Objective: To investigate the clinicopathological and cytogenetic features of cryptic COL1A1-PDGFB fusion dermatofibrosarcoma protuberans (CC-DFSP). Methods: Three cases of CC-DFSP diagnosed in West China Hospital, Sichuan University, Chengdu, China from January 2021 to September 2021 were studied. Immunohistochemistry for CD34 and other markers, fluorescence in situ hybridization (FISH) for PDGFB, COL1A1-PDGFB and COL1A1, next-generation sequencing (NGS), reverse-transcriptase polymerase chain reaction (RT-PCR) and Sanger sequencing were performed. Results: There were three cases of CC-DFSP, including two females and one male. The patients were 29, 44 and 32 years old, respectively. The sites were abdominal wall, caruncle and scapula. Microscopically, they were poorly circumscribed. The spindle cells of the tumors infiltrated into the whole dermis or subcutaneous tissues, typically arranging in a storiform pattern. Immunohistochemically, the neoplastic cells exhibited diffuse CD34 expression, but were negative for S-100, SMA, and Myogenin. Loss of H3K27me3 was not observed in the tumor cells. The Ki-67 index was 10%-15%. The 3 cases were all negative for PDGFB rearrangement and COL1A1-PDGFB fusion, whereas showing unbalanced rearrangement for COL1A1. Case 1 showed a COL1A1 (exon 31)-PDGFB (exon 2) fusion using NGS, which was further validated through RT-PCR and Sanger sequencing. All patients underwent extended surgical resection. Except for case 3 with recurrence 2 years after surgical resection, the other 2 cases showed no recurrence or metastasis during the follow-up. Conclusions: FISH has shown its validity for detecting PDGFB rearrangement and COL1A1-PDGFB fusion and widely applied in clinical detection. However, for cases with negative routine FISH screening that were highly suspicious for DFSPs, supplementary NGS or at least COL1A1 break-apart FISH screening could be helpful to identify cryptic COL1A1-PDGFB fusions or other variant fusions.
Female ; Humans ; Male ; Collagen Type I, alpha 1 Chain ; Dermatofibrosarcoma/pathology* ; In Situ Hybridization, Fluorescence ; Oncogene Proteins, Fusion/genetics* ; Proto-Oncogene Proteins c-sis/genetics* ; Skin Neoplasms/pathology* ; Adult

Humans ; Child ; Dermatofibrosarcoma/surgery* ; Skin Neoplasms/surgery* ; Oncogene Proteins, Fusion/genetics*

Humans ; Fibrosarcoma/surgery* ; Sarcoma ; Temporal Bone ; Soft Tissue Neoplasms/surgery*

Malignant peripheral nerve sheath tumor (MPNST) is a rare neurogenic malignant tumor. MPNST has aty-pical clinical symptoms and imaging presentations, difficult diagnosis, a high degree of malignancy, and poor prognosis. It usually occurs in the trunk, approximately 20% in the head and neck, and rarely in the mouth. This paper reports a case of MPNST of the tongue. A summary of the clinical features, diagnosis, and treatment of MPNST is presented in combination with a literature review to provide a reference for the diagnosis and treatment of this disease.
Humans ; Nerve Sheath Neoplasms/pathology* ; Neurofibrosarcoma ; Tongue/pathology*

Objective:To analyze the diagnosis, treatment and prognosis of patients with rare malignant tumors of the temporal bone. Methods:Four cases of rare temporal bone malignant tumors in our hospital between March 2014 and December 2020 were reviewed, including two cases of chondrosarcoma, one case of fibrosarcoma and one case of endolymphatic cystic papillary adenocarcinoma. There were three males and one female, ages between 28 and 56 years at the time of surgery. Common symptoms included hearing loss, facioplegia, tinnitus, and headache. All patients underwent imaging examinations to evaluate the extent of the lesions. Tumors were removed by subtotal temporal bone resection or infratemporal fossa approach, and postoperative adjuvant radiotherapy was applied if necessary. Results:One of the two chondrosarcoma patients was cured by complete resection of the tumor for 75 months, the other one recurred after the first excision of the tumor and underwent infratemporal fossa approach resection of skull base mass again with no recurrence found yet for 112 months. One patient with fibrosarcoma survived for 28 months after surgery with a positive margin and post-operative radiotherapy. One patient with endolymphatic cystic papillary adenocarcinoma recurred 12 months after subtotal lithotomy, and underwent subtotal temporal bone resection again, combined with radiotherapy. No recurrence was found for 63 months. Conclusion:The incidence of rare temporal bone malignant tumors is extremely low, the location is hidden, and the symptoms are atypical. Attention should be paid for early detection and early treatment. Surgical resection is the main treatment, and radiotherapy can be supplemented in the advanced stage or with a positive margin.
Adult ; Female ; Humans ; Male ; Middle Aged ; Chondrosarcoma/surgery* ; Fibrosarcoma ; Neoplasm Recurrence, Local ; Retrospective Studies ; Skull Base/surgery* ; Skull Base Neoplasms/surgery* ; Temporal Bone/pathology* ; Treatment Outcome

