Lateralized overgrowth with vascular malformation caused by a somatic PTPN11 pathogenic variant: Another piece added to the puzzle of mosaic RASopathies.

Lateralized/segmental overgrowth disorders (LOs) encompass a heterogeneous group of congenital conditions with excessive body tissue growth. Documented molecular alterations in LOs mostly consist of somatic variants in genes of the PI3KCA/AKT/mTOR pathway or of chromosome band 11p15.5 imprinted region anomalies. In some cases, somatic pathogenic variants in genes of the RAS/MAPK pathway have been reported. We present the first case of a somatic pathogenic variant (T507K) in PTPN11 causing a LO phenotype characterized by severe lateralized overgrowth, vascular proliferation, and cerebral astrocytoma. The T507K variant was detected in DNA from overgrown tissue in a leg with capillary malformation. The astrocytoma tissue showed a higher PTPN11 variant allele frequency. A pathogenic variant in FGFR1 was also found in tumor tissue, representing a second hit on the RAS/MAPK pathway. These findings indicate that RAS/MAPK cascade overactivation can cause mosaic overgrowth phenotypes resembling PIK3CA-related overgrowth disorders (PROS) with cancer predisposition and are consistent with the hypothesis that RAS/MAPK hyperactivation can be involved in the pathogenesis of astrocytoma. This observation raises the issue of cancer predisposition in patients with RAS/MAPK pathway gene variants and expands genotype spectrum of LOs and the treatment options for similar cases through inhibition of the RAS/MAPK oversignaling.

Treatment and outcome of intracranial ependymoma after first relapse in the 2nd AIEOP protocol.

BACKGROUND: More than 40% of patients with intracranial ependymoma need a salvage treatment within 5 years after diagnosis, and no standard treatment is available as yet. We report the outcome after first relapse of 64 patients treated within the 2nd AIEOP protocol. METHODS: We considered relapse sites and treatments, that is, various combinations of complete/incomplete surgery, if followed by standard or hypofractionated radiotherapy (RT) ± chemotherapy (CT). Molecular analyses were available for 38/64 samples obtained at first diagnosis. Of the 64 cases, 55 were suitable for subsequent analyses. RESULTS: The median follow-up was 147 months after diagnosis, 84 months after first relapse, 5-year EFS/OS were 26.2%/30.8% (median EFS/OS 13/32 months) after relapse. For patients with a local relapse (LR), the 5-year cumulative incidence of second LRs was 51.6%, with a 5-year event-specific probability of being LR-free of 40.0%. Tumor site/grade, need for shunting, age above/below 3 years, molecular subgroup at diagnosis, had no influence on outcomes. Due to variation in the RT dose/fractionation used and the subgroup sizes, it was not possible to assess the impact of the different RT modalities. Multivariable analyses identified completion of surgery, the absence of symptoms at relapse, and female sex as prognostically favorable. Tumors with a 1q gain carried a higher cumulative incidence of dissemination after first relapse. CONCLUSIONS: Survival after recurrence was significantly influenced by symptoms and completeness of surgery. Only a homogeneous protocol with well-posed, randomized questions could clarify the numerous issues, orient salvage treatment, and ameliorate prognosis for this group of patients.

Development and application of a diagnostic and severity scale to grade post-operative pediatric cerebellar mutism syndrome.

The post-operative pediatric cerebellar mutism syndrome (CMS) affects about one-third of children and adolescents following surgical removal of a posterior fossa tumor (PFT). According to the Posterior Fossa Society consensus working definition, CMS is characterized by delayed-onset mutism/reduced speech and emotional lability after cerebellar or 4th ventricle tumor surgery in children, and is frequently accompanied by additional features such as hypotonia and oropharyngeal dysfunction/dysphagia. The main objective of this work was to develop a diagnostic scale to grade CMS duration and severity. Thirty consecutively referred subjects, aged 1-17 years (median 8 years, IQR 3-10), were evaluated with the proposed Post-Operative Pediatric CMS Survey after surgical resection of a PFT and, in case of CMS, for 30 days after the onset (T0) or until symptom remission. At day 30 (T1), CMS was classified into mild, moderate, or severe according to the proposed scale. CMS occurred in 13 patients (43%, 95% C.I.: 25.5-62.6%), with mild severity in 4 cases (31%), moderate in 4 (31%), and severe in 5 (38%). At T1, longer symptom persistence was associated with greater severity (p = 0.01). Greater severity at T0 predicted greater severity at T1 (p = 0.0001). Children with a midline tumor location and those aged under 5 years at diagnosis were at higher risk of CMS (p = 0.025 and p = 0.008, respectively). In conclusion, the proposed scale is a simple and applicable tool for estimating the severity of CMS at its onset, monitoring its course over time, and providing an early prognostic stratification to guide treatment decisions.

