Fusion of Platelet Derived Growth Factor Receptor Alpha () With Ubiquitin Specific Peptidase 8 () in a Calcified Chondroid Mesenchymal Neoplasm Harboring t(4;15)(q12;q21) as a Sole Aberration.

Background/aim: The term "calcified chondroid mesenchymal neoplasm" was introduced in 2021 to describe a group of tumors characterized by various morphological features, including the formation of cartilage or chondroid matrix. These tumors frequently carry chimeric genes where the 5'-end partner gene is fibronectin 1 and the 3'-end partner gene codes for receptor tyrosine kinase. Our study explores fusion of the genes platelet-derived growth factor receptor alpha (PDGFRA) and ubiquitin-specific peptidase 8 (USP8) in calcified chondroid mesenchymal neoplasm.

Fusion of the Genes for Interferon Regulatory Factor 2 Binding Protein 2 () and Caudal Type Homeobox 1 () in a Chondrogenic Tumor.

Background/aim: Chondrogenic tumors are benign, intermediate or malignant neoplasms showing cartilaginous differentiation. In 2012, we reported a mesenchymal chondrosarcoma carrying a t(1;5)(q42;q32) leading to an IRF2BP2::CDX1 fusion gene. Here, we report a second chondrogenic tumor carrying an IRF2BP2::CDX1 chimera.

Pathogenetic Dichotomy in Angioleiomyoma.

Background/aim: Angioleiomyoma is a benign tumor, occurs at any age, and arises most frequently in the lower extremities. Genetic information on angioleiomyomas is restricted to six reported abnormal karyotypes, losses in chromosome 22 and gains in Xq found by comparative genomic hybridization, and mutation analysis of notch receptor 2 (NOTCH2), NOTCH3, platelet-derived growth factor receptor beta (PDGFRB), and mediator complex subunit 12 (MED12) in a few tumors. Herein, we report the genetic findings in another three angioleiomyomas.

Fusion of the High-mobility Group AT-Hook 2 () and the Gelsolin () Genes in Lipomas With t(9;12)(q33;q14) Chromosomal Translocation.

Background/aim: Lipomas are benign tumors composed of mature fat cells. They are common soft tissue tumors that often carry chromosome aberrations involving 12q14 resulting in rearrangements, deregulation, and generation of chimeras of the high-mobility group AT-hook 2 gene (HMGA2) which maps in 12q14.3.

Recurrent 8q11-13 Aberrations Leading to Rearrangements, Including Novel Chimeras and , in Lipomatous Tumors.

Background/aim: Structural abnormalities of chromosome bands 8q11-13, resulting in rearrangement of the pleomorphic adenoma gene 1 (PLAG1), are known to characterize lipoblastoma, a benign fat cell tumor, found mainly in children. Here, we describe 8q11-13 rearrangements and their molecular consequences on PLAG1 in 7 lipomatous tumors in adults.

Materials And Methods: The patients were 5 males and 2 females between 23 and 62 years old.

Genomic Complexity as a Biomarker to De-Escalate Adjuvant Imatinib Treatment in High-Risk Gastrointestinal Stromal Tumor.

Purpose: Adjuvant imatinib treatment is recommended for patients with localized gastrointestinal stromal tumor (GIST) at high risk of recurrence. Almost half of high-risk patients are cured by surgery alone, indicating a need for improved selection of patients for adjuvant therapy. The aim of this study was to investigate if genomic tumor complexity could be used as a prognostic biomarker.

Chromosome Translocation t(10;19)(q26;q13) in a CIC-sarcoma.

Background/aim: CIC-sarcomas are characterized by rearrangements of the capicua transcriptional repressor (CIC) gene on chromosome subband 19q13.2, generating chimeras in which CIC is the 5'-end partner. Most reported CIC-sarcomas have been detected using PCR amplifications together with Sanger sequencing, high throughput sequencing, and fluorescence in situ hybridization (FISH).

Fusion of the and Genes in Uterine Leiomyoma With t(9;12)(p22;q14).

Background/aim: The translocation t(9;12) (p22;q14~15) has been reported in lipomas, pleomorphic adenomas, a myolipoma, two chondroid hamartomas, and two uterine leiomyomas. In lipomas and pleomorphic adenomas, the translocation fuses HMGA2 (12q14) with the NFIB gene from 9p22; in myolipoma, it fuses HMGA2 with C9orf92 from 9p22; and in chondroid hamartomas, fluorescence in situ hybridization (FISH) investigations showed the chromosomal aberration to cause intragenic rearrangement of HMGA2. The translocation's molecular consequence in a uterine leiomyoma is described here.

A Novel Cryptic t(2;3)(p21;q25) Translocation Fuses the and Genes in Uterine Leiomyoma With 3q- as the Sole Visible Chromosome Abnormality.

Background/aim: Deletions in the q arm of chromosome 3 have been reported in uterine leiomyomas, also as sole anomalies. Because some neoplasia-associated deletions may give rise to tumorigenic fusion genes, we chose to investigate thoroughly one such tumor.

Materials And Methods: A uterine leiomyoma obtained from a 45-year-old woman had the karyotype 46,XX,del(3)(q?)[11].

Fusion of High Mobility Group AT-hook 2 Gene () With the Chromosome 12 Open Reading Frame 42 Gene () in an Aggressive Angiomyxoma With del(12)(q14q23) as the Sole Cytogenetic Anomaly.

Background/aim: Aggressive angiomyxomas are mostly found in the pelvic and perineal region and are prone to recur after surgery. Cytogenetic information is available on only nine such tumors. Herein, we report the cytogenetic anomaly and its molecular consequence in another aggressive angiomyxoma.

