[Multiple primary tumors in children: a clinicopathological analysis of four cases].

Objective: To investigate the clinicopathological features of children with metachronous or synchronous primary tumors and to identify related genetic tumor syndromes. Methods: The clinicopathological data of 4 children with multiple primary tumors diagnosed in the Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China from 2011 to 2023 were collected. The histological, immunophenotypic and molecular characteristics were examined using H&E staining, immunohistochemical staining, PCR, Sanger sequencing and next-generation sequencing (NGS). The patients were followed up. Results: Case 1 was an 8-year-old boy with the adrenal cortical carcinoma, and 5 years later a poorly differentiated gastric adenocarcinoma was detected. Case 2 was a 2-year-old boy, presented with a left ventricular choroid plexus carcinoma, and a hepatoblastoma was detected 8 months later. Case 3 was a 9-month-old girl, diagnosed with renal rhabdoid tumor first and intracranial atypical teratoid/rhabdoid tumor (AT/RT) 3 months later. Case 4 was a 7-year-old boy and had a sigmoid colon adenocarcinoma 3 years after the diagnosis of a glioblastoma. The morphology and immunohistochemical features of the metachronous or synchronous primary tumors in the 4 cases were similar to the corresponding symptom-presenting/first-diagnosed tumors. No characteristic germ line mutations were detected in cases 1 and 2 by relevant molecular detection, and the rhabdoid tumor predisposition syndrome was confirmed in case 3 using NGS. Case 4 was clearly related to constitutional mismatch repair deficiency as shown by the molecular testing and clinical features. Conclusions: Childhood multiple primary tumors are a rare disease with histological morphology and immunophenotype similar to the symptom-presenting tumors. They are either sporadic or associated with a genetic (tumor) syndrome. The development of both tumors can occur simultaneously (synchronously) or at different times (metachronously). Early identification of the children associated with genetic tumor syndromes can facilitate routine tumor screening and early treatment.

Immunohistochemical Approach to Mismatch Repair Deficiency in Pediatric High-Grade Glioma.

Knowledge of the molecular pathways of pediatric high-grade gliomas is increasing. Gliomas with mismatch repair deficiency do not currently comprise a distinct group, but data on this topic have been accumulating in recent publications. Immunohistochemistry can effectively determine mismatch repair status, indirectly suggesting the microsatellite instability of the tumor. This study aimed to determine the number of mismatch repair-deficient pediatric high-grade gliomas in a tertiary institution and assess the relationship between the survival and mismatch repair status of the patients. It also aimed to assess the potential for further clinical studies including immunotherapy. Of 24 patients with high-grade gliomas, 3 deceased patients were mismatch repair-deficient. Mismatch repair deficiency was significantly associated with shorter survival ( P =0.004). Immunotherapy trials need to progress, and patients with mismatch repair-deficient pediatric high-grade gliomas are the most suitable candidates for such studies.

Fumarate hydratase-deficient renal cell carcinoma: an oncology care institutional experience.

Renal cell carcinoma (RCC) accounts for 2% of all cancer cases worldwide, and majority are sporadic. The latest World Health Organization (WHO) classification of renal cell tumors (fifth edition, 2022) has molecularly defined renal tumor entities, which includes fumarate hydratase (FH)-deficient RCC. FH-deficient RCC is an aggressive carcinoma caused by pathogenic alterations in FH gene, seen in 15% of patients with hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) syndrome. These tumors occur more frequently at a younger age and present at an advanced stage, carrying a dismal prognosis. We report a series of 10 cases of FH-deficient RCC. The mean age was 49.8 years, and all cases presented in advanced stages (III and IV). Morphologically, the cases had varied architectural patterns with characteristic eosinophilic macronucleoli and perinucleolar halo. On immunohistochemistry (IHC), all showed diffuse nucleo-cytoplasmic expression of S-(2-succino)-cysteine (2-SC), with loss of FH in seven cases. FH-deficient RCCs are aggressive neoplasms and can be diagnosed using specific IHC markers (FH and 2-SC). These patients should undergo germline testing for FH gene mutation, genetic counseling, and surveillance of family members.

NLRC5 promotes endometrial carcinoma progression by regulating NF-κB pathway-mediated mismatch repair gene deficiency.

