Pulmonary blastoma with a good prognosis: a case report and review of the literature.

Pulmonary blastoma (PB) is a rare, highly malignant tumor prone to distant metastasis and recurrence, and the prognosis of these patients is often poor. We report a case of metastatic PB with a good prognosis with the aim of providing data to support a clinical diagnosis and treatment. In December 2015, a 43-year-old male patient was admitted to our hospital because of a cough and blood-stained sputum. Positron emission-computed tomography showed massive high-density imaging in the lower lobe of the right lung, with a maximum cross-section of 76 × 58 mm. Thoracoscopic-assisted right lower lobectomy with lymph node dissection was performed. After 1 month, computed tomography showed a high possibility of metastasis. The patient then received docetaxel and cisplatin chemotherapy for a total of six courses. After chemotherapy, enhanced computed tomography showed considerable absorption of pleural effusion, and a left lobe pulmonary nodule was not detected. The postoperative pathological diagnosis was PB, and epithelial and mesenchymal differentiation components were observed. The patient continued to visit the hospital regularly for re-examination and imaging examinations. Currently, no signs of recurrence or distant metastasis have been detected.

Estrogen Receptor Expression in DICER1-related Lesions is Associated With the Presence of Cystic Components.

DICER1 tumor predisposition syndrome results from pathogenic variants in DICER1 and is associated with a variety of benign and malignant lesions, typically involving kidney, lung, and female reproductive system. Over 70% of sarcomas in DICER1 tumor predisposition syndrome occur in females. Notably, pediatric cystic nephroma (pCN), a classic DICER1 tumor predisposition syndrome lesion, shows estrogen receptor (ER) expression in stromal cells. There are also renal, hepatic, and pancreatic lesions unassociated with DICER1 tumor predisposition syndrome that have an adult female predominance and are characterized/defined by ER-positive stromal cells. Except for pCN, the expression of ER in DICER1-associated lesions remains uninvestigated. In the present study, ER expression was assessed by immunohistochemistry in 89 cases of DICER1-related lesions and 44 lesions lacking DICER1 pathogenic variants. Expression was seen in stromal cells in pCN and pleuropulmonary blastoma (PPB) types I and Ir, whereas anaplastic sarcoma of kidney and PPB types II and III were typically negative, as were other solid tumors of non-Müllerian origin. ER expression was unrelated to the sex or age of the patient. Expression of ER showed an inverse relationship to preferentially expressed antigen in melanoma (PRAME) expression; as lesions progressed from cystic to solid (pCN/anaplastic sarcoma of kidney, and PPB types I to III), ER expression was lost and (PRAME) expression increased. Thus, in DICER1 tumor predisposition syndrome, there is no evidence that non-Müllerian tumors are hormonally driven and antiestrogen therapy is not predicted to be beneficial. Lesions not associated with DICER1 pathogenic variants also showed ER-positive stromal cells, including cystic pulmonary airway malformations, cystic renal dysplasia, and simple renal cysts in adult kidneys. ER expression in stromal cells is not a feature of DICER1 perturbation but rather is related to the presence of cystic components.

Adult Pulmonary Blastoma: A Case Report with Spectrum of Rare Manifestations.

Pulmonary blastoma (PB) is an exceedingly rare and aggressive malignant lung neoplasm that has distinct biphasic morphology. In this report, we document rare manifestations and molecular alterations in PB. A 59-year-old non-smoker female, presented with cough and hemoptysis for 4 months. The high-resolution computed tomography chest scan showed a 3.5x2.7 cm mass in the basal segment of the left lung. Positron emission tomography and computed tomography revealed a fluorodeoxyglucose avid lobulated mass in the superior segment of the lower lobe of the left lung. On core biopsy, the diagnosis of pleomorphic carcinoma in a background of adenocarcinoma was made. A definite diagnosis of pulmonary blastoma was established on the left lung lobectomy specimen based on morphological and immunohistochemical findings. Post-surgical biopsy from the scalp swelling showed metastatic deposits. On Next Generation Sequencing (NGS), in addition to conventional CTNNB1 gene mutation, new pathogenic MYCN and ATM gene mutations were detected. Post-chemotherapy, the patient was doing well after 10 months of close follow-up. PB exhibited rare associations in the form of non-smoker status, scalp metastasis, and MYCN and ATM gene mutations on NGS in addition to conventional CTNNB1 gene mutation. Large cohort studies are required to discover the incidence, significance and therapeutic implications of these co-existing pathogenic molecular alterations in PB.

