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Li WQ, Wu HX, Li HB, Shen Y. Uterine myxoid leiomyosarcoma: identification of a novel PLAG1 fusion partner. Pathology 2024; 56:753-755. [PMID: 38599959 DOI: 10.1016/j.pathol.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/05/2024] [Accepted: 01/16/2024] [Indexed: 04/12/2024]
Affiliation(s)
- Wen-Qi Li
- Department of Pathology, Tianjin Central Hospital of Obstetrics and Gynecology, Tianjin, China
| | - Hai-Xia Wu
- Department of Pathology, Tianjin Central Hospital of Obstetrics and Gynecology, Tianjin, China
| | - Han-Bo Li
- Department of Pathology, Tianjin Central Hospital of Obstetrics and Gynecology, Tianjin, China
| | - Yan Shen
- Department of Pathology, Tianjin Central Hospital of Obstetrics and Gynecology, Tianjin, China.
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2
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Michal M, Agaimy A, Croce S, Mechtersheimer G, Gross JM, Xing D, Bell DA, Gupta S, Mosaieby E, Martínek P, Klubíčková N, Michalová K, Bouda J, Fínek J, Hernandez T, Michal M, Schoolmeester JK, Ondič O. PLAG1-Rearranged Uterine Sarcomas: A Study of 11 Cases Showing a Wide Phenotypical Spectrum Not Limited to Myxoid Leiomyosarcoma-like Morphology. Mod Pathol 2024:100552. [PMID: 38942115 DOI: 10.1016/j.modpat.2024.100552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Revised: 06/07/2024] [Accepted: 06/20/2024] [Indexed: 06/30/2024]
Abstract
PLAG1 gene fusions were recently identified in a subset of uterine myxoid leiomyosarcomas (M-LMS). However, we have encountered cases of PLAG1-rearranged uterine sarcomas (PLAG1-US) lacking M-LMS-like morphology and/or any expression of smooth muscle markers. To better characterize their clinicopathological features, we performed a multi-institutional search which yielded 11 cases. The patients ranged in age from 34-72 years (mean: 57). All tumors arose in the uterine corpus, ranging in size from 6.5-32 cm (mean: 15). The most common stage at presentation was pT1b (n=6), three cases had stage pT1 (unspecified) and one case each presented in stage pT2a and pT3b. Most were treated only by hysterectomy with adnexectomy. The follow-up (range: 7-71 months; median: 39 months) was available for 7 patients. Three cases (7-21 months of follow-up) had no evidence of disease. Three out of 4 remaining patients died of disease within 55-71 months, while the last developed peritoneal spread and was transferred for palliative care at 39 months. Morphologically, the tumors showed a high inter- and intratumoral heterogeneity. M-LMS-like and epithelioid LMS-like morphology was present in 3 and 5 primary tumors, respectively, the rest mostly presented as non-descript ovoid/spindle cell sarcomas. Unusual morphological findings included prominently hyalinized stroma (n=3), adipocytic differentiation with areas mimicking myxoid liposarcoma (n=2), osteosarcomatous differentiation (n=1) and undifferentiated pleomorphic sarcoma-like areas (n=1). The mitotic activity ranged from 3-24 mitoses/10 high-power fields (mean: 9), 3/10 cases showed necrosis. In 3/11 cases, no expression of SMA, h-caldesmon or desmin was noted, whereas 5/5 cases expressed PLAG1. By RNA-sequencing, the following fusion partners were identified: PUM1, CHCHD7 (each n=2), C15orf29, CD44, MYOCD, FRMD6, PTK2 and TRPS1 (each n=1). One case only showed PLAG1 gene break by FISH. Our study documents a much broader morphological spectrum of PLAG1-US than previously reported, encompassing but not limited to M-LMS-like morphology with occasional heterologous (particularly adipocytic) differentiation. Since it is currently difficult to precisely define their line of differentiation, for the time being, we suggest using a descriptive name PLAG1-rearranged uterine sarcoma.
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Affiliation(s)
- Michael Michal
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic.
| | - Abbas Agaimy
- Institute of Pathology, Friedrich-Alexander University Erlangen-Nürnberg, University Hospital, Erlangen, Germany
| | - Sabrina Croce
- Department of BioPathology, Anticancer Center, Institut Bergonié, Bordeaux, France
| | | | - John M Gross
- Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
| | - Deyin Xing
- Departments of Pathology, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
| | - Debra A Bell
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Sounak Gupta
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Elaheh Mosaieby
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic
| | | | - Natálie Klubíčková
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic
| | - Květoslava Michalová
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic
| | - Jiří Bouda
- Department of Gynecology and Obstetrics, Medical Faculty Pilsen, Charles University and Charles University Hospital Pilsen, Czech Republic
| | - Jindřich Fínek
- Department of Oncology and Radiotherapeutics, Charles University, Faculty of Medicine in Plzen, Czech Republic
| | - Tahyna Hernandez
- Department of Pathology and Laboratory Medicine, Zucker School of Medicine at Hofstra/Northwell, Pathology and Laboratory Medicine, Hempstead, N.Y, USA
| | - Michal Michal
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic
| | | | - Ondrej Ondič
- Bioptical Laboratory, Ltd., Plzen, Czech Republic; Department of Pathology, Charles University, Faculty of Medicine in Plzen, Czech Republic
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3
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Albalawi E. Genetic Rearrangements in Different Salivary Gland Tumors: A Systematic Review. Cureus 2024; 16:e61639. [PMID: 38966479 PMCID: PMC11223175 DOI: 10.7759/cureus.61639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2024] [Indexed: 07/06/2024] Open
Abstract
Salivary gland tumors (SGT) encompass a wide range of neoplasms, each with its own unique histological type and clinical presentation. This review hones in on prevalent subtypes of SGTs, including adenoid cystic carcinoma (ACC), salivary duct carcinoma (SDC), and polymorphous adenocarcinoma (PAC). The articles, identified through specific keywords, were meticulously screened in databases like PubMed, Scopus, Google Scholar, and Web of Science from 2018 to 2023. Eight articles delved into genetic modifications among the selected SGT types. A fusion protein known as MYB-NF1B is typically associated with ACC, promoting cell proliferation while inhibiting apoptosis. The presence of MYB modifications in ACCs is a beacon of hope, as it is linked to a more favorable prognosis. In contrast, SDCs often exhibit HER2 expression. The invasive nature of SGTs contributes to their resistance to treatment. In the case of PAC, the role of PRKD1 is particularly noteworthy. PRKD1, integrated with other genes from the PRKD1/2/3 cluster, helps to differentiate PAC from other diseases. Furthermore, the genetic profiles of KTN1-PRKD1) and PPP2R2A:PRKD1 are distinct. The significant genetic variability among SGTs necessitates meticulous examination. This field is in a constant state of evolution, with new discoveries reshaping our understanding. Genetics is a key player in deciphering SGTs and tailoring treatments. This complex neoplasm demands ongoing research to uncover all genetic influences, thereby enhancing diagnostic methodologies, therapeutic strategies, and patient outcomes.
