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Pediatric Blood & Cancer Nov 2023Pleuropulmonary blastoma (PPB) is the most common primary lung neoplasm of infancy and early childhood. Given the rarity of PPB, the role of positron emission tomography...
Assessing the role of positron emission tomography and bone scintigraphy in imaging of pleuropulmonary blastoma (PPB): A report from the International PPB/DICER1 Registry.
BACKGROUND
Pleuropulmonary blastoma (PPB) is the most common primary lung neoplasm of infancy and early childhood. Given the rarity of PPB, the role of positron emission tomography (PET) and bone scintigraphy (bone scans) in diagnostic evaluation and surveillance has not been documented to date. Available PET and bone scan data are presented in this study.
PROCEDURES
Patients with PPB enrolled in the International PPB/DICER1 Registry and available PET imaging and/or bone scan reports were retrospectively abstracted.
RESULTS
On retrospective analysis, 133 patients with type II and III (advanced) PPB were identified with available report(s) (PET scan only = 34, bone scan only = 83, and both bone scan and PET = 16). All advanced primary PPB (n = 11) and recurrent (n = 8) tumors prior to treatment presented with F-fluorodeoxyglucose (FDG)-avid lesions, with median maximum standardized uptake values of 7.4 and 6.7, respectively. False positive FDG uptake in the thorax was noted during surveillance (specificity: 59%). Bone metastases were FDG-avid prior to treatment. Central nervous system metastases were not discernable on PET imaging. Sensitivity and specificity of bone scans for metastatic bone disease were 89% and 92%, respectively. Bone scans had a negative predictive value of 99%, although positive predictive value was 53%. Four patients with distant bone metastases had concordant true positive bone scan and PET.
CONCLUSION
Primary, recurrent, and/or extracranial metastatic PPB presents with an FDG-avid lesion on PET imaging. Additional prospective studies are needed to fully assess the utility of nuclear medicine imaging in surveillance for patients with advanced PPB.
Topics: Humans; Child, Preschool; Retrospective Studies; Fluorodeoxyglucose F18; Positron-Emission Tomography; Radionuclide Imaging; Sensitivity and Specificity; Bone Neoplasms; Registries; Radiopharmaceuticals; Ribonuclease III; DEAD-box RNA Helicases
PubMed: 37592371
DOI: 10.1002/pbc.30628 -
Radiology Case Reports Oct 2023Congenital pulmonary airway malformation (CPAM) is a rare congenital dysplastic malformation characterized by failure of bronchial development and localized glandular...
Congenital pulmonary airway malformation (CPAM) is a rare congenital dysplastic malformation characterized by failure of bronchial development and localized glandular overgrowth. Previously known as Congenital Cystic Adenoid Malformation (CCAM), CPAM is classified into 5 types, from type 0 to type IV, depending upon the origin of pulmonary areas of the lung, cyst size, and cyst appearance. CPAM is a rare congenital anomaly typically diagnosed prenatally in ultrasound. However, few cases are diagnosed in childhood and even fewer in adulthood. CPAM can be differentiated from pulmonary sequestration based on the origin of the arterial supply; the former has its arterial supply from the pulmonary artery, whereas pulmonary sequestration has its arterial supply from the systemic circulation. Another differential diagnosis of CPAM includes congenital bronchogenic cyst, congenital lobar emphysema, pleuropulmonary blastoma, congenital cystic bronchiectasis, and congenital diaphragmatic hernia. The most common presentation is recurrent chest infection and chest pain, whereas other presentation includes pneumothorax and hemoptysis. Here, we present a case of a 6-year-old child with recurrent episodes of fever and cough diagnosed as a type II CPAM based on computed tomography findings.
PubMed: 37539443
DOI: 10.1016/j.radcr.2023.07.018 -
Pediatric Blood & Cancer Sep 2023The Children's Oncology Group (COG) Rare Tumor Committee includes the Infrequent Tumor and Retinoblastoma subcommittees, encompassing a wide range of extracranial solid...
The Children's Oncology Group (COG) Rare Tumor Committee includes the Infrequent Tumor and Retinoblastoma subcommittees, encompassing a wide range of extracranial solid tumors that do not fall within another COG disease committee. Current therapeutic trial development focuses on nasopharyngeal carcinoma, adrenocortical carcinoma, pleuropulmonary blastoma, colorectal carcinoma, melanoma, and thyroid carcinoma. Given the rarity of these tumors, novel strategies and international collaborative efforts are necessary to advance research and improve outcomes.
Topics: Child; Humans; Medical Oncology; Thyroid Neoplasms; Adrenal Cortex Neoplasms; Nasopharyngeal Neoplasms; Retinal Neoplasms
PubMed: 37458616
DOI: 10.1002/pbc.30574 -
Fetal and Pediatric Pathology Oct 2023Differential diagnosis of rhabdomyosarcoma (RMS) is challenging. Sineoculis homeobox homolog 1 (SIX1) is an oncogene involved in skeletal muscle differentiation. We...
