JAK inhibitor treatment for inborn errors of JAK/STAT signaling: An ESID/EBMT-IEWP retrospective study.

BACKGROUND: Inborn errors of immunity (IEI) with dysregulated JAK/STAT signaling present with variable manifestations of immune dysregulation and infections. Hematopoietic stem cell transplantation (HSCT) is potentially curative, but initially reported outcomes were poor. JAK inhibitors (JAKi) offer a targeted treatment option that may be an alternative or bridge to HSCT. However, data on their current use, treatment efficacy and adverse events are limited. OBJECTIVE: We evaluated the current off-label JAKi treatment experience for JAK/STAT inborn errors of immunity (IEI) among European Society for Immunodeficiencies (ESID)/European Society for Blood and Marrow Transplantation (EBMT) Inborn Errors Working Party (IEWP) centers. METHODS: We conducted a multicenter retrospective study on patients with a genetic disorder of hyperactive JAK/STAT signaling who received JAKi treatment for at least 3 months. RESULTS: Sixty-nine patients (72% children) were evaluated (45 STAT1 gain of function [GOF], 21 STAT3-GOF, 1 STAT5B-GOF, 1 suppressor of cytokine signaling 1 [aka SOCS1] loss of function, 1 JAK1-GOF). Ruxolitinib was the predominantly prescribed JAKi (80%). Overall, treatment resulted in improvement (partial or complete remission) of clinical symptoms in 87% of STAT1-GOF and in 90% of STAT3-GOF patients. We documented highly heterogeneous dosing and monitoring regimens. The response rate and time to response varied across different diseases and manifestations. Adverse events including infection and weight gain were frequent (38% of patients) but were mild (grade I-II) and transient in most patients. At last follow-up, 52 (74%) of 69 patients were still receiving JAKi treatment, and 11 patients eventually underwent HSCT after receipt of previous JAKi bridging therapy, with 91% overall survival. CONCLUSIONS: Our study suggests that JAKi may be highly effective to treat symptomatic JAK/STAT IEI patients. Prospective studies to define optimal JAKi dosing for the variable clinical presentations and age ranges should be pursued.

NUT carcinoma in pediatric patients: Characteristics, therapeutic regimens, and outcomes of 11 cases registered with the German Registry for Rare Pediatric Tumors (STEP).

BACKGROUND AND AIMS: Nuclear protein of the testis (NUT) carcinoma (NC) is a rare and highly aggressive tumor defined by the presence of a somatic NUTM1 rearrangement, occurring mainly in adolescents and young adults. We analyzed the clinical and biological features of German pediatric patients (≤18 years) with NC. METHODS: This study describes the characteristics and outcome of 11 children with NC registered in the German Registry for Rare Pediatric Tumors (STEP). RESULTS: Eleven patients with a median age of 13.2 years (range 6.6-17.8) were analyzed. Malignant misdiagnoses were made in three patients. Thoracic/mediastinal tumors were found to be the primary in six patients, head/neck in four cases; one patient had multifocal tumor with an unknown primary. All patients presented with regional lymph node involvement, eight patients (72.7%) with distant metastases. Seven patients underwent surgery, eight radiotherapy with curative intent; polychemotherapy was administered in all patients. Novel treatment strategies including immunotherapy, targeted therapies, and virotherapy were applied in three patients. Median event-free survival and overall survival were 1.5 and 6.5 months, respectively. CONCLUSIONS: Every undifferentiated or poorly differentiated carcinoma should undergo testing for the specific rearrangement of NUTM1, in order to initiate an intense therapeutic regimen as early as possible. As in adults, only few pediatric patients with NC achieve prolonged survival. Thus, novel therapeutic strategies should be included and tested in clinical trials.

Incidences and characteristics of primary lung malignancies in childhood in Germany: An analysis of population-based data from German cancer registries.