Pediatric diffuse midline glioma H3K27- altered: A complex clinical and biological landscape behind a neatly defined tumor type.

The 2021 World Health Organization Classification of Tumors of the Central Nervous System, Fifth Edition (WHO-CNS5), has strengthened the concept of tumor grade as a combination of histologic features and molecular alterations. The WHO-CNS5 tumor type "Diffuse midline glioma, H3K27-altered," classified within the family of "Pediatric-type diffuse high-grade gliomas," incarnates an ideally perfect integrated diagnosis in which location, histology, and genetics clearly define a specific tumor entity. It tries to evenly characterize a group of neoplasms that occur primarily in children and midline structures and that have a dismal prognosis. Such a well-defined pathological categorization has strongly influenced the pediatric oncology community, leading to the uniform treatment of most cases of H3K27-altered diffuse midline gliomas (DMG), based on the simplification that the mutation overrides the histological, radiological, and clinical characteristics of such tumors. Indeed, multiple studies have described pediatric H3K27-altered DMG as incurable tumors. However, in biology and clinical practice, exceptions are frequent and complexity is the rule. First of all, H3K27 mutations have also been found in non-diffuse gliomas. On the other hand, a minority of DMGs are H3K27 wild-type but have a similarly poor prognosis. Furthermore, adult-type tumors may rarely occur in children, and differences in prognosis have emerged between adult and pediatric H3K27-altered DMGs. As well, tumor location can determine differences in the outcome: patients with thalamic and spinal DMG have significantly better survival. Finally, other concomitant molecular alterations in H3K27 gliomas have been shown to influence prognosis. So, when such additional mutations are found, which one should we focus on in order to make the correct clinical decision? Our review of the current literature on pediatric diffuse midline H3K27-altered DMG tries to address such questions. Indeed, H3K27 status has become a fundamental supplement to the histological grading of pediatric gliomas; however, it might not be sufficient alone to exhaustively define the complex biological behavior of DMG in children and might not represent an indication for a unique treatment strategy across all patients, irrespective of age, additional molecular alterations, and tumor location.

Merkel Cell Carcinoma: Evaluation of the Clinico-Pathological Characteristics, Treatment Strategies and Prognostic Factors in a Monocentric Retrospective Series (n=143).

BACKGROUND: Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of the skin. The incidence of the disease has undergone a significant increase in recent years, which is caused by an increase in the average age of the population and in the use of immunosuppressive therapies. MCC is an aggressive pathology, which metastasizes early to the lymph nodes. These characteristics impose an accurate diagnostic analysis of the regional lymph node district with radiography, clinical examination and sentinel node biopsy. In recent years, there has been a breakthrough in the treatment of the advanced pathology thanks to the introduction of monoclonal antibodies acting on the PD-1/PD-L1 axis. This study aimed to describe the clinico-pathological characteristics, treatment strategies and prognostic factors of MCC. METHODS: A retrospective cohort study was conducted involving 143 consecutive patients who were diagnosed and/or treated for MCC. These patients were referred to the Veneto Institute of Oncology IOV-IRCCS and to the University Hospital of Padua (a third-level center) in the period between December 1991 and January 2020. In the majority of cases, diagnosis took place at the IOV. However, some patients were diagnosed elsewhere and subsequently referred to the IOV for a review of the diagnosis or to begin specific therapeutic regimens. RESULTS: 143 patients, with an average age of 71 years, were affected mainly with autoimmune and neoplastic comorbidities. Our analysis has shown that age, autoimmune comorbidities and the use of therapy with immunomodulating drugs (which include corticosteroids, statins and beta-blockers) are associated with a negative prognosis. In this sense, male sex is also a negative prognostic factor. CONCLUSIONS: Autoimmune and neoplastic comorbidities were frequent in the studied population. The use of drugs with immunomodulatory effects was also found to be a common feature of the population under examination. The use of this type of medication is considered a negative prognostic factor. The relevance of a multidisciplinary approach to the patient with MCC is confirmed, with the aim of assessing the risks and benefits related to the use of immunomodulating therapy in the individual patient.

