[Intestinal calcifying fibrous tumor: case report]. / Tumor fibroso calcificante intestinal: reporte de caso.

Calcifying fibrous tumor (CFT) is a rare benign lesion of mesenchymal origin that may present similar characteristics to other more common tumors. We present the case of a 36-year-old woman with a tumor in the proximal jejunum, initially suspected to be a gastrointestinal stromal tumor (GIST). Surgical resection was performed, revealing a well-demarcated nodule at the anti-mesenteric border with microscopic features typical of a calcifying fibrous tumor. The tumor cells were positive for CD34 and negative for other markers, differentiating it from other neoplasms. Calcifying fibrous tumors can be confused with more common tumors because of its appearance, but an accurate diagnosis supported by immunohistochemistry is essential. Complete surgical excision is usually curative.

Case of recurrent superficial CD34-positive fibroblastic tumor.

Superficial CD34-positive fibroblastic tumor (SCPFT) is a recently described rare superficial mesenchymal tumor. SCPFT has a distinctive morphologic appearance, marked by significant nuclear pleomorphism, low mitotic rate, and diffuse CD34 positivity. SCPFT is underdiagnosed because of its rarity and misdiagnosis as sarcoma, with very few reported cases of local recurrence or metastasis. Recognition and awareness of SCPFT are essential for accurate diagnosis and appropriate clinical management. We describe here the case of a 37-year-old male who presented with a right calf mass diagnosed as SCPFT with subsequent local recurrence of the tumor.

Superficial CD34 Positive Fibroblastic Tumour with Myxoid Stroma.

Superficial CD34 positive fibroblastic tumor is a rare low-grade neoplasm of the skin and subcutis with indolent behavior. This entity has been included in the current World Health Organisation (WHO) classification of soft tissue tumors. Pathological diagnosis can be challenging due to significant morphological overlap with other entities and the large spectrum of CD34 positive tumors. We report a case in a twenty-five male which showed characteristic diagnostic features, but in addition showed myxoid stroma. The presence of myxoid stroma has not been previously emphasized in this entity and broadens the histologic differential diagnosis significantly to include myxoid soft tissue tumors. A subset of these tumors harbor PRDM10-rearrangements, but a defining molecular feature has not yet been described, highlighting the need for further molecular characterization of this potentially genetically heterogenous tumor. Awareness of this entity among surgeons and pathologists is important to prevent misclassification as an aggressive sarcoma and avoid over-treatment.

[Fibrous hamartoma of infancy: a clinicopathological and molecular genetic analysis of 33 cases].

Objective: To investigate the clinicopathological features, immunophenotypic and molecular genetic characteristics and differential diagnosis of fibrous hamartoma of infancy (FHI). Methods: Thirty-three cases of surgically removed FHI were collected from the Department of Pathology, Henan Provincial People's Hospital from October 2011 to December 2020, the clinical and pathologic data with follow-up were collected and analyzed. Next-generation sequencing (NGS) and quantitative real time polymerase chain reaction (q-PCR) were used to study the molecular genetics. Results: The FHI cases occurred in 21 males and 12 females (mean age 16.7 months, range 6 months to 6 years). The sites included trunk (n=21), limb (n=11), and neck (n=1). All patients had painless solitary superficial soft tissue masses, the size was 1.5-9.0 cm (mean 3.8 cm). Microscopically, they were composed of mature adipose tissue, fibroblast/myofibroblast bundle and primitive mesenchymal cells in different proportions; giant cell fibroblastoma-like areas were seen in 14 cases. Immunohistochemistry showed variable expression of EGFR in the spindle cells and primitive mesenchymal components. In most cases, the spindle cells were positive for CD34 and SMA; giant cell fibroblastoma-like areas were strongly positive for CD34; and S-100 protein was expressed by adipocytes in all cases. Ki-67 labeling index ranged 1%-5%. There were recurrent somatic EGFR exon 20 insertion/duplication mutations in six cases tested by NGS, and there were three different mutation types: p.Asn771_His773dupAsnProHis, p.Pro772_His773insProProHis, and p.His773_Val774insThrHis. All the above 6 and another 15 tested cases showed EGFR exon 20 insertion/duplication mutations by q-PCR. Conclusions: FHI is a rare benign fibroblast/myofibroblast tumor. The characteristic histologic feature is organoid triphasic morphology, and the molecular feature is somatic mutation of EGFR exon 20 (insertion/duplication).