BACKGROUND: Primary lung malignancies are a heterogeneous group of cancers that occur very rarely in childhood. Due to limited knowledge of their epidemiologic and clinical features, these tumors present a challenge to the treating physicians. This study aimed to increase the knowledge about the occurrence of primary lung malignancies in childhood in Germany. MATERIALS AND METHODS: Pseudonymized data of cases recorded at the German Center for Cancer Registry Data (ZfKD) between 1990 and 2017 were retrieved. Primary lung malignancies were identified using the ICD- and ICD-O classification. Numbers were compared to those reported to the German Childhood Cancer Registry (GCCR). Crude incidence rates were calculated using the ZfKD database. RESULTS: A total of 168 patients diagnosed with primary lung malignancies in the age below 19 years were identified from the ZfKD. The median age at diagnosis was 13 years. The most common tumor entities were lung carcinoids (n = 49), lung carcinoma (n = 36), and pleuropulmonary blastoma (n = 14). An unexpected accumulation of lung cancer cases was noted in the first year of life without a clearly specified histopathological diagnosis. A substantial discrepancy in the numbers of primary lung malignancies between ZfKD and GCCR was found. CONCLUSIONS: We present population-based data on the occurrence of primary childhood lung malignancies in Germany, which were more frequent than previously anticipated but likely remained underreported. For better understanding and optimal treatment of these entities, cancer registration needs to be improved through mandatory reporting to the GCCR and regular data sharing between GCCR, population-based and clinical cancer registries.

Pseudohypoxic pheochromocytomas and paragangliomas dominate in children.

OBJECTIVE: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors that are associated with cancer predisposition syndromes in up to 80% of affected children. PPGLs can be divided into molecularly defined groups with comparable pathogenesis and biology: (1) pseudohypoxic, (2) kinase signaling, and (3) Wnt-altered. METHODS: We report the data of children and adolescents diagnosed with PPGL who have been registered with the German GPOH-MET registry since 1997. RESULTS: By December 2019, a total of 88 patients with PPGL were reported. Pheochromocytoma occurred in 56%, paraganglioma in 35%, and synchronous PPGLs in 9.1%. A total of 16% of patients presented with lymph node (5.7%) and distant metastases (10%). Median follow-up was 4.2 years (range 0-17.1). Overall and disease-free survival (DFS) were 98.6% and 54.0%, respectively. Local relapses, metastases, and subsequent PPGLs occurred in 11%, 4.5%, and 15% of patients. Germline mutations were detected in 83% of patients (51% in VHL, 21% in SDHB, 7.8% in SDHD, and one patient each in RET and NF1). One patient was diagnosed with Pacak-Zhuang syndrome. A total of 96% of patients presented with PPGL of the pseudohypoxic subgroup (34% TCA cycle-related, 66% VHL/EPAS1-related). In multivariate analyses, extent of tumor resection was a significant prognostic factor for DFS. CONCLUSIONS: Most pediatric PPGLs belong to the pseudohypoxia subgroup, which is associated with a high risk of subsequent PPGL events and metastatic disease. Comprehensive molecular profiling of children and adolescents with newly diagnosed PPGLs will open new avenues for personalized diagnosis, treatment, and surveillance.

Adrenocortical tumours in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations.

Adrenocortical tumours (ACTs) are rare during childhood. A complete surgical resection provides the best chance of cure, but the role and efficacy of the adjuvant therapy are still controversial. Various histologic criteria of malignancy for ACTs adopted in children do not facilitate comparative studies and are not completely shared. Therefore, a sharp demarcation between benign and malignant lesions has not been recognised, making it difficult to identify who potentially needs perioperative therapy. This manuscript presents the internationally harmonised recommendations for the diagnosis and treatment of ACTs in children and adolescents, established by the European Cooperative Study Group for Paediatric Rare Tumours (EXPeRT) group within the EU-funded project PARTNER (Paediatric Rare Tumours Network - European Registry).

Multiple endocrine neoplasia type 2B: Frequency of physical stigmata-Results of the GPOH-MET registry.