Second series by the Italian Association of Pediatric Hematology and Oncology of children and adolescents with intracranial ependymoma: an integrated molecular and clinical characterization with a long-term follow-up.

BACKGROUND: A prospective 2002-2014 study stratified 160 patients by resection extent and histological grade, reporting results in 2016. We re-analyzed the series after a median of 119 months, adding retrospectively patients' molecular features. METHODS: Follow-up of all patients was updated. DNA copy number analysis and gene-fusion detection could be completed for 94/160 patients, methylation classification for 68. RESULTS: Progression-free survival (PFS) and overall survival (OS) at 5/10 years were 66/58%, and 80/73%. Ten patients had late relapses (range 66-126 mo), surviving after relapse no longer than those relapsing earlier (0-5 y). On multivariable analysis a better PFS was associated with grade II tumor and complete surgery at diagnosis and/or at radiotherapy; female sex and complete resection showed a positive association with OS. Posterior fossa (PF) tumors scoring ≥0.80 on DNA methylation analysis were classified as PFA (n = 41) and PFB (n = 9). PFB patients had better PFS and OS. Eighteen/32 supratentorial tumors were classified as RELA, and 3 as other molecular entities (anaplastic PXA, LGG MYB, HGNET). RELA had no prognostic impact. Patients with 1q gain or cyclin-dependent kinase inhibitor 2A (CDKN2A) loss had worse outcomes, included significantly more patients >3 years old (P = 0.050) and cases of dissemination at relapse (P = 0.007). CONCLUSIONS: Previously described prognostic factors were confirmed at 10-year follow-up. Late relapses occurred in 6.2% of patients. Specific molecular features may affect outcome: PFB patients had a very good prognosis; 1q gain and CDKN2A loss were associated with dissemination. To draw reliable conclusions, modern ependymoma trials need to combine diagnostics with molecular risk stratification and long-term follow-up.

The Italian consensus conference on the role of rehabilitation for children and adolescents with leukemia, central nervous system, and bone tumors, part 1: Review of the conference and presentation of consensus statements on rehabilitative evaluation of motor aspects.

Because of increasing survival rates in pediatric oncology, attention is focusing on cancer and its treatment-related side effects. Rehabilitation may reduce their impact. However, the literature does not provide strong evidence regarding rehabilitation pathways. Therefore, the Italian Association of Pediatric Hematology and Oncology organized a consensus conference on the role of rehabilitation of motor impairments in children/adolescents affected by leukemia, central nervous system, and bone tumors to define recommendations for daily practice. The grading of recommendation assessment, developing and evaluation (GRADE) method was used in order to formulate questions, select outcomes, evaluate evidence, and create recommendations. This paper includes the results on the rehabilitation assessment.

Comparison Between 18F-Dopa and 18F-Fet PET/CT in Patients with Suspicious Recurrent High Grade Glioma: A Literature Review and Our Experience.

