Hasil untuk "Neoplasms. Tumors. Oncology. Including cancer and carcinogens"

N. Abu-Rustum, C. Yashar, R. Arend et al.

Adenocarcinoma of the endometrium (also known as endometrial cancer, or more broadly as uterine cancer or carcinoma of the uterine corpus) is the most common malignancy of the female genital tract in the United States. It is estimated that 65,950 new uterine cancer cases will have occurred in 2022, with 12,550 deaths resulting from the disease. Endometrial carcinoma includes pure endometrioid cancer and carcinomas with high-risk endometrial histology (including uterine serous carcinoma, clear cell carcinoma, carcinosarcoma [also known as malignant mixed Müllerian tumor], and undifferentiated/dedifferentiated carcinoma). Stromal or mesenchymal sarcomas are uncommon subtypes accounting for approximately 3% of all uterine cancers. This selection from the NCCN Guidelines for Uterine Neoplasms focuses on the diagnosis, staging, and management of pure endometrioid carcinoma. The complete version of the NCCN Guidelines for Uterine Neoplasms is available online at NCCN.org.

Fuzhuo Wang, Jiashuang Xu, Hong Sun et al.

BackgroundNumerous studies have demonstrated a close association between perceived stress and depression in colorectal cancer patients; however, the underlying mechanisms remain incompletely understood. This study aims to investigate the impact of perceived stress on depression in this population, as well as the mediating role of illness perception and the moderating role of self-efficacy.MethodA cross-sectional design was employed. From May to November 2024, a questionnaire survey was conducted among 290 colorectal cancer patients at two Grade A tertiary hospitals in Shenyang and Jinzhou, Liaoning Province, China. The questionnaire comprised sections on general demographics, perceived stress, illness perception, self-efficacy, and depression. Descriptive statistics and correlation analyses were performed using SPSS 25.0 and the PROCESS 3.5 macro. Mediation and moderation effects were tested using bootstrap resampling.ResultsA significant positive correlation was found between perceived stress and depression (β = 0.483, P < 0.001) and this relationship was partially mediated by illness perception (β = 0.083). Self-efficacy moderated the association between perceived stress and illness perception (β = 0.024, P < 0.001), with higher levels of self-efficacy strengthening the relationship between perceived stress and illness perception.ConclusionThis study identifies illness perception as a mediating pathway in the association between perceived stress and depression, while self-efficacy moderates the relationship between perceived stress and illness perception. Accordingly, a multidimensional clinical approach may be considered for addressing depressive symptoms in colorectal cancer patients. Such an approach could concurrently target perceived stress reduction, modification of illness perception, and enhancing self-efficacy.

Sangjin Ahn, Jang-Hyuk Yun

Cancer remains one of the leading causes of death worldwide, affecting not only humans but also companion animals such as dogs and cats. Although traditional rodent models have long served as the foundation of preclinical oncology research, their limited ability to replicate the complexity of spontaneous human cancers has driven interest in comparative oncology. Dogs and cats develop naturally occurring tumors that closely resemble human malignancies in histopathology, molecular alterations, tumor microenvironments, and treatment response. These species also share exposure to environmental carcinogens and demonstrate conserved pharmacokinetic and pharmacodynamic (PK/PD) profiles of several chemotherapeutic agents. This review provides a comprehensive comparison of cancer epidemiology, tumor biology, pharmacologic treatment modalities, drug formulation challenges, and regulatory considerations in humans, dogs, and cats. Key molecular targets such as TP53, HER2, EGFR, and PD-L1 exhibit cross-species conservation, supporting the relevance of companion animals in biomarker discovery and drug screening. However, interspecies differences in drug metabolism, enzyme expression (e.g., CYP450), and drug tolerability underscore the importance of species-specific dosing strategies and therapeutic drug monitoring. Advanced delivery platforms—including liposomes, nanoparticles, and antibody–drug conjugates—have also been successfully translated into veterinary oncology. Comparative analyses across humans and companion animals may inform biomarker prioritization, PK/PD modeling, and formulation design; however, species-specific differences require cautious interpretation and veterinary-centered dosing and safety considerations. Companion animals serve not only as valuable models for cancer research but also as direct beneficiaries of precision oncology. Future work should prioritize harmonized veterinary trial designs and improved cross-species data standards, with translational applications considered as a downstream benefit.