Differential diagnosis of rhabdomyosarcoma (RMS) is challenging. Sineoculis homeobox homolog 1 (SIX1) is an oncogene involved in skeletal muscle differentiation. We compared protein expression patterns of SIX1 in RMS and its most common differential diagnoses. SIX1 immunohistochemistry in 36 RMS and in 33 tumors from seven differential diagnostic subtypes were evaluated. The fraction of SIX1 positive tumor cells was scored by three independent observers. A majority (75%) of the evaluated RMS expressed SIX1 in at least 50% of tumor cells and all except one RMS had more than 25% positive tumor cells. Neuroblastoma had less than 1% SIX1 positive tumor cells. Gonadoblastoma, malignant rhabdoid tumor, and Ewing sarcoma had 10% or less positive tumor cells. Pleuropulmonary blastoma exhibited 26-50% positive tumor cells and synovial sarcoma >50% positive cells. SIX1 immunohistochemistry is positive in most RMS, and occasionally in some tumors within the differential diagnoses of RMS.
Topics: Humans; Diagnosis, Differential; Biomarkers, Tumor; Rhabdomyosarcoma; Immunohistochemistry; Cell Differentiation; Homeodomain Proteins
PubMed: 37224459
DOI: 10.1080/15513815.2023.2214806 -
Targeting mutant dicer tumorigenesis in pleuropulmonary blastoma via inhibition of RNA polymerase I.Translational Research : the Journal of... Aug 2023DICER1 mutations predispose to increased risk for various cancers, particularly pleuropulmonary blastoma (PPB), the commonest lung malignancy of childhood. There is a...
DICER1 mutations predispose to increased risk for various cancers, particularly pleuropulmonary blastoma (PPB), the commonest lung malignancy of childhood. There is a paucity of directly actionable molecular targets as these tumors are driven by loss-of-function mutations of DICER1. Therapeutic development for PPB is further limited by a lack of biologically and physiologically-representative disease models. Given recent evidence of Dicer's role as a haploinsufficient tumor suppressor regulating RNA polymerase I (Pol I), Pol I inhibition could abrogate mutant Dicer-mediated accumulation of stalled polymerases to trigger apoptosis. Hence, we developed a novel subpleural orthotopic PPB patient-derived xenograft (PDX) model that retained both RNase IIIa and IIIb hotspot mutations and recapitulated the cardiorespiratory physiology of intra-thoracic disease, and with it evaluated the tolerability and efficacy of first-in-class Pol I inhibitor CX-5461. In PDX tumors, CX-5461 significantly reduced H3K9 di-methylation and increased nuclear p53 expression, within 24 hours' exposure. Following treatment at the maximum tolerated dosing regimen (12 doses, 30 mg/kg), tumors were smaller and less hemorrhagic than controls, with significantly decreased cellular proliferation, and increased apoptosis. As demonstrated in a novel intrathoracic tumor model of PPB, Pol I inhibition with CX-5461 could be a tolerable and clinically-feasible therapeutic strategy for mutant Dicer tumors, inducing antitumor effects by decreasing H3K9 methylation and enhancing p53-mediated apoptosis.
Topics: Humans; RNA Polymerase I; Tumor Suppressor Protein p53; Pulmonary Blastoma; Carcinogenesis; Ribonuclease III; DEAD-box RNA Helicases
PubMed: 36921796
DOI: 10.1016/j.trsl.2023.03.001 -
Familial Cancer Oct 2023Pathogenic germline DICER1 variants are associated with pleuropulmonary blastoma, multinodular goiter, embryonal rhabdomyosarcoma and other tumour types, while mosaic...
Pathogenic germline DICER1 variants are associated with pleuropulmonary blastoma, multinodular goiter, embryonal rhabdomyosarcoma and other tumour types, while mosaic missense DICER1 variants in the RNase IIIb domain are linked to cause GLOW (global developmental delay, lung cysts, overgrowth, and Wilms' tumor) syndrome. Here, we report four families with germline DICER1 pathogenic variants in which one member in each family had a more complex phenotype, including skeletal findings, facial dysmorphism and developmental abnormalities. The developmental features occur with a variable expressivity and incomplete penetrance as also described for the neoplastic and dysplastic lesions associated with DICER1 variants. Whole exome sequencing (WES) was performed on all four cases and revealed no further pathogenic or likely pathogenic dominant, homozygous or compound heterozygous variants in three of them. Notably, a frameshift variant in ARID1B was detected in one patient explaining part of her phenotype. This series of patients shows that pathogenic DICER1 variants may be associated with a broader phenotypic spectrum than initially assumed, including predisposition to different tumours, skeletal findings, dysmorphism and developmental abnormalities, but genetic work up in syndromic patients should be comprehensive in order not to miss additional underlying /modifying causes.
Topics: Female; Humans; Germ-Line Mutation; Phenotype; Frameshift Mutation; Cysts; Ribonuclease III; Germ Cells; DEAD-box RNA Helicases
PubMed: 34331184
DOI: 10.1007/s10689-021-00271-z