PURPOSES: The aims of the present study were to: 1- critically assess the utility of L-3,4- dihydroxy-6-18Ffluoro-phenyl-alanine (18F-DOPA) and O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET) Positron Emission Tomography (PET)/Computed Tomography (CT) in patients with high grade glioma (HGG) and 2- describe the results of 18F-DOPA and 18F-FET PET/CT in a case series of patients with recurrent HGG. METHODS: We searched for studies using the following databases: PubMed, Web of Science and Scopus. The search terms were: glioma OR brain neoplasm and DOPA OR DOPA PET OR DOPA PET/CT and FET OR FET PET OR FET PET/CT. From a mono-institutional database, we retrospectively analyzed the 18F-DOPA and 18F-FET PET/CT of 29 patients (age: 56 ± 12 years) with suspicious for recurrent HGG. All patients underwent 18F-DOPA or 18F-FET PET/CT for a multidisciplinary decision. The final definition of recurrence was made by magnetic resonance imaging (MRI) and/or multidisciplinary decision, mainly based on the clinical data. RESULTS: Fifty-one articles were found, of which 49 were discarded, therefore 2 studies were finally selected. In both the studies, 18F-DOPA and 18F-FET as exchangeable in clinical practice particularly for HGG patients. From our institutional experience, in 29 patients, we found that sensitivity, specificity and accuracy of 18F-DOPA PET/CT in HGG were 100% (95% confidence interval- 95%CI - 81-100%), 63% (95%CI: 39-82%) and 62% (95%CI: 39-81%), respectively. 18F-FET PET/CT was true positive in 4 and true negative in 4 patients. Sensitivity, specificity and accuracy for 18F-FET PET/CT in HGG were 100%. CONCLUSION: 18F-DOPA and 18F-FET PET/CT have a similar diagnostic accuracy in patients with recurrent HGG. However, 18F-DOPA PET/CT could be affected by inflammation conditions (false positive) that can alter the final results. Large comparative trials are warranted in order to better understand the utility of 18F-DOPA or 18F-FET PET/CT in patients with HGG.

Pediatric intracranial ependymoma: correlating signs and symptoms at recurrence with outcome in the second prospective AIEOP protocol follow-up.

PURPOSE: The aims of patients' radiological surveillance are to: ascertain relapse; apply second-line therapy; accrue patients in phase 1/2 protocols if second-line therapy is not standardized/curative; and assess/treat iatrogenic effects. To lessen the emotional and socioeconomic burdens for patients and families, we ideally need to establish whether scheduled radiological surveillance gives patients a better outcome than waiting for symptoms and signs to appear. METHODS: We analyzed a prospective series of 160 newly-diagnosed and treated pediatric/adolescent patients with intracranial ependymoma, comparing patients with recurrent disease identified on scheduled MRI (the RECPT group; 34 cases) with those showing signs/symptoms of recurrent disease (the SYMPPT group; 16 cases). The median follow-up was 67 months. RESULTS: No significant differences emerged between the two groups in terms of gender, age, tumor grade/site, shunting, residual disease, or type of relapse (local, distant, or concomitant). The time to relapse (median 19 months; range 5-104) and the MRI follow-up intervals did not differ between the SYMPPT and RECPT groups. The presence of signs/symptoms was an unfavorable factor for overall survival (OS) after recurrence (5-year OS: 8% vs. 37%, p = 0.001). On multivariable analysis, an adjusted model confirmed a significantly worse OS in the SYMPPT than in the RECPT patients. CONCLUSIONS: Symptomatic relapses carried a significantly worse survival for ependymoma patients than recurrences detected by MRI alone. It would therefore be desirable to identify recurrences before symptoms develop. Radiological follow-up should be retained in ependymoma patient surveillance because there is a chance of salvage treatment for relapses found on MRI.

Final results of the second prospective AIEOP protocol for pediatric intracranial ependymoma.

BACKGROUND: This prospective study stratified patients by surgical resection (complete = NED vs incomplete = ED) and centrally reviewed histology (World Health Organization [WHO] grade II vs III). METHODS: WHO grade II/NED patients received focal radiotherapy (RT) up to 59.4 Gy with 1.8 Gy/day. Grade III/NED received 4 courses of VEC (vincristine, etoposide, cyclophosphamide) after RT. ED patients received 1-4 VEC courses, second-look surgery, and 59.4 Gy followed by an 8-Gy boost in 2 fractions on still measurable residue. NED children aged 1-3 years with grade II tumors could receive 6 VEC courses alone. RESULTS: From January 2002 to December 2014, one hundred sixty consecutive children entered the protocol (median age, 4.9 y; males, 100). Follow-up was a median of 67 months. An infratentorial origin was identified in 110 cases. After surgery, 110 patients were NED, and 84 had grade III disease. Multiple resections were performed in 46/160 children (28.8%). A boost was given to 24/40 ED patients achieving progression-free survival (PFS) and overall survival (OS) rates of 58.1% and 68.7%, respectively, in this poor prognosis subgroup. For the whole series, 5-year PFS and OS rates were 65.4% and 81.1%, with no toxic deaths. On multivariable analysis, NED status and grade II were favorable for OS, and for PFS grade II remained favorable. CONCLUSIONS: In a multicenter collaboration, this trial accrued the highest number of patients published so far, and results are comparable to the best single-institution series. The RT boost, when feasible, seemed effective in improving prognosis. Even after multiple procedures, complete resection confirmed its prognostic strength, along with tumor grade. Biological parameters emerging in this series will be the object of future correlatives and reports.

