Neuroblastoma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

Neuroblastoma is the most common extracranial solid tumor diagnosed in children. This inaugural version of the NCCN Guidelines for Neuroblastoma provides recommendations for the diagnosis, risk classification, and treatment of neuroblastoma. The information in these guidelines was developed by the NCCN Neuroblastoma Panel, a multidisciplinary group of representatives with expertise in neuroblastoma, consisting of pediatric oncologists, radiologists, pathologists, surgeons, and radiation oncologists from NCCN Member Institutions. The evidence-based and consensus recommendations contained in the NCCN Guidelines are intended to guide clinicians in selecting the most appropriate treatments for their patients with this clinically heterogeneous disease.

Surgical management of rare tumors (Part 1).

With an annual cumulative occurrence of approximately 15,000 in North America, all childhood cancers are rare. Very rare cancers as defined by both the European Cooperative Study Group for Rare Pediatric Cancers and the Children's Oncology Group fall into two principal categories: those so uncommon (fewer than 2 cases/million) that their study is challenging even through cooperative group efforts (e.g., pleuropulmonary blastoma and desmoplastic small round cell tumor) and those that are far more common in adults and therefore rarely studied in children (e.g., thyroid, melanoma, and gastrointestinal stromal tumor). Treatment strategies for these latter tumors are typically based on adult guidelines, although the pediatric variants of these tumors may harbor different genetic signatures and demonstrate different behavior. If melanoma and differentiated thyroid cancer are excluded, other rare cancer types account for only 2% of the cancers in children aged 0 to 14. This article highlights several of the most common rare tumor types.

Let it glow: Intraoperative visualization of pulmonary metastases using pafolacianine, a next-generation fluorescent agent, for young adults undergoing pulmonary metastasectomy.

A new generation of disease-specific molecular imaging agents is poised to revolutionize fluorescence-guided surgery. Pafolacianine has been approved for adult lung and ovarian cancers. We demonstrate a proof of concept for pediatric surgeons treating young adults with pulmonary metastatic sarcomas. Five successful fluorescence-guided pulmonary metastasectomy operations were performed in young adult patients with metastatic osteosarcoma or Ewing sarcoma following administration of pafolacianine. All osteosarcoma lesions identified using standard techniques were also markedly fluorescent in patients. Novel fluorescent molecular agents targeted to tumor-specific receptors have promise of increased sensitivity and specificity for detecting metastatic nodules and enhancing surgical clearance of disease.

Synoptic operative reports for pediatric surgical oncology.

Synoptic operative notes for pediatric surgical oncology provide standardized and structured documentation of surgical procedures performed on pediatric patients with cancer. These reports capture essential details such as preoperative diagnosis, intraoperative findings, surgical technique, and tumor characteristics in a concise and uniform format. By promoting consistency, accuracy, and completeness in reporting, synoptic operative notes facilitate effective communication among multidisciplinary healthcare teams, enhance quality assurance efforts, and streamline data extraction for research purposes. The integration of synoptic reporting within electronic medical record systems further enhances accessibility and usability, ensuring efficient documentation practices and improved patient care outcomes in pediatric surgical oncology.

Contemporary surgical management of pediatric non-rhabdomyosarcoma soft tissue sarcoma.

Non-rhabdomyosarcoma soft tissue sarcoma (STS) comprises most STS in pediatric patients. It is a diverse set of over 30 histologic subtypes. Treatment is based on risk group determined by tumor size, grade, and the presence of metastases. Surgical resection is a cornerstone of therapy, as tumors are often resistant to chemotherapy or radiation. While patients with isolated tumors less than 5 cm may undergo upfront resection, strong consideration should be given to neoadjuvant chemoradiotherapy to ensure negative margins at surgical resection and optimal outcomes. Sentinel lymph node biopsy is strongly recommended for clear cell and epithelioid sarcomas. The most common metastatic site is the lung, and metastases should be resected at the end of therapy, when feasible. Unfortunately, many high-risk patients progress on therapy, and alternative strategies including earlier metastatic control require investigation.