Humans ; Solitary Fibrous Tumors/pathology* ; Osteosarcoma/pathology* ; Fibrosarcoma ; Bone Neoplasms/surgery*

Objective: To investigate the clinicopathological, immunophenotypic, and genetic features of malignant peripheral nerve sheath tumor (MPNST). Methods: Twenty-three cases of MPNST were diagnosed at the Jiangsu Province Hospital (the First Affiliated Hospital of Nanjing Medical University), China, between January 2012 and December 2022 and thus included in the study. EnVision immunostaining and next-generation sequencing (NGS) were used to examine their immunophenotypical characteristics and genomic aberrations, respectively. Results: There were 10 males and 13 females, with an age range of 11 to 79 years (median 36 years), including 14 cases of neurofibromatosis type I-associated MPNST and 9 cases of sporadic MPNST. The tumors were located in extremities (7 cases), trunk (4 cases), neck and shoulder (3 cases), chest cavity (3 cases), paraspinal area (2 cases), abdominal cavity (2 cases), retroperitoneum (1 case), and pelvic cavity (1 case). Morphologically, the tumors were composed of dense spindle cells arranged in fascicles. Periphery neurofibroma-like pattern was found in 73.9% (17/23) of the cases. Under low magnification, alternating hypercellular and hypocellular areas resembled marbled appearance. Under high power, the tumor cell nuclei were irregular, presenting with oval, conical, comma-like, bullet-like or wavy contour. In 7 cases, the tumor cells demonstrated marked cytological pleomorphism and rare giant tumor cells. The mitotic figures were commonly not less than 3/10 HPF, and geographic necrosis was often noted. Immunohistochemically, tumor cells were positive for S-100 (14/23, 60.9%) and SOX10 (11/23, 47.8%). The loss of the CD34-positive fibroblastic network encountered in neurofibromas was observed in 14/17 of the MPNST cases. The loss of H3K27me3 expression was observed in 82.6% (19/23) of the cases. Moreover, SDHA and SDHB losses were presented in one case. NGS revealed that NF1 gene loss of function (germline or somatic) were found in all 5 cases tested. Furthermore, four cases accompanied with somatic mutations of SUZ12 gene and half of them had somatic mutations of TP53 gene, while one case with germline mutation in SDHA gene and somatic mutations in FAT1, BRAF, and KRAS genes. Available clinical follow-up was obtained in 19 cases and ranged from 1 to 67 months. Four patients died of the disease, all of whom had the clinical history of neurofibromatosis type Ⅰ. Conclusions: MPNST is difficult to be differentiated from a variety of spindle cell tumors due to its wide spectrum of histological morphology and complex genetic changes. H3K27me3 is a useful diagnostic marker, while the loss of CD34 positive fibroblastic network can also be a diagnostic feature of MPNST. NF1 gene inactivation mutations and complete loss of PRC2 activity are the common molecular diagnostic features, but other less commonly recurred genomic aberrations might also contribute to the MPNST pathogenesis.
Female ; Male ; Humans ; Child ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Neurofibrosarcoma ; Neurofibromatosis 1 ; Histones ; Genes, p53 ; Nerve Sheath Neoplasms

Dermatofibrosarcoma ; Fibroma ; Humans ; Skin Neoplasms

Humans ; Neurofibrosarcoma ; Adrenal Glands

Fibrosarcoma/surgery* ; Humans ; Infant, Newborn ; Lung Neoplasms ; Neck