The evidence-based role of catecholaminergic PET tracers in Neuroblastoma. A systematic review and a head-to-head comparison with mIBG scintigraphy.

BACKGROUND: Molecular imaging is pivotal in staging and response assessment of children with neuroblastoma (NB). [123I]-metaiodobenzylguanidine (mIBG) is the standard imaging method; however, it is characterised by low spatial resolution, time-consuming acquisition procedures and difficult interpretation. Many PET catecholaminergic radiotracers have been proposed as a replacement for [123I]-mIBG, however they have not yet made it into clinical practice. We aimed to review the available literature comparing head-to-head [123I]-mIBG with the most common PET catecholaminergic radiopharmaceuticals. METHODS: We searched the PubMed database for studies performing a head-to-head comparison between [123I]-mIBG and PET radiopharmaceuticals including meta-hydroxyephedrine ([11C]C-HED), 18F-18F-3,4-dihydroxyphenylalanine ([18F]DOPA) [124I]mIBG and Meta-[18F]fluorobenzylguanidine ([18F]mFBG). Review articles, preclinical studies, small case series (< 5 subjects), case reports, and articles not in English were excluded. From each study, the following characteristics were extracted: bibliographic information, technical parameters, and the sensitivity of the procedure according to a patient-based analysis (PBA) and a lesion-based analysis (LBA). RESULTS: Ten studies were selected: two regarding [11C]C-HED, four [18F]DOPA, one [124I]mIBG, and three [18F]mFBG. These studies included 181 patients (range 5-46). For the PBA, the superiority of the PET method was reported in two out of ten studies (both using [18F]DOPA). For LBA, PET detected significantly more lesions than scintigraphy in seven out of ten studies. CONCLUSIONS: PET/CT using catecholaminergic tracers shows superior diagnostic performance than mIBG scintigraphy. However, it is still unknown if such superiority can influence clinical decision-making. Nonetheless, the PET examination appears promising for clinical practice as it offers faster image acquisition, less need for sedation, and a single-day examination.

Verrucous epidermal nevus as a manifestation of a type 2 mosaic PTEN mutation in Cowden syndrome.

Linear Cowden nevus, also known as linear PTEN nevus, is a type of epidermal nevus, first described in 2007, which is seen in patients with PTEN hamartoma tumor syndrome. It is considered to be a type 2 form of segmental mosaicism, and we suggest that it has certain clinical features that distinguish it from epidermal nevi seen in similar conditions, such as Proteus syndrome. We present a case of linear Cowden nevus in a 4-year-old boy and review the literature.

Neurofibromatosis type 1 families with first-degree relatives harbouring distinct NF1 pathogenic variants. Genetic counselling and familial diagnosis: what should be offered?

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder caused by pathogenic variants in NF1 Recently, NF1 testing has been included as a clinical criterion for NF1 diagnosis. Additionally, preconception genetic counselling in patients with NF1 focuses on a 50% risk of transmitting the familial variant as the risk of having a sporadic NF1 is considered the same as the general population. METHODS: 829 individuals, 583 NF1 sporadic cases and 246 patients with NF1 with documented family history, underwent genetic testing for NF1. Genotyping and segregation analysis of NF1 familial variants was determined by microsatellite analysis and NF1 sequencing. RESULTS: The mutational analysis of NF1 in 154 families with two or more affected cases studied showed the co-occurrence of two different NF1 germline pathogenic variants in four families. The estimated mutation rate in those families was 3.89×10-3, 20 times higher than the NF1 mutation rate (~2×10-4) (p=0.0008). Furthermore, the co-occurrence of two different NF1 germline pathogenic variants in these families was 1:39, 60 times the frequency of sporadic NF1 (1:2500) (p=0.003). In all cases, the de novo NF1 pathogenic variant was present in a descendant of an affected male. In two cases, variants were detected in the inherited paternal wild-type allele. CONCLUSIONS: Our results, together with previous cases reported, suggest that the offspring of male patients with NF1 could have an increased risk of experiencing de novo NF1 pathogenic variants. This observation, if confirmed in additional cohorts, could have relevant implications for NF1 genetic counselling, family planning and NF1 genetic testing.

Revisiting the UK Genetic Severity Score for NF2: a proposal for the addition of a functional genetic component.