Screening and Prophylaxis for Venous Thromboembolism in Pediatric Surgery: A Systematic Review.

OBJECTIVE: The American Pediatric Surgical Association Outcomes and Evidence-Based Practice Committee conducted a systematic review to describe the epidemiology of venous thromboembolism (VTE) in pediatric surgical and trauma patients and develop recommendations for screening and prophylaxis. METHODS: The Medline (Ovid), Embase, Cochrane, and Web of Science databases were queried from January 2000 through December 2021. Search terms addressed the following topics: incidence, ultrasound screening, and mechanical and pharmacologic prophylaxis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed. Consensus recommendations were derived based on the best available literature. RESULTS: One hundred twenty-four studies were included. The incidence of VTE in pediatric surgical populations is 0.29% (Range = 0.1%-0.48%) and directly correlates with surgery type, transfusion, prolonged anesthesia, malignancy, congenital heart disease, inflammatory bowel disease, infection, and female sex. The incidence of VTE in pediatric trauma populations is 0.25% (Range = 0.1%-0.8%) and directly correlates with injury severity, major surgery, central line placement, body mass index, spinal cord injury, and length-of-stay. Routine ultrasound screening for VTE is not recommended. Consider sequential compression devices in at-risk nonmobile, pediatric surgical patients when an appropriate sized device is available. Consider mechanical prophylaxis alone or with pharmacologic prophylaxis in adolescents >15 y and post-pubertal children <15 y with injury severity scores >25. When utilizing pharmacologic prophylaxis, low molecular weight heparin is superior to unfractionated heparin. CONCLUSIONS: While VTE remains an infrequent complication in children, consideration of mechanical and pharmacologic prophylaxis is appropriate in certain populations. TYPE OF STUDY: Systematic Review of level 2-4 studies. LEVEL OF EVIDENCE: Level 3-4.

Classification and Surgical Management of Anorectal Malformations: A Systematic Review and Evidence-based Guideline From the APSA Outcomes and Evidence-based Practice Committee.

OBJECTIVE: Treatment of neonates with anorectal malformations (ARMs) can be challenging due to variability in anatomic definitions, multiple approaches to surgical management, and heterogeneity of reported outcomes. The purpose of this systematic review is to summarize existing evidence, identify treatment controversies, and provide guidelines for perioperative care. METHODS: The American Pediatric Surgical Association Outcomes and Evidence Based Practice Committee (OEBP) drafted five consensus-based questions regarding management of children with ARMs. These questions were related to categorization of ARMs and optimal methods and timing of surgical management. A comprehensive search strategy was performed, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to perform the systematic review to attempt to answer five questions related to surgical care of ARM. RESULTS: A total of 10,843 publications were reviewed, of which 90 were included in final recommendations, and some publications addressed more than one question (question: 1 n = 6, 2 n = 63, n = 15, 4 n = 44). Studies contained largely heterogenous groups of ARMs, making direct comparison for each subtype challenging and therefore, no specific recommendation for optimal surgical approach based on outcomes can be made. Both loop and divided colostomy may be acceptable methods of fecal diversion for patients with a diagnosis of anorectal malformation, however, loop colostomies have higher rates of prolapse in the literature reviewed. In terms of timing of repair, there did not appear to be significant differences in outcomes between early and late repair groups. Clear and uniform definitions are needed in order to ensure similar populations of patients are compared moving forward. Recommendations are provided based primarily on A-D levels of evidence. CONCLUSIONS: Evidence-based best practices for ARMs are lacking for many aspects of care. Multi-institutional registries have made progress to address some of these gaps. Further prospective and comparative studies are needed to improve care and provide consensus guidelines for this complex patient population.

Embryonal sarcoma of the liver in pediatric and young adult patients: A report from Children's Oncology Group study ARST0332.

