Diagnosis and management of a sacrococcygeal teratoma at a tertiary hospital in northern Tanzania: A case report.

INTRODUCTION AND IMPORTANCE: Sacrococcygeal teratoma is a rare extragonadal germ cell tumor occurring at the lower end of the back. It is congenital, and can be diagnosed in utero or just after birth. These tumors are sporadic in nature, more common in females than in males. They can be solid, cystic or a mixture of the two in consistency. Authors present this case to share their experience because these congenital tumors are rare and a lapse in appropriate management can be devastating because of chances of recurrence and the possibility of a malignant nature of the disease. CASE PRESENTATION: Authors in this case present a baby that was referred to their center 5 days post vaginal delivery with a huge mass on the sacrococcygeal region. MRI revealed sacrococcygeal teratoma type II. Wide local excision was done. Tumor margins were microscopically negative. The patient recovered well and was discharged. The patient did not require adjuvant treatment. CLINICAL DISCUSSION: Routine obstetric ultrasound can diagnose sacrococcygeal teratoma with 100 % sensitivity. Fetuses with tumors <5 cm in size can be delivered vaginally. Tumors larger than that should be delivered at term through cesarean section. High risk sacrococcygeal teratomas can be delivered at 28 weeks of gestation by cesarean section followed by ex-utero intrapartum therapy. MRI is useful to assess the intrapelvic extent of the tumor and to plan management. Surgical intervention should be done after delivery. CONCLUSION: Intrauterine diagnosis is not an indication for termination of pregnancy. Surgical resection with negative margins provides a cure. Histological examination of the tumor is mandatory. For malignant sacrococcygeal teratomas, adjuvant chemotherapy is necessary for positive tumor margin after surgical resection. Positive margins may require chemotherapy. Neoadjuvant chemotherapy may be used for tumor debulking prior to surgery if the tumor infiltrates neighboring structures or is metastatic.

Neurologic recovery following laminectomy and tumor resection of a pediatric cervical synovial osteochondromatosis causing paralysis.

PURPOSE: To report the surgical outcome of synovial osteochondromatosis, a rare tumor of the cervical spine, in a 6-year-old boy. METHODS: A 6-year-old boy presented with muscle weakness in the right deltoid (2) and biceps (4) during a manual muscle test. Magnetic resonance imaging showed a 3 × 2 × 1.5 cm mass within the spinal canal at the C4-6 level, compressing the cervical spinal cord from the right side. Computed tomography revealed hyperintense areas within the tumor and ballooning of the right C4-5 and C5-6 facet joints. RESULTS: After a biopsy confirmed the absence of malignancy, a gross total resection was performed. The pathological diagnosis of synovial osteochondromatosis was established. Postoperatively, muscle weakness improved fully in the manual muscle test, and there were no neurological findings after 3 months. However, the patient is under careful follow-up owing to the detection of a regrowth site within the right C4-5 and C5-6 intervertebral foramen 2 years postoperatively. CONCLUSIONS: Synovial osteochondromatosis of the cervical spine in children is rare, and this is the first report of its regrowth after surgery. Synovial osteochondromatosis should be included in the differential diagnosis of pediatric cervical spine tumors.

Exploring the frontier in robotic pediatric cancer surgery: when to move forward and when to stop.

PURPOSE: In recent years, the use of robotic-assisted minimally invasive surgery in pediatric oncology has increased. Despite its benefits, its adoption remains limited. This single-center retrospective analysis examines technical nuances, indications, and surgical limitations to prevent complications. METHODS: Data from cancer patients treated robotically in 2015-2016 (Group A) and 2020-2022 (Group B) were compared. Decision-making considered tumor characteristics and risks, guided by multidisciplinary tumor board discussions. Data collected included demographics, intra/post-operative details, and tumor classifications. Statistical analysis evaluated influencing factors. RESULTS: Thirty-eight pediatric patients underwent robotic-assisted tumor resection, the median age was 5 years and weight 21.5 kg. Group A had higher median age and weight. Lesions included 23 malignant, 9 borderline, 5 benign cases; neuroblastoma (n = 19) was prevalent procedure and adrenalectomy was the predominant (28.94%). Open conversion occurred in 12 patients (31.58%), mainly due to vascular challenges (23.68%). Intraoperative complications were 10.53%, postoperative 7.9%. About 27% discharged by the third postoperative day; longer stays were needed for complex cases. All resumed post-op chemotherapy as scheduled, and all alive during follow-up. CONCLUSIONS: Our study confirms the safety and efficacy of robotic-assisted tumor resections in pediatric oncology, even during the learning phase, emphasizing the importance of learning curve, patient selection, and trocar positioning.

