Prognostic value of microRNA-125a expression status in molecular groups of pediatric medulloblastoma.

PURPOSE: Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Current treatment allows decent survival rates but often with life-long morbidity. Molecular classification provides a base for novel therapeutic approaches. However, these groups are heterogeneous. MicroRNA-125a has a tumor suppressor function. It is downregulated in several tumors. The expression of microRNA-125a in MB patients remains unclear. Therefore, this study was designed to evaluate the expression of microRNA-125a in molecular groups of pediatric MB patients in Egyptian population and its clinical significance. METHODS: Formalin-fixed, paraffin-embedded tissue blocks from 50 pediatric MB patients were retrospectively collected. Immunohistochemistry for ß-catenin, GAB1, YAP1, and p53 was done for molecular classification. MicroRNA-125a expression analysis was done using qRT-PCR. Follow-up data were obtained from patients' records. RESULTS: MicroRNA-125a expression was significantly lower in MB patients showing large cell/anaplastic (LC/A) histology and in the non-WNT/non-SHH group. Lower levels of microRNA-125a showed a tendency toward poor survival rates; however, difference was not significant. Infants and larger preoperative tumor size were significantly associated with lower survival rates. On a multivariate analysis, preoperative tumor size was an independent prognostic factor. CONCLUSION: MicroRNA-125a expression was significantly lower in categories of pediatric MB patients with worse prognosis namely LC/A histology and the non-WNT/non-SHH group suggesting a pathogenetic role. MicroRNA-125a expression could represent a promising prognostic factor and a potential therapeutic target in the non-WNT/non-SHH group which represents the most common and the most heterogeneous group of pediatric MBs coupled with the highest rates of disseminated disease. Preoperative tumor size represents an independent prognostic factor.

Effects of COVID-19 on Pediatric Cancer Care: A Multicenter Study of 11 Middle Eastern Countries.

During the COVID-19 pandemic, major challenges are facing pediatric cancer centers regarding access to cancer centers, continuity of the anti-cancer therapy, hospital admission, and infection protection precautions. Pediatric oncologists actively treating children with cancer from 29 cancer centers at 11 countries were asked to answer a survey from May 2020 to August 2020 either directly or through the internet. COVID-19 pandemic affected the access to pediatric cancer care in the form of difficulty in reaching the center in 22 (75.9%) centers and affection of patients' flow in 21 (72.4%) centers. Health care professionals (HCP) were infected with COVID-19 in 20 (69%) surveyed centers. Eighteen centers (62%) modified the treatment guidelines. Care of follow-up patients was provided in-hospital in 8(27.6%) centers, through telemedicine in 10 (34.5%) centers, and just delayed in 11 (38%) centers. Pediatric oncologists had different expectations about the future effects of COVID-19 on pediatric cancer care. Seventy-six percent of pediatric oncologists think the COVID-19 pandemic will increase the use of telemedicine. Fifty-five percent of pediatric oncologists think if the COVID-19 pandemic persists, we will need to change chemotherapy protocols to less myelosuppressive ones. Collaborative studies are required to prioritize pediatric cancer management during COVID-19 era.

Diffusion-weighted MRI and in-phase/opposed-phase sequences in the assessment of bone tumors.

PURPOSE: To evaluate the role of diffusion-weighted apparent diffusion coefficient (ADC) and in-phase/opposed-phase sequences in the differentiation of benign and malignant osseous tumors. MATERIALS AND METHODS: At 1.5T, routine sequences were compared to diffusion-weighted and in-phase/opposed-phase in 63 patients. Routine sequence magnetic resonance imaging (MRI) scoring, mean ADC value, and in-phase/opposed-phase signal intensity ratio (SIR) was obtained. Statistical analysis included significance, receiver operating characteristic (ROC), and linear correlation between the three parameters. RESULTS: In all, 38 patients had malignant tumors and 25 patients had benign tumors. Benign and malignant tumors showed different routine sequence scores (P < 0.001). Mean ADC of the benign lesions ranged 0.9-3.2 × 10(-3) mm(2) /sec of mean ± SD (1.9 ± 0.6). In malignant tumors, the mean ADC ranged 0.6-1.9 × 10(-3) mm(2) /sec of mean ± SD (1.1 ± 0.4) (P < 0.0001). There was a possible differentiation between malignant and benign tumors at a threshold of 1.1 × 10(-3) mm(2) /sec of sensitivity and specificity of 94.1% and 70.3%, respectively. SIR for benign tumors ranged 0.2-1.0 of mean ± SD (0.6 ± 0.3). For malignant lesions SIR ranged 0.4-1.2 of mean ± SD (0.8 ± 0.3). Benign and malignant tumors show statistically significant SIR at P < 0.022 with possible differentiation at a threshold of 0.75 of sensitivity and specificity of 70.3% and 76.5%, respectively. Simple linear correlation between both ADC and SIR was significant at P < 0.01 with correlation coefficient (r) = 0.45. CONCLUSION: Diffusion-weighted and in-phase/opposed-phase imaging might be used in addition to conventional MRI as a routine tool for differentiation of benign and malignant tumors. J. Magn. Reson. Imaging 2016;44:565-572.

Lymphadenopathy in a series of Egyptian pediatric patients and the role of pathology in the diagnostic workup.

Assessment of lymphadenopathy in children represents a diagnostic challenge because of the extensive differential diagnoses, including reactive and malignant conditions. Knowledge of the etiologic pattern of lymphadenopathy in a given geographical region is essential for making a confident diagnosis or for suspecting a disease. Hence, the present study was carried out to identify different etiologies of lymphadenopathy in children in our region and to assess parameters commonly associated with malignancy, with an emphasis on the role of pathology. One hundred and twenty patients aged 1 month to 18 years were included in the study. They were sorted into neoplastic and nonneoplastic (infectious and noninfectious) groups. In 56 patients, biopsy (fine needle aspiration cytology [FNAC], core needle, or excision biopsy) was essential to reach the final diagnosis. Sensitivity of FNAC in the differentiation between neoplastic and nonneoplastic lymphadenopathy was 92.3%, and specificity was 90.0%, with a diagnostic accuracy of 91.3%. We concluded that malignancy should be suspected in the following conditions: presence of abdominal or multiple symptoms; symptom duration of 1-6 months; generalized lymphadenopathy; multiple groups of lymph node (LN) involved; LN size > 2 cm; amalgamated, hard, fixed, and nontender LNs; certain abnormal complete blood count findings; blast cells in blood film; and elevated lactate dehydrogenase level. In such cases, LN biopsy is highly recommended. A final diagnosis was achieved after integrating information from history and clinical findings with the laboratory, radiological, pathological, and microbiological findings. Accordingly, an algorithm for primary diagnostic evaluation of children with lymphadenopathy is suggested.