BACKGROUND: Embryonal sarcoma of the liver (ESL) is a rare mesenchymal tumor most common in childhood; the optimal treatment approach is uncertain. The clinical features and outcomes of patients with ESL enrolled in a Children's Oncology Group (COG) clinical trial that evaluated a risk-based strategy for treating soft tissue sarcomas in patients aged <30 years were evaluated. METHODS: This subset analysis included patients with ESL enrolled in COG study ARST0332. Central review of records, pathology, and imaging confirmed the diagnosis, presenting features, and surgery extent and complications. All patients received dose-intensive ifosfamide/doxorubicin chemotherapy, with cycle timing dependent on surgery and radiotherapy. Tumor resection occurred before study entry or after four cycles of chemotherapy; radiotherapy for residual tumor was optional. RESULTS: Thirty-nine eligible/evaluable patients with ESL were analyzed. All tumors were >10 cm in diameter; four were metastatic. Tumor resection was performed upfront in 23 and delayed in 16. Positive surgical margins (n = 6) and intraoperative tumor rupture (n = 6) occurred only in upfront resections. Eight patients received radiotherapy. Estimated 5-year event-free and overall survival were 79% (95% confidence interval [CI], 65%-93%) and 95% (95% CI, 87%-100%), respectively. Positive margins increased the local recurrence risk. One of 13 patients with documented hemorrhagic ascites and/or tumor rupture developed extrahepatic intra-abdominal tumor recurrence. CONCLUSIONS: The treatment strategy used in ARST0332 achieved favorable outcomes for patients with ESL despite a substantial proportion having high-risk disease features. Deferring tumor resection until after neoadjuvant chemotherapy may decrease the risk of intraoperative tumor rupture and improve the likelihood of adequate surgical margins.

Survival outcomes in pediatric patients with metastatic Ewing sarcoma who achieve a rapid complete response of pulmonary metastases.

PURPOSE: Our objectives were to compare overall survival (OS) and pulmonary relapse between patients with metastatic Ewing sarcoma (EWS) at diagnosis who achieve rapid complete response (RCR) and those with residual pulmonary nodules after induction chemotherapy (non-RCR). PATIENTS AND METHODS: This retrospective cohort study included children under 20 years with metastatic EWS treated from 2007 to 2020 at 19 institutions in the Pediatric Surgical Oncology Research Collaborative. Chi-square tests were conducted for differences among groups. Kaplan-Meier curves were generated for OS and pulmonary relapse. RESULTS: Among 148 patients with metastatic EWS at diagnosis, 61 (41.2%) achieved RCR. Five-year OS was 71.2% for patients who achieved RCR, and 50.2% for those without RCR (p = .04), and in multivariable regression among patients with isolated pulmonary metastases, RCR (hazards ratio [HR] 0.42; 95% confidence interval [CI]: 0.17-0.99) and whole lung irradiation (WLI) (HR 0.35; 95% CI: 0.16-0.77) were associated with improved survival. Pulmonary relapse occurred in 57 (37%) patients, including 18 (29%) in the RCR and 36 (41%) in the non-RCR groups (p = .14). Five-year pulmonary relapse rates did not significantly differ based on RCR (33.0%) versus non-RCR (47.0%, p = .13), or WLI (38.8%) versus no WLI (46.0%, p = .32). DISCUSSION: Patients with EWS who had isolated pulmonary metastases at diagnosis had improved OS if they achieved RCR and received WLI, despite having no significant differences in rates of pulmonary relapse.