BACKGROUND: Multiple endocrine neoplasia (MEN) 2B is characterized by early development of aggressive medullary thyroid carcinoma (MTC), visible physical stigmata, and associated symptoms. In most cases, de novo mutations are revealed. There are premonitory symptoms and stigmata that enable early diagnosis, before an inoperable MTC develops. The German Society for Paediatric Oncology and Haematology (GPOH)-Malignant Endocrine Tumours (MET) registry maintains records of children with MTC in Germany since 1997. METHODS: Children with a diagnosis of MTC in MEN 2B recorded in the GPOH-MET study were analyzed retrospectively. Stigmata and symptoms associated with MEN 2B were examined. RESULTS: From inception through 2017, 24 patients aged 0.2-17.3 years were included. Symptoms affecting the oral/dental (88.0%), musculoskeletal (79.2%), and gastrointestinal (70.8%) systems were recognized most frequently. Gastrointestinal and musculoskeletal symptoms preceded symptoms of MTC. Twelve patients had short stature. Regarding the prevalence of single symptoms, neuromas of the lips and the oral cavity were mentioned most frequently. Five patients died from MTC. Patients diagnosed by tumor symptoms showed more advanced disease than those with disease detected by other means. Children diagnosed via associated stigmata and symptoms or positive family history had significantly improved overall survival (OS) compared to children diagnosed via symptoms of MTC (OS 100% vs 53.3%). CONCLUSIONS: In children with MEN 2B, oral/dental, musculoskeletal, and gastrointestinal symptoms are most common. If children are diagnosed via associated symptoms and stigmata, OS is improved. Most of the children were diagnosed with growth disturbances; this finding requires verification and ranging in other patient cohorts.

Revisiting the genotype-phenotype correlation in children with medullary thyroid carcinoma: A report from the GPOH-MET registry.

BACKGROUND: Medullary thyroid carcinomas (MTC) account for 3% to 5% of all thyroid cancers. In most cases, MTC is hereditary and occurs as part of the multiple endocrine neoplasia (MEN) type 2A and 2B syndromes. There is a strong genotype-phenotype correlation associated with the respective RET mutations, making risk-adapted management possible. PROCEDURE: We report the prospectively collected data on children and adolescents of the multicenter nonrandomized German GPOH-MET registry. Children and adolescents with MTC and C-cell hyperplasia (CCH) were included. RESULTS: From 1997 to June 2019, a total of 57 patients with MTC and 17 with CCH were reported. In patients with MTC, median follow-up was five years (range, 0-19) and median age at diagnosis 10 years (range, 0-17). Overall survival and event-free survival (EFS) were 87% and 52%, respectively. In total 96.4% of patients were affected by MEN2 syndromes, which was in 37/42 MEN2A and 3/28 MEN2B (M918T mutation) inherited. EFS in MEN2A was 78%, and in MEN2B 38% (P < 0.001). In multivariate analyses, lymph node (LN) status and postoperatively elevated calcitonin were significant prognostic factors for EFS. Notably, modest-risk mutation carriers presented with MTC at a rather young age, without raised calcitonin, and LN metastases. CONCLUSIONS: Identification of children carrying de novo RET M918T mutations by means of the characteristic phenotype is crucial to detect MTC at an early stage, which will be associated with improved survival. As calcitonin levels may be false-negative and modest-risk mutation carriers present with a variable phenotype, particular attention should be paid to these children.

[Cervical lymphadenitis caused by non-tuberculous mycobacteria in children with different residence]. / Zervikale Lymphadenitis durch atypische Mykobakterien bei Kindern mit unterschiedlichem Wohnsitz.

OBJECTIVE: Atypical mycobacteria form a heterogeneous group. Although more than 140 species have been identified, only 25 of them are considered responsible for infection in humans. The most frequent manifestation of the disease in immunocompetent children is the cervical lymphadenitis. Aims of this study were to identify a correlation of the location of residence with patients' demographics and disease characteristics, to evaluate the ultrasonographic findings and the different operative treatments modalities and to develop an algorithm for the diagnosis and treatment. MATERIALS AND METHODS: Cases were identified by using the hospital's correspondence, microbiology and pathology databases. Demographic and clinical data were collected. A statistical analysis of the results was performed. RESULTS: 32 patients were included. Our data revealed no significant correlation between area of residence and disease characteristics. Hypoechoic lymph nodes with intraglandular necrosis and low vascularity were observed in the majority of patients. Surgical treatment included abscess incision with biopsy, lymphadenectomy, selective neck dissection and partial parotidectomy. A recurrent disease was significantly more frequent after abscess incision. CONCLUSIONS: Further studies with prospective design are required, in order to confidently identify the correlation between area of residence and disease characteristics. Similar ultrasonographic findings suggest a constant constellation of changes that facilitate diagnostic evaluation. Complete surgical excision offers an effective management option as it combines definitive treatment and histological confirmation with low risk of complications.