Superficial CD34-Positive Fibroblastic Tumor.

Superficial CD34-positive fibroblastic tumor (SCPFT) is a recently described entity that, despite significant pleomorphism, carries a good prognosis. We briefly describe this tumor and its principal differential diagnoses. Recognition of SCPFTs, including the clinical context in which they arise, is important to avoid confusion with other pleomorphic soft tissue tumors, particularly neoplasms in the group of pleomorphic sarcomas, which are typically aggressive tumors that could lead to unnecessary overtreatment.

A novel TJP1-ROS1 fusion in malignant peripheral nerve sheath tumor responding to crizotinib: A case report.

RATIONALE: Malignant peripheral nerve sheath tumor (MPNST) is a rare sarcoma. Owing to the lack of specific histological criteria, immunohistochemical, and molecular diagnostic markers, several differential diagnoses must be considered. Advances in molecular testing can provide significant insights for management of rare tumor. PATIENT CONCERNS: The patient was a 50-year-old man with a history of lumpectomy on the right back 30 years ago. He felt a stabbing pain at the right iliac fossa and went to the local hospital. DIAGNOSIS: By immunohistochemistry, the tumor cells stained positively for S-100 (focal +), CD34 (strong +++) and Ki-67 (20%), and negatively for smooth muscle actin, pan-cytokeratin, neurofilament, pan-cytokeratin-L, GFAP, CD31, STAT6, ERG, myogenin, and MyoD1. Combined with the histopathology and immunohistochemistry results, our initial diagnosis was solitary fibrous tumor (SFT) or MPNST. The tissue biopsy was sent for next-generation sequencing. neurofibromatosis type 1 Q1395Hfs*22 somatic mutation, neurofibromatosis type 1 D483Tfs*15 germline mutation, and amplifications of BTK, MDM2, ATF1, BMPR1A, EBHA2, GNA13, PTPN11, RAD52, RPTOR, and SOX9, as well as TJP1-ROS1 fusion, CDKN2A-IL1RAPL2 fusion and CDKN2A/UBAP1 rearrangement were identified. Given that NAB2-STAT6 fusion, a specific biomarker of SFT, was not identified in our patient's tumor, the SFT was excluded by through genetic testing results. Therefore, our finally diagnosis was a MPNST by 2 or more pathologists. INTERVENTIONS AND OUTCOMES: Subsequently, the patient received crizotinib therapy for 2 months and showed stable disease. However, after crizotinib continued treatment for 4 months, the patient's disease progressed. Soon after, the patient stopped crizotinib treatment and died in home. LESSONS: To our knowledge, this is the first report of the TJP1-ROS1 fusion, which expands the list of gene fusions and highlights new targets for targeted therapy. Also, our case underlines the value of multi-gene panel next-generation sequencing for diagnosis of MPNST.

Clinicopathologic Study of Calcifying Fibrous Tumor Emphasizing Different Anatomical Distribution and Favorable Prognosis.

