Variations in Epithelial Lining of Duplication Cysts Cannot be Explained by Known Theories.

Objectives. Duplication cysts are found in any part of the gastrointestinal tract from the oropharynx to anus. Although duplication cysts usually have similar epithelium with the adjacent organ, respiratory epithelium in the enteric duplication cysts is rarely reported. This study was performed to evaluate the variations in the epithelial lining of duplication cysts and its clinical implications. Methods. Patients diagnosed with duplication cysts between 2012 and 2022 were retrospectively reviewed to assess their histopathological results, clinical aspects, treatment options, and demographic characteristics. Results. Twenty-five patients were included. The mean age was 4 years, male-to-female ratio was 15:10. The localizations of duplication cysts were ileum (n = 12), duodenum(n = 4), stomach(n = 3), jejunum(n = 2), colon(n = 2), thoracoabdominal(n = 2), and rectum(n = 1). Most common presentation was abdominal pain (36%). Intestinal (48%) and gastric (40%) epithelia were the most common finding. Four patients (16%) had respiratory epithelium: two in foregut duplication cysts, one each in ileal, and rectal duplications. Twenty-four percentage of patients had associated anomalies. Surgical interventions were performed on 22 patients. Conclusion. Duplication cysts show a wide range of epithelial linings. Respiratory epithelium can be found in not only foregut duplication cysts but also midgut and hindgut duplication cysts. Although the presence of respiratory epithelium did not have any impact on clinical findings, none of the previous theories explain the presence of respiratory epithelium different from foregut duplications.

Pulmonary involvement in children with Langerhans cell histiocytosis.

BACKGROUND: Pulmonary Langerhans cell histiocytosis (pLCH) is a rare disease, mostly a component of multisystemic LCH. We aimed to investigate the clinical features and treatment results in children with pLCH. METHODS: We retrospectively reviewed the clinical, radiological, and treatment data of 37 patients with pLCH, diagnosed from 1974 to 2022. RESULTS: 10% (n=37) of 367 patients with LCH had lung involvement. The median age was 1.8 years (range: 0.4 & 17.7) with a male-to-female ratio of 2.3. At admission 29.7% (n=11) presented with respiratory symptoms. Imaging showed a spectrum from nodular opacities to multiple cysts. All but one patient had multisystem disease. Twenty-nine received vinblastine-containing therapy. Ten-year event-free (EFS) and overall survival (OS) rates were 47.8% and 63.3%, respectively. In children younger and older than two years of age, the 10-year EFS was 53.3% vs. 40.2% and the 10-year OS was 58.7% vs. 68.8%, respectively. In children with and without risk organ involvement, 10-year EFS was 51.9% vs. 46.3% and 10-year OS was 51.9% vs. 73.7%. CONCLUSIONS: Lung and multisystem involvement are significant concerns in LCH, highlighting the need for careful management to reduce morbidity and mortality.

Further expanding the phenotype of anti-Ku antibody associated disease in children and adolescents.

Anti-Ku autoantibodies are associated with several autoimmune inflammatory diseases. We aimed to review our anti-Ku positive pediatric patients in this study. Four pediatric patients (all female) who had anti-Ku positivity were included (Patients 1-2-3 with idiopathic inflammatory myopathy (IIM); Patient 4 with chronic urticaria). Patient 1 (onset:10.5 years) had proximal muscle weakness, Raynaud phenomenon, sclerodactyly, hyperpigmentation, joint contracture, and tenosynovitis. The disease course was progressive despite treatment with corticosteroids, intravenous immunoglobulin (IVIG), plasma exchange, and 11 different immunosuppressive drugs. Patient 2 (onset:15 years) presented with proximal muscle weakness, fatigue, weight loss. She recovered normal muscle strength after treatment with corticosteroids, IVIG, methotrexate, cyclosporine A, mycophenolate mofetil. Patient 3 (onset:10 years) had juvenile dermatomyositis with proximal muscle weakness, Gottron's papules, and calcinosis. She also had anti-NXP2 positivity. Remission was achieved with corticosteroids, methotrexate, azathioprine, and infliximab. Muscle biopsy findings revealed a variable spectrum of necrosis, regeneration, perifascicular pattern, and inflammation. Patient 4 had only chronic urticaria (onset: 6.5 years). The striking features of this series were heterogeneity in clinical presentations including solely chronic urticaria and IIM; variable response to immunosuppressive treatments; and histopathology revealing a spectrum of necrosis, regeneration and inflammatory infiltration. Expanding the spectrum of anti-Ku positivity will allow better understanding of anti-Ku-associated phenotype clusters.

AP-1-dependent fibrosis: Exploring its potential role in the pathogenesis of placental transmogrification of the lung (PTL) via tissue-level transcriptome analysis.

