Head Exposure Research Articles

The head of invasive cardiologists as a target of professional exposure to ionizing radiation

Exposure to ionizing radiation has recognized detrimental cancer and non-cancer health effects. These effects are now well-proven not only for high doses > 1,000 millisieverts (mSv) associated with head radiotherapy but also for moderate (100–1,000 mSv) and even low (< 100 mSv) doses, of interest for professionally exposed cardiologists. The head of interventional cardiologists is highly exposed to ionizing radiation, with possible damage to the eye and brain. Unprotected interventional cardiologists experience head radiation doses up to ten times greater than chest doses below lead aprons, with marked exposure to the left hemisphere of the brain reaching up to 2 Sv—equivalent to 10,000 chest X-rays over a professional lifetime. This narrative review aims to provide an overview of the background of radioprotection, the biological mechanisms involved, and the epidemiological evidence regarding the health effects of head exposure to ionizing radiation in invasive cardiologists. These health effects include cataracts, brain cancer, cerebrovascular diseases, neurodegeneration, and mood disorders. The evidence gathered from other exposed populations, which experienced similar eye and brain doses, has also been reviewed. This is important because the doses, risks, and effects are consistent in cases of repeated exposures, which occur more frequently for patients, and in situations involving chronic low doses, as seen with interventional cardiologists. Despite these risks, effective protective measures—such as suspended lead ceilings, curtains, and specialized eyewear—can reduce radiation exposure to near-zero levels. In some fields, like interventional cardiac electrophysiology, a groundbreaking near-zero radiation approach using non-fluoroscopic methods has been created, eliminating radiation exposure and alleviating orthopedic stress and operational discomfort. The race to zero radiation in interventional cardiology is ongoing.

Evaluation of the RF depositions at 3T in routine clinical scans with respect to the SAR safety to improve efficiency of MRI utilization.

This study explores the potential for improving of 3T MRI utilization by assessing and tailoring RF exposure in routine clinical scans while complying to standard safety limit. Using two generic human body models, we evaluated pbSAR10g values at four landmark positions (knee, pelvis, thoracic spine, head) at different wbSAR levels. Specifically, weanalyzed local SAR10g in different operating modes and computed the maximum safety wbSAR, ensuring compliance with IEC limits. In normal operating mode, the RF power deposition reached wbSAR limit before the pbSAR10g limit. In the first level controlled operating mode, pbSAR10g limit is reached before the wbSAR limit in the knee, thoracic spine scanning scenarios, while the wbSAR limit is reached first in the pelvis scanning scenarios, making it the most potential-releasing (up to 33.33 %) scanning scenario. For head exposure, the head SAR10g limit is reached before the wbSAR limit, highlighting the necessity for strict SAR control. Moreover, we calculated the minimum allowable TR for common imaging sequences for reference. Different RF exposure setups are necessary to meet safety standards in various scenarios. By implementing careful RF exposure setups in routine clinical scans, the high potential capacity of 3T MRI can be fully released.

Effect of impact kinematic filters on brain strain responses in contact sports.

Impact kinematics are widely employed to investigate mechanisms of traumatic brain injury (TBI). However, they are susceptible to noise and artefacts; thus, require data filtering. Few studies have focused on how data filtering affects brain strain most relevant to TBI. Here, we report that impact-induced brain strains are much less sensitive to data filtering than kinematics based on three filtering methods: CFC180, lowpass 200Hz, and a new method called Head Exposure to Acceleration Database in Sport (HEADSport). Using mouthguard-measured head impacts in elite rugby (N=5694), average Euclidean distances between the three filtered angular velocity profiles and their unfiltered counterparts are used to identify three groups of impacts with large variations: 90-95th, 95-99th, and >99th percentile. From each group, 20 impacts are randomly selected for simulation using the anisotropic Worcester Head Injury Model (WHIM) V1.0. HEADSport and CFC180 are the most and least effective, respectively, in suppressing "unphysical artefacts" shown as sharp spikes with a rather short impulse duration (e.g., <3 ms) in angular velocity. However, maximum principal strain (MPS), especially that in the corpus callosum, is much less sensitive to data filtering compared to kinematic peaks (e.g., reduction of 3% vs. 47% and 90% for peak angular velocity and acceleration with HEADSport for impacts of >99th percentile). These findings confirm that the brain acts as a low-pass filter, itself, to suppress high frequency noise in impact kinematics. Therefore, brain strain can serve as a common metric for TBI biomechanical studies to maximize relevance to the injury, as it is not sensitive to kinematic filters.