The innate immune molecule NLR family CARD domain-containing 5 (NLRC5) plays a significant role in endometrial carcinoma (EC) immunosurveillance. However, NLRC5 also plays a protumor role in EC cells. Mismatch repair gene deficiency (dMMR) can enable tumors to grow faster and also can exhibit high sensitivity to immune checkpoint inhibitors. In this study, we attempted to determine whether NLRC5-mediated protumor role in EC is via the regulation of dMMR. Our findings revealed that NLRC5 promoted the proliferation, migration, and invasion abilities of EC cells and induced the dMMR status of EC in vivo and in vitro. Furthermore, the mechanism underlying NLRC5 regulated dMMR was also verified. We first found NLRC5 could suppress nuclear factor-kappaB (NF-κB) pathway in EC cells. Then we validated that the positive effect of NLRC5 in dMMR was restricted when NF-κB was activated by lipopolysaccharides in NLRC5-overexpression EC cell lines. In conclusion, our present study confirmed the novel NLRC5/NF-κB/MMR regulatory mechanism of the protumor effect of NLRC5 on EC cells, thereby suggesting that the NLRC5-mediated protumor in EC was depend on the function of MMR.

Death receptors 4/5 mediate tumour sensitivity to natural killer cell-mediated cytotoxicity in mismatch repair deficient colorectal cancer.

BACKGROUND: Identifying the target of natural killer (NK) cells in colorectal cancer (CRC) is critical for optimising the clinical use of NK cell-mediated immunotherapy. Mismatch repair deficiency (dMMR) is associated with high immune cell infiltration and MHC Class I defects. Whether dMMR CRC responses to NK cell therapy remains unclear. METHODS: MLH1, DR4, and DR5 knockout cell lines were established using CRISPR-Cas9 system. NK92-MI or NK cell isolated from BABL/C mice were used as effector cells against tumour cells. Inflammatory cytokines secretion by CRC cells was assessed via cytokine analysis. NK-cell-deficient/proficient animal models were used to validate the NK cell sensitivity. RESULTS: We observed that dMMR CRC cells were more sensitive to NK cell-mediated cytotoxicity than were mismatch-repair-proficient (pMMR) CRC cells. In dMMR CRC, Death receptor (DR)4/5 was upregulated and mediated sensitivity to NK cell-mediated cytotoxicity. DR4/5-mediated secretion of interleukin -12 sustained NK cell viability in dMMR CRC. NK cell depletion induced dMMR CRC tumour growth, and NK cell transfer inhibited lung metastasis of dMMR CRC with DR4/5 expression in vivo. TP53 upregulated DR4/DR5 expression in dMMR CRC. CONCLUSIONS: dMMR associated with increased sensitivity to NK cell-mediated cytotoxicity in CRC. DR4/DR5 sensitise dMMR CRC to NK cell-mediated cytotoxicity.

Outcomes of patients with Juvenile Polyposis-Hereditary Haemorrhagic Telangiectasia caused by pathogenic SMAD4 variants in a pan-Scotland cohort.

Constitutional loss of SMAD4 function results in Juvenile Polyposis-Hereditary Haemorrhagic Telangiectasia Overlap Syndrome (JP-HHT). A retrospective multi-centre case-note review identified 28 patients with a pathogenic SMAD4 variant from 13 families across all Scottish Clinical Genetics Centres. This provided a complete clinical picture of the Scottish JP-HHT cohort. Colonic polyps were identified in 87% (23/28) and gastric polyps in 67% (12/18) of screened patients. Complication rates were high: 43% (10/23) of patients with polyps required a colectomy and 42% (5/12) required a gastrectomy. Colorectal cancer occurred in 25% (7/28) of patients, at a median age of 33 years. Pulmonary arteriovenous malformations were identified in 42% (8/19) of screened patients. 88% (23/26) and 81% (17/21) of patients exhibited JP and HHT features respectively, with 70% (14/20) demonstrating features of both conditions. We have shown that individuals with a pathogenic SMAD4 variant are all at high risk of both gastrointestinal neoplasia and HHT-related vascular complications, requiring a comprehensive screening programme.

Segregation, immunohistochemical, molecular and functional analyses classify a novel missense variant in fumarate hydratase (FH) as pathogenic.

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant cancer predisposition syndrome characterized by cutaneous leiomyomas, uterine leiomyomas, and aggressive renal cancer. Germline variants in the fumarate hydratase (FH) gene predispose to HLRCC. Identifying germline pathogenic FH variants enables lifetime renal cancer screening and genetic testing for family members. In this report, we present a FH missense variant (c.1039T>C (p.S347P)), initially classified as a variant of uncertain significance. Clinical assessment, histopathological findings, molecular genetic studies, and enzymatic activity studies support the re-classification of the FH c.1039T>C variant to "pathogenic" based on ACMG/AMP criteria. Further insights into pathological recognition of FH-deficient renal cancer are discussed and should be recognized. This study has shown how (a) detailed multi-disciplinary analyses of a single variant can reclassify rare missense variants in FH and (b) careful pathological review of renal cancers is obligatory when HLRCC is suspected.