M. Tanguay, M. Tagliamento, J. Samaniego et al.

Clonal hematopoiesis (CH) refers to the expansion of hematopoietic stem and progenitor cells carrying somatic mutations and is increasingly identified in oncology through cell-free DNA testing. Once regarded mostly as a precursor to myeloid neoplasms and a contributor to cardiovascular disease, CH is now recognized as a major determinant of clinical outcomes in patients with cancer. Specific anticancer agents selectively promote the expansion of clones with DNA damage response gene mutations, particularly those with TP53 or PPM1D mutations, which are strongly associated with myeloid neoplasms post cytotoxic therapy (MN-pCT). The extent of clonal growth varies with treatment and, in some cases, may regress once therapy is withdrawn. In addition to therapy-driven clonal selection, inflammatory stress accelerates clonal expansion, creating a self-reinforcing cycle that contributes to atherosclerosis and other inflammation-associated complications. In oncology, CH-derived immune cells can infiltrate the tumor microenvironment and remodel local immunity, influencing tumor growth and treatment response. This tissue-infiltrating form of CH, termed tumor-infiltrating CH, has been associated with inferior survival in some cancer cohorts. Together, these findings establish CH as both a clinical challenge and an opportunity in modern oncology. Dedicated CH clinics and molecular tumor boards are emerging to address its implications for risk stratification, treatment selection, and survivorship care. This review examines the biology and clinical impact of CH in oncology, including its mutational spectrum, clonal evolution, role in MN-pCT, effects on inflammation and the tumor microenvironment, and emerging strategies for risk assessment and patient management.

Sara Lorenzoni, C. Rodríguez-Nogales, M. Blanco-Prieto

The need for precision therapies arises from the complexities associated with high-risk types of cancer, due to their aggressiveness and resistance to treatment. These diseases represent a global issue that requires transversal strategies involving cooperation among oncology specialists and experts from related fields, including nanomedicine. Nanoparticle-mediated active targeting of tumors has proven to be a revolutionary approach to address the most challenging neoplasms by overcoming the poor permeation at tumor site of untargeted, and nowadays questioned, strategies that rely solely on Enhanced Permeability and Retention (EPR) effects. The decoration of nanoparticles with Arg-Gly-Asp (RGD) peptides, which selectively target integrins on the cell membrane, marks a turning point in tumor microenvironment (TME) targeted strategies, enabling precision and efficiency in the delivery of chemotherapeutics. This review delves into the intricacies of the TME's features and targetable components (i.e. integrins), and the development of RGDs for nanoparticles' functionalization for active TME targeting. It provides a translational perspective on the integration of RGD-functionalized nanoparticles in oncology, highlighting their potential to overcome current therapeutic challenges, particularly in precision medicine. The current landscape of targeted nanomedicines in the clinic, and the development of RGD-nanomedicine for pediatric cancers are also discussed.

A. Doghish, Mohamed Bakr Zaki, Abdulrahman Hatawsh et al.

M. Rizzi, G. D’Annunzio, Chiara Tugnoli et al.

Companion animals develop spontaneous tumors with biological and immunological features closely resembling human cancers. The tumor microenvironment (TME), particularly its immune infiltrates, plays a pivotal role in tumor progression and immune evasion. This review summarizes current knowledge on the composition and function of immune cells (including T cells, B cells, macrophages, dendritic cells, neutrophils, and mast cells) in the TME of canine and feline tumors. A better understanding of these mechanisms may aid in identifying prognostic biomarkers and novel immunotherapeutic targets in both veterinary and human oncology.