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4
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Kosemehmetoglu K, Mosaieby E, Šteiner P, Vaněček T, Baranovska-Andrigo V, Michal M. Calcifying Spindle Cell Soft Tissue Tumor With SOX10::PLAG1 Fusion: A Case Report of a Morphologically Distinctive and Potentially Novel Soft Tissue Tumor. Genes Chromosomes Cancer 2024; 63:e23249. [PMID: 38884173 DOI: 10.1002/gcc.23249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/02/2024] [Accepted: 05/14/2024] [Indexed: 06/18/2024] Open
Abstract
The widespread use of advanced molecular techniques has led to the identification of several tumor types with PLAG1 gene fusions some of which also affect the skin and soft tissues. Herein, we present a 38-year-old female with a subcutaneous tumor affecting her forearm, which does not seem to fit into any currently recognized entity. It was a well-circumscribed tumor measuring 6 × 4,5 × 4 cm. It had a thick capsule composed of bland spindle cells forming palisades and Verocay body-like structures within a myxocollagenous background. Scattered calcifications were dispersed throughout the lesion. No cytological atypia, mitotic activity, or necrosis were present. Targeted NGS revealed a SOX10::PLAG1 fusion and fluorescent in situ hybridization confirmed the presence of PLAG1 gene rearrangement. The neoplastic cells showed a diffuse immunohistochemical expression of S100, SOX10, and PLAG1, as well as patchy desmin and CD34 positivity. The methylation profile of this tumor did not match any other entity covered by the DKFZ sarcoma classifier and apart from the gain of chromosome 12, the copy number profile was normal. The tumor was completely excised, and the patient has been free of disease for 4 years since the excision. While more cases are needed to confirm this tumor as a distinct entity, we propose a provisional name "SOX10::PLAG1-rearranged calcifying spindle cell tumor."
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Affiliation(s)
- Kemal Kosemehmetoglu
- Department of Pathology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | | | - Petr Šteiner
- Bioptica Laboratory, Ltd., Plzen, Czech Republic
| | | | - Vira Baranovska-Andrigo
- Department of Pathology, Charles University, Faculty of Medicine in Plzen, Plzen, Czech Republic
| | - Michael Michal
- Bioptica Laboratory, Ltd., Plzen, Czech Republic
- Department of Pathology, Charles University, Faculty of Medicine in Plzen, Plzen, Czech Republic
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5
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Cua SKN, Odoño EG, Chan KIP, Casanova DEG, Guerzon A, Khu KJO. Pediatric fibromyxoid brachial plexus tumor with YWHAZ::PLAG1 gene fusion: a case report. Childs Nerv Syst 2024; 40:1919-1924. [PMID: 38459146 DOI: 10.1007/s00381-024-06359-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 03/04/2024] [Indexed: 03/10/2024]
Abstract
Pediatric fibromyxoid soft tissue tumors may be associated with gene fusions such as YHWAZ::PLAG1, with only three reported cases in the literature. We present the fourth case, a 13-year-old male with a pediatric fibromyxoid brachial plexus tumor with YWHAZ::PLAG1 gene fusion. This is also the first case to be reported in an adolescent, in the brachial plexus, and in the Philippines. The patient presented with a 10-year history of a slowly growing left supraclavicular mass and a 1-year history of intermittent dysesthesia in the left upper extremity. Neurologic examination was unremarkable. Imaging revealed a large left supraclavicular lesion with intrathoracic extension. Surgical excision was performed, and histopathology revealed a fibromyxoid tumor with YWHAZ::PLAG1 gene fusion. Although previous examples of this gene fusion pointed toward lipoblastoma as their primary pathology, our tumor does not completely fulfill the current diagnostic criteria for a lipoblastoma and may represent an intermediate form of the disease. Our case is unique not only because it is the first reported adolescent patient harboring such a lesion but also because of the relatively lengthy natural history exhibited by the tumor prior to its resection. This provided us with valuable information about its behavior, which suggests a more indolent growth pattern. This case also highlights the clinical importance of molecular testing of tumors, where recognition of disease entities can assist clinicians in deciding and advocating for the proper management.
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Affiliation(s)
- Sean Kendrich N Cua
- Division of Neurosurgery, Department of Neurosciences, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Eugene G Odoño
- Division of Pathology, Department of Laboratories, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Kevin Ivan P Chan
- Division of Neurosurgery, Department of Neurosciences, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Dondiego Eleazar G Casanova
- Division of Pathology, Department of Laboratories, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Aileen Guerzon
- Department of Pediatrics, Bicol Medical Center, Naga, Philippines
| | - Kathleen Joy O Khu
- Division of Neurosurgery, Department of Neurosciences, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.
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Deolet E, Cordier F, Ferdinande L, Loontiens S, Van der Meulen J, Van Dorpe J, Creytens D. A case of a lipoblastoma with EEF1A1::PLAG1 fusion and metaplastic ossification. Genes Chromosomes Cancer 2024; 63:e23225. [PMID: 38470300 DOI: 10.1002/gcc.23225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 01/19/2024] [Indexed: 03/13/2024] Open
Affiliation(s)
- Ellen Deolet
- Department of Pathology, Ghent University Hospital, Ghent, Belgium
| | - Fleur Cordier
- Department of Pathology, Ghent University Hospital, Ghent, Belgium
- CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium
| | | | - Siebe Loontiens
- CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium
- Molecular Diagnostics Ghent University Hospital (MDG), Ghent University Hospital, Ghent University, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Joni Van der Meulen
- CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium
- Molecular Diagnostics Ghent University Hospital (MDG), Ghent University Hospital, Ghent University, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Jo Van Dorpe
- Department of Pathology, Ghent University Hospital, Ghent, Belgium
- CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium
| | - David Creytens
- Department of Pathology, Ghent University Hospital, Ghent, Belgium
- CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium
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7
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Lanceta J, Tripodi J, Karp L, Shaham M, Mahmood N, Najfeld V, Edelman M, Cohen N. Chromothripsis in lipoblastoma: second reported case with complex PLAG1 rearrangement. Mol Cytogenet 2023; 16:32. [PMID: 38012697 PMCID: PMC10683218 DOI: 10.1186/s13039-023-00665-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/14/2023] [Indexed: 11/29/2023] Open
Abstract
Lipoblastomas (LPBs) are rare benign neoplasms derived from embryonal adipose that occur predominantly in childhood. LPBs typically present with numeric or structural rearrangements of chromosome 8, the majority of which involve the pleomorphic adenoma gene 1 (PLAG1) proto-oncogene on chromosome 8q12. Here, we report on a LPB case on which showed evidence of chromothripsis. This is the second reported case of chromothripsis in LPB.
