past decade that provided detailed information on polypharmacy in older adults undergoing radiation therapy for cancer. The review elucidated good practices to avoid adverse drug events from polypharmacy, but more studies are warranted to develop standard guidelines.

Ablative Radiotherapy as a Strategy to Overcome TKI Resistance in EGFR-Mutated NSCLC.

Tyrosine kinase inhibitor (TKI) therapy is the recommended first-line treatment for metastatic non-small-cell lung cancer (NSCLC) positive for epidermal growth factor receptor (EGFR) gene mutation. However, most individuals treated with TKI therapy for EGFR-mutant NSCLC will develop tumor resistance to TKI therapy. Therapeutic strategies to overcome TKI resistance are the topic of several ongoing clinical trials. One potential strategy, which has been explored in numerous trials, is the treatment of progressive sites of disease with stereotactic body radiation treatment (SBRT) or stereotactic radiosurgery (SRS). We sought to review the literature pertaining to the use of local ablative radiation therapy in the setting of acquired resistance to TKI therapy and to discuss stereotactic radiation therapy as a strategy to overcome TKI resistance.

An Updated Review on Head and Neck Cancer Treatment with Radiation Therapy.

The complexity of head and neck cancers (HNC) mandates a multidisciplinary approach and radiation therapy (RT) plays a critical role in the optimal management of patients with HNC, either as frontline or adjuvant treatment postoperatively. The advent of both definitive and post-operative RT has significantly improved the outcomes of patients with HNC. Herein, we discuss the role of postoperative RT in different subtypes of HNC, its side effects, and the importance of surveillance. The treatment regions discussed in this paper are the oral cavity, nasopharynx, paranasal sinus cavity, oropharynx, larynx and hypopharynx. Multiple studies that demonstrate the importance of definitive and/or postoperative RT, which led to an improved outlook of survival for HNC patients will be discussed.

Combination radiation and immunotherapy in gynecologic malignancies-a comprehensive review.

Definitive and adjuvant radiation and chemoradiation have been mainstays in the management of multiple gynecologic malignancies for decades. However, despite these treatments, the prognosis of patients with locally advanced, recurrent, refractory, and metastatic disease continues to be poor. Over the last decade, immune checkpoint inhibitors have emerged as a promising therapeutic modality, but response rates to monotherapy are low. Mounting basic science and translational research suggests that immunotherapy and radiation may act synergistically with the potential to improve clinical outcomes across multiple disease sites relative to monotherapy with either radiation or immunotherapy alone. Results from early clinical trials in other disease sites, and burgeoning trials within the gynecologic malignancies space hold promise for combined modality treatment. With increasing clinical data supporting combined modality therapy, there is interest in reevaluating treatment paradigms in gynecologic malignancies to improve the current standards of care. In this review, current proposed mechanisms, rationale, and evidence for treatment of gynecologic malignancies with combined radiation and immunotherapy, specifically immune checkpoint inhibitors, will be discussed. Additionally, although currently early and limited, existing clinical data will be summarized as it applies to cervical, endometrial, ovarian, and vulvar cancers. The status of current clinical trials investigating the sequencing, dosing, and fractionation of combined radiation and immunotherapy in these disease sites will also be reviewed.

Growth of the Social #RadOnc Network on Twitter.

PURPOSE: Twitter is an increasingly popular social media platform within the health care community. The objective of this analysis is to characterize the profile of radiation oncology-related tweets and Twitter users over the past 6 years. METHODS AND MATERIALS: Using the web-based social media analytics platform Symplur Signals, we filtered tweets containing at least 1 of the following hashtags or key words: #radonc, #radiationoncology, "rad onc," or "radiation oncology." We evaluated radiation oncology-related Twitter activity between October 2014 and March 2020 for tweet frequency, tweet content, and individuals or groups posting tweets. We identified the most influential Twitter users contributing to radiation oncology-related tweets. RESULTS: From 2014 to 2020, the quarterly volume of radiation oncology-related tweets increased from 5027 to 29,763. Physicians contributed the largest growth in tweet volume. Academic radiation oncologists comprise 60% of the most influential Twitter accounts responsible for radiation oncology-related content. The number of radiation-oncology resident physicians on Twitter increased from 25 to 328 over the past 6 years, and 20% of radiation-oncology residency programs have a Twitter account. Seventy-one percent of radiation oncology-related tweets generated direct communication via mentions, and 59% of tweets contain links to external sources, including scientific articles. CONCLUSIONS: The number of physicians contributing radiation oncology-related Twitter content has increased significantly in recent years. Academic radiation oncologists are the primary influencers of radiation oncology-related Twitter activity. Twitter is used by radiation oncologists to both professionally network and discuss findings related to the field. There remains the opportunity for radiation oncologists to broaden their audience on Twitter to encompass a more diverse community, including patients.