Presence of a t(12;18)(q14;q21) Chromosome Translocation and Fusion of the Genes for High-mobility Group AT-Hook 2 () and WNT Inhibitory Factor 1 () in Infrapatellar Fat Pad Cells from a Patient With Hoffa's Disease.

Background/aim: Hoffa's disease is anterior knee pain presumably stemming from inflammatory fibrous hyperplasia of the infrapatellar fat pad (Hoffa's pad). The etiology and pathogenesis are unclear, however, and no genetic information about the disease has been published. We report the genetic findings in cells from the fat pad of a patient with Hoffa's disease.

Chromosomal Translocation t(5;12)(p13;q14) Leading to Fusion of High-mobility Group AT-hook 2 Gene With Intergenic Sequences From Chromosome Sub-Band 5p13.2 in Benign Myoid Neoplasms of the Breast: A Second Case.

Background/aim: Recently, we reported a myoid hamartoma carrying a t(5;12)(p13;q14) karyotypic aberration leading to fusion of the high-mobility group AT-hook 2 (HMGA2) gene with a sequence from chromosome sub-band 5p13.2. We describe here another benign myoid tumor of the breast with identical genetic aberrations.

Cytogenetic and molecular analyses of 291 gastrointestinal stromal tumors: site-specific cytogenetic evolution as evidence of pathogenetic heterogeneity.

Gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm with variable behavior. An increased understanding of the tumor pathogenesis may improve clinical decision-making. Our aim was to obtain more data about the overall chromosome aberrations and intratumor cytogenetic heterogeneity in GIST.

Recurrent Fusion of the Genes for High-mobility Group AT-hook 2 () and Nuclear Receptor Co-repressor 2 () in Osteoclastic Giant Cell-rich Tumors of Bone.

Background/aim: Chimeras involving the high-mobility group AT-hook 2 gene (HMGA2 in 12q14.3) have been found in lipomas and other benign mesenchymal tumors. We report here a fusion of HMGA2 with the nuclear receptor co-repressor 2 gene (NCOR2 in 12q24.

Several Fusion Genes Identified in a Spermatic Cord Leiomyoma With Rearrangements of Chromosome Arms 3p and 21q.

Background/aim: Benign smooth-muscle tumors, leiomyomas, occur in nearly every organ but are most common in the uterus. Whereas much is known about the genetics of uterine leiomyomas, little genetic information exists about leiomyomas of other organs. Here, we report and discuss the genetic findings in a para-testicular leiomyoma.

Cytogenetic and Molecular Study of an Adult Sclerosing Rhabdomyosarcoma of the Extremity: -mutation and Clonal Evolution.

Background: Spindle cell/sclerosing rhabdomyosarcoma is a genomically heterogeneous, uncommon subtype of rhabdomyosarcoma, particularly rare in adults. Its MYOD1-mutant variant is aggressive irrespective of age. Cytogenetic data on spindle cell/sclerosing rhabdomyosarcoma are sparse and disparate.

Fusion of the Lumican () Gene With the Ubiquitin Specific Peptidase 6 () Gene in an Aneurysmal Bone Cyst Carrying a t(12;17)(q21;p13) Chromosome Translocation.

Background/aim: Aneurysmal bone cyst is a benign bone lesion with a strong tendency to recur. The rearrangement of chromosome band 17p13/USP6 gene is now considered a characteristic genetic feature of aneurysmal bone cyst, with t(16;17)(q22;p13)/CDH11-USP6 as the most frequent chromosomal aberration/fusion gene. We report a novel variant translocation leading to a new fusion gene in an aneurysmal bone cyst.

Recurrent Fusion of the GRB2 Associated Binding Protein 1 () Gene With ABL Proto-oncogene 1 () in Benign Pediatric Soft Tissue Tumors.

Background/aim: Fusions of the ABL proto-oncogene 1 gene (ABL1 in 9q34) are common in leukemias but rare in solid tumors. The most notable is the t(9;22)(q34;q11)/BCR-ABL1 coding for a chimeric tyrosine kinase. We herein report an ABL1-fusion in a pediatric tumor.

Fusion of the Gene With in a Hemangioma Carrying a t(X;15)(q22;q26) Chromosomal Translocation.

Background/aim: Hemangiomas are benign neoplastic proliferations of blood vessels. Cytogenetic information on hemangiomas is limited to four tumors with abnormal karyotypes. We report here a solitary chromosomal translocation and its molecular consequence in a hemangioma.

and Fusion Genes in Chondroid Syringoma.

Background/aim: Chondroid syringoma is a rare benign tumor emanating from sweat glands. Although rearrangements of the pleomorphic adenoma gene 1 (PLAG1) have been reported in such tumors, information on PLAG1 fusion genes is very limited.

Materials And Methods: Cytogenetic, fluorescence in situ hybridization, RNA sequencing, array comparative genomic hybridization, reverse transcription polymerase chain reaction, and Sanger sequencing analyses were performed on two chondroid syringoma cases.

An Unbalanced Chromosome Translocation Between 7p22 and 12q13 Leads to Fusion in Pericytoma.

Background/aim: Since the first description of five pericytomas with the t(7;12)/ACTB-GLI1 fusion gene, only three new tumors were studied by both cytogenetics and molecular techniques. We report here genetic data on another case of this rare tumor.

Materials And Methods: Cytogenetic, fluorescence in situ hybridization (FISH), reverse transcription polymerase chain reaction (RT-PCR), and Sanger sequencing analyses were performed.

and Fusion Genes in Osteoblastoma.

Background/aim: Osteoblastoma is a rare benign tumor of the bones in which recurrent rearrangements of FOS have been found. Our aim was to investigate two osteoblastomas for possible genetic aberrations.

Materials And Methods: Cytogenetic, RNA sequencing, and molecular analyses were performed.