Infantile digital fibroma/fibromatosis: a clinicopathologic and immunohistochemical study of 69 tumors from 57 patients with long-term follow-up

Update of pediatric soft tissue tumors with review of conventional MRI appearance-part 1: tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors

There are numerous soft tissue tumors and tumor-like conditions in the pediatric population. Magnetic resonance imaging is the most useful modality for imaging these lesions. Although certain soft tissue lesions exhibit magnetic resonance features characteristic of a specific diagnosis, most lesions are indeterminate, and a biopsy is necessary for diagnosis. We provide a detailed update of soft tissue tumors and tumor-like conditions that occur in the pediatric population, emphasizing each lesion's conventional magnetic resonance imaging appearance, using the recently released 5th edition of the World Health Organization Classification of Soft Tissue and Bone Tumors as a guide. In part one of this review, pediatric tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors are discussed. In part two, vascular lesions, fibrohistiocytic tumors, muscle tumors, peripheral nerve sheath tumors, tumors of uncertain differentiation, and undifferentiated small round cell sarcomas are reviewed. Per the convention of the WHO, these lesions involve the connective, subcutaneous, and other non-parenchymatous-organ soft tissues, as well as the peripheral and autonomic nervous system.

Pediatric and Infantile Fibroblastic/Myofibroblastic Tumors in the Molecular Era

Pediatric fibroblastic/myofibroblastic tumors are rare but include a wide variety of benign to malignant tumors. Given their uncommon frequency, they may present as a diagnostic dilemma. This article is focused on using clinical and pathologic clues in conjunction with the increasingly relevant and available molecular techniques to classify, predict prognosis, and/or guide treatment in these tumors.

Recurrent infantile digital fibromatosis with HPV infection: a case report

Infantile digital fibromatosis is a rare, benign fibrous tumor among infants usually limited to fingers and toes. Most cases present themselves with round eosinophilic inclusion bodies of different sizes, similar to erythrocyte in the parakarytoplasm. Although infantile digital fibromatosis had been observed with a tendency of spontaneous regression after a rapid phase of growth in some reports, the recurrence rate of early surgical intervention remains high. And the mechanism of recurrence is still unknown. Human papillomavirus (HPV), as a circular icosahedral double-stranded DNA virus, is famous for its remarkable significant correlation with cervical cancer. However, the reports about the possible relationship of recurrent infantile digital fibromatosis and HPV infection are rare and inconsistent. Here, we report a recurrent case of infantile digital fibromatosis after surgical resection. Pathological biopsy of the recurrent site not only identified the diagnosis of infantile digital fibromatosis again, but found the sign of HPV infection. Family history indicated that the patient's grandmother had a history of verruca plana. After complete resection of recurrence, the tumor recurred again and the case is still being followed up. The unique case may serve as a clue to the pathogenesis of the relationship between recurrent infantile digital fibromatosis and HPV infection.

Inclusion body fibromatosis - A report of four cases and review of literature

Inclusion body fibromatosis (IBF) also called the “Reye tumor” is a rare spindle cell proliferation with distinct clinicopathological features. This is a report of four cases of IBF from a single institute. Typical location, age, size of the lesion, bland histology, and paranuclear inclusions are the distinguishing features of this entity. Medical literature search reveals very few series of cases of IBF, the remaining cases being in the form of case reports. The aim of this report is to highlight the typical features of this rare entity.

Terminal osseous dysplasia presenting with intracytoplasmic inclusion bodies in digital fibromas

Terminal osseous dysplasia is a rare, X-linked syndrome, presumptively embryonic lethal in males, which has recently been described with highly characteristic skin findings. The presence of intracytoplasmic inclusion bodies in fibroblasts has been considered an exclusive finding of infantile digital fibromatosis. This is the first report documenting digital fibromas with intracytoplasmic inclusion bodies in a classic case of terminal osseous dysplasia.

The Use of Cryotherapy to Treat Infantile Digital Fibromatosis with a Functional Deficit: A Case Report

Infantile Digital Fibromatosis (IDF) is a rare benign lesion that can affect the fingers, often appearing at birth or early on in life. Treatment is controversial due to a high recurrence rate following surgical excision, and the tendency of the lesions to regress or resolve completely after the age of one year. Functional loss has rarely been described. We describe a case of IDF with joint contracture and significant functional deficit that was treated with cryotherapy and post procedural occupational therapy with an excellent result. Indications for treatment and cryotherapy as a therapeutic modality for IDF are discussed.

CT and MRI of superficial solid tumors

Superficial solid masses are common conditions in clinical practice, however, some of which can be easily diagnosed and others would be difficult. Although imaging of superficial masses is not always characteristic, it would be helpful to give a definitive diagnosis or narrow a differential diagnosis. Crossing-section imaging can depicture the masses directly, find some pathognomonic signs and demonstrate their relationship with adjacent structures, which can provide decision support for clinician's reference. Computed tomography (CT) can be used to detect calcifications and bone erosion which could not be seen on radiographs. Magnetic resonance imaging (MRI) is the preferred way for evaluating soft tissue lesions and provides information on hemorrhage, necrosis, edema, cystic and myxoid degeneration, and fibrosis. Other advantages of MRI are its superior soft tissue resolution and any profile imaging, which can aid the assessment of extension and adjacent infiltration. Positron emission tomography (PET)/CT and PET/MRI have been increasingly used in bone and soft tissue sarcomas and provides advantages in the initial tumor staging, tumor grading, therapy assessment, and recurrence detection. Therefore, imaging examination can play an important role in treatment decision making for superficial solid tumors. Here we review the important conditions presenting as superficial mass and show the imaging of typical cases diagnosed in our hospital.