Management of undifferentiated embryonal sarcoma of the liver: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Undifferentiated embryonal sarcoma of the liver (UESL) is a rare tumor for which there are few evidence-based guidelines. The aim of this study was to define current management strategies and outcomes for these patients using a multi-institutional dataset curated by the Pediatric Surgical Oncology Research Collaborative. METHODS: Data were collected retrospectively for patients with UESL treated across 17 children's hospitals in North America from 1989 to 2019. Factors analyzed included patient and tumor characteristics, PRETEXT group, operative details, and neoadjuvant/adjuvant regimens. Event-free and overall survival (EFS, OS) were the primary and secondary outcomes, respectively. RESULTS: Seventy-eight patients were identified with a median age of 9.9 years [interquartile range [IQR): 7-12]. Twenty-seven patients underwent resection at diagnosis, and 47 patients underwent delayed resection, including eight liver transplants. Neoadjuvant chemotherapy led to a median change in maximum tumor diameter of 1.6 cm [IQR: 0.0-4.4] and greater than 90% tumor necrosis in 79% of the patients undergoing delayed resection. R0 resections were accomplished in 63 patients (81%). Univariate analysis found that metastatic disease impacted OS, and completeness of resection impacted both EFS and OS, while multivariate analysis revealed that R0 resection was associated with decreased expected hazards of experiencing an event [hazard ratio (HR): 0.14, 95% confidence interval (CI): 0.04-0.6]. At a median follow-up of 4 years [IQR: 2-8], the EFS was 70.0% [95% CI: 60%-82%] and OS was 83% [95% CI: 75%-93%]. CONCLUSION: Complete resection is associated with improved survival for patients with UESL. Neoadjuvant chemotherapy causes minimal radiographic response, but significant tumor necrosis.

Factors Associated With Long-term Survival in Children With Bronchial and Lung Carcinoid Tumors.

BACKGROUND AND AIMS: Bronchial carcinoids are rare in children and the treatment is based on tumor behavior in adults. The purpose of this study was to determine factors and management strategies associated with long-term survival in the pediatric population using a national cohort. METHODS: Patients aged ≤20 years with bronchial carcinoid tumors were identified in the 2004-2020 National Cancer Database using ICD-O-3 codes. Tumor characteristics and management were compared among typical (TC) and atypical (AC) histological subtypes using Chi-square and Fisher's exact tests. Kaplan-Meier and univariate Cox proportional hazards analyses were used to assess survival. RESULTS: Of 273 patients, 251 (92%) had TCs, and 22(8%) had ACs. The median (IQR) age was 18 (16,19) years. Most patients underwent lobectomy or bilobectomy (67%), followed by sublobar resection (17%), no resection or bronchoscopic excision or ablation (8%), and pneumonectomy (7.7%). Margins were negative in 96%. Lymph node (LN) assessment was performed in 216 patients (84%) with a median (IQR) of 7(3,13) LNs, and 50 (23%) had ≥1 positive LN. There was no difference in age, resection, margin status, LN assessment, or positivity between TC and AC (all p > 00.05). Detection of nodal metastasis did not increase beyond the resection of 1-3 LNs (p = 0.72). Ten-year survival was worse for AC than TC (79% (41, 100) vs 98% (95, 100), HR = 6.9 (95% CI: 1.2-38.3, p = 0.03). Ten-year survival among those with and without LN assessment was 97% (94, 100) vs 91% (81, 100), HR = 4.0, 95% CI: 0.8-19.9, p = 0.09). There were no deaths in those with negative LN while 10-year survival was 89% (72, 100) in those with ≥1 positive LN. CONCLUSION: Among children with bronchial carcinoids, survival is excellent with TC or negative LN. Atypical histology and positive LN have poor survival and should prompt close monitoring. These risk factors may be missed in the absence of surgical resection and lymph node sampling. LEVEL OF EVIDENCE: III. TYPE OF STUDY: Retrospective Study.

Prevalence and outcomes of high versus low ratio plasma to red blood cell resuscitation in a multi-institutional cohort of severely injured children.