Akanksha Sharma, L. Kennedy, Amanda E. D. Van Swearingen et al.

AbstractAbstract Intracranial metastases (ICM), specifically parenchymal brain metastases, remain a major clinical challenge in solid tumor oncology, despite recent advances in cancer therapies which have led to improvements in survival for these patients. Improving outcomes even further in this patient population will require a multi-disciplinary approach, including pre-clinical and translational studies, clinical trials, and studies of patient reported outcomes and quality of life. At the 2023 and 2024 joint Society for Neuro-Oncology (SNO) and American Society of Clinical Oncology (ASCO) CNS Metastases Conferences, two ICM collaborative group think tanks convened, composed of diverse, multi-disciplinary stakeholders, including basic and translational researchers, clinical trialists, and clinicians from academia and the community setting. Here we summarize the key knowledge gaps and consensus recommendations put forth by these two think tanks. Advances in ICM research and improvements in patient outcomes will require close inter-specialty and inter-institutional collaboration between stakeholders, including pre-clinical and translational researchers, clinical investigators, industry, and regulatory bodies.

Baskar Venkidasamy, Ashok Kumar Balaraman, Muthu Thiruvengadan

Jean S. Edward, Amanda Thaxton Wiggins, Louis G. Baser et al.

Few evidence-based trainings exist on how to equip healthcare providers, particularly nurses, with the skills to engage in cost of care conversations with patients/caregivers to mitigate the impact of cancer-related financial toxicity. This study evaluated a pilot training developed in collaboration with Triage Cancer^® to prepare oncology nurses to identify and assist patients/caregivers facing financial and/or legal barriers to care. Ten pediatric oncology nurses completed the training and pre/post-surveys on behaviors related to financial and legal need screening, frequency and comfort level of answering questions, knowledge, and behavior changes, along with training evaluation questions. At baseline, six nurses reported never screening for financial needs and nine for legal needs. Following the training, seven nurses stated they were likely to screen for financial/legal needs. At six months post-training, nurses had referred 85 patients/caregivers to financial/legal navigation services. Comfort levels in answering financial/legal questions increased by 6.5 points and knowledge scores increased by 1.7 points post-training. Most nurses recommended this training to other healthcare providers who work with patients with cancer and their caregivers. This study highlights the importance of providing oncology nurses with resources to engage in cost of care conversations and oncology financial legal navigation programs to mitigate the impact of cancer-related financial toxicity.

Lilla Bűdi, Dániel Hammer, Rita Varga et al.

ObjectivesSpingosine-1-phosphate (S1P) and ceramides are bioactive sphingolipids that influence cancer cell fate. Anti-ceramide antibodies might inhibit the effects of ceramide. The aim of this study was to assess the potential role of circulating S1P and anti-ceramide antibody as biomarkers in non-small cell lung cancer (NSCLC).MethodsWe recruited 66 subjects (34 controls and 32 patients with NSCLC). Patient history and clinical variables were taken from all participants. Venous blood samples were collected to evaluate plasma biomarkers. If bronchoscopy was performed, bronchial washing fluid (BWF) was also analyzed. We measured the levels of S1P and anti-ceramide antibody with ELISA.ResultsS1P levels were significantly higher in the NSCLC group (3770.99 ± 762.29 ng/mL vs. 366.53 ± 249.38 ng/mL, patients with NSCLC vs. controls, respectively, p < 0.001). Anti-ceramide antibody levels were significantly elevated in the NSCLC group (278.70 ± 19.26 ng/mL vs. 178.60 ± 18 ng/mL, patients with NSCLC vs. controls, respectively, p = 0.007). Age or BMI had no significant effect on anti-ceramide antibody or S1P levels. BWF samples had higher levels of anti-ceramide antibody (155.29 ± 27.58 ng/mL vs. 105.87 ± 9.99 ng/mL, patients with NSCLC vs. controls, respectively, p < 0.001). Overall survival (OS) was 13.36 months. OS was not affected by anti-ceramide antibody or S1P levels.ConclusionHigher levels of S1P and anti-ceramide antibody were associated with active cancer. These results suggest that sphingolipid alterations might be important features of NSCLC.

