Objective:To explore the clinical and genetic characteristics of three children with 22q13 deletion syndrome. .Methods:Clinical data were collected and copy number variations in the patients and their parents were detected by using array-based comparative genomic hybridization (aCGH) and copy number variation sequencing (CNV-seq). The DECIPHER, ClinGen, OMIM, PubMed and Gene Review databases were retrieved for pathogenicity analysis. .Results:The common phenotypes of the three children have included variable global developmental delay, among which speech delay was the most obvious. Patient 1 had abnormalities of corpus callosum shown by magnetic resonance imaging. Patient 2 had dental crowding, pale skin, thick palms, hypotonia, and other facial features. Patient 3 had the mildest symptoms including language dysfunction, which has caught up with the development and improved significantly. All of the three children had harbored de novo deletions of 22q13.33q13.33 region, which spanned 0.84 Mb, 8.70 Mb and 0.90Mb and involved 37, 126, and 34 genes, respectively.Conclusion:Above finding has enriched the clinical and genetic characteristics of 22q13 deletion syndrome and laid a foundation for genetic counseling and prenatal diagnosis.

The basic information and clinical data of 4 Phelan-McDermid syndrome (PMS) patients in the Pediatric Outpatient Department of the Peking University First Hospital from January 2014 to October 2019 were retrospectively analyzed.Genetic diagnoses were performed using the whole exon sequencing assay.The genotype-phenotype correlation analysis was then performed.All patients presented with intellectual disability/developmental delay, especially the most-common manifestation in language disability.Patient 2 had an autism behavior.Four novel variations of the SHANK3 gene were found in this study, including the c. 2861delC p. (S955Pfs*109), c.3166delC p. (A1039Afs*39), c.3711_3723delGCCCAGCCCCCGG p. (L1241Lfs*29) and c. 2223+ 1G>A.All of them were analyzed as new pathogenic variations according to the American College of Medical Genetics and Genomics criteria.The present study expan-ded the mutant spectrum of the SHANK3 gene, which provided a basis for further accurate genetic counseling and prenatal diagnosis of PMS.

Objective:To analyze the dosimetric differences between gamma knife stereotactic body radiation therapy (SBRT) and linear accelerator-based SBRT for lung tumors by comparison to provide a theoretical basis for the selection of treatment strategies.Methods:Seven patients who underwent SBRT for lung tumors in the Cancer Center of Affiliated Zhongshan Hospital of Dalian University from January 2022 to May 2023 were enrolled. Plans of gamma knife SBRT (γ_SBRT) or linear accelerator-based SBRT plans (X_SBRT) were designed for the 13 lesions in the patients, with adjacent lesions in the same patient sharing one plan. As a result, 10 γ_SBRT plans and 10 X_SBRT plans were obtained. All lesions received 30-50 Gy of radiation in 5-10 fractions. Then, dosimetric parameters were analyzed and compared between γ_SBRT and X_SBRT plans, including the target coverage, gradient index (GI), conformity index (CI), maximum dose ( Dmax); mean dose ( Dmean), and minimum dose ( Dmin) of planning target volumes (PTVs); lung volumes receiving 20 Gy or more ( V20), 10 Gy or more ( V10), 5 Gy or more ( V5), 100% of the prescription dose ( V100%), and 50% of the prescription dose ( V50%); Dmean and the percentages of lung volume receiving doses of 20 Gy or more (Lung_ V20) and 5 Gy or more (Lung_ V5) of ipsilateral lung; Dmean and Lung_ V5 of contralateral lung; and Dmax values of the esophagus, spinal cord, and heart. Results:Compared to X_SBRT plans, γ_SBRT plans exhibited superior GI, V20, V10, V5, V50%, the Dmean, Lung_ V20, and Lung_ V5 of ipsilateral lung, the Dmean and Lung_ V5 of the contralateral lung, and the Dmax of esophageal and heart ( z = -2.81 to -1.99, P < 0.05), higher Dmax and Dmean of PTVs ( z = -2.80, -2.80, P < 0.05), and longer delivery time ( z=-2.70, P<0.05). Meanwhile, there was no significant difference in target coverage, CI, and Dmax of the spinal cord ( P > 0.05). Conclusions:Gamma knife SBRT plans can achieve sharper dose falloff outside target volumes than linear accelerator-based SBRT plans. Gamma knife radiosurgery is expected to reduce the radiation dose to low-dose areas around PTVs and normal lung tissue in SBRT for lung tumors. However, it significantly prolongs the delivery time.

A 6-year-old girl presented with recurrent skin rash at the initial stage, recent joint pain, and neutrophilia was found during a routine blood test. After a multidisciplinary case discussion, she was diagnosed with chronic neutrophil leukemia, and the symptoms were relieved after hydroxyurea and luxolitinib treatment. She received the allogeneic hematopoietic stem cell transplantation subsequently. At present, she is in stable condition and under follow-up. Chronic neutrophil leukemia is a rare disease, which rarely occurs in children. It is more difficult to diagnose in patients with skin rash as the first manifestation. The diagnosis and treatment of this case reflects the important role of multidisciplinary cooperation in the diagnosis and treatment of difficult and rare diseases.