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Affiliation(s)
- Joel Lanceta
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA.
| | - Joseph Tripodi
- Tumor CytoGenomics, Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lynne Karp
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA
- Division of Cytogenetics and Molecular Pathology, North Shore University Hospital, Manhasset, NY, USA
| | - Meira Shaham
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA
- Division of Cytogenetics and Molecular Pathology, North Shore University Hospital, Manhasset, NY, USA
| | - Nayyara Mahmood
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA
- Division of Cytogenetics and Molecular Pathology, North Shore University Hospital, Manhasset, NY, USA
| | - Vesna Najfeld
- Tumor CytoGenomics, Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Morris Edelman
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA
- Division of Pediatric Pathology, Cohen Children's Medical Center, New Hyde Park, NY, USA
| | - Ninette Cohen
- Department of Pathology and Laboratory Medicine, Northwell Health/Donald and Barbara Zucker School of Medicine at Hofstra, Manhasset, New York, USA
- Division of Cytogenetics and Molecular Pathology, North Shore University Hospital, Manhasset, NY, USA
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8
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Tyra J, Mierzwińska-Dolny P, Fishman AJ, Mierzwiński J. Head and neck lipoblastoma in children: A case report and systematic review. Int J Pediatr Otorhinolaryngol 2023; 173:111699. [PMID: 37597314 DOI: 10.1016/j.ijporl.2023.111699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 07/26/2023] [Accepted: 08/14/2023] [Indexed: 08/21/2023]
Abstract
BACKGROUND Lipoblastoma is a rare and benign tumor arising from embryonal fat cells. It develops primarily in infancy and early childhood. We present a case study of a 10-month-old child treated for an extensive tumor of the infratemporal fossa and parapharyngeal space. The systematic review of 60 reports in 80 children with lipoblastoma of the head and neck is also reported. MATERIAL AND METHODS Systematic review of all articles included lipoblastomas of the head and neck area in children published from 1964 to 2022 in the PubMed database was conducted. Clinical presentation of extensive lipoblastoma of the head and neck in a child. RESULTS On the basis of all inclusion criteria 83 articles were identified concerning pediatric lipoblastoma. There were 36 F (45%) and 39 M (48%), in 6 patients, (7%) gender was not specified. Ages ranged from 0mth (6h) to 15 yo (180mth). The tumor was located in the head in 22 (27%) cases, while the neck area accounted for 53 (65%) cases. General description without precise location was shown in 6 (7%) cases. All patients underwent complete surgical excision. Post surgical recurrence was noted in 6% clinical cases in the analyzed articles. CONCLUSIONS Lipoblastoma is characterized by a rapidly growing predominantly adipose mass. The treatment of choice is complete surgical excision. In selected cases when the pathology is hard to reach, as a consequence of the extensive penetration of the mass, we recommend performing the procedure with an interdisciplinary team. Endoscopy assistance and microdebrider significantly facilitated the removal of pathology in the described advanced case of lipoblastoma. This is the only case reported in the pediatric literature of a head and neck lipoblastoma, where due to extensive involvement and location of the disease the cranial nerves V2 and inferior alveolar branch of V3 could not be spared. Long-term follow-up even to 10 years is required because there is a reported tendency for these tumors to recur.
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Affiliation(s)
- Justyna Tyra
- Children's Hospital of Bydgoszcz, Department of Otolaryngology, Audiology and Phoniatrics, Pediatric Cochlear Implant Program, Bydgoszcz, Poland
| | - Paulina Mierzwińska-Dolny
- Children's Hospital of Bydgoszcz, Department of Otolaryngology, Audiology and Phoniatrics, Pediatric Cochlear Implant Program, Bydgoszcz, Poland; University Clinical Center, Gdańsk, Poland.
| | - Andrew J Fishman
- University of Missouri, Department of Otolaryngology Head & Neck Surgery, Columbia, MO, USA; ACIBADEM BelMedic Clinical Center, Department of ORL-Neurosurgery, Belgrade, Serbia
| | - Józef Mierzwiński
- Children's Hospital of Bydgoszcz, Department of Otolaryngology, Audiology and Phoniatrics, Pediatric Cochlear Implant Program, Bydgoszcz, Poland; Nicolaus Copernicus University, Collegium Medicum, Department of Developmental Age Diseases, Bydgoszcz, Poland
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9
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Anderson WJ, Mariño-Enríquez A, Trpkov K, Hornick JL, Nucci MR, Dickson BC, Fletcher CDM. Expanding the Clinicopathologic and Molecular Spectrum of Lipoblastoma-Like Tumor in a Series of 28 Cases. Mod Pathol 2023; 36:100252. [PMID: 37355153 DOI: 10.1016/j.modpat.2023.100252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/14/2023] [Accepted: 06/14/2023] [Indexed: 06/26/2023]
Abstract
Lipoblastoma-like tumor (LLT) is a rare adipocytic neoplasm with a predilection for the vulva. Since 2002, <30 cases have been reported, characterizing it as an indolent tumor that may sometimes recur locally. Diagnosis can be challenging due to its rarity and morphologic overlap with other adipocytic tumors. Thus far, there are no specific molecular or immunohistochemical features to aid in the diagnosis of LLT. Recent case reports have described LLT arising at other sites, including the spermatic cord and gluteal region, suggesting wider anatomical distribution. We present a large series of LLT to further characterize its clinicopathologic and molecular features. Twenty-eight cases of LLT were retrieved from departmental and consult archives (including 8 from a prior series). The cohort comprised 28 patients (8 males, 20 females) with a median age of 28 years (range: 1-80 years). There were 17 primary LLT of the vulva. Other anatomical sites included the scrotum (n = 3), spermatic cord (n = 2), inguinal region (n = 2), limbs (n = 2), pelvis (n = 1), and retroperitoneum (n = 1). Median tumor size was 6.0 cm (range: 1.8-30.0 cm). The tumors had a lobulated architecture and were typically composed of adipocytes, lipoblasts, and spindle cells in a myxoid stroma with prominent thin-walled vessels. Using immunohistochemistry, a subset showed loss of Rb expression (12/23 of samples). Follow-up in 15 patients (median: 56 months) revealed 8 patients with local recurrence and 1 patient with metastases to the lung/pleura and breasts. Targeted DNA sequencing revealed a simple genomic profile with limited copy number alterations and low mutational burden. No alterations in RB1 were identified. The metastatic LLT showed concurrent pathogenic PIK3CA and MTOR activating mutations, both in the primary and in the lung/pleural metastasis; the latter also harbored TERT promoter mutation. One tumor had a pathogenic TSC1 mutation, and one tumor showed 2-copy deletion of CDKN2A, CDKN2B, and MTAP. No biologically significant variants were identified in 8 tumors. No gene fusions were identified by RNA sequencing in 4 tumors successfully sequenced. This study expands the clinicopathologic spectrum of LLT, highlighting its wider anatomical distribution and potential for occasional metastasis. Molecularly, we identified activating mutations in the PI3K-MTOR signaling pathway in 2 tumors, which may contribute to exceptional aggressive behavior.