Incidence and Temporal Patterns of Differentiated Thyroid Carcinoma in Children and Adolescents in Germany: A Pooled Analysis Based on Data from the German Malignant Endocrine Tumor Registry and the German Childhood Cancer Registry.

Introduction: The increasing incidence of differentiated thyroid carcinoma (DTC) in children and adolescents has become a growing concern. This study provides the first extensive assessment of incidence patterns and temporal trends of pediatric DTC in Germany, using the best available data from the German Malignant Endocrine Tumor (MET) Registry and the German Childhood Cancer Registry (GCCR) covering a period of 25 years. Patients and Methods: We conducted a register-based incidence and time series analysis, identifying all children and adolescents diagnosed with DTC at ages 0-17 years between 1997 and 2021 in Germany, as recorded in the German MET Registry and/or the GCCR. Age-specific and age-standardized incidence rates (ASR) over time, average annual percentage changes (AAPC), and cross-tabulations were used to evaluate incidence and temporal patterns. Results: We identified 469 DTC cases, including 85.7% papillary thyroid cancer and 9.4% follicular thyroid cancer. The average ASR for the period 1997-2021 was 1.16 per million, with higher rates in females compared with males (1.64 vs. 0.72 per million, respectively). Incidence rates increased with increasing age. The overall ASR increased from 0.84 per million in 1997-2001 to 1.48 per million in 2017-2021, with an AAPC of 3.46% [confidence interval or CI: 2.12-4.83]. The increase was most pronounced in adolescents aged 15-17 years (AAPC: 6.79% [CI: 4.43-9.19]). The proportion of incidentalomas rose from 5% in 1997-2001 to 26% in 2017-2021, yet we observed no marked shift in tumor size between symptomatic and incidental cases. Conclusions: Our study revealed a significant increase in pediatric DTC incidence in Germany, most pronounced among adolescents. The observation of an increasing incidence mirrors global trends and presents a complex public health challenge. While improved detection likely contributes to this trend, the stable tumor size distribution suggests that other factors are also in play. The rising detection of incidentalomas suggests enhanced diagnostic practices unrelated to symptoms of thyroid neoplasia. These findings highlight the need to carefully evaluate diagnostic and screening practices in pediatric populations.

The Endocrine Phenotype Induced by Pediatric Adrenocortical Tumors Is Age- and Sex-Dependent.

CONTEXT: Adrenocortical carcinomas are very rare malignancies in childhood associated with poor outcome in advanced disease. Most adrenocortical tumors (ACT) are functional, causing signs and symptoms of adrenal hormone excess. In most studies, endocrine manifestations were reported 4 to 6 months prior to diagnosis. OBJECTIVE: We sought to extend knowledge on endocrine manifestations with regard to age and sex to facilitate early diagnosis. METHODS: We retrospectively analyzed features of adrenal hormone excess in children and adolescents with ACT registered with the GPOH-MET studies between 1997 and 2022. Stage of puberty was defined as prepubertal in females < 8 years of age and males < 9 years. RESULTS: By December 2022, 155 patients (110 female, 45 male) with data on endocrine manifestations had been reported. Median age at ACT diagnosis was 4.2 years [0.1-17.8], median interval from first symptoms was 4.2 months [0-90.7]. In 63 girls of prepubertal age, the most frequently reported manifestations were pubarche (68.3%), clitoral hypertrophy (49.2%), and weight gain (31.7%); in 47 pubertal female patients, the most frequent manifestations were excessive pubic hair (46.8%), acne (36.2%), and hypertension (36.2%). Leading symptoms in 34 boys of prepubertal age were pubarche (55.9%), penile growth (47.1%), and acne (32.4%), while in 11 pubertal male patients, leading symptoms were weight gain (45.5%), hypertension (36.4%), excessive pubic hair (27.3%), and cushingoid appearance (27.3%). In pubertal patients, symptoms of androgen excess were mainly unrecognized as part of pubertal development, while symptoms of Cushing syndrome were more frequently apparent. CONCLUSION: The endocrine phenotype induced by pediatric ACT is age- and sex-dependent.