Sophia Daum, Lilith Decristoforo, Mira Mousa et al.

Abstract The dynamic interactions between tumor endothelial cells (TECs) and the immune microenvironment play a critical role in the progression of non-small cell lung cancer (NSCLC). In general, endothelial cells exhibit diverse immunomodulatory properties, influencing immune cell recruitment, antigen presentation, and regulation of immune checkpoint expression. Understanding the multifaceted roles of TECs as well as assigning specific functional hallmarks to various TEC phenotypes offer new avenues for targeted development of therapeutic interventions, particularly in the context of advanced immunotherapy and anti-angiogenic treatments. This review provides insights into the complex interplay between TECs and the immune system in NSCLC including discussion of potential optimized therapeutic opportunities.

Peichen Duan, Le Yu, Yichang Hao et al.

Abstract Purpose To investigate the prevalence of deficient DNA mismatch repair (dMMR) status in upper tract urothelial carcinoma (UTUC) and its association with clinicopathological characteristics as well as Nectin-4 immunohistochemical expression. Methods We retrospectively identified histologically confirmed UTUC cases treated at Peking University Third Hospital between December 2016 and September 2023. Eligible participants were required to also possess complete clinicopathological records and available formalin-fixed, paraffin-embedded (FFPE) tumor specimens suitable for immunohistochemical evaluation. MMR protein expression was categorized as either dMMR or proficient mismatch repair (pMMR), while Nectin-4 expression was quantitatively assessed using the H-score system. Samples were then classified as negative (H-score 0–14), low (H-score 15–99), medium (H-score 100–199), and high (H-score 200–300). Statistical significance was established at P < 0.05 using two-tailed tests. Results A total of 339 patients were deemed eligible, with specimens successfully evaluated. 25 patients (7.4%) demonstrated dMMR status. High Nectin-4 expression was observed in 124 patients (36.7%). A statistically significant association was identified between dMMR status and elevated Nectin-4 expression (P = 0.044). No significant differences were detected between dMMR and pMMR groups regarding clinical parameters, including gender, age, tumor grade, or immunophenotypic characteristics. Conclusion Our study revealed that 7.4% of UTUC patients exhibited dMMR status, with heterogeneous Nectin-4 expression observed across the cohort. Notably, we demonstrated a statistically significant correlation between dMMR status and elevated Nectin-4 expression, suggesting potential biological interplay. The combined biomarker profile warrants further investigation as a predictive tool for therapeutic strategies involving antibody–drug conjugates (e.g., enfortumab vedotin) and immune checkpoint inhibitors.

Fabiana Pozzuto Poppi, Felipe Noleto De Paiva, Marilia Gabriele Prado Albuquerque Ferreira et al.