Cytomorphologic and immunocytochemical characterization of pediatric pleuropulmonary blastoma with a comprehensive review of the literature.

INTRODUCTION: Pleuropulmonary blastoma (PPB) is a rare, aggressive, primary intrathoracic malignancy typically seen in infancy and early childhood. Accurate distinction from congenital cystic lung lesions is crucial due to significant prognostic and therapeutic differences. Cytologic features have rarely been described. Establishing a cytodiagnosis is challenging owing to its rarity, lack of awareness, and multiple morphologic mimics. MATERIALS AND METHODS: This was a retrospective study conducted over 8 years. The histopathology and cytopathology databases were searched for all pediatric PPB cases. The corresponding cytologic samples were reviewed to identify characteristic features that can help distinguish PPB from its mimics. RESULTS: There was a total of six cases of pediatric PPB reported during the study period. Of these, four (66.7%) presented as intrathoracic, and two (33.3%) as pleural-based masses. Cytology smears showed discretely scattered and perivascular arrangements of round-oval tumor cells with background eosinophilic stromal material. The tumor cells were mildly pleomorphic (n = 3) with round nuclei, fine chromatin, inconspicuous nucleoli, and scanty cytoplasm; however, three cases showed marked anaplasia, and one each showed necrosis and rhabdoid differentiation. On immunocytochemistry (4/6), these were positive for vimentin and desmin and negative for WT1, chromogranin, SALL4, cytokeratin, CD45, and CD99. FISH (1/6) did not show N-Myc amplification. CONCLUSIONS: Knowledge of the characteristic cytomorphological and immunocytochemical features of PPB is vital to establish a prompt and accurate cytodiagnosis with appropriate clinicoradiologic correlation.

Intraocular medulloepithelioma: an unusual and challenging entity in paediatric population.

Intraocular medulloepithelioma is a rare, congenital tumour of the non-pigmented ciliary epithelium. It most frequently arises from the ciliary body but can also have its origin from the retina, iris and optic nerve. The age when lesion first appears is typically around 2-10 years. Nearly 50-60% of patients having this lesion may also have secondary features such as cataract and neovascular glaucoma. Those with extrascleral medulloepithelioma are at risk for metastasis. Systemic correlation of the tumour with pleuropulmonary blastoma/DICER1 gene is reported in the literature. Here, we report a case of a 15 years old boy with one year history of right eye proptosis and painful red right eye along with decreased vision for one week. He was assessed and operated for cataract elsewhere three years back. The ophthalmology team managed him for endophthalmitis with intravenous antibiotics, followed by 2 sessions of cryotherapy and finally an enucleation of right eye was performed due to severe pain and no vision in the involved eye. His left eye, general physical examination and systemic evaluation were normal. Histopathology revealed the diagnosis of 'malignant teratoid medulloepithelioma'. Therefore, evaluation of systemic associations for DICER1 gene mutations was performed by the oncology team. For high risk feature of scleral invasion on histopathology, he was treated with chemotherapy. Since the tumour is of rare occurrence; an international expert team with vast research experience in PPB/DICER1 associated tumours was also contacted. He was registered in International PPB/DICER1 registry where a detailed central radiology and pathology review was performed. Genetic counseling and surveillance plan was also suggested by the international registry.

Classic biphasic pulmonary blastoma: A case report and review of the literature from 2000 to 2022.

Classic biphasic pulmonary blastoma (CBPB), a distinct type of lung cancer, is a dual-phasic tumor characterized by the co-existence of low-grade fetal adenocarcinoma and primitive mesenchymal stroma. Accounting for less than 0.1% of surgically removed lung cancers, CBPB commonly presents in individuals during their fourth to fifth decades of life, with smoking as a significant risk factor. The optimal management strategy entails surgical resection, supplemented by chemotherapy to improve prognosis. The frontline chemotherapeutic agents typically include platinum agents and etoposide, with preoperative neoadjuvant chemotherapy potentially enabling operability for initially inoperable cases. In recent years, targeted therapies, such as antiangiogenic agents, have emerged as promising new treatment strategies for CBPB. For patients exhibiting brain metastases or deemed inoperable, radiation therapy proves to be a crucial therapeutic component. CBPB prognosis is adversely affected by factors such as early metastasis, tumor size exceeding 5 cm, and tumor recurrence. In this regard, serological markers have been identified as valuable prognostic indicators. To exemplify, we recount the case of a 44-year-old female patient with CBPB, wherein serum lactate dehydrogenase levels showed significant diagnostic value. This report further incorporates a comprehensive review of CBPB literature from the past 22 years.