End-of-life care in pediatric neuro-oncology.

BACKGROUND: The management of children with cancer during the end-of-life (EOL) period is often difficult and requires skilled medical professionals. Patients with tumors of the central nervous system (CNS) with relapse or disease progression might have additional needs because of the presence of unique issues, such as neurological impairment and altered consciousness. Very few reports specifically concerning the EOL period in pediatric neuro-oncology are available. PROCEDURE: Among all patients followed at our center during the EOL, we retrospectively analyzed data from 39 children and adolescents with brain tumors, in order to point out on their peculiar needs. RESULTS: Patients were followed-up for a median time of 20.1 months. Eighty-two percent were receiving only palliative therapy before death. Almost half the patients (44%) died at home, while 56% died in a hospital. Palliative sedation with midazolam was performed in 58% of cases; morphine was administered in 51.6% of cases. No patient had uncontrolled pain. CONCLUSIONS: The EOL in children with advanced CNS cancer is a period of active medical care. Patients may develop complex neurological symptoms and often require long hospitalization. We organized a network-based collaboration among the reference pediatric oncology center, other pediatric hospitals and domiciliary care personnel, with the aim to ameliorate the quality of care during the EOL period. In our cohort, palliative sedation was widely used while no patients died with uncontrolled pain. A precise process of data collection and a better sharing of knowledge are necessary in order to improve the management of such patients.

Diffuse intrinsic pontine glioma in children and adolescents: a single-center experience.

BACKGROUND: Patients with diffuse intrinsic pontine glioma (DIPG) have a very poor prognosis. Only radiotherapy (XRT) has proven to be effective in delaying the disease progression. Several chemotherapy schedules have been applied so far, but none demonstrated significant improvements in progression and survival. METHODS: We retrospectively analyzed the clinical data of children diagnosed with DIPG at our center (Pediatric Hospital "Regina Margherita," Turin, Italy) between 1999 and 2013. Progression-free survival (PFS) and overall survival (OS) were used to describe the outcomes. RESULTS: Twenty-four children were included in our report. Patients diagnosed before March 2003 (n = 12) were treated with XRT and vincristine (VCR); the remaining 12 patients received XRT and temozolomide (TMZ). Progression-free survival was 18.8 % at 1 year (SE = 7.6 %), while overall survival was 44.1 % at 1 year (SE = 9.9 %). Median PFS was 8.1 months, whereas median OS was 11.2 months. No statistically significant difference in PFS or OS was evidenced between the two treatment groups. CONCLUSION: Radiotherapy followed by VCR or TMZ allows obtaining results that are in line with previous reports, with no advantages over other similar treatment schedules. DIPGs are challenging tumors with a dismal outcome. Further research and newer therapies are urgently needed in order to achieve improvements in survival.

Analysis of different medulloblastoma histotypes by two-dimensional gel and MALDI-TOF.

OBJECTIVE: The purpose of this study is to detect different protein profiles in medulloblastoma (MDB) that may be clinically relevant and to check the correspondence of histological classification of MDB with proteomic profiles. MATERIALS AND METHODS: Surgical specimens, snap frozen at the time of neurosurgery, entered the proteomic study. Eight samples from patients (age range, 4 months-26 years) with different MDB histotypes (five classic, one desmoplastic/nodular, one with extensive nodularity, and one anaplastic) were analyzed by two-dimensional gel electrophoresis. One sample for each histotype was further characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis. RESULTS: Eighty-six unique proteins were identified and compared to histology, with the determination of proteins expressed by single histotypes and of a smaller number of proteins shared by two or three histotypes. The sharp difference of protein expression was found to be in agreement with WHO histological classification, with the identification of type-specific proteins with limited overlapping between histotypes. CONCLUSION: Proteomic analysis confirmed and strengthened the difference between histotypes as biologically relevant. Cluster analysis enhanced the distance of extensive nodularity MDB from other histotypes. Possible innovative approaches to therapy may rely upon a proteomic-based classification of MDB tightly correlated to histology. The utility of snap freezing tumoral samples must be stressed and should become a mandatory task for pathologists.