Background: Cancer is a leading cause of death in dogs and cats, with its high prevalence linked to factors such as population growth, advances in veterinary medicine, and increased life expectancy. In Brazil, which had the 2nd largest pet population globally in 2017, the feline population is expanding rapidly and is expected to surpass dogs within a decade due to urbanization and lifestyle changes. Cancer epidemiology allows for the analysis of disease distribution, risk factors, and the impact of prevention and treatment on survival and quality of life. This study aims to conduct an epidemiological survey of feline oncology cases at the FCAV/UNESP Veterinary Hospital from 1997 to 2018. Materials, Methods & Results: This retrospective study analyzed 21 years of feline malignant neoplasms at a veterinary hospital. Data from medical records included patient characteristics, clinical history, diagnostics, treatments, and outcomes. Ethics approval was unnecessary, and owner consent was obtained. Medical records identified 70 cases of feline malignant neoplasms with adequate information. Epithelial tumors were the most prevalent (71.43%), with squamous cell carcinoma being the most common (72%), followed by mesenchymal neoplasms (18.57%) and round cell tumors (8.57%). Most affected patients were female (66%), predominantly aged between 7 and 14 years. Light-skinned bicolor cats were the most affected (34%), and 28% had outdoor access. Single lesions were the most frequent (42%), and 12% of tumors were smaller than 1 cm. Ulcerated tumors were observed in 30% of cases. The most affected regions included the mammary chain (26%), periocular areas (20%), and nasal planum (20%). Among treatment approaches, 78% of cats received therapy, with surgery, chemotherapy, cryosurgery, and electrochemotherapy being the most commonly used modalities. Mesenchymal tumors exclusively affected females, primarily in the subcutaneous tissue of the lateral abdomen (46.15%). Surgery was the primary treatment, followed by chemotherapy. Round cell neoplasms included lymphomas and mast cell tumors, mostly affecting the gastrointestinal tract and skin. Surgery and chemotherapy were the main treatment options, with 1 case surviving beyond 24 months. Squamous cell carcinoma was associated with sun exposure and light skin, characterized by ulcerated and invasive lesions. Injection-site sarcomas were predominantly found in vaccinated cats, confirming their association with injectable substances. Discussion: Squamous cell carcinoma (SCC) was the most common epithelial tumor, affecting outdoor cats with light skin and sparse fur, mainly in sun-exposed areas. Lesions were often ulcerated, adherent to muscle, and invasive to bone. Surgery, chemotherapy, cryosurgery, and electrochemotherapy were the main treatments, as radiotherapy and photodynamic therapy were unavailable locally. Feline injection-site sarcomas (FISS) predominantly affected vaccinated and neutered cats aged 7-10 years, consistent with literature. Tumors were mostly in subcutaneous tissue, showing infiltrative behavior. Surgical excision was the primary treatment, with histological subtypes including sarcomas and fibrous histiocytomas. Chemotherapy involved doxorubicin alone or combined with other agents. Lymphomas were the most frequent round cell tumors, with gastrointestinal and cutaneous forms observed. A senior cat with cutaneous lymphoma exhibited metastases, resembling cases in literature. Treatment included lomustine and prednisolone. The growing cat population in Brazil as well as around the world, brings a crescent need for further medical knowledge about the incidence of neoplastic processes in felines. Keywords: cancer, tumors, oncology, neoplasms, neoplastic process, feline.

V. M. Merabishvili, Z. Radzhabova, E. V. Levchenko et al.

In accordance with the International Classification of Diseases 10th Revision (ICD-10), malignant tumors (MT) of the nasal cavity and paranasal sinuses include diagnosis codes with sub-codes C30 and C31. In world and state statistics, summary data on morbidity is summarized under two diagnosis codes, C30 and C31. Our PCR database of the North-West Federal District of the Russian Federation contains more than 1.5 million cases, which allows us to consider the peculiarities of the prevalence of cancer in rare groups of malignant neoplasms. The population of the Northwestern Federal District of the Russian Federation is 13.9 million people, which is more than the population of Belarus, Latvia and Estonia combined.Objective. To study the prevalence and survival patterns of patients with malignant neoplasms of the nasal cavity, middle ear and paranasal sinuses using the database of the newly created NMR of the Northwestern Federal District of the Russian Federation, taking into account the detailed localization structure by subheadings: C30.0.1 and C31 with subheadings C31.0.1–3.8.9.Materials and methods. The study material is the data of the International Agency for Research on Cancer (IARC), reference books of the P.A. Herzen Moscow Oncology Research Institute and the N.N. Petrov National Medical Research Center of Oncology. Data processing was carried out using licensed programs MS Excel 2013–2016 and STATISTICA 6.1. A modified EUROCARE program was used to calculate survival. The calculations are based on the NMR of St. Petersburg and the Northwestern Federal District of the Russian Federation.Results and discussion. The conducted study with the analysis of prevalence, assessment of the quality of registration and survival of cancer patients with malignant neoplasms of the nasal cavity, middle ear and paranasal sinuses, confirmed the rarity of this pathology in the world and Russia. In general, a decrease in standardized morbidity rates, including age-related ones, was established. Improvement in the quality of registration of primary patients and provision of medical care was noted. An increase in the one-year survival of patients with malignant neoplasms of the nasal cavity, middle ear over three observation periods by 20.5% and paranasal sinuses by 15.4% was revealed. Five-year survival has remained virtually unchanged.