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Affiliation(s)
- William J Anderson
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Adrian Mariño-Enríquez
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Kiril Trpkov
- Department of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jason L Hornick
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Marisa R Nucci
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Brendan C Dickson
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Christopher D M Fletcher
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
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10
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Schieffer KM, Moccia A, Bucknor BA, Stonerock E, Jayaraman V, Jenkins H, McKinney A, Koo SC, Mathew MT, Mardis ER, Lee K, Reshmi SC, Cottrell CE. Expanding the Clinical Utility of Targeted RNA Sequencing Panels beyond Gene Fusions to Complex, Intragenic Structural Rearrangements. Cancers (Basel) 2023; 15:4394. [PMID: 37686670 PMCID: PMC10486946 DOI: 10.3390/cancers15174394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
Gene fusions are a form of structural rearrangement well established as driver events in pediatric and adult cancers. The identification of such events holds clinical significance in the refinement, prognostication, and provision of treatment in cancer. Structural rearrangements also extend beyond fusions to include intragenic rearrangements, such as internal tandem duplications (ITDs) or exon-level deletions. These intragenic events have been increasingly implicated as cancer-promoting events. However, the detection of intragenic rearrangements may be challenging to resolve bioinformatically with short-read sequencing technologies and therefore may not be routinely assessed in panel-based testing. Within an academic clinical laboratory, over three years, a total of 608 disease-involved samples (522 hematologic malignancy, 86 solid tumors) underwent clinical testing using Anchored Multiplex PCR (AMP)-based RNA sequencing. Hematologic malignancies were evaluated using a custom Pan-Heme 154 gene panel, while solid tumors were assessed using a custom Pan-Solid 115 gene panel. Gene fusions, ITDs, and intragenic deletions were assessed for diagnostic, prognostic, or therapeutic significance. When considering gene fusions alone, we report an overall diagnostic yield of 36% (37% hematologic malignancy, 41% solid tumors). When including intragenic structural rearrangements, the overall diagnostic yield increased to 48% (48% hematologic malignancy, 45% solid tumor). We demonstrate the clinical utility of reporting structural rearrangements, including gene fusions and intragenic structural rearrangements, using an AMP-based RNA sequencing panel.
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Affiliation(s)
- Kathleen M. Schieffer
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Amanda Moccia
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Brianna A. Bucknor
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Eileen Stonerock
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Vijayakumar Jayaraman
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Heather Jenkins
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Aimee McKinney
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
| | - Selene C. Koo
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, OH 43205, USA
| | - Mariam T. Mathew
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Elaine R. Mardis
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Kristy Lee
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Shalini C. Reshmi
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Catherine E. Cottrell
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children’s Hospital, Columbus, OH 43215, USA
- Department of Pathology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
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11
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Aldawood Z, Al-Ibraheemi A. Lipoblastoma Arising in the Head and Neck: A Clinicopathologic Analysis of 20 Cases. Head Neck Pathol 2023; 17:768-774. [PMID: 37486535 PMCID: PMC10514009 DOI: 10.1007/s12105-023-01575-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 07/08/2023] [Indexed: 07/25/2023]
Abstract
BACKGROUND Lipoblastomas (LPBs) are benign adipocytic neoplasms believed to recapitulate the development of embryonal fat. METHODS We investigated the clinicopathologic and immunohistochemical features of 20 lipoblastomas arising in the head and neck in 18 patients. RESULTS Patients included 6 males and 12 females (1:2 ratio) with age at diagnosis ranging from 4 months to 28 years. Tumors occurred more commonly in the neck (12, 66.7%) and less commonly in the forehead, scalp, and tongue (2, 11.1%). Tumor size ranged from 1.4 to 6.0 cm (median 5.0 cm). Two patients, a 4-month-old female and 3-year-old male, had local recurrence of neck tumors at 4 months and 3 years after excision, respectively. Microscopically, tumors had a lobulated growth pattern and consisted of adipocytes at varying stages of differentiation. In addition to the classical histologic features, lipoma-like and myxoid variants constituted 45% of cases. Metaplastic elements, including brown fat and cartilage, were identified in two cases. CONCLUSIONS LPBs arising in the head and neck region are not uncommon and occurred at a rate of 9% in our cohort. They should be kept in the differential diagnosis when a fatty tumor is encountered in an older child or occurring at an unusual location.
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Affiliation(s)
- Zahra Aldawood
- Department of Biomedical Dental Science, College of Dentistry, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, Saudi Arabia
| | - Alyaa Al-Ibraheemi
- Department of Pathology, Children's Hospital Boston and Harvard Medical School, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA.
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12
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Bady EE, Schwartz TR, Tibesar R. A Teenager With Dysphagia, Mild Dyspnea, and an Indolent Mass. JAMA Otolaryngol Head Neck Surg 2023; 149:754-755. [PMID: 37382925 DOI: 10.1001/jamaoto.2023.1415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
A 15-year-old male presented with dysphagia to solid foods, and dyspnea when laying on the right side that had progressed during 8 months. What is your diagnosis?
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Affiliation(s)
- Ebone Evans Bady
- Otolaryngology-Head and Neck Surgery, University of Minnesota, Minneapolis
| | - Tyler R Schwartz
- Pediatric Ear, Nose, and Throat, and Facial Plastic Surgery, Children's Hospital of Minnesota, Saint Paul
| | - Robert Tibesar
- Pediatric Ear, Nose, and Throat, and Facial Plastic Surgery, Children's Hospital of Minnesota, Saint Paul
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13
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de Jager VD, de Visscher SAHJ, Schuuring E, Doff JJ, van Kempen LC. A novel PPP2R2A::PRKD1 fusion in a cribriform adenocarcinoma of salivary gland. Genes Chromosomes Cancer 2023; 62:297-300. [PMID: 36625487 DOI: 10.1002/gcc.23122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 01/03/2023] [Accepted: 01/08/2023] [Indexed: 01/11/2023] Open
Abstract
Cribriform adenocarcinoma of salivary gland (CASG) is a rare, salivary gland tumor. In this report, we describe a case of CASG harboring a novel PPP2R2A::PRKD1 fusion. A 58-year-old female presented with an intraoral mass adjacent to the lower left third molar region. Morphological features at histological examination, immunohistochemical staining (p63+, p40-), and tumor location were indicative of CASG. However, due to the potential focal presence of a biphasic component within the tumor, RNA sequencing was performed to confirm the diagnosis. The subsequently found novel PPP2R2A::PRKD1 fusion adds to the rapidly evolving molecular landscape of salivary gland tumors. Additionally, we report that CASG may show some entrapment of pre-existent salivary gland ducts, which may be misinterpreted as tumor cells with myoepithelial differentiation.