Cystoductojejunostomy for pseudocyst associated with chronic pancreatitis

Pseudocyst is frequently associated with chronic pancreatitis (CP). We describe our experience of managing seven patients for pseudocyst associated with CP by bile duct preserving pancreatic head resection (BDPPHR) and cystoductojejunostomy. 88 patients were operated on for chronic pancreatitis between April 2021 till May 2023 out of which 7 patients underwent BDPPHR and cystoductojejunostomy for pseudocyst associated with CP. Key steps of surgery include meticulous dissection with exposure of the pancreatic head to tail, head excision up to the posterior capsule with laying open of the pancreatic duct till the tail and reconstruction incorporating pancreatic duct (PD) and pseudocyst to a single loop of jejunum. All seven patients were successfully treated with BDPPHR and cystoductojejunostomy. Mean operative time and mean blood loss was 478 minutes and 450 ml respectively. Mean hospital stay was 4.5 days. On follow-up at a one-year minimum, all patients had complete pain relief. In patients with pseudocyst associated with CP, surgery preferably needs to address both the pseudocyst and the underlying chronic pancreatitis to improve the quality of life. A combined anastomosis to the PD and cyst may be termed as cystoductojejunostomy.

The supinator approach to the lateral elbow: a technique description and literature review

We present the supinator approach for management of the lateral elbow which combines the principal features of the Kocher and Kaplan approaches. The Kaplan interval is connected to the Kocher interval by a transverse incision extending to the supinator crest. The supinator approach maintains a safe distance from the posterior interosseous nerve and is likely to avoid the insertional variations of the LUCL. In our experience, the supinator approach is reproducible, provides ample exposure of the radial head and lateral elbow and reduces the risk of instability and neurologic insult.

The effects of radiofrequency electromagnetic fields exposure on human self-reported symptoms: A systematic review of human experimental studies

BackgroundThe technological applications of radiofrequency electromagnetic fields (RF-EMF) have been steadily increasing since the 1950s exposing large proportions of the population. The World Health Organization (WHO) is assessing the potential health effects of exposure to RF-EMF. ObjectivesTo systematically assess the effects of exposure to RF-EMF on self-reported non-specific symptoms in human subjects and to assess the accuracy of perceptions of presence or absence of RF-EMF exposure. MethodsEligibility criteria: experimental studies carried out in the general population and in individuals with idiopathic environmental intolerance attributed to EMF (IEI-EMF), in any language.Information sources: Medline, Web of Science, PsycInfo, Cochrane Library, Epistemonikos, Embase and EMF portal, searched till April 2022.Risk of Bias (ROB): we used the RoB tool developed by OHAT adapted to the topic of this review.Synthesis of results: we synthesized studies using random effects meta-analysis and sensitivity analyses, where appropriate. ResultsIncluded studies: 41 studies were included, mostly cross over trials and from Europe, with a total of 2,874 participants.Synthesis of results: considering the primary outcomes, we carried out meta-analyses of 10 exposure-outcomes pairs. All evidence suggested no or small non-significant effects of exposure on symptoms with high (three comparisons), moderate (four comparisons), low (one comparison) and very low (two comparisons) certainty of evidence. The effects (standard mean difference, where positive values indicate presence of symptom being exposed) in the general population for head exposure were (95% confidence intervals) 0.08 (−0.07 to 0.22) for headache, −0.01 (−0.22 to 0.20) for sleeping disturbances and 0.13 (−0.51 to 0.76) for composite symptoms; and for whole-body exposure: 0.09 (−0.35 to 0.54), 0.00 (−0.15 to 0.15) for sleeping disturbances and −0.05 (−0.17 to 0.07) for composite symptoms. For IEI-EMF individuals SMD ranged from −0.19 to 0.11, all of them with confidence intervals crossing the value of zero.Further, the available evidence suggested that study volunteers could not perceive the EMF exposure status better than what is expected by chance and that IEI-EMF individuals could not determine EMF conditions better than the general population. DiscussionLimitations of evidence: experimental conditions are substantially different from real-life situations in the duration, frequency, distance and position of the exposure. Most studies were conducted in young, healthy volunteers, who might be more resilient to RF-EMF than the general population. The outcomes of interest in this systematic review were symptoms, which are self-reported. The available information did not allow to assess the potential effects of exposures beyond acute exposure and in elderly or in chronically ill people. It cannot be ruled out that a real EMF effect in IEI-EMF groups is masked by a mix with insensitive subjects. However, studies on symptoms reporting and/or field perceptions did not find any evidence that there were particularly vulnerable individuals in the IEI-EMF group, although in open provocation studies, when volunteers were informed about the presence or absence of EMF exposure, such differences were consistently observed.Interpretation: available evidence suggests that acute RF-EMF below regulatory limits does not cause symptoms and corresponding claims in the everyday life are related to perceived and not to real EMF exposure status.