Setup Accuracy in Craniospinal Irradiation: Implications for Planning Treatment Volume Margins.

PURPOSE: Craniospinal irradiation (CSI) using tomotherapy has advantages over standard 3-dimensional techniques. However, there is a paucity of published data on craniospinal setup reproducibility to guide appropriate planning treatment volume (PTV) margins. We sought to evaluate the setup accuracy of patients undergoing CSI to optimize PTV margins. METHODS AND MATERIALS: We measured residual setup deviation between simulation computed tomography (CT) and daily megavoltage CT after couch shifts made by therapists after megavoltage CT-based image registration for 10 patients who completed CSI at our institution. Translational displacement values were recorded at the sella, top of T1, and top of L5 in the anteroposterior (AP) and lateral planes. Systematic and random error were calculated from displacement values. Using z score analysis, we calculated minimal PTV margins to encompass 90% of recorded fractions at each level. We evaluated whether patient characteristics predict for increased setup error using standard statistical techniques. RESULTS: The mean setup deviation in the AP plane across all treatments was 2.49, 3.40, and 3.83 mm at the sella, T1, and L5, respectively. Mean lateral setup error was 2.86, 4.02, and 5.46 mm at the sella, T1, and L5, respectively. Systematic error ranged from 0.75 to 1.01 mm at the sella, 1.09 to 1.37 mm at T1, and 1.30 to 1.50 mm at L5. Random error ranged from 1.35 to 1.41 mm at the sella, 1.48 to 1.73 mm at T1, and 2.26 to 2.37 mm at L5. The minimum margin to cover 90% of the treatments was 6.4, 8.2, and 10.5 mm at the sella, T1, and L5, respectively. There appeared to be a correlation between older age and lateral setup error in the L spine approaching statistical significance (R, 0.629; P = .052). CONCLUSIONS: Setup error increases in the caudal direction of the spine and is greater in the lateral plane compared with the AP plane. We recommend a PTV margin of 5 to 7 mm in the brain and 10 mm in the spine.

Myosin V attachment to cargo requires the tight association of two functional subdomains.

The myosin V carboxyl-terminal globular tail domain is essential for the attachment of myosin V to all known cargoes. Previously, the globular tail was viewed as a single, functional entity. Here, we show that the globular tail of the yeast myosin Va homologue, Myo2p, contains two structural subdomains that have distinct functions, namely, vacuole-specific and secretory vesicle-specific movement. Biochemical and genetic analyses demonstrate that subdomain I tightly associates with subdomain II, and that the interaction does not require additional proteins. Importantly, although neither subdomain alone is functional, simultaneous expression of the separate subdomains produces a functional complex in vivo. Our results suggest a model whereby intramolecular interactions between the globular tail subdomains help to coordinate the transport of multiple distinct cargoes by myosin V.

Patterns of care and treatment outcomes in patients age 80 or older with non-metastatic pancreatic cancer.

INTRODUCTION: Older adults are underrepresented in landmark trials that determine treatment guidelines for pancreatic cancer. We used the National Cancer Database (NCDB) to compare treatment patterns and outcomes in stage I-III pancreatic cancer between older adult patients, defined as age 80 or older, to patients younger than 80. MATERIAL AND METHODS: We identified 140,678 patients in the NCDB diagnosed with pancreatic cancer from 2004 to 2015. Patients with metastatic disease or non-adenocarcinoma histologies were excluded. Descriptive statistics comparing patients age 80+ and age <80 were generated. Logistic regression was used to evaluate predictors of cancer-directed therapy receipt (defined as receipt of chemotherapy, radiation, or surgery) in older patients, and Cox proportional hazards modeling was performed to evaluate survival in the older cohort. RESULTS: We identified 140,678 patients with non-metastatic pancreatic cancer, of which 23,395 patients (16.6%) were 80 or older. Among older patients, 44.5% of patients received cancer-directed therapy compared to 78.7% among other patients (p < .001). Older patients had worse 2-year survival at 11.3% versus 27.5% for younger (p < .001). 2-year survivorship decreased further in older patients who received no cancer-directed treatment, at 4.7% compared with 19.5% for older patients receiving treatment (p < .001). After propensity score matching, cancer-directed treatment remained associated with improved survival for older patients (hazard ratio 0.42; 95% confidence interval 0.41-0.43; p < .001). DISCUSSION: Rates of cancer-directed therapy were low in patients age 80+, with 55.5% receiving no therapy. Cancer-directed treatment was associated with an overall survival benefit. Future trials are needed to define optimal treatment paradigms in this population.