Integrated machine learning-driven disulfidptosis profiling: CYFIP1 and EMILIN1 as therapeutic nodes in neuroblastoma.

BACKGROUND: Neuroblastoma (NB), a prevalent pediatric solid tumor, presents formidable challenges due to its high malignancy and intricate pathogenesis. The role of disulfidptosis, a novel form of programmed cell death, remains poorly understood in the context of NB. METHODS: Gaussian mixture model (GMM)-identified disulfidptosis-related molecular subtypes in NB, differential gene analysis, survival analysis, and gene set variation analysis were conducted subsequently. Weighted gene co-expression network analysis (WGCNA) selected modular genes most relevant to the disulfidptosis core pathways. Integration of machine learning approaches revealed the combination of the Least absolute shrinkage and selection operator (LASSO) and Random Survival Forest (RSF) provided optimal dimensionality reduction of the modular genes. The resulting model was validated, and a nomogram assessed disulfidptosis characteristics in NB. Core genes were filtered and subjected to tumor phenotype and disulfidptosis-related experiments. RESULTS: GMM clustering revealed three distinct subtypes with diverse prognoses, showing significant variations in glucose metabolism, cytoskeletal structure, and tumor-related pathways. WGCNA highlighted the red module of genes highly correlated with disulfide isomerase activity, cytoskeleton formation, and glucose metabolism. The LASSO and RSF combination yielded the most accurate and stable prognostic model, with a significantly worse prognosis for high-scoring patients. Cytological experiments targeting core genes (CYFIP1, EMILIN1) revealed decreased cell proliferation, migration, invasion abilities, and evident cytoskeletal deformation upon core gene knockdown. CONCLUSIONS: This study showcases the utility of disulfidptosis-related gene scores for predicting prognosis and molecular subtypes of NB. The identified core genes, CYFIP1 and EMILIN1, hold promise as potential therapeutic targets and diagnostic markers for NB.

Extra-axial cerebellopontine angle nodular medulloblastoma mimicking meningioma: a case report with literature review.

Introduction: Medulloblastoma, a highly malignant embryonal tumor predominantly found in the pediatric population, typically arises within the cerebellum. This case report holds particular importance due to the rarity of medulloblastoma within the cerebellopontine angle (CPA). The distinct anatomical challenge posed by the CPA complex neurovascular structures, along with the absence of pathognomonic clinical or radiographic features, highlights the unique diagnostic and management challenge of this case. Case presentation: A 5-year-old boy presented with mild, progressively worsening headaches on CT/MRI imaging, which revealed a solid mass in the left CPA. Radiologically, the lesion closely resembled a CPA meningioma. The patient underwent a left retrosigmoid suboccipital craniectomy, utilizing a modified park bench position and careful burrhole creation. Intraoperatively, the tumor exhibited well-defined margins, firm adherence to cranial nerves, and complex tissue characteristics. Postoperatively, histopathological analysis identified nodular medulloblastoma, WHO grade IV, with immunohistochemical markers confirming its subtype. Discussion: This case highlights the critical role of surgical intervention in addressing rare tumors, emphasizing the need for multidisciplinary collaboration in both diagnosis and management to achieve a favorable outcome. Uncommon tumor locations, such as the CPA, require tailored approaches, and the utilization of advanced diagnostic techniques, including immunohistochemistry, aids in accurate subtype classification. Conclusion: This case highlights the critical role of surgical intervention in addressing rare tumors, emphasizing the need for multidisciplinary collaboration in both diagnosis and management to achieve a favorable outcome.