Lymph node metastases are more frequent in paediatric appendiceal NET ≥1.5 cm but without impact on outcome - Data from the German MET studies.

BACKGROUND: Paediatric appendiceal neuroendocrine tumours (appNET) are very rare tumours, mostly detected incidentally by histopathological evaluation after appendectomy. Treatment recommendations are based on adult data considering high-risk NET as defined by European Neuroendocrine Tumour Society (ENETS) guidelines for completion right-sided hemicolectomy (RHC). Recent data suggest that less aggressive therapy may be justified. PROCEDURE: Analysis of children and adolescents with appNET prospectively registered with the German Malignant Endocrine Tumour (MET) studies between 1997 and 2022. RESULTS: By December 2022, 662 patients (64.7% females, 35.3% male) had been reported. Median age was 13.3 years [4.5-17.9], median duration of follow-up 2.2 years [0-10.9]. No distant metastases were reported. Tumour size was <1 cm in 63.5%, 1-2 cm in 33.2%, and >2 cm in 3.2% of patients. WHO grade 1 and 2 tumours were diagnosed in 76.9% and 23.1% of patients, respectively. Lymphovascular invasion and lymph node metastases were associated with tumour size ≥1.5 cm. 27.0% of patients presented with high-risk NET according to ENETS criteria. Of those, only 55.9% underwent secondary oncological right hemicolectomy. Neither distant metastases, nor recurrences or disease-related deaths occurred in patients with appendectomy only as well as in patients with completion RHC. Overall and event-free survival were both 100%. CONCLUSIONS: Internationally harmonized consensus recommendations on treatment of children and adolescents with appendiceal NET are urgently needed to avoid completion RHC in high-risk patients.

Assessment of prognostic factors in pediatric adrenocortical tumors: the modified pediatric S-GRAS score in an international multicenter cohort-a work from the ENSAT-PACT working group.

OBJECTIVE: Pediatric adrenocortical carcinoma (pACC) is rare, and prognostic stratification remains challenging. We aimed to confirm the prognostic value of the previously published pediatric scoring system (pS-GRAS) in an international multicenter cohort. DESIGN: Analysis of pS-GRAS items of pACC from 6 countries in collaboration of ENSAT-PACT, GPOH-MET, and IC-PACT. METHODS: We received patient data of the pS-GRAS items including survival information from 9 centers. PS-GRAS score was calculated as a sum of tumor stage (1 = 0; 2-3 = 1; 4 = 2 points), grade (Ki67 index: 0%-9% = 0; 10%-19% = 1; ≥20% = 2 points), resection status (R0 = 0; RX/R1/R2 = 1 point), age (<4 years = 0; ≥4 years = 1 point), and hormone production (androgen production = 0; glucocorticoid-/mixed-/no-hormone production = 1 point) generating 8 scores and 4 groups (1: 0-2, 2: 3-4, 3: 5, 4: 6-7). Primary endpoint was overall survival (OS). RESULTS: We included 268 patients with median age of 4 years. The analysis of the pS-GRAS score showed a significantly favorable prognosis in patients with a lower scoring compared to higher scoring groups (5-year OS: Group 1 98%; group 2 87% [hazard ratio {HR} of death 3.6, 95% CI of HR 1.6-8.2]; group 3 43% [HR of death 2.8, 95% CI 1.9-4.4]; group 4: OS 18% [HR of death 2.1, 95% CI 1.7-2.7]). In the multivariable analysis, age (HR of death 3.5, 95% CI 1.8-7.0), resection status (HR of death 5.5, 95% CI 2.7-11.1), tumor stage (HR of death 1.9, 95% CI of HR 1.2-3.0), and Ki67 index (HR of death 1.7, 95% CI 1.2-2.4) remained strong independent outcome predictors. Especially infants < 4 years showed more often low-risk constellations with a better OS for all tumor stages. CONCLUSION: In an international multicenter study, we confirmed that the pS-GRAS score is strongly associated with overall survival among patients with pACC. Age, resection status, stage, and Ki67 index are important parameters for risk stratification.