Prevalence of skin diseases among hostellers attending the tertiary care hospital

Background: Skin diseases are more common but are mostly non-fatal and chronic. Dermatological conditions account for a significant proportion of the global burden of diseases. Aims and Objectives: The study aimed to determine the prevalence of skin diseases among hostellers, determine the causative factors, and describe the prevention. Materials and Methods: This cross-sectional study was conducted for 2 months in the outpatient Department of Dermatology, Government Medical College, Pudukottai, on 507 hostellers. The study subjects were examined and diagnosed by the dermatologist. Questions such as exposure to sunlight, usage of sunscreen, frequency of head baths, and junk food consumption were asked and recorded in a case study form by the principal investigator. Results: Pityriasis capitis was the most prevalent skin disease among 507 participants, followed by acne vulgaris (54.83%) and pediculosis capitis (25.64%). Pityriasis capitis is more common in men (56.17%), with higher chances in those with head baths (&lt;3 times/week) and exposure to sunlight (28.08%). Acne vulgaris affects both males and females equally; face washing &lt;3 times daily is associated with oil and sebum retention, while lack of sunscreen and junk food intake are linked. Periorbital melanosis is more prevalent in females (54.62%) and is linked to stress (66.39%). Sleep duration is also a factor, with 69.23% of girls having a history of cosmetic usage. Conclusion: Pityriasis capitis, acne vulgaris, pediculosis capitis, dermatophytosis, and periorbital melanosis are common skin diseases caused by sharing, sleep deprivation, stress, and poor hygiene. Proper hygiene, sleep patterns, and self-care can reduce skin disease incidence.

Air pollution is associated with increased incidence-rate of head and neck cancers: A nationally representative ecological study

IntroductionEarly studies show conflicting findings regarding particulate matter ≤ 2.5 μm in diameter (PM2.5) exposure and development of head and neck cancers (HNC). We analyzed the relationship between PM2.5 exposure and various types of HNC in a nationally representative ecological sample. MethodsWe determined HNC incidence in 608 US counties from 2011 to 2019 using the Surveillance, Epidemiology and End Results (SEER) Program from the National Cancer Institute. We also collected information on sociodemographic factors from SEER and data on smoking and alcohol intake from CDC data frames (county level). PM2.5 exposure levels were estimated using satellite and meteorological data via previously validated general additive models. Flexible semi-nonparametric regression models were used to test the relationship between PM2.5 exposure levels and HNC incidence, adjusting for demographics, socioeconomic factors, and comorbidity. ResultsIncreased PM2.5 exposure levels were associated with higher incidence-rates of oral cavity and pharyngeal cancers controlling for confounders in our primary analyses (IRR = 1.04, 95 % CI 1.01, 1.07, p = 0.02 per 1 μg/m3 increase in PM2.5). This relationship was maintained after adjusting for multiple testing (Holm s method, p = 0.04) and in ordinary least squares (OLS) regression (β = 0.17, 95 % CI 0.01, 0.57, p = 0.01). Increased exposure was also associated with other HNC: esophagus (IRR = 1.06, 95 % CI 1.01, 1.11, p = 0.02), lip (IRR = 1.16, 95 % CI 1.03, 1.31, p = 0.01), tonsil (IRR = 1.10, 95 % CI 1.03, 1.16, p < 0.01). However, these relationships were not maintained in secondary analyses. ConclusionsThis nationally representative ecological study shows that increased levels of air pollution are associated with increased incidence of overall oral cavity and pharyngeal cancers in the US.