AIMS: Calcifying fibrous tumor (CFT) is a very rare begin fibroblastic tumor featuring a widely anatomical distribution and may mimic various spindle cell tumors. Misdiagnosis and hence mistreatment are likely caused due to unfamiliarity to clinicians or junior pathologists. We collected a relatively large series of CFTs in our institution aiming at further summarizing their clinicopathologic features in Chinese patients and discussing the diagnosis and differential diagnosis in clinical practice. METHODS: Clinicopathologic data of 22 CFTs were retrospectively reviewed. Histologic features were reevaluated and summarized. Immunostaining markers include CD34, SMA, Desmin, keratin, S100, ALK1, CD117, IgG, IgG4, and Ki-67. Follow-up of all cases was performed. RESULTS: 22 CFTs include gastric (n=8), pulmonary (n=2), hepatic (n=2), cervical (n=1), appendiceal (n=1), esophageal (n=1), retroperitoneal (n=1), intra-abdominal (n=1), diaphragmatic (n=1), spermatic cord and scrotum (n=1), anconeal (n=1), mesenteric (n=1), and omental (n=1) lesions. Coexisting hepatocellular carcinoma, pancreatic carcinoma, pheochromocytoma, Castleman disease, and leiomyoma of the uterus and other metabolic or functional disorders were also appreciated. CFT histologically features spindle cells embedded dense hyalinized stroma with scattered psammomatous calcifications and lymphoplasmacytic infiltration and immunohistochemically for CD34. None of any individuals die of CFT per se. CONCLUSION: Our study discloses that CFT is a bona fide benign fibroblastic lesion, regardless of its developing location. Involvement of digestive tract seems much more common in the Chinese population. Awareness of the clinicopathologic characteristics of this rare entity and its mimickers contribute to avoiding misdiagnosis and mistreatment in clinical practice.

Atypical Fibroxanthoma.

Atypical fibroxanthoma (AFX) is a dermal spindle-cell sarcoma that is considered a superficial and clinically benign presentation of pleomorphic dermal sarcoma, malignant fibrous histiocytoma, and undifferentiated pleomorphic sarcoma. AFX appears clinically as a discrete red or pink nodule or papule, most commonly on the head and neck region of sun-damaged elderly patients. Histologic findings on routine hematoxylin and eosin staining reveal spindle-shaped, large, and pleomorphic tumor cells throughout the dermis. Immunohistochemistry is not specific for AFX, and the diagnosis is generally one of exclusion. AFX is best treated by complete surgical excision, with Mohs micrographic surgery considered the treatment of choice. Metastasis rarely occurs, but there is a high rate of local recurrence, especially in patients who are immunosuppressed.

Calcifying fibrous tumor of the terminal ileum mesentery: Case report.

RATIONALE: Calcifying fibrous tumors ("CFT") are recognized as extremely rare mesenchymal tumors with benign biological behavior and low rates of recurrence are seen after removal. The first case of a CFT was reported in 1988 as a possibly inflammatory triggered pseudotumor in deep soft tissue of children. Histologically, the tumor is typically composed of dense hyalinized collagen with paucicellular infiltration of lymphocytes and fibroblasts as well as psammomatous or dystrophic calcifications. It can affect soft tissue in very different anatomical locations, also intrathoracic and intra-abdominal, mimicking various different diagnoses. The etiology is understood to be unclear. Asymptomatic CFTs can be found incidentally on medical images. PATIENT CONCERNS: We present the case of a calcifying tumorous lesion found incidentally in the mesentery of the terminal ileum of a 34-year-old male patient in February 2016 undergoing a computed tomography for a urinary tract infection. DIAGNOSIS: Histopathological and immunhistochemical examination after surgery revealed a CFT. INTERVENTIONS: Our patient underwent lower abdominal median laparotomy for tumorectomy. OUTCOMES: Two years after surgery the patient is free of a recurrence. LESSIONS: We add another case of intra-abdominal CFT to medical literature to provide more information about this very seldom tumor. While the etiology of CFT should be further investigated, diagnosis and therapy seem clarified. CFT should be kept in mind as a rare differential diagnosis of calcifying tumors also in the abdominal cavity. Immunohistological work-up is important for finding the diagnosis and may also help solving pathogenetical questions.

Paratesticular Fibrous Pseudotumor: A New Entity of IgG4-Related Disease?