International consensus statement on the diagnosis and management of phaeochromocytoma and paraganglioma in children and adolescents.

Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumours that arise not only in adulthood but also in childhood and adolescence. Up to 70-80% of childhood PPGL are hereditary, accounting for a higher incidence of metastatic and/or multifocal PPGL in paediatric patients than in adult patients. Key differences in the tumour biology and management, together with rare disease incidence and therapeutic challenges in paediatric compared with adult patients, mandate close expert cross-disciplinary teamwork. Teams should ideally include adult and paediatric endocrinologists, oncologists, cardiologists, surgeons, geneticists, pathologists, radiologists, clinical psychologists and nuclear medicine physicians. Provision of an international Consensus Statement should improve care and outcomes for children and adolescents with these tumours.

Neuroendocrine tumors of the appendix in children and adolescents.

BACKGROUND: Neuroendocrine tumors (NET) of the appendix in children and adolescents are rare and mostly detected postoperatively by a histopathological examination. Since the malignant potential of these tumors remains unclear, therapeutic recommendations are not evidence based. The Society of Pediatric Oncology and Hematology (GPOH) has prospectively registered and followed children with appendical NET since 1997 (GPOH-MET trial). The objective of this study was to critically evaluate the therapeutic recommendations for appendical NET in children. PROCEDURE: Clinical data of 237 children with appendical NET were prospectively analyzed. RESULTS: The mean age at presentation was 13.0 years, while the mean follow-up time was 2.9 (0.0-12.8) years. The majority of tumors (70.9%) were located at the apex, and were smaller than or equal to 10 mm (72.7%). Tumor size was directly correlated with age. A second operation or primary lymph node sampling was done in 25.3% (N = 60) of the patients, and infiltration of the lymph nodes by tumor cells was found in nine of these patients (15%). All 237 patients are alive without tumor symptoms. CONCLUSIONS: ROC analysis and subsequent calculations identified a tumor size of >15 mm as the optimal cut-off point for the prediction of metastatic spread into the lymph system, with a sensitivity of 77.8% and a specificity of 66.7%. Therefore, secondary right hemicolectomy in completely removed appendical NET is recommended only in tumors >15 mm in size. For incompletely removed tumors ≤15 mm a local follow-up resection with lymph node sampling is recommended.

Time to diagnosis of brain tumors in children: a single-centre experience.

BACKGROUND: The aim of the study was to analyze the pre-diagnostic symptomatic interval (PSI) of children with brain tumors with regard to the parental and doctor's delay and the clinical symptoms. METHODS: A retrospective review of all children with brain tumors diagnosed in a single centre over a period of 11 years was carried out. RESULTS: Seventy-nine patients (35 boys, 44 girls), with a mean age of 9.2 years (0.2-23.5 years), were analyzed. PSI was 28 weeks with a parental delay of 11.1 weeks and a doctor's delay of 16.9 weeks. Main clinical symptoms were headache (66.7%), vomiting (57.7%), vision (46.2%) and gait (41.6) disorders and fatigue (41.0%) followed by other neurological signs. CONCLUSIONS: Diagnosis of pediatric brain tumors is often delayed in relation to the presenting symptoms. If parents report a combination of headache with other neurological abnormalities, a brain tumor should always be considered.

Bronchial carcinoid tumors in children and adolescents - A report and management considerations from the German MET studies.