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Affiliation(s)
- Vincent D de Jager
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Sebastiaan A H J de Visscher
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Ed Schuuring
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jan J Doff
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Léon C van Kempen
- Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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14
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Zhang Z, Lu Y, Shi C, Chen M, He X, Zhang H. Pediatric dermatofibrosarcoma protuberans: A clinicopathologic and genetic analysis of 66 cases in the largest institution in Southwest China. Front Oncol 2023; 13:1017154. [PMID: 36776313 PMCID: PMC9916051 DOI: 10.3389/fonc.2023.1017154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 01/02/2023] [Indexed: 01/28/2023] Open
Abstract
Background Dermatofibrosarcoma protuberans (DFSP) is an uncommon cutaneous tumor in children. Most published articles are sporadic or small series and lack systematically molecular analyses. The aim of our study is to better understand the clinicopathologic and genetic features of these rare lesions. Methods All patients diagnosed with DFSP aged ≤ 18 years were retrospectively reviewed from January 2006 to May 2022. Results A total of 66 cases (32 male and 34 female patients) were identified, with ages ranging from 0.3 to 18 years (median, 13 years). Tumor locations predominantly occurred on the trunk (38/66, 57.6%), followed by the extremities (20/66, 30.3%) and head/neck (8/66, 12.1%). Histological findings revealed classic (41/66, 62.1%), myxoid (4/66, 6.1%), pigmented (6/66, 9.1%), plaque-like (3/66, 4.5%), giant cell fibroblastoma (GCF; 6/66, 9.1%), and fibrosarcomatous (6/66, 9.1%) variants of DFSP. Immunochemistry revealed minority tumors (9/66, 13.6%) showing patchy or negative staining for CD34. Fluorescence in situ hybridization (FISH) indicated that 49 of 53 tested cases including all detected biopsy specimens (11/11) contained COL1A1-PDGFB fusion, in which the average copy number gain of COL1A1-PDGFB was 0.68. There were four cases negative for COL1A1-PDGFB rearrangement, one of which was found to harbor a novel COL3A1-PDGFB fusion by next-generation sequencing (NGS). Treatment for 63 patients comprised 40 marginal excisions and 23 wide local excisions (WLEs), including 1 with imatinib therapy. Follow-up information was available on 49 patients with a duration of 12-161 months (median, 60 months). Fourteen patients developed tumor recurrence, all with initial marginal excisions. The others survived with no evidence of disease. Conclusions This study of pediatric DFSP indicates certain discrepancies in clinicopathologic characteristics between children and adults. The majority of pediatric DFSPs contain COL1A1-PDGFB fusion, the same as their adult counterparts. The COL3A1-PDGFB chimerism might be associated with the special morphology of GCF, which needs further investigation. FISH is valuable in biopsy tissues and cases with atypical CD34 immunostaining, while supplementary NGS could be helpful to identify the cytogenetically cryptic DFSP. Overall, an urgent accurate diagnosis is needed to formulate an optimal therapeutic strategy in the pediatric population.
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Affiliation(s)
- Zhang Zhang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
| | - Yang Lu
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
| | - Changle Shi
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
| | - Min Chen
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
| | - Xin He
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
| | - Hongying Zhang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, China
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15
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Zhang W, Zhang S, Yang Z, Zhang Y, Wang Z. Lipoblastoma in one adult and 35 pediatric patients: Retrospective analysis of 36 cases. Exp Ther Med 2022; 25:11. [PMID: 36561624 PMCID: PMC9748941 DOI: 10.3892/etm.2022.11710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 10/17/2022] [Indexed: 11/17/2022] Open
Abstract
Lipoblastoma is a rare benign mesenchymal neoplasm that typically occurs at various sites in infants and children but may also occur in adults. Thus, differential diagnoses are often performed. To understand this tumor type, the present study described clinicopathological features, diagnosis and differential diagnosis of different morphological lipoblastomas. A single-institution retrospective review of 36 lipoblastoma cases diagnosed between 2015 and 2021 was performed. Formalin-fixed paraffin-embedded tissue was used for S-100, CD34, P16 and desmin immunohistochemistry analysis, along with rapid fluorescence in situ hybridization (FISH) detection with pleiomorphic adenoma gene 1 (PLAG1). The 36 cases included 14 females and 22 males [age range, 7 days to 33 years (median, 16.5 years); 28 patients were aged ≤3 years] and the tumors were located in the trunk (n=16), limbs (n=12), head and neck (n=6), and perineum (n=2). Histologically, lipoblastomas were divided into classic (n=15), lipoma-like (n=13) and myxoid (n=8) subtypes. They comprised lobules of mature adipose tissue of varying size and a fine capillary network surrounded by mucinous stroma. Single- or multivesicular lipoblasts positive for S-100 (29/36, 81%) were observed, with occasional mature adipocytes. Peripheral vessels and cytoplasm of primitive mesenchymal cells were diffusely positive for CD34 (36/36, 100%), whereas primitive mesenchymal cells and striated muscle tissue were positive for desmin (26/36, 72%). Most tumor cells were negative while only few were positive for P16 (8/36, 22%). FISH revealed PLAG1 breakage and rearrangement in 24/32 (75%) patients. In total, 28 patients were followed up post-operatively (range, 2-84 months; median, 41 months; 3 patients relapsed and 8 were lost to follow-up). In conclusion, diagnosis of a typical lipoblastoma is not difficult and PLAG1 breakage detection is key for the diagnosis.