INTRODUCTION: Paratesticular fibrous pseudotumor (PFP) represents a benign tumor-like lesion confined to intrascrotal, paratesticular areas. Due to its rarity, only less than 200 cases have been reported to date, of which both pathogenesis and clinical management are little understood. Recently, PFP has been postulated to be among the spectrum of so-called immunoglobulin G4-related diseases (IgG4-RD). Here we describe a case of PFP focusing on the clinical, morphological features and the utility of immunohistochemistry to support the theory that PFP might be a potential member of IgG4-RD family. CASE PRESENTATION: A 41-year-old man presented with a slowly growing, right intrascrotal mass An MRI scan revealed a diffuse-proliferative nodular mass around the paratesticular area. The patient underwent right orchiectomy and a diffuse multinodular tumor with testicular compression was discovered without intratesticular infiltration. Postoperatively, the patient has been well for 2 years up to the recent follow up. On histological examination, the lesion consisted of hyalinized fibrotic tissue with storiform patterns. There were scattered germinal centers; lymphocytic vasculitis was also noted. The immunoglobulin G4 staining showed infiltration of positive plasma cells with highest count 52 per high-power field, whereas the mixed Kappa and Lambda immunoglobulin light chain expression indicated the polyclonality of the plasma cell population. CONCLUSIONS: The morphological and immunohistochemical features in our case support the theory of PFP being part of IgG4-RD. Familiarity to this tumor-like lesion is crucial, since it may respond to corticosteroid therapy, which may save patients from more aggressive surgical procedures.

Large-sized pedunculated and polypoidal angiomyofibroblastoma of the vulva: A case report and literature review.

Angiomyofibroblastoma (AMF) represents a rare, benign mesenchymal tumor with a predilection for the vulvovaginal region, which may be misdiagnosed as aggressive angiomyxoma (AAM). Herein, we report a case of a 20-year-old nulliparous Chinese woman with a unique pedunculated and polypoidal mass, which had been developing within the previous 6 months in the left labium majus, exhibiting the AAM clinical impression but diagnosed as AMF. The mass measured 18 × 10 × 6 cm, and contained diffuse ulcerated areas and purulent discharge. A complete excision of the mass was performed. There was no subsequent evidence of recurrence, according to a 13-month follow-up. As a rare benign vulvovaginal tumor, AMF can present on patients of an early reproductive age with rapidly growing, polypoidal pattern. The whole exon sequencing analysis revealed the genomic alterations, which may contribute to the occurrence of AMF.

Whole-exome sequencing identifies unique mutations and copy number losses in calcifying fibrous tumor of the pleura: report of 3 cases and review of the literature.

Calcifying fibrous tumor of the pleura (CFTP) is a rare mesenchymal tumor of unknown pathogenesis. The diagnosis often requires exclusion of other common entities. Our aim was to determine if genomic changes were associated with CFTP that could contribute to mechanisms underlying tumorigenesis. Three cases of CFTP with their corresponding uninvolved control lung tissue were identified. Two patients were male, and 1 was female (age range, 21-32 years). Tumors were multifocal in 2 cases and solitary in 1. Immunohistochemistry for STAT6, BCL-2, CD34, cytokeratin AE1/AE3, calretinin, desmin, S100, ALK, and ß-catenin was used. All immunohistochemistries were negative in CFTPs. DNA was isolated from all 3 pairs of CFTPs and matching normal lungs for whole-exome sequencing. Damaging, tumor-specific, coding variants were identified in 3 genes including multiple heterozygotic, de novo mutations in the Zinc Finger Protein 717 (ZNF717), fascioscapulohumeral muscular dystrophy-1 (FRG1) and cell division cycle 27 (CDC27) genes. Whole-exome sequencing revealed statistically significant, focal, tumor-specific copy number losses among all CFTPs including a large (302 kb) loss at 6p22.2 comprising 32 genes of the histone cluster 1 family and the hemochromatosis (HFE) gene. This is the first study to evaluate the molecular pathogenesis of CFTP and to identify novel deleterious mutations in ZN717, FRG1, and CDC27 genes as well as significant copy number losses on 8 chromosomes with a large loss common to all samples on chromosome 6. These mutations deleteriously altered coding domains in a manner predicted to be damaging to protein function and may contribute to CFTP tumorigenesis.

Fibroblastic and myofibroblastic tumors of children: new genetic entities and new ancillary testing.

