Germline pathogenic SMARCA4 variants in neuroblastoma.

Heterozygous germline pathogenic variants (GPVs) in SMARCA4, the gene encoding the ATP-dependent chromatin remodelling protein SMARCA4 (previously known as BRG1), predispose to several rare tumour types, including small cell carcinoma of the ovary, hypercalcaemic type, atypical teratoid and malignant rhabdoid tumour, and uterine sarcoma. The increase in germline testing of SMARCA4 in recent years has revealed putative GPVs affecting SMARCA4 in patients with other cancer types. Here we describe 11 patients with neuroblastoma (NBL), including 4 previously unreported cases, all of whom were found to harbour heterozygous germline variants in SMARCA4 Median age at diagnosis was 5 years (range 2 months-26 years); nine were male; and eight of nine cases had tumour location information in the adrenal gland. Eight of the germline variants were expected to result in loss of function of SMARCA4 (large deletion, truncating and canonical splice variants), while the remaining four were missense variants. Loss of heterozygosity of the wild-type SMARCA4 allele was found in all eight cases where somatic testing was performed, supporting the notion that SMARCA4 functions as a classic tumour suppressor. Altogether, these findings strongly suggest that NBL should be included in the spectrum of SMARCA4-associated tumours.

Renal cell carcinoma in children and adolescents: a retrospective study of a French-Italian series of 93 cases.

AIMS: Renal cell carcinomas (RCCs) represent 2-5% of kidney malignancies in children and adolescents. Appropriate diagnostic and classification are crucial for the correct management of the patients and in order to avoid inappropriate pre-operative chemotherapy, which is usually recommended if a Wilms' tumour is suspected. METHODS AND RESULTS: A French-Italian series of 93 renal cell carcinomas collected from 1990 to 2019 in patients aged less than 18 years was reclassified according to the 2016 World Health Organization (WHO) classification and the latest literature. TFE3 and TFEB fluorescence in-situ hybridisation (FISH) analyses and a panel of immunohistochemical stains were applied. The median age at diagnosis was 11 years (range = 9 months-17 years). MiT family (MiTF) translocation RCCs accounted for 52% of the tumours, followed by papillary (20%) and unclassified RCCs (13%). Other subtypes, such as SDHB-deficient and fumarate hydratase-deficient RCCs, represented 1-3% of the cases. We also described a case of ALK-rearranged RCC with a metanephric adenoma-like morphology. CONCLUSION: A precise histological diagnosis is mandatory, as targeted therapy could be applied for some RCC subtypes, i.e. MiTF-translocation and ALK-translocation RCC. Moreover, some RCC subtypes may be associated with a predisposition syndrome that will impact patients' and family's management and genetic counselling. A precise RCC subtype is also mandatory for the clinical management of the patients and inclusion in new prospective clinical trials.

Neuroblastoma With Intraspinal Extension: Health Problems in Long-Term Survivors.

AIM: To evaluate the prevalence of health problems in 5-year survivors treated for neuroblastoma (NBL) with intraspinal extension. PATIENTS AND METHODS: Retrospective, single center cohort study (using data from Childhood Cancer Registry and medical records) of patients treated for NBL with intraspinal extension (between 1980 and 2007) who survived ≥ 5 years after diagnosis. Health problems were graded according to the Common Terminology Criteria for Adverse Events (CTCAEv.3.0). RESULTS: All eligible patients (n = 19) were included (n = 7 no neurological symptoms at diagnosis), median age at diagnosis was 1.2 years (0.6-10.8 years), and median follow-up time was 15.6 years (6.3-29.5 years). Ninety-five percent of survivors had ≥1 health problem and 48% of survivors had ≥4 health problem with a mean of 3.8 per survivor. Fifty-three percent of survivors had at least one severe (grade 3) or life-threatening/disabling (grade 4) health problem. The three most prevalent health problems were kyphosis and/or scoliosis (68% of patients), motor neuropathy (32% of patients), and sensory neuropathy (26% of patients). Of the 13 patients who underwent a laminectomy, 54% (seven of 13) developed a grade 3 and 23% (three of 13) developed a grade 4 health problem. Among six patients, without laminectomy, 17% developed (one of six) a grade 3 and in 17% developed (one of six) a grade 4 health problem. CONCLUSIONS: Ninety-five percent of 5-year survivors treated for a childhood intraspinal NBL have health problems. The high prevalence of grade 3 and 4 health problems (especially in the laminectomy group) emphasizes the importance of specialized long-term multidisciplinary follow-up and identifies optimal treatment with limited morbidity and maximal efficacy.

Immune Monitoring during Therapy Reveals Activitory and Regulatory Immune Responses in High-Risk Neuroblastoma.

Despite intensive treatment, including consolidation immunotherapy (IT), prognosis of high-risk neuroblastoma (HR-NBL) is poor. Immune status of patients over the course of treatment, and thus immunological features potentially explaining therapy efficacy, are largely unknown. In this study, the dynamics of immune cell subsets and their function were explored in 25 HR-NBL patients at diagnosis, during induction chemotherapy, before high-dose chemotherapy, and during IT. The dynamics of immune cells varied largely between patients. IL-2- and GM-CSF-containing IT cycles resulted in significant expansion of effector cells (NK-cells in IL-2 cycles, neutrophils and monocytes in GM-CSF cycles). Nonetheless, the cytotoxic phenotype of NK-cells was majorly disturbed at the start of IT, and both IL-2 and GM-CSF IT cycles induced preferential expansion of suppressive regulatory T-cells. Interestingly, proliferative capacity of purified patient T-cells was impaired at diagnosis as well as during therapy. This study indicates the presence of both immune-enhancing as well as regulatory responses in HR-NBL patients during (immuno)therapy. Especially the double-edged effects observed in IL-2-containing IT cycles are interesting, as this potentially explains the absence of clinical benefit of IL-2 addition to IT cycles. This suggests that there is a need to combine anti-GD2 with more specific immune-enhancing strategies to improve IT outcome in HR-NBL.