Familial syndromes associated with testicular and paratesticular neoplasms: a comprehensive review.

A syndromic association between a subset of testicular/paratesticular neoplasms is well established. Such examples include Carney complex and large cell calcifying Sertoli cell tumor, Peutz-Jeghers syndrome and intratubular large cell hyalinizing Sertoli cell neoplasia, and VHL syndrome and clear cell papillary cystadenoma of the epididymis.However, recent studies proposed potential novel links between some testicular and paratesticular neoplasms with certain tumor syndromes. While more studies are still needed to solidify these associations, recent research suggests that a subset of Leydig cell tumors may arise in patients with hereditary leiomyomatosis and renal cell carcinoma syndrome or that some seminomas may occur in Lynch syndrome patients. Additionally, an association between testicular sex cord stromal tumors and paratesticular sarcomas with Familial adenomatous polyposis syndrome and DICER1 syndrome, respectively, has been proposed as well. This review provides a comprehensive overview of the intricate relationship between familial syndromes and associated testicular and paratesticular tumors, shedding light on their clinicopathological and molecular characteristics.

Phenotypic characterisation of SMAD4 variant carriers.

BACKGROUND: Both hereditary haemorrhagic telangiectasia (HHT) and juvenile polyposis syndrome (JPS) are known to be caused by SMAD4 pathogenic variants, with overlapping symptoms for both disorders in some patients. Additional connective tissue disorders have also been reported. Here, we describe carriers of SMAD4 variants followed in an HHT reference centre to further delineate the phenotype. METHODS: Observational study based on data collected from the Clinical Investigation for the Rendu-Osler Cohort database. RESULTS: Thirty-three participants from 15 families, out of 1114 patients with HHT, had an SMAD4 variant (3%).Regarding HHT, 26 out of 33 participants (88%) had a definite clinical diagnosis based on Curaçao criteria. Complication frequencies were as follows: epistaxis (n=27/33, 82%), cutaneous telangiectases (n=19/33, 58%), pulmonary arteriovenous malformations (n=17/32, 53%), hepatic arteriovenous malformations (AVMs) (n=7/18, 39%), digestive angiodysplasia (n=13/22, 59%). No cerebral AVMs were diagnosed.Regarding juvenile polyposis, 25 out of 31 participants (81%) met the criteria defined by Jass et al for juvenile polyposis syndrome. Seven patients (21%) had a prophylactic gastrectomy due to an extensive gastric polyposis incompatible with endoscopic follow-up, and four patients (13%) developed a digestive cancer.Regarding connective tissue disorders, 20 (61%) had at least one symptom, and 4 (15%) participants who underwent echocardiography had an aortic dilation. CONCLUSION: We describe a large cohort of SMAD4 variant carriers in the context of HHT. Digestive complications are frequent, early and diffuse, justifying endoscopy every 2 years. The HHT phenotype, associating pulmonary and hepatic AVMs, warrants systematic screening. Connective tissue disorders broaden the phenotype associated with SMAD4 gene variants and justify systematic cardiac ultrasound and skeletal complications screening.

Multiple cutaneous and uterine leiomyomatosis: Reed's syndrome.

Reed's syndrome (RS) is a rare autosomal-dominant disorder characterised by multiple cutaneous and uterine leiomyomas, with a strong tendency for renal cell carcinoma (RCC) development. A woman in her 50s, who had previously undergone total abdominal hysterectomy due to multiple uterine leiomyomas, presented with painful nodules on her trunk and right arm for the past 6 years. These nodules were confirmed as leiomyomas through histopathology. Diagnosis of RS was established through clinicopathological correlation and positive family history, particularly her mother's. Early-onset uterine leiomyomas in patients with a similar family history should raise suspicion for RS, necessitating vigilant long-term follow-up. RCC detection requires mandatory renal imaging. Screening family members and providing genetic counselling are crucial.

The c.386A>C p.(Asn129Thr) variant in SMAD4 is likely to be pathogenic, causing Juvenile Polyposis Syndrome. A case report of a mosaic variant.