Temporal Trends of Resident Experience in External Beam Radiation Therapy Cases: Analysis of ACGME Case Logs from 2007 to 2018.

PURPOSE: We sought to characterize temporal trends of radiation oncology resident-reported external beam radiation therapy (EBRT) case experience with respect to various disease sites, including trends in stereotactic radiosurgery and stereotactic body radiation therapy cases. METHODS AND MATERIALS: Summarized, deidentified case logs for graduating radiation oncology residents between 2007 and 2018 were obtained from the Accreditation Council for Graduate Medical Education national summary data report. Mean number of cumulative cases and standard deviations per graduating resident by year were evaluated. Cases were subdivided into 12 disease-site categories using the Accreditation Council for Graduate Medical Education classification. Analysis of variance was used to determine significant differences, and strength of association was evaluated using Pearson correlation. RESULTS: The number of graduating residents per year increased by 66% from 114 in 2007 to 189 in 2018 (P < .001, r = 0.88). The overall mean number of EBRT cases per graduating resident decreased by 13.2% from 521.9 in 2007 to 478.5 in 2018, with a decrease in the ratio of nonmetastatic to metastatic cases per graduating resident. There was significant variation among the disease categories analyzed; however, the largest proportionate decreases were seen in hematologic, lung, and genitourinary malignancies. Stereotactic radiosurgery volume per graduating resident increased from an average of 27.9 cases in 2007 to 50.3 in 2018 (P < .001, r = 0.96). Stereotactic body radiation therapy volume per graduating resident increased as well, from a mean of 6 cases in 2007 to 55.6 cases in 2018 (P < .001, r = 0.99). CONCLUSIONS: We report a longitudinal summary of resident-reported experience in EBRT cases. These findings have implications for future efforts to optimize residency training programs and requirements.

Identification of an organelle-specific myosin V receptor.

Class V myosins are widely distributed among diverse organisms and move cargo along actin filaments. Some myosin Vs move multiple types of cargo, where the timing of movement and the destinations of selected cargoes are unique. Here, we report the discovery of an organelle-specific myosin V receptor. Vac17p, a novel protein, is a component of the vacuole-specific receptor for Myo2p, a Saccharomyces cerevisiae myosin V. Vac17p interacts with the Myo2p cargo-binding domain, but not with vacuole inheritance-defective myo2 mutants that have single amino acid changes within this region. Moreover, a region of the Myo2p tail required specifically for secretory vesicle transport is neither required for vacuole inheritance nor for Vac17p-Myo2p interactions. Vac17p is localized on the vacuole membrane, and vacuole-associated Myo2p increases in proportion with an increase in Vac17p. Furthermore, Vac17p is not required for movement of other cargo moved by Myo2p. These findings demonstrate that Vac17p is a component of a vacuole-specific receptor for Myo2p. Organelle-specific receptors such as Vac17p provide a mechanism whereby a single type of myosin V can move diverse cargoes to distinct destinations at different times.

Quantum dots for live cell and in vivo imaging.

In the past few decades, technology has made immeasurable strides to enable visualization, identification, and quantitation in biological systems. Many of these technological advancements are occurring on the nanometer scale, where multiple scientific disciplines are combining to create new materials with enhanced properties. The integration of inorganic synthetic methods with a size reduction to the nano-scale has lead to the creation of a new class of optical reporters, called quantum dots. These semiconductor quantum dot nanocrystals have emerged as an alternative to organic dyes and fluorescent proteins, and are brighter and more stable against photobleaching than standard fluorescent indicators. Quantum dots have tunable optical properties that have proved useful in a wide range of applications from multiplexed analysis such as DNA detection and cell sorting and tracking, to most recently demonstrating promise for in vivo imaging and diagnostics. This review provides an in-depth discussion of past, present, and future trends in quantum dot use with an emphasis on in vivo imaging and its related applications.

The evolving role of radiation therapy for resectable and unresectable gastric cancer.