BACKGROUND: Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder characterised by the development of multiple schwannomas, especially on vestibular nerves, and meningiomas. The UK NF2 Genetic Severity Score (GSS) is useful to predict the progression of the disease from germline NF2 pathogenic variants, which allows the clinical follow-up and the genetic counselling offered to affected families to be optimised. METHODS: 52 Spanish patients were classified using the GSS, and patients' clinical severity was measured and compared between GSS groups. The GSS was reviewed with the addition of phenotype quantification, genetic variant classification and functional assays of Merlin and its downstream pathways. Principal component analysis and regression models were used to evaluate the differences between severity and the effect of NF2 germline variants. RESULTS: The GSS was validated in the Spanish NF2 cohort. However, for 25% of mosaic patients and patients harbouring variants associated with mild and moderate phenotypes, it did not perform as well for predicting clinical outcomes as it did for pathogenic variants associated with severe phenotypes. We studied the possibility of modifying the mutation classification in the GSS by adding the impact of pathogenic variants on the function of Merlin in 27 cases. This revision helped to reduce variability within NF2 mutation classes and moderately enhanced the correlation between patient phenotype and the different prognosis parameters analysed (R2=0.38 vs R2=0.32, p>0001). CONCLUSIONS: We validated the UK NF2 GSS in a Spanish NF2 cohort, despite the significant phenotypic variability identified within it. The revision of the GSS, named Functional Genetic Severity Score, could add value for the classification of mosaic patients and patients showing mild and moderate phenotypes once it has been validated in other cohorts.

Manifestations, clinical course and prognostic markers in cutaneous polyarteritis nodosa.

BACKGROUND AND OBJECTIVES: Cutaneous polyarteritis nodosa (CPAN) is a comparatively rare form of vasculitis that affects small arteries and arterioles in the panniculus and dermo-subcutaneous junction. Limited information is available regarding its course in the European population. The aim of this study is to characterize the manifestations and prognostic markers of recurrence in CPAN. PATIENTS AND METHODS: We report a retrospective study of patients with clinical and histopathologic evidence of CPAN, which was treated at two tertiary referral centers in Spain between 1989 and 2019. RESULTS: 31 patients were included. The most frequent manifestation was subcutaneous nodules (90.3 %); ulcers were frequent at diagnosis (35.5 %). Two thirds of the patients had at least one extracutaneous manifestation. Seventeen patients (54.8 %) experienced relapse. The strongest predictor of recurrence was ulceration in the initial episode (OR 18.6; 95 % CI 2.73-38; p < 0.01). The pre-treatment results of laboratory parameters associated with inflammation (such as C-reactive protein and neutrophil-to-lymphocyte ratio) were significantly higher in the relapsing group. There were no disease-related deaths and none of the patients developed systemic PAN. CONCLUSIONS: Although CPAN is a vasculitis limited to the skin, symptoms may involve adjacent skeletal muscle or peripheral nerves. While the condition is not life-threatening, the presence of ulceration and elevation of certain laboratory parameters predicts a worse prognosis.

One-step nucleic acid amplification for intraoperative analysis of sentinel lymph node in papillary thyroid carcinoma.

Objective Lymphadenectomy in papillary thyroid carcinoma (PTC) is controversial. It is indicated whenever metastases have been proven before or during surgery and as a prophylactic treatment in high-risk patients. However, 30-50% of cN0 patients become pN1 postoperatively. In PTC, selective-sentinel-lymph-node-biopsy (SLNB) with conventional intraoperative analysis is 8% false negative. One-step nucleic acid amplification (OSNA) is a molecular technique which allows real-time detection of mRNA encoding for cytokeratin 19. OSNA has been introduced in intraoperative analysis of several tumors to reduce false-negative rates and distinguish micrometastasis from macrometastasis. Our objective was to evaluate the impact of the introduction of OSNA in the intraoperative evaluation of the sentinel node (SN) in PTC. Design We analyzed a series of 35 patients subjected to SLNB. Methods All the dissected nodes, SN and non-SN, were evaluated with OSNA and cytology. Results We obtained a total of 110 SN. SLNB proved positive in 14 patients (40%) with cytology and in 23 (65.7%) with OSNA (P < 0.001). In the 29 patients with subsequent lymphadenectomy we obtained 360 lymph nodes ((52 positive in cytology (14.4%) and 107 in OSNA (29.7%)). Lymphadenectomy proved positive in 16 patients according to cytology (55%) and in 24 according to OSNA (83%) (P = 0002). The majority of patients with micrometastasis in SN showed only micrometastasis in lymphadenectomy. Conclusions The present study shows selective-sentinel-lymph-node-biopsy with one-step nucleic acid amplification technique to be feasible in papillary thyroid carcinoma. The quantitative nature of one-step nucleic acid amplification paves the way toward a more personalized surgical approach, limiting lymphadenectomy to patients with intraoperative evidence of macrometastasis in the sentinel node.