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Affiliation(s)
- Wenchuan Zhang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Shuwan Zhang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Zixin Yang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Ying Zhang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Zhe Wang
- Department of Pathology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China,Correspondence to: Professor Zhe Wang, Department of Pathology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Shenyang, Liaoning 110004, P.R. China
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16
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Ganzert C, Popov A, Lücke E, Franke S, Jechorek D, Zenker M, Walles T, Pech M, Schreiber J. Fatal course of a benign mediastinal lipoblastoma in a 20-year-old woman. Pathol Res Pract 2022; 239:154161. [DOI: 10.1016/j.prp.2022.154161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/01/2022] [Accepted: 10/06/2022] [Indexed: 10/31/2022]
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17
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Santisukwongchote S, Thorner PS, Desudchit T, Techavichit P, Jittapiromsak N, Amornfa J, Shuangshoti S, Shuangshoti S, Teerapakpinyo C. Pediatric fibromyxoid tumor with PLAG1 fusion: An emerging entity with a novel intracranial location. Neuropathology 2022; 42:315-322. [PMID: 35723650 DOI: 10.1111/neup.12837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 11/27/2022]
Abstract
Translocations involving PLAG1 occur in several tumors, most commonly pleomorphic adenoma and lipoblastoma. Recently, a distinctive soft tissue tumor with a PLAG1 fusion has been reported in the pediatric age group. These are low grade tumors with a fibroblastic or mixed fibroblastic and myxoid morphology but no other lines of differentiation. They are typically immunopositive for desmin and CD34. The partner genes for these tumors have included YWHAZ, EEF1A1, ZFHX4l, CHCHD7, and PCMTD1. We report another case of this fibromyxoid tumor with a PLAG1 fusion, this time with COL3A1 as the partner gene. The fusion placed expression of a full-length PLAG1 protein under the control of the constitutively active COL3A1 promoter. Overexpression of PLAG1 was confirmed by diffusely positive immunostaining for PLAG1. The most novel aspect of this tumor is the intracranial location. Opinion has been divided over whether these tumors are a specific entity, or related to lipoblastoma, since that tumor also typically occurs in soft tissue in the pediatric age group and shows many of the same gene fusions. However, lipoblastoma has never been reported in an intracranial location and, thus, our case provides compelling evidence that this fibromyxoid tumor is indeed a distinct entity.
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Affiliation(s)
- Sakun Santisukwongchote
- Department of Pathology, Faculty of Medicine, Chulalongkorn University and The King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Paul Scott Thorner
- Department of Pathology, Faculty of Medicine, Chulalongkorn University and The King Chulalongkorn Memorial Hospital, Bangkok, Thailand.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Tayard Desudchit
- Integrative and Innovative Hematology/Oncology Research Unit, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Piti Techavichit
- Integrative and Innovative Hematology/Oncology Research Unit, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Nutchawan Jittapiromsak
- Department of Radiology, Faculty of Medicine, Chulalongkorn University and The King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Jiraporn Amornfa
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Chulalongkorn University and The King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Somruetai Shuangshoti
- Institute of Pathology, Dept of Medical Services, Ministry of Public Health, Bangkok, Thailand
| | - Shanop Shuangshoti
- Department of Pathology, Faculty of Medicine, Chulalongkorn University and The King Chulalongkorn Memorial Hospital, Bangkok, Thailand.,Chulalongkorn GenePRO Center, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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18
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Update of Pediatric Lipomatous Lesions: A Clinicopathological, Immunohistochemical and Molecular Overview. J Clin Med 2022; 11:jcm11071938. [PMID: 35407546 PMCID: PMC8999862 DOI: 10.3390/jcm11071938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 03/25/2022] [Accepted: 03/30/2022] [Indexed: 01/27/2023] Open
Abstract
Lipomatous neoplasms are a rare entity in the pediatric population, comprising less than 10% of soft tissue tumors in the first two decades of life. Some characteristics of pediatric adipocytic tumors are analogous to their adult counterparts, some pediatric lipomatous lesions however harbor unique features. In recent years, there have been significant advances in the understanding of the pathogenesis and hence in the classification and treatment of pediatric adipocytic tumors. This literature-based article will provide a review of the presently known clinicopathological, immunohistochemical and molecular features of pediatric lipomatous lesions.
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19
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Warren M, Tiwari N, Sy S, Raca G, Schmidt RJ, Pawel B. PLAG1 Immunohistochemical Staining Is a Surrogate Marker for PLAG1 Fusions in Lipoblastomas. Pediatr Dev Pathol 2022; 25:134-140. [PMID: 34601996 DOI: 10.1177/10935266211043366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The hallmark of lipoblastoma is a PLAG1 fusion. PLAG1 protein overexpression has been reported in sporadic PLAG1-rearranged lipoblastomas. METHODS We evaluated the utility of PLAG1 immunohistochemical staining (IHC) in 34 pediatric lipomatous tumors, correlating the results with histology and conventional cytogenetics, FISH and/or next generation sequencing (NGS) results. RESULTS The study included 24 lipoblastomas, divided into 2 groups designated as "Lipoblastoma 1" with both lipoblastoma histology and PLAG1 rearrangement (n = 16) and "Lipoblastoma 2" with lipoblastoma histology but without PLAG1 cytogenetic rearrangement (n = 8), and 10 lipomas with neither lipoblastoma histology nor a PLAG1 rearrangement. Using the presence of a fusion as the "gold standard" for diagnosing lipoblastoma (Lipoblastoma 1), the sensitivity of PLAG1 IHC was 94%. Using histologic features alone (Lipoblastoma 1 + 2), the sensitivity was 96%. Specificity, as defined by the ability to distinguish lipoma from lipoblastoma, was 100%, as there were no false positives in the lipoma group. CONCLUSIONS Cytogenetics/molecular testing is expensive and may not be ideal for detecting PLAG1 fusions because PLAG1 fusions are often cytogenetically cryptic and NGS panels may not include all partner genes. PLAG1 IHC is an inexpensive surrogate marker of PLAG1 fusions and may be useful in distinguishing lipoblastomas from lipomas.