Targeting mutant dicer tumorigenesis in pleuropulmonary blastoma via inhibition of RNA polymerase I.

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.

Scalp metastasis of pulmonary blastoma-a rare entity: Cytomorphology with differential diagnoses.

BACKGROUND: Pulmonary blastomas are exceptionally rare tumours. These tumours behave aggressively, with a propensity to metastasise to the brain and mediastinum. A definitive diagnosis of pulmonary blastoma is challenging to obtain on cytomorphology alone. CASE REPORT: We herein describe a case of a 59-year-old female who presented with a scalp lesion. The patient was diagnosed to have pulmonary blastoma on histopathology of left lower lobectomy specimen. Fine needle aspiration cytology was done from this recently developed scalp swelling. Cytomorphology supplemented with immunocytochemistry on cell block confirmed the diagnosis of a metastatic pulmonary blastoma. CONCLUSIONS: In a known case of primary pulmonary blastoma, any newly developing lesion at any anatomical site should be carefully evaluated for metastasis. If metastasis is needled and no previous histology is available, it carries a reasonable risk of erroneous interpretation. It is essential not to overlook often subtle biphasic malignant cells on the smears, which otherwise resemble other poorly differentiated tumours. Immunocytochemistry coupled with morphology is confirmatory.

Cervical Pleuropulmonary Blastoma-like Tumor Associated With DICER1 and TP53 Mutations.

We describe a very unusual cervical tumor in a 12-yr-old patient with a clinical history indicative of DICER1 syndrome. Morphologic, immunohistochemical, and molecular genetic analysis together helped to diagnose this lesion as a cervical pleuropulmonary blastoma-like tumor, associated with TP53 and DICER1 mutations. The tumor displayed usual histologic features including mixtures of embryonal rhabdomyosarcoma, sarcomatous cartilage, compact blastema, primitive spindle cells and anaplasia, akin to type III pleuropulmonary blastoma, and trabecular and retiform patterns. In addition to expanding the phenotypic spectrum of DICER1 -associated conditions, we draw attention to genotype-phenotype correlations in DICER1 -associated tumors, particularly as they relate to the discovery of a heritable tumor predisposition syndrome.

Health-related quality of life in children and adolescents with pleuropulmonary blastoma: A report from the International PPB/DICER1 Registry.

PURPOSE: Pleuropulmonary blastoma (PPB) is the most common lung cancer of infancy and early childhood and is associated with germline DICER1 variants. Type I and Ir PPB are cystic lesions treated surgically, with a subset of children with type I receiving chemotherapy. Type II and III are more aggressive lesions, treated with surgery, intensive chemotherapy and potentially radiation. We sought to assess health-related quality of life (HRQoL) in children with PPB and known germline DICER1 variants. METHODS: Children with a diagnosis of PPB or germline DICER1 pathogenic variant without history of PPB or other DICER1-related neoplasm (DICER1+ only) were enrolled in the International PPB/DICER1 Registry. Parent reports for participants aged 2-17 years for the PedsQL v.4 and PedsQL Multidimensional Fatigue Scale v.3 were collected. Fatigue, physical, and psychosocial function scores were compared. RESULTS: Analysis included 84 participants (PPB type Ir = 20, type I = 15, type II/III = 27, DICER1+ only = 22). Total fatigue scores of participants with type I and II/III PPB were lower compared to DICER1+ only, with effect size larger in type II/III (-0.82 vs. -0.40). Total psychosocial and physical functioning scores were lower in participants with type I and type II/III PPB compared to DICER1+ only, with larger effects noted in type II/III. Female sex was suggestive of worse HRQoL for both type I/Ir and type II/III cohorts. CONCLUSIONS: These data demonstrate the importance of regular HRQoL assessment in patients with a history of PPB as well as the importance and feasibility of studying HRQoL in children with rare tumors.

Bilateral Ovarian Sertoli-Leydig Cell Tumors Harboring DICER1 Germline and Distinct Somatic Mutations: Case Report and Literature Review.