BACKGROUND: The benefit of targeting high ratio fresh frozen plasma (FFP)/red blood cell (RBC) transfusion in pediatric trauma resuscitation is unclear as existing studies are limited to patients who retrospectively met criteria for massive transfusion. The purpose of this study is to evaluate the use of high ratio FFP/RBC transfusion and the association with outcomes in children presenting in shock. METHODS: A post hoc analysis of a 24-institution prospective observational study (April 2018 to September 2019) of injured children younger than 18 years with elevated age-adjusted shock index was performed. Patients transfused within 24 hours were stratified into cohorts of low (<1:2) or high (≥1:2) ratio FFP/RBC. Nonparametric Kruskal-Wallis and χ 2 were used to compare characteristics and mortality. Competing risks analysis was used to compare extended (≥75th percentile) ventilator, intensive care, and hospital days while accounting for early deaths. RESULTS: Of 135 children with median (interquartile range) age 10 (5-14) years and weight 40 (20-64) kg, 85 (63%) received low ratio transfusion and 50 (37%) high ratio despite similar activation of institutional massive transfusion protocols (low-38%, high-46%, p = 0.34). Most patients sustained blunt injuries (70%). Median injury severity score was greater in high ratio patients (low-25, high-33, p = 0.01); however, hospital mortality was similar (low-24%, high-20%, p = 0.65) as was the risk of extended ventilator, intensive care unit, and hospital days (all p > 0.05). CONCLUSION: Despite increased injury severity, patients who received a high ratio of FFP/RBC had comparable rates of mortality. These data suggest high ratio FFP/RBC resuscitation is not associated with worst outcomes in children who present in shock. Massive transfusion protocol activation was not associated with receipt of high ratio transfusion, suggesting variability in MTP between centers. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Successful treatment of ulcerated hemangioma with diversion colostomy in a neonate with LUMBAR syndrome.

We present the case of a 3-week-old girl with LUMBAR syndrome, a rare condition involving segmental infantile hemangiomas (IH) in the lumbosacral region, myelopathy, and other congenital anomalies. The patient developed severe ulceration of a left buttock IH. Treatment included broad-spectrum antibiotics, debridement, and a laparoscopic temporary colostomy. Propranolol therapy, wound care, and fecal diversion led to successful healing of the ulceration. The report highlights the challenges of ulcerated IH in the perineal area due to exposure to urine and stool. The comprehensive approach resulted in positive outcomes, including the successful surgical treatment of spinal dysraphism, successful colostomy reversal, and developmental progress. This case contributes insight into the surgical management of severe perianal ulcerated IH associated with LUMBAR syndrome, highlighting the importance of a tailored surgical approach with a multidisciplinary framework.

Comparison of Outcomes Between Surveillance Ultrasound and Completion Lymph Node Dissection in Children and Adolescents With Sentinel Lymph Node-Positive Cutaneous Melanoma.

OBJECTIVE: To determine the impact of nodal basin ultrasound (US) surveillance versus completion lymph node dissection (CLND) in children and adolescents with sentinel lymph node (SLN) positive melanoma. BACKGROUND: Treatment for children and adolescents with melanoma are extrapolated from adult trials. However, there is increasing evidence that important clinical and biological differences exist between pediatric and adult melanoma. METHODS: Patients ≤18 years diagnosed with cutaneous melanoma between 2010 and 2020 from 14 pediatric hospitals were included. Data extracted included demographics, histopathology, nodal basin strategies, surveillance intervals, and survival information. RESULTS: Of 252 patients, 90.1% (n=227) underwent SLN biopsy (SLNB), 50.9% (n=115) had at least 1 positive node. A total of 67 patients underwent CLND with 97.0% (n=65/67) performed after a positive SLNB. In contrast, 46 total patients underwent US observation of nodal basins with 78.3% (n=36/46) of these occurring after positive SLNB. Younger patients were more likely to undergo US surveillance (median age 8.5 y) than CLND (median age 11.3 y; P =0.0103). Overall, 8.9% (n=21/235) experienced disease recurrence: 6 primary, 6 nodal, and 9 distant. There was no difference in recurrence (11.1% vs 18.8%; P =0.28) or death from disease (2.2% vs 9.7%; P =0.36) for those who underwent US versus CLND, respectively. CONCLUSIONS: Children and adolescents with cutaneous melanoma frequently have nodal metastases identified by SLN. Recurrence was more common among patients with thicker primary lesions and positive SLN. No significant differences in oncologic outcomes were observed with US surveillance and CLND following the identification of a positive SLN.