CT-guided core needle biopsies of head and neck tumors: a comprehensive monocenter analysis of safety and outcomes.

Although core needle biopsy is an important tool in minimally invasive tissue sampling and diagnostics for head and neck masses, comprehensive data about safety and outcomes is lacking. To retrospectively evaluate the diagnostic performance and safety of computed tomography (CT)-guided percutaneous core needle biopsy of head and neck masses. This retrospective single-center study included patients from 04/2007 to 12/2021, and a total of 156 core needle biopsies were evaluated. The initial histopathological results were compared with the long-term final diagnosis to evaluate the diagnostic yield of CT-guided core needle biopsies. The patients' age, sex, and history of malignancy, as well as procedural complications and radiation exposure were collected. A total of 156 biopsies of 150 patients (mean age 56years ± 17; 89 men) were evaluated. 57.3% (86/150) of patients had a history of malignancy. 55.1% (86/156) of the lesions were accessed by an infrahyoid needle approach. 92.9% (145/156) of biopsies yielded conclusive results. There were no false positives and 4 false negatives, resulting in a total false negative rate of 2.7% (4/145) and a total diagnostic yield of 90.4% (141/156). There were nine puncture-related complications (9/156-5.7%). None of the complications required further reintervention. The average dose length product was 311.3mGy × cm. CT-guided core needle biopsies of head and neck masses showed excellent results with high diagnostic yield and clinical safety. General anesthesia for open biopsy carries a higher risk for elderly patients, and fine needle aspiration has a poor reputation in terms of its diagnostic yield. This study focuses on safety and diagnostic yield of CT-guided core needle biopsies. • CT-guided core needle biopsy in head and neck tumors was a reliable and safe procedure. • The most common cause for an inconclusive biopsy result was a shortage of tissue collected during the biopsy. • During our study period of nearly 15years, the radiation exposure of head and neck biopsies decreased.

Head Exposure to Acceleration Database in Sport (HEADSport): a kinematic signal processing method to enable instrumented mouthguard (iMG) field-based inter-study comparisons

ObjectiveInstrumented mouthguard (iMG) systems use different signal processing approaches limiting field-based inter-study comparisons, especially when artefacts are present in the signal. The objective of this study was to assess the...

Preliminary Head-Supported Mass Performance Guidance forDismounted Soldier Environments.

The helmet is an ideal platform to mount technology that gives U.S. Soldiers an advantage over the enemy; the total system is recognized quantitatively as head-supported mass (HSM). The stress placed on the head and neck is magnified by adding mass and increasing the center of mass offset away from the atlanto-occipital complex, the head's pivot point on the spine. Previous research has focused on HSM-related spinal degeneration and performance decrement in mounted environments. The increased capabilities and protection provided by helmet systems for dismounted Soldiers have made it necessary to determine the boundaries of HSM and center of mass offset unique to dismounted operations. A human subject volunteer study was conducted to characterize the head and neck exposures and assess the impact of HSM on performance in a simulated field-dismounted operating environment. Data were analyzed from 21 subjects who completed the Load Effects Assessment Program-Army obstacle course at Fort Benning, GA, while wearing three different experimental HSM configurations. Four variable groups (physiologic/biomechanical, performance, kinematic, and subjective) were evaluated as performance assessments. Weight moments (WMs) corresponding to specific performance decrement levels were calculated using the quantitative relationships developed between each metric and the study HSM configurations. Data collected were used to develop the performance decrement HSM threshold criteria based on an average of 10% total performance decrement of dismounted Soldier performance responses. A WM of 134 N-cm about the atlanto-occipital complex was determined as the preliminary threshold criteria for an average of 10% total performance decrement. A WM of 164 N-cm was calculated for a corresponding 25% average total performance decrement. The presented work is the first of its kind specifically for dismounted Soldiers. Research is underway to validate these limits and develop dismounted injury risk guidance.