Background: DICER1 tumor predisposition syndrome is characterized by an increased risk for development of pleuropulmonary blastoma, pituitary blastoma, multinodular thyroid goiter, thyroid carcinoma, sex cord stromal tumor, cystic nephroma, embryonal rhabdomyosarcoma, and tumors of the CNS, amongst others. Of this list, only pituitary blastoma is recognized as pathognomonic for the syndrome. Case report: We describe a 15-year-old female with bilateral, asynchronous Sertoli-Leydig cell tumors (SLCT). Both tumors harbored an identical germline frameshift mutation as well as unique somatic DICER1 hot-spot point mutations. Discussion: A review of bilateral SLCTs demonstrates that all patients with available DICER1 mutation status carried a germline DICER1 mutation (100%, 9 of 9). In cases with known somatic DICER1 status on bilateral tumors, all harbored distinct somatic mutations (100%, 5 of 5). Our findings support the notion that bilateral ovarian SLCTs are indeed separate events and do not represent recurrent or metastatic disease.

Imaging of pediatric pulmonary tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Pediatric pulmonary malignancy can be primary or metastatic, with the latter being by far the more common. With a few exceptions, there are no well-established evidence-based guidelines for imaging pediatric pulmonary malignancies, although computed tomography (CT) is used in almost all cases. The aim of this article is to provide general imaging guidelines for pediatric pulmonary malignancies, including minimum standards for cross-sectional imaging techniques and specific imaging recommendations for select entities.

[DICER1 syndrome: clinical variety endocrine manifestations and features of diagnostics].

DICER1 syndrome is a rare genetic disorder with the progressive development of malignant and non-malignant diseases in childhood. The cause of this syndrome is a dusfunction of the endoribonuclease DICER, which plays an important role in the processing of microRNAs with subsequent regulation of the control of the expression of oncogenes and tumor suppressor genes. Clinical manifestations of dyseropathies is very different and may include both endocrine manifestations - multinodular goiter, differentiated thyroid cancers, ovarian stromal tumors, pituitary blastoma, and non-endocrine formations - pleuropulmonary blastoma, cystic nephroma, pineoblastoma. The presence of somatic mutations of the DICER1 gene is a resultant stage in the pathogenesis of dyseropathies, determining the further path of oncogenesis. At present, DICER1 syndrome is diagnosed extremely rarely, which leads to late detection of the components of the disease in the patient, late diagnosis of neoplasms, lack of family counseling. Diagnosis at the early stages of the disease, the development of screening programs for the management of these patients allows minimizing the risks of developing more malignant, aggressive forms of the disease.

[Pleuropneumoblastoma: a case report about a rare pediatric tumor]. / Pleuropneumoblastome: une tumeur pédiatrique rare (à propos d'un cas).

Pleuropulmonary blastoma is a rare intrathoracic tumor in children. It is associated with poor prognosis and diagnosis is based on histological examination. We conducted a didactic study involving a 3-year-old child with severe acute respiratory distress associated with hemothorax; radiological and thoracoscopic examination suggested malignant pleuropulmonary process. Anatomopathological examination with radio-clinical comparison allowed for the diagnosis of solid-cystic pleuropulmonary blastoma type II. Unfortunately, given the severity of the clinical features, the child died within a few weeks due to multiple organ failure. Pathologist experience is very important to recognize the disease and to start adequate treatment as soon as possible. This allows for a tumor regression rate up to 90% after neoadjuvant treatment and a 5-year survival rate of at least 53% for aggressive forms: solid and solido-cystic tumors.

Pleuropulmonary blastoma masquerading as pneumothorax in a patient with a ventricular septal defect.

Pleuropulmonary blastoma is a rare pediatric primary lung tumor. We report a case of a child with Down syndrome and a large ventricular septal defect presenting with pleuropulmonary blastoma initially misdiagnosed as spontaneous pneumothorax. Following tube thoracostomy drainage of the pneumothorax, the child underwent surgical closure of the ventricular septal defect. However, the postoperative period was complicated by recurrent left pleural collection requiring prolonged intercostal tube drainage and two thoracotomies to evacuate the necrotic pleural material. The biopsy of the necrotic material was suggestive of type III pleuropulmonary blastoma. In view of the high propensity of metastasis associated with this variant of a tumor, the patient was started on chemotherapy. This case report highlights the possibility of pleuropulmonary blastoma presenting as pneumothorax and emphasizes the need to consider the etiology, before intervening in a child presenting with spontaneous pneumothorax.

Pleuropulmonary blastoma (PPB) and other DICER1-associated high-grade malignancies are morphologically, genetically and epigenetically related - A comparative study of 4 PPBs and 6 sarcomas.