BACKGROUND: Juvenile Polyposis Syndrome (JPS) is a rare autosomal dominant hereditary disorder characterized by the development of multiple hamartomatous gastrointestinal polyps. Here, we present a case of JPS with a mosaic variant in SMAD4. METHODS: Exome sequencing TRIO analysis, using germline DNA from the biological mother and father along with the index case (IC). RESULTS: A 46-year-old male with no family history of cancer presented with chronic iron deficiency anemia and was diagnosed with massive gastric polyposis (≥100 polyps). At the age of 59, he underwent a total gastrectomy, revealing numerous polyps occupying the entire gastric mucosa, including a 5 cm gastric hyperplastic polyp with high-grade dysplasia and focal adenocarcinoma. TRIO analysis identified the c.386A>C p.(Asn129Thr) variant in the SMAD4 gene at an allele frequency (AF) of 22%, suggesting its mosaic origin. Subsequently, the variant was found in heterozygosity in the IC's son, who exhibited two subcentimeter polyps in the colon and seven inflammatory gastric polyps with gastric inflammatory areas and hyperplasia, suggesting that the c.386A>C p.(Asn129Thr) variant in SMAD4 segregated with the phenotype. CONCLUSION: Our study provides evidence supporting the classification of the c.386A>C p.(Asn129Thr) variant in SMAD4 as a likely pathogenic variant. This finding contributes to improved accuracy in the diagnosis and genetic counseling of JPS.

Rerouting the GPS Directing Immunotherapy in Endometrial Cancer.

Mismatch repair (MMR) status alone is insufficient to guide the use of PD-(L)1 monotherapy in patients with endometrial cancer. Additional biomarkers, including tumor mutational burden and combined positive score, may help to identify patients with MMR-proficient tumors with a high probability of benefit from PD-(L)1 monotherapy, and those with MMR-deficient tumors who might require combination strategies. See related article by Oaknin et al., p. 4564.

A Case of Juvenile Polyposis Syndrome in a 13-year-old: A Case Report.

Juvenile polyposis syndrome is an autosomal dominant syndrome characterised by hamartomatous polyps in the gastrointestinal tract and has a high risk for colon carcinoma. This case explores the presentation of multiple polyps throughout the gastrointestinal tract, located in the stomach, proximal duodenum, colon, rectum and up to the anal canal. The locations and number of these polyps themselves were not typical and the histopathological studies suggested the condition to be an inflammatory fibroid polyp, which is a rare, benign and solitary neoplasm. Prompt and accurate diagnostic modality remains the keystone in the identification and management of such condition which was a limitation in this case as the patient was lost to follow up before a definitive diagnosis was made. Keywords: case reports; children; juvenile polyposis syndrome.

Brooke-Spiegler syndrome: radiotherapy as the last resort?

PURPOSE: To describe the case of successful radiotherapeutic treatment of a woman suffering from Brooke-Spiegler syndrome who had multiple disfiguring cylindromas on the entire scalp and further tumors on the trunk. METHODS: After decades of treatment with conventional therapies including surgery and topically applied salicylic acid, the 73-year-old woman agreed to undergo radiotherapeutic treatment. She received 60 Gy to the scalp and 36 Gy to painful nodules in the lumbar spine region. RESULTS: Over a follow-up period of 14 and 11 years, respectively, the scalp nodules almost completely regressed, while the lumbar nodules became painless and considerably smaller. Apart from alopecia, no late adverse effects of treatment remain. CONCLUSION: This case should remind us of the potential role that radiotherapy could play in treating Brooke-Spiegler syndrome. The required dose for treatment of such extensive disease is still a matter of debate due to the scarcity of radiotherapeutic experience. This case demonstrates that for scalp tumors, 30â€¯× 2 Gy can result in long-term tumor control, while other dose prescriptions may be adequate for tumors in other locations.

Endolymphatic sac tumour - a rare complication associated with von Hippel-Lindau disease.

We report the case of a 42-year - old female with familiar form von Hippel-Lindau disease (VHL) and recurrent endolymphatic sac tumour (ELST), which was presented like non-homogenous, solid and cystic expansion of the left petrous temporal bone. Histologically, there was found lamellae of bone with adjacent ligament and with papillary projections with fibrovascular core. The papillae were lined by a single layer of cuboidal epithelium with hyperchromatic and lightly pleomorphic nuclei. Sporadically, small cystic formations with eosinophilic, PAS positive secretion were noted. Imunohistochemically, the cuboidal cells showed diffuse positivity for vimentin, epithelial membrane antigen (EMA), cytokeratin AE1/AE3 and S100 protein (weakly). Other markers examined, including TTF1, PAX8 and CD10, were negative. Endolymphatic sac tumour is rare low-grade malignant epithelial tumour arising from the endolymphatic sac in the temporal bone, which occurs in 1 out of 30 000 births, with just fewer than 300 cases reported in the literature. About one third of cases are associated with von Hippel- Lindau disease, an autosomal dominant familial cancer syndrome.