Infant ependymoma in a 10-year AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica) experience with omitted or deferred radiotherapy.

PURPOSE: The protocols of the 1990s omitted or delayed irradiation, using upfront chemotherapy to spare the youngest children with ependymoma the sequelae of radiotherapy (RT). We treated 41 children under the age of 3 years with intracranial ependymoma between 1994 and 2003. PATIENTS AND METHODS: After surgery, chemotherapy was given as follows: regimen I with four blocks of vincristine, high-dose methotrexate 5 g/m(2), and cyclophosphamide 1.5 g/m(2) alternating with cisplatin 90 mg/m(2) plus VP16 450 mg/m(2) for 14 months; subsequently, regimen II was used: VEC (VCR, VP16 300 mg/m(2), and cyclophosphamide 3 g/m(2)) for 6 months. Radiotherapy was planned for residual tumor after the completion of chemotherapy or for progression. RESULTS: We treated 23 boys and 18 girls who were a median 22 months old; 14 were given regimen I, 27 were given regimen II; 22 underwent complete resection, 19 had residual tumor. Ependymoma was Grade 2 in 25 patients and Grade 3 in 16; tumors were infratentorial in 37 patients and supratentorial in 4. One child had intracranial metastases; 29 had progressed locally after a median 9 months. Event-free survival was 26% at 3 and 5 years and 23% at 8 years. One child died of sepsis, and another developed a glioblastoma 72 months after RT. Progression-free survival was 27% at 3, 5, and 8 years, and overall survival was 48%, 37%, and 28% at 3, 5, and 8 years, respectively. Of the 13 survivors, 6 never received RT; their intellectual outcome did not differ significantly in those children than in those without RT. CONCLUSIONS: Our results confirm poor rates of event-free survival and overall survival for up-front chemotherapy in infant ependymoma. No better neurocognitive outcome was demonstrated in the few survivors who never received RT.

The effects of saquinavir on imatinib-resistant chronic myelogenous leukemia cell lines.

We evaluated the effect of the human immunodeficiency virus (HIV) protease inhibitor saquinavir on the imatinib-sensitive and imatinib-resistant chronic myelogenous leukemia cell lines. Saquinavir, which is also a proteasome blocker, showed dose- and time-related anti-proliferative activity, particularly on the imatinib-resistant lines and a pro-apoptotic effect. Association with imatinib caused a significant increase of activity.

Treatment with oral etoposide for childhood recurrent ependymomas.

In this study the authors retrospectively evaluated the feasibility and effectiveness of prolonged oral etoposide therapy in children with recurrent ependymoma. Twelve ependymoma patients with documented recurrent or persistent disease were treated between May 1998 and October 2003. All patients were treated monthly with oral VP-16 administered at a dose of 50 mg/m2/d for 21 days, with a 7-day interval between cycles, for a planned minimum number of six cycles. Response (complete plus partial) after two cycles occurred in 5 of the 12 patients (41.6%). Response plus stable disease occurred in 10 of the 12 (83.3%), with a median duration of response or stable disease of 7 months (range 4-30). The median survival was 7 months; the 2-year progression-free survival was 16.7%. These results emphasize that oral etoposide is an attractive option for childhood recurrent ependymomas in terms of administration, tolerability, and neuroradiologic response.

Schinzel-Giedion syndrome with sacrococcygeal teratoma.

A case of Schinzel-Giedion syndrome, a rare malformation syndrome, is described. In addition to the classic features of the syndrome, the patient had a malignant sacrococcygeal teratoma and agenesis of the corpus callosum. So far, this patient is the fifth case with a sacrococcygeal tumor and the eighth with anomalies of the corpus callosum. According to this occurrence of uncommon tumors, risk of malignancy could be a component of Schinzel-Giedion syndrome.