DICER1-related tumors occur hereditary or sporadically, with high-grade malignancies sharing clinicopathological and (epi)genetic features. We compared 4 pleuropulmonary blastomas (PPBs) and 6 sarcomas by mutation analysis, whole transcriptome sequencing and methylation profiling. 9/10 patients were female. PPB patients were 0-4 years. 3/4 were alive; 2 without disease. One patient died of metastatic disease (median follow-up, 16 months). Sarcoma patients were 16-56 years. Locations included: uterine cervix/corpus (3/1), soft tissue back/shoulder (1) and paravertebral (1). 5/6 patients were alive; 2 developed metastases: intracranial (1) and lung and kidney (1) (median follow-up, 17 months). The deceased patient previously had a PPB and a Sertoli-Leydig cell tumor. Histologically, tumors showed atypical primitive-looking cells with incomplete rhabdomyoblastic differentiation and cartilage (n = 5). Immunohistochemistry demonstrated desmin- (n = 9/10), myogenin- (n = 6/10) and keratin positivity (n = 1/1). Eight cases harbored biallelic DICER1 mutations with confirmed germline mutations in 4 cases. Two cases showed a monoallelic mutation. By RNA expression- and methylation profiling, distinct clustering of our cases was seen demonstrating a close relationship on (epi)genetic level and similarities to embryonal rhabdomyosarcoma. In conclusion, this study shows overlapping morphological, immunohistochemical and (epi)genetic features of PPBs and DICER1-associated high-grade sarcomas, arguing that these neoplasms form a spectrum with a broad clinicopathological range.

Pulmonary blastoma in a pregnant woman: a case report and brief review of the literature.

BACKGROUND: Pulmonary blastoma (PB) comprises a rare heterogeneous group of lung tumours typically containing immature epithelial and mesenchymal structures that imitate the embryonic lung tissue and extremely rarely occurs during pregnancy. Although cough and haemoptysis are the most common PB symptoms, they usually indicate other serious pregnancy-related complications. CASE PRESENTATION: The article presents the unusual case of a 22-year-old pregnant woman diagnosed with PB during pregnancy. CONCLUSIONS: PB is characterized by poor prognosis and patients' outcome relies on a rapid diagnosis. Surgery remains the most common and effective treatment. Due to the extreme rarity, the literature contains only single mentions of PB in pregnancy, thus its impact on the course of pregnancy and the developing fetus remains unknown.

DICER1-Mutated Botryoid Fibroepithelial Polyp of the Parotid Duct: Report of the First Case.

DICER1, a member of the ribonuclease III family, is involved in the biogenesis of microRNAs and, hence, it influences gene expression regulation. DICER1 germline (associated with the inherited DICER1 syndrome) or somatic mutations have been linked to tumorigenesis in histogenetically diverse benign and malignant neoplasms in different organs including pleuropulmonary blastoma, cystic nephroma, embryonal rhabdomyosarcoma, nasal chondromesenchymal hamartoma, poorly differentiated thyroid carcinoma, thyroblastoma, intracranial sarcoma and gonadal Sertoli-Leydig cell tumors in addition to others. Moreover, rare botryoid (giant) fibroepithelial polyps may harbor this mutation. Herein, we describe the first reported case of a DICER1-mutated botryoid fibroepithelial polyp occurring within the parotid duct of a 65-year-old female who has no other features or family history of the DICER1 syndrome. Based on its distinctive morphology, we tested this lesion specifically for DICER1 mutations and confirmed the presence of a pathogenic DICER1 variant with a low allele frequency, consistent with a somatic mutation.

Phenotypic similarities within the morphologic spectrum of DICER1-associated sarcomas and pleuropulmonary blastoma: Histopathologic features guide diagnosis in the LMIC setting.

Extrapulmonary DICER1-associated sarcomas (DS) can harbor morphological features overlapping with pleuropulmonary blastoma. We report three children with intracranial and genital tract sarcomas, suspected to have DS based on a heterogeneous yet defining combination of spindle-cell sarcomatous and blastemal morphology, with rhabdomyomatous differentiation. Foci of immature cartilage at diagnosis (n = 2/3) and increased neuroepithelial differentiation at recurrence (n = 1) were noted. Morphological suspicion prompted somatic testing at reference centers, confirming likely biallelic, loss-of-function, and "hotspot" missense DICER1 variants in all three tumors. This can serve as a model for this diagnosis in resource-limited settings and has implications for germline testing, surveillance, and tumor management.