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Affiliation(s)
- Mikako Warren
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Nishant Tiwari
- Department of Pathology and Laboratory Medicine, Phoenix Children's Hospital, Phoenix, Arizona
| | - Sabrina Sy
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Gordana Raca
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Ryan J Schmidt
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Bruce Pawel
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
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20
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Brčić I, Igrec J, Halbwedl I, Viertler C, Liegl-Atzwanger B. Expanding the spectrum of PLAG1-rearranged lipoblastomas arising in patients over 45, with identification of novel fusion partners. Mod Pathol 2022; 35:283-285. [PMID: 34400796 PMCID: PMC8786657 DOI: 10.1038/s41379-021-00888-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/27/2021] [Accepted: 07/27/2021] [Indexed: 12/11/2022]
Affiliation(s)
- Iva Brčić
- grid.11598.340000 0000 8988 2476Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Jasminka Igrec
- grid.11598.340000 0000 8988 2476Division of General Radiology, Department of Radiology, Comprehensive Cancer Centre Graz, Medical University of Graz, Graz, Austria
| | - Iris Halbwedl
- grid.11598.340000 0000 8988 2476Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Christian Viertler
- grid.11598.340000 0000 8988 2476Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
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21
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Thway K. What’s new in adipocytic neoplasia? Histopathology 2021; 80:76-97. [DOI: 10.1111/his.14548] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 08/18/2021] [Accepted: 08/20/2021] [Indexed: 12/22/2022]
Affiliation(s)
- Khin Thway
- Sarcoma Unit Royal Marsden Hospital London UK
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22
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Gerhard-Hartmann E, Vokuhl C, Roth S, Steinmüller T, Rosenfeldt M, Zamò A, Rosenwald A, Appenzeller S, Ernestus K, Maurus K. The histological and molecular spectrum of lipoblastoma: A case series with identification of three novel gene fusions by targeted RNA-sequencing. Pathol Res Pract 2021; 226:153591. [PMID: 34455363 DOI: 10.1016/j.prp.2021.153591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 08/14/2021] [Indexed: 12/14/2022]
Abstract
Lipoblastoma is a rare benign mesenchymal neoplasm that typically occurs in infancy but may also occur in older age groups and various locations. Thus, there are often numerous clinical differential diagnoses. Moreover, lipoblastomas can show a broad histologic spectrum, which can hamper the correct diagnosis, particularly in small biopsies. At the genomic level, lipoblastomas are characterized by chromosomal fusions involving the PLAG1 gene. We investigated 11 lipoblastoma samples from 10 pediatric patients (age range five months to 12 years), including one patient with local recurrence, in view of their histopathological features, and performed targeted RNA sequencing. We found a broad histological spectrum with some tumors with prominent myxoid changes, but also tumors composed mainly of mature adipocytic cells, and classified the cases according to the literature as classic (mixed), maturing, or myxoid subtype. By targeted RNA sequencing analysis, we identified characteristic PLAG1 rearrangements in 70% of the investigated cases. Moreover, these analyses revealed three novel gene fusions, two affecting the PLAG1 gene and one involving HMGA2. Besides, we performed PLAG1 immunohistochemistry and identified positive cells, typically immature adipocytic cells and spindle cells, at various numbers in all cases. However, in the maturing areas, only very sparsely positive cells were found, limiting the value of the PLAG1 immunohistochemistry as an adjunct in the diagnosis of lipoblastoma, particularly for the maturing subtype and small biopsies. The presented case series confirms the broad morphological spectrum of lipoblastoma described in the literature and underlines the value of modern molecular diagnostic approaches as a supportive diagnostic tool in challenging cases and for gaining further insights into the molecular basis of this rare mesenchymal tumor.
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Affiliation(s)
- Elena Gerhard-Hartmann
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany.
| | - Christian Vokuhl
- Section of Pediatric Pathology, Department of Pathology, University Hospital Bonn, Bonn, Germany
| | - Sabine Roth
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Tabea Steinmüller
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Mathias Rosenfeldt
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Alberto Zamò
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Andreas Rosenwald
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Silke Appenzeller
- Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Karen Ernestus
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
| | - Katja Maurus
- Institute of Pathology, University of Würzburg, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Hospital of Würzburg, Würzburg, Germany
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23
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Chebib I, Taylor MS, Nardi V, Rivera MN, Lennerz JK, Cote GM, Choy E, Lozano Calderón SA, Raskin KA, Schwab JH, Mullen JT, Chen YLE, Hung YP, Nielsen GP, Deshpande V. Clinical Utility of Anchored Multiplex Solid Fusion Assay for Diagnosis of Bone and Soft Tissue Tumors. Am J Surg Pathol 2021; 45:1127-1137. [PMID: 34115673 DOI: 10.1097/pas.0000000000001745] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Sarcoma diagnosis has become increasingly complex, requiring a combination of morphology, immunohistochemistry, and molecular studies to derive specific diagnoses. We evaluated the role of anchored multiplex polymerase chain reaction-based gene fusion assay in sarcoma diagnostics. Between 2015 and 2018, bone and soft tissue sarcomas with fusion assay results were compared with the histologic diagnosis. Of 143 sarcomas tested for fusions, 43 (30%) had a detectable fusion. In review, they could be classified into 2 main categories: (1) 31 tumors with concordant morphologic and fusion data; and (2) 12 tumors where the fusion panel identified an unexpected rearrangement that played a significant role in classification. The overall concordance of the fusion assay results with morphology/immunohistochemistry or alternate confirmatory molecular studies was 83%. Collectively, anchored multiplex polymerase chain reaction-based solid fusion assay represents a robust means of detecting targeted fusions with known and novel partners. The predictive value of the panel is highest in tumors that show a monomorphic cell population, round cell tumors, as well as tumors rich in inflammatory cells. However, with an increased ability to discover fusions of uncertain significance, it remains essential to emphasize that the diagnosis of bone and soft tissue neoplasms requires the integration of morphology and immunohistochemical profile with these molecular methods, for accurate diagnosis and optimal clinical management of sarcomas.
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Affiliation(s)
| | | | | | | | | | - Gregory M Cote
- Department of Internal Medicine, Division of Hematology/Oncology
| | - Edwin Choy
- Department of Internal Medicine, Division of Hematology/Oncology
| | | | | | | | | | - Yen-Lin E Chen
- Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Yin P Hung
- James Homer Wright Pathology Laboratories
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24
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Thiryayi SA, Turashvili G, Latta EK, Swanson D, Zhang L, Antonescu CR, Dickson BC. PLAG1-rearrangment in a uterine leiomyosarcoma with myxoid stroma and heterologous differentiation. Genes Chromosomes Cancer 2021; 60:713-717. [PMID: 34184333 DOI: 10.1002/gcc.22980] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/12/2021] [Accepted: 06/16/2021] [Indexed: 01/22/2023] Open
Abstract
A variety of molecular alterations have been reported in uterine leiomyosarcomas, but most are considered nondiagnostic. There are, however, rare exceptions including PLAG1 rearrangement which has recently been identified in a subset of myxoid leiomyosarcomas. A 41-year-old woman presented with symptoms of a fibroid. She underwent a myomectomy which revealed a high-grade uterine sarcoma with areas of myxoid stroma and heterologous elements. The tumor expressed desmin, smooth muscle actin, H-caldesmon, and estrogen and progesterone receptors. RNA sequencing revealed a novel TRIM13-PLAG1 fusion gene which was subsequently independently confirmed by fluorescence in situ hybridization. On further evaluation the patient was found to have multiple pulmonary metastases and died due to disease progression shortly after diagnosis. This report describes a novel fusion partner of PLAG1 in a uterine leiomyosarcoma with myxoid leiomyosarcoma and heterologous elements, thereby broadening the spectrum of morphologic and genetic findings within this rare group of neoplasms.