OBJECTIVES: Bronchial carcinoid tumors (BC) are exceptionally rare in childhood, with an incidence of <0.2/1,000,000 per year. Typical low-grade BCs are distinguished from atypical, intermediate-grade BCs. Little is known about BCs in pediatric patients and management guidelines are missing. In this study, we explored characteristics and outcome of pediatric patients with BC prospectively registered with the Malignant Endocrine Tumor studies. MATERIAL AND METHODS: We performed a retrospective multicenter study in children, adolescents, and young adults (aged 0-20 years) with BC reported to the German MET registry between January 1997 and December 2022. Data were last updated on 28 of February 2023. RESULTS: Thirty-two patients were diagnosed at a median age of 15.0 years (range, 9.8-19.2). Atypical BCs (23.3%) were less frequent than typical, but more common than in adulthood. Lymph node metastases were present in 14.3% of cases (atypical BC: 28.6%, typical BC: 10.5%), distant metastases in one (3.1%) patient with atypical BC. 92.6% of patients were in complete remission after surgical resection (median follow-up: 2.7 years). The patient with metastatic spread and one patient with atypical BC and multiple recurrences were on treatment at last follow-up. 5-year event-free survival of typical BC was 100% and 83.3% in atypical BC. CONCLUSIONS: Completely resected localized BCs in pediatric patients have a favorable outcome also with lung tissue sparing surgery. Atypical BC with risk of metastatic spread and recurrence occurred more frequently compared to adults. Interdisciplinary management and collaborative efforts are needed to improve our understanding and the management of pediatric BC.

Locally Advanced Adrenocortical Carcinoma in Children and Adolescents-Enigmatic and Challenging Cases.

BACKGROUND: Locally advanced tumors account for approximately 50% of children and adolescents with adrenocortical carcinoma (ACC), and of these, up to 50% relapse. We explored the five-item microscopic score and the pS-GRAS score for guiding management. METHODS: Data from children and adolescents with COG stage II and III ACC registered in the MET studies were included. The five-item and pS-GRAS score were retrospectively calculated. RESULTS: By December 2021, 55 patients with stage II and III (stage II n = 18, stage III n = 37) had been reported. Median age was 4.3 years [0.1-17.8], median duration of follow-up 6.0 years [0-16.7]. 3-year event-free survival (EFS) rate was 76.5% and 49.8% (p = 0.088), respectively. In stage II tumors, neither the five-item score (p = 0.872) nor pS-GRAS grouping (p = 0.218) had any effect as prognostic factors. In stage III patients, EFS was impaired in tumors with unfavorable histology according to the five-item score (100% vs. 30.8%, p = 0.018). No difference was observed for pS-GRAS groups (p = 0.798). CONCLUSIONS: In patients with COG stage III, but not stage II, the five-item score affected EFS. Further studies are needed to identify patients at risk in COG stage II.

Sensitivity of fine-needle biopsy in detecting pediatric differentiated thyroid carcinoma.

BACKGROUND: Differentiated thyroid carcinomas (DTC) are uncommon in children. Since the frequency of malignancy is assumed to be high in pediatric symptomatic thyroid nodules, carcinomas should be ruled out reliably. The objective of this study was to assess the sensitivity of fine-needle biopsy (FNB) in diagnosing children with DTC. PROCEDURE: We retrospectively analyzed 15 years of data from the GPOH-MET registry, a database by the German Society for Pediatric Oncology and Hematology (GPOH) with a focus on malignant endocrine tumors (MET). We reviewed data on pediatric patients with DTC who had undergone FNB. FNB results were classified according to well-established guidelines. RESULTS: During the study period, 206 children with a histological diagnosis of DTC were entered into the GPOH-MET database. Fifty of those patients aged 3.6-17.3 years (mean, 12.3 years) had undergone FNB preoperatively. Forty-one were diagnosed with papillary thyroid carcinoma (PTC), seven with follicular thyroid carcinoma (FTC), and two had DTC not otherwise specified. Of the first FNB performed on each patient, the cytological specimens were diagnosed as benign in 13 cases, malignant in 14, suspicious in 9, follicular neoplasms in 6, and unsatisfactory in 8. The sensitivity of FNB in detecting DTC was 69.0%. CONCLUSIONS: Our results reflect the current practice of pediatric thyroid FNB in Germany. In order to improve its usefulness, FNB should always be performed by experienced physicians. Furthermore, a central review of all specimens is necessary to ascertain the validity of the cytological diagnosis and to introduce immunocytological and molecular methods.