Fibroblastic and myofibroblastic tumors comprise a morphologically diverse and biologically variable group of neoplasms that affect a wide age range. Specific entities tend to occur most frequently in infants and young children. Recent years have witnessed a proliferation of information concerning the unique biology of these tumors. In this report, I will review recent findings that serve to further characterize this group of neoplasms. Included will be newer information on fibrous hamartoma of infancy, infantile myofibromatosis, lipofibromatosis, and infantile fibrosarcoma and tumors resembling it, including primitive myxoid mesenchymal tumor of infancy and new genetic entities. I will also discuss the differential diagnosis, which includes spindle cell rhabdomyosarcoma, dermatofibrosarcoma protuberans, and calcifying aponeurotic fibroma.

Myxoinflammatory Fibroblastic Sarcoma: Review and Update.

Myxoinflammatory fibroblastic sarcoma is a rare soft tissue tumor with most occurring in the distal extremities of adult patients. It has a high rate of local recurrence and a low rate of metastasis. Because it may appear benign on clinical examination, and because the microscopic features are generally underrecognized, it is often inadequately treated and misdiagnosed. In this review, based upon experience and that of the literature, the intent is to highlight salient clinicopathologic features, detail the broad microscopic spectrum including high-grade aggressive variants, review the molecular features, and discuss its relation to hemosiderotic fibrolipomatous tumor.

[Desmoplastic fibroblastoma: a clinicopathologic analysis of 7 cases].

Objective: To investigate the clinical features, immunohistochemical and differential diagnosis of desmoplastic fibroblastoma. Methods: The clinical data and pathology features of 7 cases of desmoplastic fibroblastoma were collected and immunohistochemical study were carried out in all cases with a review of the literatures. Results: There were 2 males and 5 females, with age ranging from 31 to 71 years (average and mean age were 59 and 61 years, respectively). The tumors were located in extremities and abdomen (left toe and right toe, right foot back, left leg and right thigh, right forearm and left hepatic lobe). Clinically, the tumors presented as slow growing painless masses of long standing duration. Grossly, the tumors were well-circumscribed with firm, white to gray cut-off surface. Tumor size ranged from 1.2 to 4.0 cm in maximum diameter (average 3.0 cm). Microscopically, 2 cases were located in dermis, 4 cases were located in subcutaneous and 1 case was located in liver parenchyma. It was composed of spindle-shaped or stellate cells with a fibroblastic or myofibroblastic appearance, and sparsely scattered in densely fibrous or fibromyxoid background. There was small vascular component in tumor background. At high magnification, the tumor cells were medium size with abundant cytoplasm, and the nucleus were small and always with small nucleoli. In some cases, the tumor cells were slightly larger with enlarged nuclei, but without cellular atypical and mitosis. Immunohistochemical study showed that the tumor cells were strongly positive for vimentin, desmin, S-100 protein and CD34, but CKpan was negative. α-SMA showed focal positive in one case. Ki-67 index ranged from 1% to 2%. Four cases were followed-up (ranged from 11 to 21 months, average 16.5 months) and the patients had no recurrence after surgery. Conclusions: Desmoplastic firoblastoma is a rare soft benign tumor. The differential diagnosis includes other benign or low-grade fibroblastic/myofibroblastic lesions.

Calcifying Fibrous Tumor of the Tunica Vaginalis Testis: A Report of 2 Cases.

OBJECTIVE: To improve the clinical diagnosis and treatment of calcifying fibrous tumor (CFT) of the tunica vaginalis testis, we discussed clinical manifestations and pathologic features of CFT. MATERIALS AND METHODS: A retrospective analysis of 2 cases of CFT that occurred in our hospital was performed, and we also reviewed the literature and research reports. RESULTS: Both patients underwent local excision with testis preservation surgery, and pathology examination confirmed the presence of multiple CFTs of the tunica vaginalis testis. CONCLUSION: CFTs are rare, benign multiple lesions, and the recognition of which needs to be improved to avoid overtreatment. We are the first to describe 2 cases of CFT combined with hepatitis B, but additional studies are needed to confirm the relationship between these conditions.