M. A. Polidanov, V. V. Maslyakov, Kirill A. Volkov et al.

Benign and malignant gastric neoplasms remain a significant problem in modern oncology and gastroenterology. According to the World Health Organization, gastric cancer is among the top five most common malignant tumors worldwide. Early diagnosis of these diseases is difficult due to the non-specificity of clinical symptoms in the initial stages, which often leads to late detection of malignant processes. The main diagnostic methods are endoscopic examination with biopsy, double-contrast radiography, endoscopic ultrasound, laboratory tests (including the determination of tumor marker levels), and morphological examination of biopsy specimens. Differential diagnosis between benign and malignant formations is crucial for choosing treatment tactics. The use of modern examination algorithms can improve the effectiveness of early detection of oncological diseases and enhance the prognosis for patients.

N. Vojjala, Deevyashali Parekh, A. Harisingani et al.

12043 Background: Radioimmunotherapy (RIT) utilizing monoclonal antibodies conjugated with therapeutic radionuclides, has emerged as a promising treatment option in oncology. While demonstrating significant clinical efficacy, concerns regarding therapy-related myeloid neoplasms (t-MNs) have been raised in other contexts, particularly following RIT for non-Hodgkin lymphoma. This study aims to investigate the risk of t-MNs following treatment with Lutathera (177Lu-DOTATATE) and Pluvicto (177Lu-PSMA-617) in patients with neuroendocrine tumors and metastatic castration-resistant prostate cancer. Methods: We conducted a multicenter retrospective study using the TrinetX database network, a federated Electronic Medical Record Network including adult patients with a history of using Lutathera and/or Pluvicto and developed t-MNs. Statistical analysis is performed on the TrinetX research platform. Outcome analysis was performed for 1) Incidence of t-MNs. 2) Mortality rates and Survival analysis. Results: A total of 2370 patients who received either Lutathera (n=1368; 57.7%) or Pluvicto (n=1002; 42.3%) were identified in the database. Mean age was 71 years (±11 years), 64.98% (n=1540) were males and 70.08% were whites. Of the 2370 patients, 1.6% (n=39) developed t-MNs (26 MDS (1.09%), 13 AML (0.54%). Among these, 27 were in the Lutathera cohort (1.97% of total patients), and 12 were in the Pluvicto cohort (1.12%). The mean age in the t-MN cohort was 72 years (±9 years) and 50% were males. 16 (41%) patients with t-MN had prior chemo or radiotherapy. The remaining 23 patients (59%) received no anticancer therapy associated with t-MNs. Median survival for patients with t-MNs was 38.1 months, with an overall mortality of 51.2% at median follow-up. Conclusions: This is the largest study reporting the incidence of t-MN associated with RIT. Our study demonstrated a significant risk of therapy-related t-MNs following RIT, even in patients who did not receive additional chemoradiotherapy. Given the short follow-up, we hypothesize that the risk may increase with longer-term follow-up. Using this real-world data, our Next step would be to include Next-Generation Sequencing for further characterization of the genomic landscape of these patients. Demographic, treatment, and follow-up data of the study population. Baseline characteristics RIT RIT with t-MNs Total patients 2370 39 Mean age (in years) (SD) 71 (±11) 72 (±9) Gender*(%)MalesFemales 64.9822.07 50.046.6 Race*(%)WhitesAfrican American 70.087.60 73.338.6 Radiation therapy (%)Chemotherapy (%)CabazitaxelDocetaxelCarboplatinCisplatinDoxorubicinOlaparib 20.2-5.2016.70.730.220.765.0 41.0 Median follow-up (in months) 11.4 27.3 Median survival (in months) (IQR) 44.5 (41.6-48.3) 38.1 (15-51.6) Mortality rates (%) 28.9 51.2 *Indicates remaining Unknown/Other; IQR: Interquartile range.