Subcutaneous panniculitis-like T-cell lymphoma: Clinical features, therapeutic approach, and outcome in a case series of 16 patients.

BACKGROUND: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare primary cutaneous lymphoma of mature cytotoxic T cells. Initially, patients with SPTCL were treated with doxorubicin-based polychemotherapy. OBJECTIVE: To analyze clinical, biologic, immunophenotypical, molecular, imaging, treatment, and outcome data reflecting the current state of knowledge. METHODS: A retrospective multicenter study of 16 patients with SPTCL that was diagnosed between 1996 and 2016. RESULTS: The female-to-male ratio was 1.7. The median age at diagnosis was 46.5 years. Patients presented with multiple nodular or plaque-like lesions preferentially affecting the legs and/or trunk. Histopathology typically showed a lobular panniculitis with individual adipocytes surrounded by atypical lymphocytes, usually with a CD3+, CD4-, CD8+, CD56-, TIA1 cytotoxic granule associated RNA binding protein 1-positive phenotype and high proliferation rate. SPTCL was associated with autoimmune diseases in 25% of patients, and with the development of hemophagocytic syndrome in 18% of patients. Oral steroids alone or in combination with low-dose methotrexate or cyclosporine A were the most common initial treatment, achieving a complete response in 85% of the treated patients. The median follow-up time was 14 months. The 5-year disease-specific survival rate was 85.7%. LIMITATIONS: This was a retrospective study. CONCLUSIONS: SPTCL has an excellent prognosis. Immunosuppressive agents can be considered for first-line treatment.

Early Genetic Diagnosis of Neurofibromatosis Type 2 From Skin Plaque Plexiform Schwannomas in Childhood.

Importance: Neurofibromatosis type 2 (NF2) is a devastating genetic condition characterized by the development of multiple tumors of the nervous system. An early diagnosis of individuals with NF2 would facilitate treatment and reduction of disease impact because most severe effects of the disease do not usually develop before adolescence. Little attention has traditionally been paid to dermatological signs in NF2. However, skin plaques are commonly seen in patients with NF2, normally appearing either at birth or early childhood, providing an opportunity for early NF2 detection and testing. Objective: To determine the clinical utility of skin plaque identification and characterization in children for reaching an early diagnosis of patients with NF2 and to evaluate their molecular pathogenesis and their use in the genetic diagnostics of NF2. Design, Setting, and Participants: Diagnostic test study by the histological and genetic characterization of skin plaques from patients with NF2. Patients were 7 individuals with NF2 or clinical suspicion of NF2 treated at the Spanish Reference Center on Phakomatoses. Main Outcomes and Measures: Histological evaluation of all skin plaques was performed. Fresh skin plaques were cultured to obtain Schwann cells and the NF2 gene was genetically analyzed. For all 7 patients, NF2 clinical history was reviewed. Results: In all 7 patients (4 male and 3 female), all skin plaques analyzed were histologically characterized as plexiform schwannomas. Genetic analysis of primary Schwann cell cultures derived from them allowed the identification of a constitutional and a somatic NF2 mutation. Genetic testing allowed the early diagnosis of NF2 in a child only exhibiting the presence of skin plaques. Most of the patients with NF2 analyzed had an early presentation of skin plaques and a severe NF2 phenotype. Conclusions and Relevance: This work emphasizes the clinical utility of a careful dermatological inspection and the correct identification of skin plaques in children for an early diagnosis of NF2. We show for the first time that Schwann cells derived from skin plaque plexiform schwannomas bear the double inactivation of the NF2 gene and thus constitute an excellent source of tissue for genetic testing, especially in the context of mosaicism.