In vitro and in vivo modeling systems of supratentorial ependymomas.

Ependymomas are rare brain tumors that can occur in both children and adults. Subdivided by the tumors' initial location, ependymomas develop in the central nervous system in the supratentorial or infratentorial/posterior fossa region, or the spinal cord. Supratentorial ependymomas (ST-EPNs) are predominantly characterized by common driver gene fusions such as ZFTA and YAP1 fusions. Some variants of ST-EPNs carry a high overall survival rate. In poorly responding ST-EPN variants, high levels of inter- and intratumoral heterogeneity, limited therapeutic strategies, and tumor recurrence are among the reasons for poor patient outcomes with other ST-EPN subtypes. Thus, modeling these molecular profiles is key in further studying tumorigenesis. Due to the scarcity of patient samples, the development of preclinical in vitro and in vivo models that recapitulate patient tumors is imperative when testing therapeutic approaches for this rare cancer. In this review, we will survey ST-EPN modeling systems, addressing the strengths and limitations, application for therapeutic targeting, and current literature findings.

Primary Intraosseous Granular Cell Tumor of the Sphenoid and Central Skull Base in a Pediatric Patient.

BACKGROUND: Granular cell tumors occur in all ages and many anatomic sites. In the craniofacial region, they typically arise in soft tissue, not bone. We present a primary intra-osseous granular cell tumor of the sphenoid and central skull base arising in a 12- year- old girl. CASE REPORT: A 12-year-old female with sickle cell disease and Jeavons syndrome presented with seizures. Imaging and partial resection revealed an expansile benign granular cell tumor (GCT) involving the sphenoid body, pterygoid process, and central skull base. The disease has remained stable after 36-month follow up. DISCUSSION: GCT primarily involving the osseous sphenoid/skull base has not been previously reported in a child. Although mostly benign, some are aggressive, with malignant transformation in 1-2%. Surgery is the mainstay of treatment, but in the skull base this may be limited by adjacent critical structures. Decision-making is guided by anatomic extent, histology, and clinical behavior.

An analysis of muscle growth after proton beam therapy for pediatric cancer.

Retardation of growth and development is a well-known late effect after radiotherapy for pediatric patients. The goal of the study was to examine the effect of proton beam therapy (PBT) on the growth of muscles included in the irradiated area. The subjects were 17 pediatric patients (age ≤ 5 years) who received PBT with a treatment field including a muscle on only one side out of a pair of symmetrical bilateral muscles and had imaging evaluations for at least 1 year after PBT. The thicknesses of the irradiated and non-irradiated (contralateral) muscles were measured retrospectively on CT or MRI axial images collected before and after PBT. The change of thickness divided by the period (years) for each muscle was compared between the irradiated and contralateral sides. Correlations of muscle growth with irradiation dose and age at the start of treatment were also evaluated. The median observation period was 39.2 months. The measurement sites included the erector spinae (n = 9), gluteus maximus (n = 5) and rhomboids + trapezius (n = 3) muscles. The average changes in muscle thickness were 0.24 mm/year on the irradiated side and 1.19 mm/year on the contralateral side, showing significantly reduced growth on the irradiated side (P = 0.001). Younger patients had greater muscle growth. Irradiation dose was not significant, but muscle growth tended to decrease as the dose increased, and muscles irradiated at >50 Gy (RBE) showed little growth. These results show that muscle growth is affected by PBT and that long-term follow-up is needed to evaluate muscle growth retardation.

Scrotal epidermoid cysts penetrating the penile corpora cavernosa: Two case reports.

Introduction: Epidermoid cysts are tumors and that rarely occur in intrascrotal extratesticular tissues. It is extremely rare for the tumors to penetrate the penile corpora cavernosa. Case presentation: We encountered a 4-year-old and a 6-year-old boy with intrascrotal tumors that penetrated the penile corpora cavernosa. Both the patients underwent tumor resection. In the former case, some of the tumor within the corpora cavernosa was left behind, while in the latter case, the tumor was completely resected. Pathological examination in both cases confirmed the diagnosis of epidermoid cysts. Conclusion: We should consider the possibility of epidermoid cysts in children presenting with intrascrotal tumors. Moreover, care should be taken when handling the corpora cavernosa during surgery.