Influence of patient head definition on induced E-fields during MR examination.

Radiofrequency (RF) exposure during MR examination is limited by IEC 60601-2-33 to prevent thermal hazards to patients. These limits are also the basis to derive the maximum induced field for the demonstration of MR safety of implants per ISO/TS 10974 (2018). One limit is the head-averaged specific absorption rate (SAR), for which the head extent is defined differently by MR and implant vendors. The purpose of this technical note is to inform MR safety stakeholders on the sensitivity of safety evaluations due to different head extent definitions. RF distributions from the validated MRIxViP exposure libraries of 12 high-resolution human anatomical models were scaled to the normative SAR limits for different definitions of the head extent to compare the corresponding induced SAR and electric (E-)field levels. The definitions of the head extent used by major implant vendors and defined in ISO/TS 10974 (2018) are larger than those introduced in IEC 60601-2-33 (2022), resulting in lower RF head exposure by up to 2.4 dB (factor 1.7). Other proposed definitions of the head result in intermediate values. The different head extents result in different maximum RF exposures affecting the risk assessment by up to a factor of 1.7. The results of this study can be used to estimate the additional uncertainty in safety assessments. Future revisions of MR standards should eliminate this inconsistency.

Antegrade Fixation of Distal Metaphyseal Ulnar Shortening Osteotomy.

The ulnar shortening osteotomy (USO) is a common procedure used to treat ulnar impaction syndrome secondary to static or dynamic ulnar-positive variance. There are many described techniques for the USO. The distal metaphyseal ulnar shortening osteotomy (DMUSO) with retrograde cannulated screw fixation was described to reduce complications seen with other techniques. Biomechanical analysis of fixation constructs demonstrates 2-screw constructs are significantly stiffer than 1 screw and antegrade constructs have similar or greater stiffness when compared with retrograde constructs. Here, we describe a technique of antegrade cannulated screw fixation for DMUSO that obviates the need for the disruption of the distal radioulnar joint for intra-articular exposure of the ulnar head. Similar to the traditional retrograde DMUSO technique, this construct may also decrease the risk of delayed union, symptomatic implants associated with diaphyseal osteotomies, and disruption of triangular fibrocartilaginous complex in wafer procedures.

Progress and prospect of clinical application of anti-rabies virus monoclonal antibody preparation

Rabies is a severe infectious disease caused by the rabies virus, which seriously damages the central nervous system. Once it occurs, the fatality rate is close to 100%. The World Health Organization's position paper on rabies vaccines recognizes that rabies immunoglobulin (RIG) should be used for post-exposure prophylaxis (PEP) in all category Ⅲ exposure for the first time, as well as in category Ⅱ exposure that suffer from severe immune deficiency, long-term massive use of immunosuppressants, and head and face exposure. The anti-rabies virus monoclonal antibody has high purity and specific activity, can be produced on a sustainable scale, and has no risk of blood source virus contamination. Preclinical pharmacodynamic studies and clinical trial results of the anti-rabies virus monoclonal antibody preparation have confirmed that the preparation has a broad-spectrum neutralization effect on the rabies virus. Additionally, its combined application with the vaccine has little impact on the active immunity of the vaccine. Therefore, the anti-rabies virus monoclonal antibody preparation shows great potential for clinical application in PEP.