Key factors for effective mitotane therapy in children with adrenocortical carcinoma.

Adjuvant treatment with mitotane and chemotherapy is recommended for paediatric advanced and metastatic adrenocortical carcinoma (ACC). Yet, questions on the indication, dosage, and length of therapy are unanswered. Data from the German Paediatric Oncology Haematology-Malignant Endocrine Tumour studies were analysed retrospectively for patients receiving mitotane during first- and/or second-line therapy. Forty-three patients were identified (median age: 7.5 years (range: 0.2-17.8); 29 female) with median follow-up of 2.2 years (range: 0.04-12.71). Three-year overall (OS) and progression-free survival (PFS) were 44.9% and 28.5%, respectively. Eleven of 43 patients received mitotane as neoadjuvant treatment, and 4/11 tumours reached partial remission (PR). Twenty-seven of 43 patients received mitotane combined with chemotherapy in an adjuvant setting resulting in PR of measurable target lesions in 5/13 patients. Metastatic disease (hazard ratio (HR): 3.2; 95% CI: 1.2-18.6; P = 0.018), duration of mitotane treatment <9 months (HR: 5.6; 95% CI: 1.9-16.9; P = 0.002), and not achieving drug target range (TR) (HR: 28.5; 95% CI: 5.4-150.3; P < 0.001) significantly impacted as negative prognostic factors upon PFS and OS (metastatic disease: HR: 4.9; 95% CI: 1.6-15.5; P = 0.006; duration of mitotane treatment: HR: 7.0: 95% CI 1.9-26.0; P = 0.004; TR not reached: HR: 13.5; 95% CI 3.6-50.3; P < 0.001). Cox regression determined the risk of event decreasing by 10.4% for each month of mitotane treatment (P = 0.015). Re-treatment with mitotane after first-line treatment proved ineffective. The duration of mitotane treatment and reaching mitotane TR significantly impacted survival. Improving the efficacy of mitotane, including appropriate indications, needs to be evaluated in prospective randomized trials.

Age, American Thyroid Association Risk Group, and Response to Therapy Are Prognostic Factors in Children With Differentiated Thyroid Cancer.

CONTEXT: Against the background of increasing incidence, pediatric differentiated thyroid carcinoma (DTC) frequently presents with advanced disease and high recurrence rates while prognosis remains excellent. BACKGROUND: We investigated the use of a pediatric classification and an adult response to therapy risk stratification for pediatric DTC patients and their implications for adaptation of treatment and follow-up. METHODS: Data from patients aged <18 years with a diagnosis of primary DTC, registered with the German Pediatric Oncology Hematology-Malignant Endocrine Tumor registry since 1995, were analyzed. For risk prediction, patients were retrospectively assigned to the American Thyroid Association (ATA) risk groups and evaluated for response to therapy. RESULTS: By October 2019, 354 patients with DTC had been reported (median age at diagnosis 13.7 years, range 3.6-17.9) with lymph node and distant metastases in 74.3% and 24.5%. Mean follow-up was 4.1 years (range 0-20.6). Ten-year overall and event-free survival (EFS) rates were 98.9% and 78.1%. EFS was impaired for patients with lymph node and distant metastases (P < .001), positive postoperative thyroglobulin (P = .006), incomplete resection (P = .002), sequential surgeries to achieve total thyroidectomy (P = .042), invasion of capsule (P < .001) and lymph vessels (P = .005), infiltration of surrounding soft tissues (P < .001), tumor multifocality (P < .001), ATA intermediate- and high-risk group (P < .001), and age <10 years (P < .001). Multivariate analysis revealed age <10 years at diagnosis, ATA high-risk level, and poor response to therapy as significant negative prognostic factors for EFS. CONCLUSION: Age, ATA risk group, and response to therapy emerged as significant prognostic factors for EFS in pediatric patients with DTC, requiring risk-adapted individualized therapy and follow-up.