Thirty-day surgical morbidity and risk factors in pediatric brain tumor surgery: a 10-year nationwide retrospective study.

OBJECTIVE: Pediatric neuro-oncological surgery is often associated with significant risk; however, comprehensive data on surgical morbidity remain limited. The purpose of this study was therefore to provide national population-based data on both the incidence and characteristics of poor postoperative outcomes following pediatric intracranial neuro-oncological surgery. Additionally, the authors aimed to evaluate key risk factors for poor postoperative outcomes including overall morbidity, significant morbidity, and the most frequent types of morbidity. METHODS: The authors conducted a registry-based, nationwide, retrospective study including all children receiving surgical treatment for a CNS tumor over a 10-year period. Patients were identified using the Danish Childhood Cancer Registry, and 30-day morbidity was assessed through manual review of electronic health records. Significant morbidity was defined as complications in need of treatment under general anesthesia, ICU admission, or persistent neurological deficits at 30 days following surgery or death. Risk factors including sex, age, tumor location, tumor malignancy grade, and preoperative hydrocephalus were investigated using multivariate logistic regression analysis. RESULTS: A total of 349 children undergoing 473 tumor procedures were included, with an overall morbidity rate of 66.0% and a significant morbidity rate of 34.2%. The most frequent complications included neurological deficits (41.4%) and CSF-related morbidity consisting of CSF leaks, pseudomeningoceles, and postoperative hydrocephalus. Highly significant associations between infratentorial tumor location and both significant morbidity (OR 1.26, 95% CI 1.11-1.43; p < 0.001) and neurological deficits (OR 1.38, 95% CI 1.21-1.57; p < 0.001) were identified. In addition, younger age was revealed as a major risk factor of both postoperative CSF leakage and CSF-related morbidity in general. CONCLUSIONS: In this large, population-based cohort, the authors show that postoperative morbidity is frequent, occurring in about two-thirds of all patients, largely driven by neurological deficits and CSF-related complications. In addition, infratentorial tumor location and younger age emerged as key risk factors for poor postoperative outcomes.

A case of a pilocytic astrocytoma with histological features of anaplasia and unprecedent genetic alterations.

We report a case of pediatric glioma with uncommon imaging, morphological, and genetic features. A one-year-old boy incidentally presented with a tumor in the fourth ventricle. The tumor was completely resected surgically and investigated pathologically. The mostly circumscribed tumor had piloid features but primitive and anaplastic histology, such as increasing cellularity and mitosis. The Ki-67 staining index was 25% at the hotspot. KIAA1549::BRAF fusion and KIAA1549 partial deletions were detected by direct PCR, supported by Sanger sequencing. To the best of our knowledge, this is the first report of a glioma with both deletion of KIAA1549 p.P1771_P1899 and fusion of KIAA1549::BRAF. The tumor could not be classified using DNA methylome analysis. The present tumor fell into the category of pilocytic astrocytoma with histological features of anaplasia (aPA). Further studies are needed to establish pediatric aPA.

Expanding the Spectrum of EWSR1::CREM Fusion Tumors: An Unusual Pediatric Intranasal Myxoid Tumor.

EWSR1::CREM gene fusions are increasingly being recognized in a diverse number of soft tissue tumors, including well-defined entities such as angiomatoid fibrous histiocytoma or clear cell sarcoma, and other unclassifiable tumors. As a group, EWSR1::CREM fused tumors often demonstrate primitive spindle or epithelioid cells, myxoid stroma, and a broad immunophenotype. Herein we present an unusual case of a child diagnosed with an intranasal malignant myxoid tumor harboring an EWSR1::CREM gene fusion. To the best of our knowledge, this is the first case of intranasal myxoid tumor with this particular fusion. Diagnosis and management of the case is discussed.

Current Aspects of Intraoperative High-Field (3T) Magnetic Resonance Imaging in Pediatric Neurosurgery: Experiences from a Recently Launched Unit at a Tertiary Referral Center.