Gastric cancer is a common malignancy worldwide, and treatment of localized disease has shifted from surgery alone to the addition of chemotherapy at various stages in treatment. The role of radiation in the management of gastric cancer has evolved significantly since the seminal publication of INT 0116 demonstrated a survival advantage to adjuvant chemoradiation. In this review, we summarize multiple landmark studies discussing the role of radiation in non-metastatic gastric cancer, both in resectable and unresectable patients. This review will additionally discuss the evidence for pre-operative chemoradiation, as the benefit has already been demonstrated in esophageal and rectal cancer.

Induction of the Abscopal Effect with Immunotherapy and Palliative Radiation in Metastatic Head and Neck Squamous Cell Carcinoma: A Case Report and Review of the Literature.

The induction of the abscopal effect using immunotherapy and radiation is under investigation through case reports and institutional studies. We describe a case of the abscopal effect with a combination of ipilimumab, nivolumab, and palliative radiation, in a patient with metastatic head and neck squamous cell carcinoma (mHNSCC).

Tumor Control and Toxicity after SBRT for Ultracentral, Central, and Paramediastinal Lung Tumors.

PURPOSE: Increased rates of toxicity have been described after stereotactic body radiation therapy (SBRT) for central lung tumors within 2 cm of the proximal bronchial tree (PBT). Recent studies have defined a new class of ultracentral tumors. We report our experience treating ultracentral, central, and paramediastinal tumors with SBRT and compare toxicity, disease control, and survival rates. METHODS AND MATERIALS: We reviewed the records of patients with central lung tumors treated with SBRT between September 2009 and July 2017. Tumors were classified as central if within 2 cm of the PBT, ultracentral if the planning target volume touched the PBT or esophagus, and paramediastinal if touching mediastinal pleura. Actuarial rates of grades 2+ and 3+ toxicity, local control (LC), and overall survival were assessed using the Kaplan-Meier method and compared using a log-rank test. Toxicity was scored with the Common Terminology Criteria for Adverse Events, version 4.03. RESULTS: We identified 68 patients with 69 central lung tumors, including 14 ultracentral, 15 paramediastinal, and 39 central tumors. Fifty-three patients were treated for early stage lung cancer and 15 for lung metastases. The prescribed dose ranged from 40 Gy to 60 Gy over 3 to 8 fractions. Most patients were treated using 5 fractions (83%), followed by 8 fractions (10%). Median follow-up was 19.7 months (range, 3.3-78.3 months). The 2-year estimates of LC (89%, 85%, and 93%, respectively; P = .72) and overall survival (76%, 73%, and 72%, respectively; P = .75) for ultracentral, central, and paramediastinal tumors were similar. Ultracentral tumors had an increased risk of grade 2+ toxicity (57.6% vs 14.2% vs 7.1%; P = .007) at 2 years. One patient with an ultracentral tumor developed grade 5 respiratory failure. CONCLUSIONS: The oncologic outcomes after SBRT for ultracentral, central, and paramediastinal lung tumors were similar, with LC exceeding 85% at 2 years using predominantly 5-fraction schedules. Ultracentral lung tumors were associated with an increased risk of toxicity in our patient cohort. Additional studies are needed to minimize toxicity for ultracentral tumors.

Continuous hemoglobin monitoring in pediatric trauma patients with solid organ injury.

BACKGROUND/PURPOSE: Hemoglobin monitoring is required in pediatric trauma patients with solid organ injury. We hypothesized that noninvasive hemodynamic monitoring (NIHM) represents an effective, safe alternative to laboratory hemoglobin (LabHb) monitoring in clinically stable patients. METHODS: A retrospective cohort study was conducted regarding pediatric trauma patients (<18 years old) with blunt solid organ injury over six consecutive months. Continuous NIHM was initiated at the time of admission, and LabHb measurements were obtained per institutional guidelines. Measurements were correlated within two hours of assessment and patient outcomes were analyzed. RESULTS: Twenty-one patients met inclusion criteria and had evaluable data. Blunt trauma was the exclusive mechanism of injury, and mean injury severity score was 16.6 for the cohort. Bland Altman analysis showed an average deviation of 0.80 g/dL between NIHM and LabHb values for all data pairs. Measurement trends were highly correlated in patients with stable hemoglobin levels and those requiring blood transfusion. CONCLUSIONS: NIHM demonstrated clinically acceptable accuracy when following hemoglobin trends in the defined pediatric trauma patient population. Slight variances between NIHM and LabHb values were occasionally noted, but did not affect clinical management. Continuous NIHM represents a potentially valuable adjunct to traditional laboratory hemoglobin monitoring. LEVEL OF EVIDENCE RATING: IV.