Segmental neurofibromatosis type 2: discriminating two hit from four hit in a patient presenting multiple schwannomas confined to one limb.

BACKGROUND: A clinical overlap exists between mosaic Neurofibromatosis Type 2 and sporadic Schwannomatosis conditions. In these cases a molecular analysis of tumors is recommended for a proper genetic diagnostics. This analysis is challenged by the fact that schwannomas in both conditions bear a somatic double inactivation of the NF2 gene. However, SMARCB1-associated schwannomas follow a four-hit, three-step model, in which both alleles of SMARCB1 and NF2 genes are inactivated in the tumor, with one of the steps being always the loss of a big part of chromosome 22 involving both loci. CASE PRESENTATION: Here we report a 36-year-old woman who only presented multiple subcutaneous schwannomas on her right leg. To help discriminate between both possible diagnoses, an exhaustive molecular genetic and genomic analysis was performed on two schwannomas of the patient, consisting in cDNA and DNA sequencing, MLPA, microsatellite multiplex PCR and SNP-array analyses. The loss of a big part of chromosome 22 (22q12.1q13.33) was identified in both tumors. However, this loss involved the NF2 but not the SMARCB1 locus. SNP-array analysis revealed the presence of the same deletion breakpoint in both schwannomas, indicating that this alteration was actually the first NF2 inactivating hit. In addition, a distinct NF2 point mutation in each tumor was identified, representing independent second hits. In accordance with these results, no deletions or point mutations in the SMARCB1 gene were identified. None of the mutations were present in the blood. Two of the patient's children inherited chromosome 22 deleted in schwannomas of the mother, but in its wild type form. CONCLUSIONS: These results conclusively confirm the segmental mosaic NF2 nature of the clinical phenotype presented.

SPECT/CT sentinel lymph node identification in papillary thyroid cancer: lymphatic staging and surgical management improvement.

PURPOSE: Lymphadenectomy in papillary thyroid carcinoma (PTC) continues to be controversial. A better staging method is needed to provide adequate individual surgical treatment. SPECT/CT lymphoscintigraphy and sentinel lymph node (SLN) biopsy may improve lymphatic staging and surgical treatment. Our main objectives were to describe the lymphatic drainage of PTC using lymphoscintigraphy, to evaluate the lymphatic spread (comparing SLN and lymphadenectomy results) and to analyse the impact of SLN identification in surgery. METHODS: We prospectively studied 24 consecutive patients with PTC (19 women; mean age 52.7 years, range 22-81 years). The day before surgery, lymphoscintigraphy with ultrasound-guided intratumoral injection ((99m)Tc-nanocolloid, 148 MBq) was performed, obtaining planar and SPECT/CT images. All patients underwent total thyroidectomy, SLN biopsy (hand-held gamma probe) with perioperative analysis, central compartment node dissection, or laterocervical lymphadenectomy if perioperative stage N1b or positive SLNs in this lymphatic basin. RESULTS: Lymphoscintigraphy revealed at least one SLN in 19 of 24 patients (79 %) on planar and SPECT/CT images, and in 23 of 24 patients (96 %) during surgery using a hand-held gamma probe. Lymph node metastases were detected with classical perioperative techniques (ultrasound guidance and surgical inspection) in 3 of 24 patients, by perioperative SLN analysis in 10 of 23, and by definitive histology in 13 of 24. The false-negative (FN) ratio for SLN was 7.7 % (one patient with bulky lymph nodes). The FN ratio for perioperative frozen sections was 15.4 % (two patients, one with micrometastases, the other with bilateral SLN). Lymphatic drainage was only to the central compartment in 6 of 24 patients (3 of the 6 with positive SLNs for metastases), only to the laterocervical basin in 5 of 24 patients (all unilateral, 2 of 5 positive SLNs) and to the central and laterocervical compartments in 12 of 24 patients (6 of 12 and 3 of 12 positive SLNs, respectively). CONCLUSION: Lymphoscintigraphy reveals the lymph node drainage in a high proportion of patients. It detects laterocervical drainage in a significant percentage of patients, allowing the detection of occult lymph node metastases and improving the surgical management in PTC.

Childhood granulomatous periorificial dermatitis with a good response to oral metronidazole.