OBJECTIVE: To evaluate the neurosurgical and economic effectiveness of a newly launched intraoperative high-field (3T) magnetic resonance imaging (MRI) suite for pediatric tumor and epilepsy neurosurgery. METHODS: Altogether, 148 procedures for 124 pediatric patients (mean age, 8.7 years; range, 0-18 years) within a 2.5-year period were undertaken in a 2-room intraoperative MRI (iopMRI) suite. Surgery was performed mainly for intractable epilepsy (n = 81; 55%) or pediatric brain tumors (n = 65; 44%) in the supine (n = 113; 76%) and prone (n = 35; 24%) positions. The mean time of iopMRI from draping to re-surgery was 50 minutes. RESULTS: IopMRI was applied not in all but in 64 of 148 procedures (43%); in 45 procedures (31%), iopMRI was estimated unnecessary at the end of surgery based on the leading surgeon's decision. In the remaining 39 procedures (26%), ultra-early postoperative MRI was carried out after closure with the patient still sterile in the head coil. Of the 64 procedures with iopMRI, second-look surgery was performed in 26% (in epilepsy surgery in 17%, in tumor surgery in 9%). We did not encounter any infections, wound revisions, or position-related or anesthesiology-related complications. CONCLUSIONS: We used iopMRI in less than half of pediatric tumor and epilepsy surgery for which it was scheduled initially. Therefore, high costs argue against its routine use in pediatric neurosurgery, although it optimized surgical results in one quarter of patients and met high safety standards.

Clinicohistoradiological and surgical outcome in diffuse midline glioma.

PURPOSE: Diffuse Midline Glioma (DMG) with H3K27M mutation is a rare and aggressive midline high grade glioma with a predominant astrocytic differentiation and K27M mutation in either H3F3A or HIST1H3B/C. This tumor is more common in children than in adults. The current study was aimed to determine clinicohistoradiological and surgical outcome of patients who have undergone surgery for DMG and study disease severity of patients with DMG. METHODS: This is an observational study in which 29 DMG patients were evaluated for clinicohistoradiological and surgical outcomes by assessing the pre and postoperative neurological status. RESULT: Survival duration was significantly high in patients with age > 18 years (p = 0.02). Patients who had undergone Radiation Therapy showed higher survival rate (p = 0.05) and the cases with low levels of Ki 67 index had improved post operative outcome (p = 0.002). CONCLUSION: DMG with H3K27M mutation in newly classified Central Nervous System tumor are WHO grade IV Tumors, comprising H3K27M mutation as molecular marker for diagnosis and related with a poor prognosis.

A Rare Case of Pediatric Oropharyngeal Schwannoma.

This is a case of a male child who presented with a progressively enlarging oropharyngeal mass, hyponasal voice, and symptoms of obstructive sleep apnea. Computed tomography imaging of the head and neck revealed a well-circumscribed low-density area of polypoid morphology arising from the left lateral pharyngeal wall, filling most of the posterior oropharynx and extending to a pedicle at the lateral nasopharynx. Histopathological evaluation following surgical excision revealed Antoni A tissue and S100 immunoreactivity. The presentation and diagnosis of benign schwannoma neoplasms are discussed.

Deciphering pathological behavior of pediatric medullary thyroid cancer from single-cell perspective.

Background: Pediatric medullary thyroid cancer (MTC) is one of the rare pediatric endocrine neoplasms. Derived from C cells of thyroid glands, MTC is more aggressive and more prompt to metastasis than other types of pediatric thyroid cancer. The mechanism remains unclear. Methods: We performed single-cell transcriptome sequencing on the samples of the primary tumor and metastases lymph nodes from one patient diagnosed with MTC, and it is the first single-cell transcriptome sequencing data of pediatric MTC. In addition, whole exome sequencing was performed and peripheral blood was regarded as a normal reference. All cells that passed quality control were merged and analyzed in R to discover the association between tumor cells and their microenvironment as well as tumor pathogenesis. Results: We first described the landscape of the single-cell atlas of MTC and studied the interaction between the tumor cell and its microenvironment. C cells, identified as tumor cells, and T cells, as the dominant participant in the tumor microenvironment, were particularly discussed in their development and interactions. In addition, the WES signature of tumor cells and their microenvironment were also described. Actively immune interactions were found, indicating B cells, T cells and myeloid cells were all actively participating in immune reaction in MTC. T cells, as the major components of the tumor microenvironment, proliferated in MTC and could be divided into clusters that expressed proliferation, immune effectiveness, and naive markers separately.