Management and Outcomes of Wilms Tumor With Suprarenal Intravascular Extension: A Pediatric Surgical Oncology Research Collaborative Study.

OBJECTIVE: The purpose of this study was to describe management and outcomes from a contemporary cohort of children with Wilms tumor complicated by inferior vena caval thrombus. BACKGROUND: The largest series of these patients was published almost 2 decades ago. Since then, neoadjuvant chemotherapy has been commonly used to manage these patients, and outcomes have not been reported. METHODS: Retrospective review of 19 North American centers between 2009 and 2019. Patient and disease characteristics, management, and outcomes were investigated and analyzed. RESULTS: Of 124 patients, 81% had favorable histology (FH), and 52% were stage IV. IVC thrombus level was infrahepatic in 53 (43%), intrahepatic in 32 (26%), suprahepatic in 14 (11%), and cardiac in 24 (19%). Neoadjuvant chemotherapy using a 3-drug regimen was administered in 82% and postresection radiation in 90%. Thrombus level regression was 45% overall, with suprahepatic level showing the best response (62%). Cardiopulmonary bypass (CPB) was potentially avoided in 67%. The perioperative complication rate was significantly lower after neoadjuvant chemotherapy [(25%) vs upfront surgery (55%); P =0.005]. CPB was not associated with higher complications [CPB (50%) vs no CPB (27%); P =0.08]. Two-year event-free survival was 93% and overall survival was 96%, higher in FH cases (FH 98% vs unfavorable histology/anaplastic 82%; P =0.73). Neither incomplete resection nor viable thrombus cells affected event-free survival or overall survival. CONCLUSIONS: Multimodal therapy resulted in excellent outcomes, even with advanced-stage disease and cardiac extension. Neoadjuvant chemotherapy decreased the need for CPB to facilitate resection. Complete thrombectomy may not always be necessary.

Critical elements of pediatric rhabdomyosarcoma surgery.

Rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in children, requires multimodal therapy which is determined by risk group stratification. Local control may be achieved by surgical resection, radiation, or both. Resection may occur upfront or following induction chemotherapy as a delayed primary excision. An R1 resection may allow a reduction in radiation exposure; however, debulking is not indicated nor is excision of residual masses at the end of therapy. Regional lymph node assessment is an important component of surgical care, as positive nodal basins require radiation. Depending on the tumor site and biology, sentinel lymph node biopsy vs biopsy of clinically or radiographically concerning nodes is indicated. Therapeutic lymph node dissection is never indicated. Familiarity with site-specific oncologic principles for RMS and participation in a multidisciplinary team including Pediatric Oncology and Radiation Oncology are necessary components of surgical care to ensure optimal outcomes.

Crystalloid volume is associated with short-term morbidity in children with severe traumatic brain injury: An Eastern Association for the Surgery of Trauma multicenter trial post hoc analysis.