Impact of Power-Line Communication Radiation on Human Health

The advent of smart electrical grids (Smart-grids) has created the need for a reliable communication system within traditional electrical grids. Many technologies are available on the market for communication in smart-grids environment. Communication using PLC (Power-Line Communication or power-line carrier) technology is by far the best choice for operators of these smart-grids, because it uses the electrical cables already in place as a communication link. Unfortunately, since the electrical grid (frequency = 50/60 Hz) was not designed for the transport of high-frequency signals, in PLC mode (100 kHz - 30 MHz) the electrical cables behave like antennas and emit electromagnetic radiation in the nearby environment. This work is a contribution in the evaluation of electromagnetic radiation impact of PLC technology on human health. According to ICNIRP (International Commission for Non-Ionizing Radiation Protection), this type of assessment in done base on SAR (Specific Absorption Rate) and ∆T (tissue temperature raising during exposure to radiation). PLC cables radiation SAR and ∆T are confront with ICNIRP-limits (Guidelines). In order to cover many exposure scenario, interaction between the radiation of an Outdoor-PLC cable and a human head have been analyze using analytical approach (Maxwell equations) and numerical approach (simulation with Feko software). These analyses have demonstrated that exposure to Outdoor-PLC cable electromagnetic radiation is not harmful to human being. For a long-term exposure of human head to PLC cable electromagnetic radiation, The SAR is less than 1nW/Kg and ∆T under 10-5 °C (Far from ICNIRP limits). Analyses have also produce a simplified expression of PLC cable electromagnetic radiation SAR base on Biot-&amp;-Savart law.

Safety Assessment and Uncertainty Quantification of Electromagnetic Radiation from Mobile Phones to the Human Head

With the rapid development of the mobile communication technology, the design of mobile phones has become more complex, and research on the electromagnetic radiation from mobile phones that reaches the human head has become important. Therefore, first of all, a model of mobile phone daily use was established. Then, based on the established simulation model, the safety of human head exposure to mobile phones was evaluated. The generalized polynomial chaos (gPC) method was used to establish a proxy model of the specific absorption rate (SAR) of the human head at different frequencies to perform a parameter uncertainty quantification (UQ). Finally, the Sobol method was used to quantify the influence of relevant variables on the SAR. The simulation results showed that the gPC method can save time and cost while ensuring accuracy, and the SAR value is greatly influenced by the electromagnetic materials of the mobile phone shell. Combined with the above analysis, this paper can provide reasonable suggestions for the design of mobile phone electromagnetic materials.

Hair and Hat Ritual Shaming Punishments in Nineteenth-Century Iran

Abstract This article considers three temporary and reversible penal shaming acts in nineteenth-century Iran: the shaving or cutting of hair, irrespective of gender; the shaving or cutting of men's facial hair; and the forcible removal of headgear or the coerced wearing of silly headgear. Drawing on anthropological, historical, and sociological studies of hair, this study argues that hair and hat punishments embodied elements of ritual, sexuality, social control, and marginalization. In order to understand the meaning of these penal acts, the article looks at general taboos around hair and head exposure alongside licit and voluntary forms of cutting or shaving hair. Illicit sex, heresy, and alcohol consumption were recurring moral crimes most often associated with such forms of humiliating punishment. Since restoration of honor was not the sole prerogative of the government, these punishments were often carried out by those acting on behalf of a religious authority or individually and collectively by ordinary subjects outraged by a moral violation.

222 nm Far-UVC from filtered Krypton-Chloride excimer lamps does not cause eye irritation when deployed in a simulated office environment.

Far-UVC, from filtered Krypton-Chloride lamps, is promising for reducing airborne transmission of disease. While significant research has been undertaken to investigate skin safety of these lamps, less work has been undertaken on eye safety. There is limited data on human eye safety or discomfort from the deployment of this germicidal technology. In this pilot study, immediate and delayed eye discomfort were assessed in a simulated office environment with deployment of Krypton-Chloride lamps, located on the ceiling and directed downwards into the occupied room. Discomfort was assessed immediately postexposure and several days after exposure using validated, Standard Patient Evaluation Eye Dryness (SPEED) and Ocular Surface Disease Index (OSDI) questionnaires. Our results show no significant eye discomfort or adverse effects from the deployment of Far-UVC in this simulated office environment, even when lamps were operated continuously with participants receiving head exposures of up to 50 mJ cm-2 . In addition, a statistically significant reduction in bacteria and fungi of 52% was observed. Far-UVC in this simulated office environment did not cause any clinically significant eye discomfort and was effective at reducing pathogens in the room. These results contribute an important step to further investigation of the interaction of Far-UVC with the human eye.

