Rhabdomyosarcoma or Fibrosarcoma? A Case of Large Ulcerated and Necrotic Lesion on the Forearm of a Newborn.

Congenital infantile fibrosarcoma (CIFS) is a rare malignant soft tissue tumor. The incidence of fibrosarcoma is estimated to be 0.3 per 100 000 population per year, and it accounts for less than 1% of all soft tissue sarcomas. We present a case of a 7-day-old newborn with a large ulcerated and necrotic lesion on the left forearm, which was initially misdiagnosed as rhabdomyosarcoma. Magnetic resonance imaging (MRI) revealed a soft tissue mass with cystic components affecting the forearm and distal humerus muscles. Fine-needle biopsy was performed and initially diagnosed as rhabdomyosarcoma but later confirmed as low-grade fibrosarcoma with positive immunostaining for vimentin. The patient underwent a transhumeral amputation with follow-up chemotherapy at a specialized oncology center. This case underscores the importance of interdisciplinary collaboration and specialized care in managing complex medical conditions in infants. Early detection and appropriate management of these tumors are essential for improving outcomes and reducing morbidity and mortality. Despite the rarity of this case, it serves as a reminder of the importance of considering neoplastic lesions in the differential diagnosis of soft tissue masses in newborns.

Unusual Case of Concurrent Retroperitoneal Congenital Infantile Fibrosarcoma and Cellular Type Congenital Mesoblastic Nephroma.

BACKGROUND: Although congenital infantile fibrosarcoma (cIFS) is a rare soft tissue sarcoma among children, it constitutes one of the most common soft tissue sarcomas during the first year of life. Congenital mesoblastic nephroma (CMN) is the most common benign renal tumor usually developing during the first 3 months of life. cIFS and cellular type CMN (cCMN) share not only similar histopathologic features but identical molecular genetic abnormality including the ETV6/NTRK3 fusion gene. Here, we report an unusual case of cIFS occurring with cCMN. CASE PRESENTATION: An 18-month-old girl presented with a 1-month history of abdominal distension and a few days' history of a palpable abdominal mass. A large heterogenous mass sized 9.0×11.2×11.6 cm on the right side of the abdomen and an isolated heterogenous lesion sized 4×4.5 cm within the right kidney were noted from the imaging study. Pathologic findings were consistent with cIFS and cCMN of the right kidney. In addition, both pathologic specimens contained the ETV6/NTRK3 fusion gene. CONCLUSION: Although cIFS and cCMN share similar histopathologic features and molecular genetic abnormality, simultaneous occurrence of these 2 types of tumor is exceedingly rare. To our knowledge, this is the first unusual case report of concurrent cIFS and cCMN.

Massive Fetal Transfusion During an Emergency Ex Utero Intrapartum Treatment for a Congenital Infantile Fibrosarcoma: A Case Report.

Although originally described to assist airway management of fetal congenital malformations with life-threatening airway obstruction, the indications for an ex utero intrapartum treatment (EXIT) have expanded to include surgical resection of lesions that are potentially incompatible with life in the absence of uteroplacental circulatory support. We describe the case of an infantile fibrosarcoma (IFS) that presented with fetal hydrops and was successfully managed with an emergency EXIT that necessitated the initiation of a massive fetal blood transfusion both with and without the support of uteroplacental circulation.

Congenital infantile fibrosarcoma of the glabella: Nuances of achieving surgical cure without cosmetic or functional deformity.

Congenital Infantile Fibrosarcoma is a rare neoplasm that typically presents during the first year of life, but uncommonly in the head and neck. We report a six-day old male presenting with an expanding mass of the right glabella associated with visual field obstruction. The patient underwent a two-staged procedure for surgical removal of the tumor due to the initially unclear pathologic diagnosis of the tumor, combined with the desire to close the defect while incurring minimal aesthetic or functional deformity. We describe this patient's postnatal presentation and curative surgical management and review the relevant literature to date.

Successful management of congenital/infantile fibrosarcoma presenting as large, non-healing buttock ulceration.

A two-year-old boy presented with a large, non-healing ulceration on his left buttock, which was originally noted as a brown patch present at birth. Punch skin biopsy was performed and histopathology revealed an atypical, pleomorphic, spindled proliferation in whorled fascicles replacing the dermis and trapping fat in the subcutis, consistent with a diagnosis of congenital/infantile fibrosarcoma. No evidence of metastatic spread was seen on imaging. The tumor was initially deemed unresectable owing to extent of local invasion. Neo-adjuvant chemotherapy caused significant tumor shrinkage and the patient underwent complete resection.

A case of congenital infantile fibrosarcoma in a newborn.

Infantile fibrosarcoma is a malignant tumor, which is most common in infants, preferentially localized in the lower limbs. An important prognostic factor of the disease is early diagnostics, both clinical and instrumental. The operative treatment of infantile fibrosarcoma is a leading treatment method. The article describes a clinical case of infantile fibrosarcoma in a newborn with fetal development of the disease.

A Case of Congenital Infantile Fibrosarcoma of the Bowel Presenting as a Neonatal Intussusception.