Childhood granulomatous periorificial dermatitis (CGPD) is a condition included in the spectrum of rosacea and perioral dermatitis that affects prepubescent children. It is characterized by papular eruptions located around the mouth, nose, and eyes that histopathologically show a granulomatous pattern. We report a 9-year-old girl with CGPD who required treatment with an oral antibiotic. Oral metronidazole was administered because of its known efficacy in adult rosacea and its safety in children. The patient responded well to this therapy, showing resolution of the lesions.

In vitro antisense therapeutics for a deep intronic mutation causing Neurofibromatosis type 2.

Neurofibromatosis type 2 (NF2) is an autosomal-dominant disorder affecting about 1:33 000 newborns, mainly characterized by the development of tumors of the nervous system and ocular abnormalities. Around 85% of germline NF2 mutations are point mutations. Among them, ∼25% affect splicing and are associated with a variable disease severity. In the context of our NF2 Multidisciplinary Clinics, we have identified a patient fulfilling clinical criteria for the disease and exhibiting a severe phenotype. The patient carries a deep intronic mutation (g. 74409T>A, NG_009057.1) that produces the insertion of a cryptic exon of 167pb in the mature mRNA between exons 13 and 14, resulting in a truncated merlin protein (p.Pro482Profs*39). A mutation-specific antisense phosphorodiamidate morpholino oligomer was designed and used in vitro to effectively restore normal NF2 splicing in patient-derived primary fibroblasts. In addition, merlin protein levels were greatly recovered after morpholino treatment, decreasing patient's fibroblasts in vitro proliferation capacity and restoring cytoeskeleton organization. To our knowledge, this is the first NF2 case caused by a deep intronic mutation in which an in vitro antisense therapeutic approximation has been tested. These results open the possibility of using this approach in vivo for this type of mutation causing NF2.

Perniosis: clinical and histopathological analysis.

Perniosis are inflammatory cutaneous lesions, located on acral skin, which present in association with cold exposure. They can appear as an idiopathic dermatosis or with an underlying autoimmune disease. The use of cutaneous biopsy to distinguish between both types is controversial. We analyze the histological findings in 9 cases of idiopathic perniosis (IP) and compare them with those obtained from 11 cases of perniosis associated with an autoimmune disease (autoimmune perniosis). The most frequent histopathological features observed in cases of IP were a lymphocytic infiltrate with perivascular (8 cases, 89%) and perieccrine distribution (6 cases, 66%), dermal edema (5 cases, 55%), and necrotic keratinocytes (5 cases, 55%), whereas those found in perniosis associated with an autoimmune disease were lymphocytic infiltrate with perivascular distribution (11 cases, 100%) but without perieccrine distribution (3 cases, 27%), vacuolation of the basal layer (7 cases, 63%), and necrotic keratinocytes (5 cases, 45%). The only significant difference between both groups was the perieccrine distribution of the lymphocytic infiltrate in cases of IP, which, as mentioned in previous studies, could be considered a histopathological clue to differentiate both types of perniosis.

[Differentiated thyroid carcinoma in children: study of 80 cases]. / Carcinoma diferenciado de tiroides en niños: estudio de 80 casos.

BACKGROUND AND OBJECTIVE: The objective was to analyze the clinical profile of Differentiated Thyroid Carcinoma in children (DTC) and the predisposing factors to suffering the disease. MATERIAL AND METHOD: Eighty children with DTC were studied retrospectively. They all underwent total/near total thyroidectomy and 75 cases underwent ablative iodine therapy. Patients were controlled periodically with clinical, laboratory and imaging tests follow-up. RESULTS: Twenty eight patients were male and 52 female (mean age: 13.43+/-3.6 y). The 87.5% of patients had an increased cervical perimeter as the first clinical symptom, 65% of them corresponding to a thyroid nodule with a predominance of females. The papillary histological pattern was more frequent than the follicular pattern, and it was associated with the presence of lymph involvement and metastasis. About 56.4% of patients showed advanced disease at the time of diagnosis. 9 patients had previous irradiation. Surgical complications appeared in 32.5% of patients. At the end of follow-up (mean: 10.79+/-5.69 y) 9 patients had persistent disease with a significant relation with stage 4. CONCLUSIONS: DTC presents a higher incidence in females than in males. Cervical node is the most frequent form of initial presentation. The papillary type is more prevalent than the follicular type, and it is frequently associated with lymph node involvement and metastatic spread.