ODP446 Where's the Nodule?: Atypical Presentation of an Occult Metastatic Papillary Thryoid Carcinoma

Abstract Papillary thyroid Carcinoma (PTC) with apparent distant metastasis but lacking a primary thyroid cancer on pre-operative ultrasonographic examination, is referred by some as occult PTC. In most cases, primary carcinomas are identified after careful pathologic examination of the specimen but in some rare cases the primary tumors were not detected. Hereby, we describe the rare case of a patient with metastatic PTC without initial visualization on imaging of primary tumor location along with inconsistent pathology results between fine needle aspiration (FNA) biopsy and gross specimen pathology results. A 60-year-old female with past medical history of Diabetes Mellitus type 2 and Hypothyroidism presenting for follow-up visit after being found with neck nodules on head and neck CT scan. Thyroid and neck Ultrasound (US) were performed finding three right irregularly shaped hypoechoic lymph nodes (LN's) measuring &amp;gt; 1 cm, concerning for metastatic disease, but no thyroid nodules were noted. Patient denies family history of thyroid cancer, and no head and neck radiation exposure. Physical examination did not reveal goiter or palpable nodules. Laboratory results: TSH: 2.95 and Total T4: 9.32, both within normal range. Cervical LN's FNA biopsy was performed, yielding results consistent with PTC tall cell variant. Chest CT scan showed suspicious lesions for pulmonary micrometastasis. Total thyroidectomy was performed and gross pathology findings showed an infiltrating, follicular variant PTC with multifocal tiny primary tumors of the thyroid, with lesions measuring up to 0.2 cm, dimension which explains why nodules could not be identified on imaging studies. LN's FNA biopsy results and thyroid pathology did not correlate. Thyroid gross pathology was clearly PTC with follicular variant, infiltrating a small area away from greatest dimension tumor, with cells with apparent dedifferentiation to tall cell cytologic features. Due to high risk of recurrence, radioactive iodine therapy was recommended as adjunctive therapy for metastatic disease and eradication of residual neck disease to be started with levels of TSH&amp;gt;30 mU/ml. Postopertative Thyroglobulin level (Tg) was adequate &amp;lt; 0. 01 ng/ml but unreliable based on above normal range antithyroglobulin antibody &amp;gt; 1000 IU/ml, which increases risk of recurrence. Whole body scan also done showing bilateral lung metastasis and small neck metastatic disease. Repeated postoperative thyroid US also demonstrated a suspicious cystic lymph node in right central neck for which FNA with saline washout of aspirate for Tg measurement was ordered. Metastatic thyroid carcinoma without primary tumor after extensive thyroid sampling is a rare but existent phenomenon that can be encountered in daily practice. Genotyping or immunostaining mestastatic lesions could help direct the Pathologist to the source of the metastasis. Patients with a higher risk of recurrence are monitored more aggressively as it is believed that early detection of recurrent disease offers the best opportunity for effective treatment. Presentation: No date and time listed

Demographic and pathologic factor regression to a growth rate model of p16-negative oral cavity squamous cell carcinoma.

ObjectivesThe current study aims to quantify the growth rate of p16‐negative oral cavity squamous cell carcinoma, characterize causative relationships between demographic risk factors and tumor growth, and examine pathologic findings associated with the tumor growth rate at a tertiary care institution. It is hypothesized that causative relationships will be drawn between the individual sociodemographic and pathologic factors and oral cavity p16‐negative squamous cell carcinoma growth rate.MethodsProspectively recruited participants, receiving surgical intervention only, were followed from initial staging CT scan to surgical resection. Interval growth was calculated in cm3/week. Demographic information including age, sex, smoking history, alcohol consumption history, previous all‐type malignancy, previous chemotherapy treatment, previous head or neck radiation exposure, and time interval elapsed between diagnosis and surgery was collected from each participant, and regression analysis was applied to determine causality.ResultsSummary statistics revealed a mean growth rate for the study sample of 1.385cm3/week. Statistically significant regression correlations were detected between tumor growth and alcohol consumption, origination at the retromolar trigone, and clinical nodal stage.ConclusionsThrough a small prospective cohort sample, the current study suggests clinical associations between alcohol consumption, origination at the retromolar trigone, and clinical nodal stage with rate of tumor growth. Future work will validate these relationships in a larger patient cohort, and against stronger modeling techniques.Level of EvidenceProspective non‐random cohort design.