Neonatal intussusception of the intestinal tract is rare. However, most neonatal intussusceptions have an organic lead point. For the lead point to be a neoplasm is extremely rare. We report a case that presented with neonatal intussusception with a congenital infantile fibrosarcoma as the lead point. The detection of ETV6-NTRK3 gene fusion was useful, although the definitive diagnosis was achieved by a comprehensive evaluation including this gene analysis, standard histology and immunohistochemistry. Neonatal intussusception should be suspected to be caused by a neoplasm. If pathological diagnosis is difficult, molecular analysis should be utilized to diagnose congenital infantile fibrosarcoma.

Congenital Infantile Fibrosarcoma in the Premature Infant.

BACKGROUND: Congenital infantile fibrosarcoma (CIF) is rare and represents less than 1% of all childhood cancers. It is a tumor that originates in the connective fibrous tissue found at the ends of long bones and then spreads to other surrounding soft tissues. These lesions are typically large, grow rapidly, and can often be mistaken for teratomas. Diagnosis is confirmed by pathology, where cellular proliferation of fibroblasts occurs. Imaging is an important part of the diagnosis, which includes the use of magnetic resonance imaging and/or computed tomography scan. Although surgical resection is the primary treatment, chemotherapeutic agents may be used as adjuvant therapy. PURPOSE: To describe modalities for accurate diagnosis and treatment of CIF. METHODS/SEARCH STRATEGY: PubMed was searched using terms "congenital infantile fibrosarcoma" and "infantile fibrosarcoma." Eleven relevant, English language articles were identified and utilized in the preparation of this case presentation. FINDINGS/RESULTS: Complications addressed in this case presentation are prenatal diagnostic challenges, pharmacologic interventions in the setting of prematurity, immunosuppression, and acute liver and renal failure. Pharmacologic treatments will include chemotherapy agents, antimicrobial agents, as well as granulocyte colony-stimulating factor for immunosuppression. Nursing challenges included positioning and integumentary disturbances. IMPLICATIONS FOR PRACTICE: Utilization of diagnostic imaging and pathology to accurately identify and diagnose CIF is essential. IMPLICATIONS FOR RESEARCH: Safety and efficacy of chemotherapeutic agents in premature infants with CIF need to be established.

Congenital Infantile Fibrosarcoma Associated With a Lipofibromatosis-Like Component: One Train May Be Hiding Another.

Congenital infantile fibrosarcoma (CIFS) is a soft tissue sarcoma of infants mainly involving lower extremities and usually developing during the first year of life. At another end of the spectrum of pediatric fibroblastic lesions, lipofibromatosis is a rare benign infiltrative soft tissue tumor that affects children. The authors report in this study a particular presentation with a CIFS surrounded by lipofibromatosis-like areas. The presence of a surrounding benign tumor confused and delayed CIFS diagnosis.

Congenital intestinal fibrosarcoma with rapid recurrence requiring adjuvant chemotherapy.

A total of 16 cases of congenital fibrosarcoma have been reported from 1975 to March 2015. Five of the 16 had abnormal fusion between erythroblast transformation specific translocation variant 6 and neurotrophin recptor gene neurotrophic tyrosine kinase, receptor, type 3 (ETV6-NTRK3); in another five out of 16 this was absent, and six were not tested. All were managed by surgical resection but none involved metastasis. Herein we report the case of a newborn baby girl with congenital fibrosarcoma negative for ETV6-NTRK3 gene fusion, who presented with ileal perforation and positive resection margin. She had rapid recurrence with lymph node metastasis treated with postoperative chemotherapy. There was no further recurrence at >3 years of follow up.

Recurrent BCOR internal tandem duplication and BCOR or BCL6 expression distinguish primitive myxoid mesenchymal tumor of infancy from congenital infantile fibrosarcoma.

Primitive myxoid mesenchymal tumor of infancy is a rare sarcoma that preferentially affects infants. It can be locally aggressive and rarely metastasizes, but the long-term outcome of children with this tumor is mostly unknown. Histologically, it is characterized by primitive cells with abundant myxoid stroma. Internal tandem duplication of B-cell CLL/lymphoma 6 (BCL6)-interacting co-repressor (BCOR) exon 15 has recently been described in clear cell sarcoma of kidney, central nervous system high-grade neuroepithelial tumor with BCOR alteration, and primitive myxoid mesenchymal tumor of infancy. Herein, we report five cases of primitive myxoid mesenchymal tumor of infancy: three girls and two boys with mean age of 6.5 months. The tumors were located in the paraspinal region (n=3), back (n=1), or foot (n=1) and ranged in size from 2.5 to 10.2 cm. BCOR internal tandem duplication was confirmed by PCR and sequencing in all five cases. The minimally duplicated region consisted of nine residues, which is shorter than was previously reported in other BCOR-associated tumors. To assess the clinical value and specificity of the BCOR internal tandem duplication, a group of 11 ETV6-rearranged congenital infantile fibrosarcomas were evaluated and no BCOR internal tandem duplication was identified in any case. Though not detected in congenital infantile fibrosarcomas, BCOR and BCL6 immunoreactivity was present in >90% of the nuclei of tumor cells in each of the five primitive myxoid mesenchymal tumor of infancy. The presence of BCOR internal tandem duplication in all five primitive myxoid mesenchymal tumors of infancy provides evidence that it is a recurrent somatic abnormality and substantiates the concept that this tumor is a unique sarcoma of infancy. Our findings indicate that identification of BCOR internal tandem duplication and/or nuclear immunoreactivity for BCOR or BCL6 can aid in the diagnosis of primitive myxoid mesenchymal tumor of infancy and help to differentiate it from congenital infantile fibrosarcoma.