OBJECTIVE: This study examined differences in clinical and resuscitation characteristics between injured children with and without severe traumatic brain injury (sTBI) and aimed to identify resuscitation characteristics associated with improved outcomes following sTBI. METHODS: This is a post hoc analysis of a prospective observational study of injured children younger than 18 years (2018-2019) transported from the scene, with elevated shock index pediatric-adjusted on arrival and head Abbreviated Injury Scale score of ≥3. Timing and volume of resuscitation products were assessed using χ 2t test, Fisher's exact t test, Kruskal-Wallis, and multivariable logistic regression analyses. RESULTS: There were 142 patients with sTBI and 547 with non-sTBI injuries. Severe traumatic brain injury patients had lower initial hemoglobin (11.3 vs. 12.4, p < 0.001), greater initial international normalized ratio (1.4 vs. 1.1, p < 0.001), greater Injury Severity Score (25 vs. 5, p < 0.001), greater rates of ventilator (59% vs. 11%, p < 0.001) and intensive care unit (ICU) requirement (79% vs. 27%, p < 0.001), and more inpatient complications (18% vs. 3.3%, p < 0.001). Severe traumatic brain injury patients received more prehospital crystalloid (25% vs. 15%, p = 0.008), ≥1 crystalloid boluses (52% vs. 24%, p < 0.001), and blood transfusion (44% vs. 12%, p < 0.001) than non-sTBI patients. Among sTBI patients, receipt of ≥1 crystalloid bolus (n = 75) was associated with greater ICU need (92% vs. 64%, p < 0.001), longer median ICU (6 vs. 4 days, p = 0.027) and hospital stay (9 vs. 4 days, p < 0.001), and more in-hospital complications (31% vs. 7.5%, p = 0.003) than those who received <1 bolus (n = 67). These findings persisted after adjustment for Injury Severity Score (odds ratio, 3.4-4.4; all p < 0.010). CONCLUSION: Pediatric trauma patients with sTBI received more crystalloid than those without sTBI despite having a greater international normalized ratio at presentation and more frequently requiring blood products. Excessive crystalloid may be associated with worsened outcomes, including in-hospital mortality, seen among pediatric sTBI patients who received ≥1 crystalloid bolus. Further attention to a crystalloid sparing, early transfusion approach to resuscitation of children with sTBI is needed. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Plasma thrombin generation kinetics vary by injury pattern and resuscitation characteristics in pediatric and young adult trauma patients.

BACKGROUND: Thrombin generation kinetics are not well studied in children. This study aimed to assess how thrombin generation kinetics vary in pediatric and young adult (YA) trauma patients by clinical characteristics and injury pattern. METHODS: Prospective cohort study where plasma samples were obtained from pediatric (ages 0-17 years) and YA (ages 18-21 years) trauma patients upon emergency department arrival. Thrombin generation (calibrated automated thrombogram [CAT]) was quantified as lag time (LT, minutes), peak height (PH, nM), time to peak (ttPeak, minutes), and endogenous thrombin potential (ETP, nM × minute). Results are expressed as median and quartiles [Q1, Q3] and compared using Wilcoxon rank sum testing with p < 0.05 considered significant. RESULTS: We enrolled 47 pediatric (median age, 15 [14, 17] years, 78% male, 87% blunt, median Injury Severity Score, 12) and 49 YA (median age 20 [18, 21] years, 67% male, 84% blunt, median Injury Severity Score, 12) patients. Pediatric and YA patients had similar rates of operative intervention (51% vs. 57%), transfusion (25% vs. 20%), and traumatic brain injury (TBI) (53% vs. 49%). Pediatric patients who required an operation had accelerated initiation of thrombin generation, with shorter LT than those who did not (2.58 [2.33, 2.67]; 2.92 [2.54, 3.00], p = 0.034). Shorter LT (2.41 [2.22, 2.67]; 2.67 [2.53, 3.00]) and ttPeak (4.50 [4.23, 4.73]; 5.22 [4.69, 5.75], both p < 0.01) were noted in pediatric patients who required transfusion as compared with those who did not. The YA patients requiring transfusion had shorter LT (2.33 [2.19, 2.74]; 2.83 [2.67, 3.27]) and ttPeak (4.48 [4.33, 5.65]; 5.33 [4.85, 6.28] both p < 0.04) than those who were not transfused. Young adults with TBI had greater ETP than those without (1509 [1356, 1671]; 1284 [1154, 1471], p = 0.032). CONCLUSION: Thrombin generation kinetics in pediatric trauma patients prior to intervention vary with need for operation and transfusion, while thrombin generation kinetics in young adult patients are influenced by TBI and need for operation or transfusion. This is a promising tool for assessing coagulopathy in young trauma patients. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.