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Affiliation(s)
- Sakinah A Thiryayi
- Department of Pathology & Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Gulisa Turashvili
- Department of Pathology & Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Eleanor K Latta
- Department of Laboratory Medicine, St. Michael's Hospital, Toronto, Ontario, Canada
| | - David Swanson
- Department of Pathology & Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Lei Zhang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Cristina R Antonescu
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Brendan C Dickson
- Department of Pathology & Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
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Giovannoni I, Barresi S, Rossi S, Stracuzzi A, Argentieri MG, Alaggio R. Pediatric lipoblastoma with a novel EEF1A1-PLAG1 fusion. Genes Chromosomes Cancer 2021; 60:525-526. [PMID: 33686712 DOI: 10.1002/gcc.22945] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 03/05/2021] [Indexed: 01/10/2023] Open
Affiliation(s)
- Isabella Giovannoni
- Pathology Unit, Department of Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sabina Barresi
- Pathology Unit, Department of Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sabrina Rossi
- Pathology Unit, Department of Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Alessandra Stracuzzi
- Pathology Unit, Department of Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Rita Alaggio
- Pathology Unit, Department of Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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26
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Killian K, Leckey BD, Naous R, McGough RL, Surrey LF, John I. Novel MEAF6-SUZ12 fusion in ossifying fibromyxoid tumor with unusual features. Genes Chromosomes Cancer 2021; 60:631-634. [PMID: 33840146 DOI: 10.1002/gcc.22951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 12/19/2022] Open
Abstract
Ossifying fibromyxoid tumor (OFMT) is a rare soft tissue neoplasm of uncertain differentiation that has the capacity for local recurrence and metastasis. Many OFMTs, including typical, atypical, and malignant tumors, have demonstrated recurrent gene fusions. The fusion partners reported to date share a common core function in that they play either a direct or indirect role in processes influencing histone modification. Herein, we report an OFMT with unusual morphology and non-specific immunoprofile harboring a novel MEAF6-SUZ12 fusion. A 34-year-old male presented with a slowly growing mass in the right antecubital fossa. Excision demonstrated a 6.9 cm partially encapsulated, tan-white, lobulated, and calcified lesion. Microscopic evaluation demonstrated cytologically bland spindle to ovoid cells arranged in a haphazard manner within a fibromyxoid background containing dense collagen, often with sclerotic nodules, and randomly distributed ossification. The tumor cells were diffusely positive for CD34 while essentially negative for S100, desmin, MUC4, SOX10, AE1/3, SMA, and EMA. Next-generation sequencing studies (sarcoma gene fusion next-generation sequencing panel with subsequent Sanger confirmation) performed on formalin-fixed paraffin-embedded tissue detected a fusion product between MEAF6 exon 4 (NM_001270875) and SUZ12 exon 2 (NM_001321207.1). The proposed mechanism of pathogenesis in OFMT, namely epigenetic dysregulation, is reinforced by the fact that both of these partner genes are involved in histone modification.
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Affiliation(s)
- Katherine Killian
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Bruce D Leckey
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Rana Naous
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Richard L McGough
- Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Lea F Surrey
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ivy John
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
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Chung CT, Antonescu CR, Dickson BC, Chami R, Marrano P, Fan R, Shago M, Hameed M, Thorner PS. Pediatric fibromyxoid soft tissue tumor with PLAG1 fusion: A novel entity? Genes Chromosomes Cancer 2021; 60:263-271. [PMID: 33300192 PMCID: PMC8358975 DOI: 10.1002/gcc.22926] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 02/06/2023] Open
Abstract
The classification of undifferentiated soft tissue tumors continues to evolve with the expanded application of molecular analysis in clinical practice. We report three cases of a unique soft tissue tumor in young children (5 months to 2 years old) displaying a purely fibromyxoid histology, with positive staining for desmin and CD34. In two cases, RNA sequencing detected a YWHAZ-PLAG1 gene fusion, while in the third case, a previously unreported EEF1A1-PLAG1 fusion was identified. PLAG1 fusions have been reported in several pathologic entities including pleomorphic adenoma, myoepithelial tumors of skin and soft tissue, and lipoblastoma, the latter occurring preferentially in young children. In these tumors, expression of a full length PLAG1 protein comes under the control of the constitutively active promoter of the partner gene in the fusion, and the current cases conform to that model. Overexpression of PLAG1 was confirmed by diffusely positive immunostaining for PLAG1 in all three cases. Our findings raise the possibility of a novel fibromyxoid neoplasm in childhood associated with these rare PLAG1 fusion variants. The only other report of a PLAG1-YWHAZ fusion occurred in a pediatric tumor diagnosed as a "fibroblastic lipoblastoma." This finding raises the possibility of a relationship with our three cases, even though our cases lacked any fat component. Further studies with regard to a shared pathogenesis are required.
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Affiliation(s)
- Catherine T. Chung
- Division of Pathology, The Hospital for Sick Children, Toronto, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | | | - Brendan C. Dickson
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Canada
| | - Rose Chami
- Division of Pathology, The Hospital for Sick Children, Toronto, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Paula Marrano
- Division of Pathology, The Hospital for Sick Children, Toronto, Canada
| | - Rong Fan
- Division of Pediatric Pathology, Riley Hospital for Children at Indiana University Health, Indianapolis, Indiana
| | - Mary Shago
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- Division of Genome Diagnostics, Department of Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Meera Hameed
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Paul S. Thorner
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
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28
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Chiang S. Recent advances in smooth muscle tumors with PGR and PLAG1 gene fusions and myofibroblastic uterine neoplasms. Genes Chromosomes Cancer 2020; 60:138-146. [PMID: 33230916 DOI: 10.1002/gcc.22920] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 11/12/2020] [Indexed: 12/11/2022] Open
Abstract
Uterine epithelioid and myxoid leiomyosarcomas and inflammatory myofibroblastic tumors are rare mesenchymal neoplasms. Next-generation sequencing recently detected novel PGR fusions in uterine epithelioid leiomyosarcomas that demonstrate characteristic rhabdoid and spindled morphology. PLAG1 gene fusions have also been identified in a subset of myxoid leiomyosarcomas and are associated with PLAG1 overexpression. ALK rearrangements underpin the vast majority of uterine inflammatory myofibroblastic tumors, which demonstrate morphologic, and immunohistochemical features similar to those of inflammatory myofibroblastic tumors elsewhere. This review summarizes the morphologic, immunophenotypic, and molecular genetic features of PGR fusion-positive epithelioid leiomyosarcoma, PLAG1 fusion-positive myxoid leiomyosarcoma, and inflammatory myofibroblastic tumors of the uterus.
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Affiliation(s)
- Sarah Chiang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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