Technical Note: Advantages of a 2-Room Intraoperative 3-Tesla Magnetic Resonance Imaging Operating Suite for Performing Laser Interstitial Thermal Therapy in Pediatric Epilepsy and Tumor Surgery.

OBJECTIVE: Magnetic resonance thermography-guided laser interstitial thermal therapy (LITT) provides a minimally invasive treatment option in children with central nervous system tumors or medically intractable epilepsy. However, transporting anesthetized children between an operating room (OR) and a radiologic suite creates logistical challenges. Thus we describe advantages of using a 2-room intraoperative magnetic resonance imaging (MRI) concept for LITT. METHODS: Patients were pinned in a head frame that doubles as the lower part of the MRI head coil. Preoperative MRI was performed for accurate neuronavigation, after which laser fibers were stereotactically implanted. Transport between OR and MRI was achieved by sliding the top of the OR table onto a trolly. RESULTS: We performed 12 procedures in 11 children, mean age 7.1 years (range: 2 to 14 years). Ten children suffered from medically intractable epilepsy, and 1 child had a pilocytic midbrain astrocytoma. Two fibers were placed in 8 and 1 fiber in 4 procedures. Mean entry point and target errors were 2.8 mm and 3.4 mm, respectively. Average transfer time from OR to MRI and vice versa was 9 minutes (±1 minute, 40 seconds). Altogether, 50% of the seizure patients were seizure free (Engel grade I) at 22 months' follow-up time. One hemorrhagic event, which could be managed nonoperatively, occurred. We recorded no surgical site or intracranial infections. CONCLUSIONS: All LITT procedures were successfully carried out with head frame in the sterile environment. The intraoperative MRI suite proved to be advantageous for minimally invasive procedures, especially in young children resulting in short transports while maintaining high accuracy and safety.

Atypical Pediatric Presentation of Pilomatricoma.

Pilomatricomas are uncommon, benign tumors of the hair follicle, which are often misdiagnosed upon initial inspection. Here we describe the case of a 4-year-old boy who presented with a persistent draining tumor on the left side of his neck for approximately two years. The tumor was originally misdiagnosed as scrofuloderma but, eventually, our patient's pilomatricoma was identified with biopsy and successfully treated with elliptical excision. We discuss the importance of considering pilomatricoma in the differential diagnosis.

STK11 Adnexal Tumor in an Adolescent Female: Diagnostic Pitfalls of a Recently Described Entity.

STK11 adnexal tumor is a recently described entity with less than 25 cases reported to date. These aggressive tumors typically occur in paratubal/paraovarian soft tissues, have characteristically striking morphologic and immunohistochemical heterogeneity, and harbor pathognomonic alterations in STK11. These occur almost exclusively in adult patients, with only one reported in a pediatric patient (to our knowledge). A previously healthy 16-year-old female presented with acute abdominal pain. Imaging studies revealed large bilateral solid and cystic adnexal masses, ascites, and peritoneal nodules. Following frozen section evaluation of a left ovarian surface nodule, bilateral salpingo-oophorectomy and tumor debulking were performed. Histologically, the tumor demonstrated distinctively variable cytoarchitecture, myxoid stroma, and mixed immunophenotype. A next generation sequencing-based assay identified a pathogenic STK11 mutation. We report the youngest patient to date with an STK11 adnexal tumor, highlighting key clinicopathologic and molecular features in order to contrast them with those of other pediatric intra-abdominal malignancies. This rare and unfamiliar tumor poses a considerable diagnostic challenge and requires a multidisciplinary integrated approach to diagnosis.