Reem Mohammed Jawad, Adil S. Aqabi, Zeineb Adnan

Ovarian cancer is the leading cause of gynecological cancer death and is the fifth most common cause of cancer-related death. Ovarian neoplasms are comprised of several distinct histopathology entities, with epithelial ovarian cancer accounting for 90% of all cases of malignant tumors of ovarian origin. Despite the mounting health concerns associated with obesity and its reported correlation with elevated mortality from certain forms of cancer, the association between obesity and ovarian cancer remains less delineated. The objective of this study is to ascertain the impact of excess body weight on survival outcomes and clinicopathological features of EOC in Iraqi patients. A retrospective study of 112 EOC patients was conducted at the Oncology Teaching Hospital in Baghdad. The data collected encompassed a wide range of variables, including age, BMI, histopathology, tumor grade, FIGO stage, surgical debulking method, and survival time. Kaplan-Meier and log-rank tests were used for survival analysis. Of the 112 patients included in the study, 50% were classified as overweight, 25% as obese, and 25% as having a normal BMI. Patients with obesity exhibited more advanced stages of the condition. The investigation revealed no substantial correlation between BMI and tumor grade, histopathology, or surgical outcomes. The median survival period was found to be 57 months in the normal weight group, 52 months in the overweight group, and 26 months in the obese group. P=0.15. Despite the absence of a statistically significant correlation between BMI and survival outcomes (p = 0.15), a clinically notable trend was observed, with obese patients demonstrating a reduced median survival duration. These findings suggest that while BMI alone may not be an independent prognostic factor, its potential clinical impact warrants further investigation in larger, adequately powered studies.

Haixia Jiang, Lan Li, Yunxia Bao et al.

Michael R. Sargen, Raymond L Barnhill, David E. Elder et al.

PURPOSE The purpose of this study was to develop recommendations for the diagnostic evaluation and surgical management of cutaneous melanoma (CM) and atypical Spitz tumors (AST) and non-Spitz melanocytic tumors (melanocytomas) in pediatric (age 0-10 years) and adolescent (age 11-18 years) patients. METHODS A Children's Oncology Group–led panel with external, multidisciplinary CM specialists convened to develop recommendations on the basis of available data and expertise. RESULTS Thirty-three experts from multiple specialties (cutaneous/medical/surgical oncology, dermatology, and dermatopathology) established recommendations with supporting data from 87 peer-reviewed publications. RECOMMENDATIONS (1) Excisional biopsies with 1-3 mm margins should be performed when feasible for clinically suspicious melanocytic neoplasms. (2) Definitive surgical treatment for CM, including wide local excision and sentinel lymph node biopsy (SLNB), should follow National Comprehensive Cancer Network Guidelines in the absence of data from pediatric-specific surgery trials and/or cohort studies. (3) Accurate classification of ASTs as benign or malignant is more likely with immunohistochemistry and next-generation sequencing. (4) It may not be possible to classify some ASTs as likely/definitively benign or malignant after clinicopathologic and/or molecular correlation, and these Spitz tumors of uncertain malignant potential should be excised with 5 mm margins. (5) ASTs favored to be benign should be excised with 1- to 3-mm margins if transected on biopsy. (6) Re-excision is not necessary if the AST does not extend to the biopsy margin(s) when complete/excisional biopsy was performed. (7) SLNB should not be performed for Spitz tumors unless a diagnosis of CM is favored on clinicopathologic evaluation. (8) Non-Spitz melanocytomas have a presumed increased risk for progression to CM and should be excised with 1- to 3-mm margins if transected on biopsy. (9) Re-excision of non-Spitz melanocytomas is not necessary if the lesion is completely excised on biopsy.