Placental transmogrification of the lung (PTL) is a rare pulmonary condition characterized by the presence of immature placental villous structures. The etiology and molecular mechanisms underlying this disease remain largely unknown. This functional study aimed to identify the molecular signatures in the pathogenesis of PTL via comprehensive transcriptome analysis. Comparative transcriptomic assessment of PTL tissue and stromal cells showed differential expression of 257 genes in PTL tissue and 189 genes in stromal cells. Notably, several transcription factors and regulators, including FOSB, FOS, JUN, and ATF3, were upregulated in PTL tissue. Additionally, genes associated with the extracellular matrix and connective tissue, such as COL1A1, MMP2, and SPARC, were significantly altered, indicating possible fibrotic changes. Gene set enrichment analysis highlighted the role of vascular development and extracellular matrix organization, and the Activator Protein-1 (AP-1) transcription factor was significantly activated in PTL tissue. Furthermore, the analysis highlighted an overlap of 25 genes between PTL tissue and stromal cells, underscoring the importance of shared molecular pathways in the pathogenesis of PTL. Among the shared genes, JUND, COL4A2, COL6A2, IGFBP5, and IGFBP7 were consistently upregulated, highlighting the possible involvement of AP-1-mediated signaling and fibrotic changes in the pathogenesis of PTL. The present findings pave the way for further research into the molecular mechanisms underlying PTL and offer novel insights for therapeutic interventions. Given the rarity of PTL, these molecular findings represent a significant step forward in our understanding this enigmatic disease.

A Single-center Experience of Radiotherapy in Pediatric Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Chest Wall.

AIM: To evaluate the treatment results, prognostic parameters, and treatment-related toxicity in patients with Ewing sarcoma (ES)/primitive neuroectodermal tumor (PNET) of the chest wall who underwent surgery, chemotherapy, and radiotherapy (RT) in a tertiary referral center. METHODS: The data of 24 patients under 18 years of age with a histologic diagnosis of ES/PNET in the chest wall that received RT in our department between February 2003 and July 2020 were retrospectively evaluated. RT was applied to the primary site±whole involved chest wall and to the whole lung in patients with lung metastasis. RESULTS: The median age was 8.5 years (range: 1.5 to 17 y), 15 (63%) patients were female and 9 were male (37%). The tumor localization was extrathoracic in 18 (75%) and intrathoracic in 6 (25%) patients. Mediastinal lymph node and distant metastasis (DM) was present in 5 (21%) and 4 (16%) cases at diagnosis, respectively. The median follow-up after RT was 47 months (range: 11 to 162 mo). The 2-year and 5-year overall survival, event-free survival, local recurrence-free survival, and pleural recurrence-free survival were 83% and 48%, 48% and 42%, 74% and 48%, and 61% and 52%, respectively. The overall local control rate was 83% and the pleural control rate was 67%. RT was well tolerated, with 1 case of grade 3 acute dermatitis and 1 case of grade 3 subacute radiation pneumonitis. Late toxicity was observed in 3 (13%) cases. CONCLUSION: Long-term survival can be achieved with extended-field RT even in patients with ES/PNET of the chest wall with DM. The low toxicity rates allow us to draw the conclusion that RT with modern techniques is an effective and safe treatment modality for these patients.

Imaging Features of Pediatric Sarcoidosis.

Sarcoidosis is a granulomatous inflammatory disease of uncertain cause. It occurs most commonly in young and middle-aged adults and less frequently in children; therefore, few data on pediatric sarcoidosis exist in the literature. The diagnosis and management of sarcoidosis remain challenging because of diverse and often nonspecific clinical and imaging findings. In addition, the clinical picture varies widely by age. Prepubertal and adolescent patients often present with adult-like pulmonary disease; however, early-onset sarcoidosis is typically characterized by the triad of arthritis, uveitis, and skin rash. Sarcoidosis is mostly a diagnosis of exclusion made by demonstrating noncaseating granulomas at histopathologic examination in patients with compatible clinical and radiologic findings. Although sarcoidosis often affects the lungs and thoracic lymph nodes, it can involve almost any organ in the body. The most common radiologic manifestation is pulmonary involvement, characterized by mediastinal and bilateral symmetric hilar lymphadenopathies with perilymphatic micronodules. Abdominal involvement is also common in children and often manifests as hepatomegaly, splenomegaly, and abdominal lymph node enlargement. Although neurosarcoidosis and cardiac sarcoidosis are rare, imaging is essential to the diagnosis of central nervous system and cardiac involvement because of the risky biopsy procedure and its low diagnostic yield due to focal involvement. Being familiar with the spectrum of imaging findings of sarcoidosis may aid in appropriate diagnosis and management. ©RSNA, 2023 Test Your Knowledge questions are available in the supplemental material.