Congenital infantile fibrosarcoma mimicking a cutaneous vascular lesion: a case report and review of the literature.

Congenital infantile fibrosarcoma (CIFS) is a rare neoplasm of infancy that occurs most frequently in the extremities, and when presenting in the skin, may sometimes resemble infantile hemangiomas or other vascular lesions. Clinically, these tumors differ from hemangiomas in the time of onset, morphology, and growth pattern and must be evaluated histologically for definitive diagnosis. We describe an infant with a neoplasm involving the distal left forearm initially presumed to be a vascular lesion after evaluation by two separate ultrasound studies. He presented at seven weeks of life with a multinodular lesion that had enlarged significantly since birth, and the skin biopsy revealed a fibrosarcoma. This case highlights an unusual cutaneous presentation of CIFS, which varies in appearance from the previous 12 cases reported in the literature. We review the clinical manifestations of these congenital masses and emphasize early diagnosis for conservative therapy and improved prognosis.

Congenital mesoblastic nephroma: a study of 19 cases using immunohistochemistry and ETV6-NTRK3 fusion gene rearrangement.

Mesoblastic nephroma (MN) is the most common renal tumour in the first 3 months of life and accounts for 3-5% of all paediatric renal neoplasms. To further understand the morphological variants of MN, we identified 19 cases of MN (five classic, eight cellular and six mixed) and examined each case for markers known to be important in urogenital embryological development (PAX8, WT1 and RCC), stem cell associated markers (Oct 4, CD34 and c-kit), muscle/myofibroblastic markers (muscle specific actin, calponin and h-caldesmon), aberrant transcription factors, cell cycle regulation and other oncogenic proteins (p16, cyclin D1 and beta-catenin). Fluorescence in situ hybridisation (FISH) testing for ETV6-NTRK3 gene fusion/rearrangement revealed further differentiation between the subtypes with ETV6-NTRK3 gene fusion detected in 0/5 of the classic MN, 8/8 of the cellular MN and 5/6 of the mixed MN cohorts, respectively. Our results conclude that cyclin D1 and beta-catenin may be useful markers for differentiating between cellular MN and classic MN when the histology is not conclusive. The absence of expression of stem cell markers and markers involved in urogenital development suggests that MN is not a nephroma and most likely represents a soft tissue tumour, with congenital infantile fibrosarcoma representing cellular MN with a predilection to arise in the kidney. In addition, the immunophenotype and genetic fingerprint of mixed MN most likely represents a heterogenous group of tumours that are mostly cellular type, with areas that are phenotypically less cellular.

[Congenital Fibrosarcoma of the Left Index Finger - An Unusual Case]. / Kongenitales Fibrosarkom am linken Zeigefinger - ein ungewöhnlicher Fall.

Congenital fibrosarcoma is a rare mesenchymal soft tissue tumour, which most commonly develops in the peripheral extremities during infancy. Diagnostic work-up is a challenge for clinicians and pathologists alike, because in many cases the lesion initially resembles a haemangioma on macroscopic inspection. A 4-month-old boy presented with a strongly vascularised tumour of the left index finger, which had been diagnosed as a capillary haemangioma by means of a biopsy performed in another facility. The lesion had been treated with systemic and intralesional cortisone injections. Due to ulceration and the risk of infection, the tumour mass was resected with the index finger being preserved. The histological appearance was inconclusive. PCR revealed a congenital fibrosarcoma. 2 years after surgery, the boy is free from recurrence.

Primitive Spindle Cell Neoplasm of Ileum with Extensive Heterotopic Cartilage, Presenting as Acute Abdomen in a 6-Day-Old Neonate.

Neonatal intestinal masses with spindle cell morphology have broad differential diagnoses and require a multidisciplinary approach to make the final diagnosis. Spindle cell masses with heterotopic cartilage in the gastrointestinal tract are very rare, and, to our knowledge, have not previously been reported in the neonate. Here we present a case of intestinal primitive spindle cell neoplasm with extensive heterotopic cartilage that manifested initially as acute abdomen in a 6-day-old term infant. Plain radiography demonstrated pneumoperitoneum, prompting diagnostic laparotomy that identified a perforated mass involving the midileum. Histologic and immunohistochemical examination demonstrated an infiltrative spindle cell tumor most compatible with infantile fibrosarcoma (IFS) by a process of exclusion, with nodules of mature heterotopic cartilage. Additional staging studies did not reveal any evidence of residual or metastatic disease. Recognition of this rare variant of IFS will aid in differentiation from other neonatal intestinal mesenchymal tumors.