Nonepithelial Tumors and Tumor-like Lesions of the Skin and Subcutis in Children

This overview of mesenchymal tumors presenting in the skin and/or subcutis in children brings together the range of neoplasms and hamartomas which are seen in this age-group. It is not surprising from the perspective of the pediatric or general surgical pathologist that vascular anomalies, including true neoplasms and vascular malformations, are the common phenotypic category. Since there is considerable morphologic overlap among these lesions, clinicopathologic correlation may be more important than for many of the other mesenchymal tumors. The skin and subcutis are the most common sites of clinical presentation for the infantile myofibroma which is the most common of fibrous mesenchymal tumors in children. Several of the other mesenchymal tumors are more common adults-like dermatofibrosarcoma protuberans, but nonetheless have an important presence in children, even as a congenital neoplasm. A lipomatous tumor in a young child should be considered as a possible manifestation of an overgrowth syndrome.

Infantile Digital Fibroma: A Rare Fibromatosis

Infantile digital fibroma is a rare benign lesion that usually occurs during the first 2 years of life. It can be multiple, but it is usually a single lesion. If it grows large enough it can cause joint deformities or interfere with everyday activities. Microscopically, the neoplastic cells usually have inclusion bodies that are best highlighted with a Masson trichrome stain but can often be seen on hematoxylin-eosin staining. Treatment for this entity is usually watchful waiting because of its ability to spontaneously regress, but excision is recommended if the lesion is symptomatic. More recently, fluorouracil or injectable steroids have shown great promise in inducing regression without the complications that accompany surgery.

Acral manifestations of soft tissue tumors

This group of biologically diverse entities is united by topographic localization to the hands and feet. Categorizing tumors by body site narrows the differential into a short list of possibilities that can facilitate accurate and rapid diagnosis. The goal of this review is to provide a practical approach to soft tissue tumors of acral locations for clinicians, pathologists, and researchers alike. What ensues in the following text is that tight coupling of the clinical picture and histopathologic findings should produce the correct diagnosis, or at least an abbreviated differential. The salient clinicopathologic, immunohistochemical, and molecular features are presented alongside current treatment recommendations for each entity.

CTNNB1 (β-Catenin)-altered Neoplasia: A Review Focusing on Soft Tissue Neoplasms and Parenchymal Lesions of Uncertain Histogenesis

β-catenin (CTNNB1) is a key regulatory molecule of the Wnt signaling pathway, which is important for tissue homeostasis and regulation of cell proliferation, differentiation, and function. Abnormal stabilization and nuclear accumulation of β-catenin as a consequence of missense mutations or alternative molecular mechanisms occurs at a high frequency in a variety of epithelial cancers. In mesenchymal neoplasia, the role of β-catenin has been traditionally considered limited to desmoid-type fibromatosis. However, the spectrum of β-catenin-driven (β-catenin-altered) neoplasia of mesenchymal origin has been steadily widening to include, in addition to desmoid tumors, a variety of benign and intermediate-biology neoplasms of soft tissue (intranodal palisaded myofibroblastoma), head and neck (juvenile nasopharyngeal angiofibroma and sinonasal hemangiopericytoma/glomangiopericytoma), and ovarian (microcystic stromal tumor) origin. In addition, several old and newly reported distinctive site-specific β-catenin-driven parenchymal neoplasms of uncertain histogenesis have been well characterized in recent studies, including solid-pseudopapillary neoplasm of the pancreas and its recently described ovarian counterpart, sclerosing hemangioma of lung and calcifying nested stromal-epithelial tumor of the liver. This review addresses the most relevant pathobiological and differential diagnostic aspects of β-catenin-altered neoplasms with emphasis on site-specific histologic and biological variations. In addition, the morphologic overlap and analogy as well as distinctness between these uncommon tumors will be presented and discussed. Furthermore, a note is made on association of some of these lesions with hereditary tumor syndromes, in particular with the familial adenomatous polyposis coli.

Intranodal palisaded myofibroblastoma: another mesenchymal neoplasm with CTNNB1 (β-catenin gene) mutations: clinicopathologic, immunohistochemical, and molecular genetic study of 18 cases

Intranodal palisaded myofibroblastoma is a benign, lymph node-based myofibroblastic tumor of unknown pathogenesis. We report the clinicopathologic, immunohistochemical, and molecular genetic features of this rare entity. The study cohort consisted of 14 men and 4 women ranging in age from 31 to 65 (mean, 47; median 49) years with tumors arising in inguinal lymph nodes (n=15), a neck lymph node (n=1), and undesignated lymph nodes (n=2). Most individuals presented with a painless mass or lump. Possible trauma/injury to the inguinal region was documented in 4 cases. Tumors ranged in size from 1.0 to 4.2 (mean, 3.1; median; 3.0) cm. Microscopically, the process presented as a well-circumscribed, oftentimes pseudoencapsulated nodule (n=17) or nodules (n=1). Tumors consisted of a cellular proliferation of cytologically bland, spindled cells arranged in short fascicles and whorls within a finely collagenous (n=11) or myxocollagenous (n=7) matrix. In 12 tumors, scattered fibromatosis-like fascicles of spindled cells were noted. Histologic features characteristic of the process included nuclear palisades (n=16 cases), collagenous bodies (n=15), and perinuclear intracytoplasmic hyaline globules (n=10). Mitotic activity ranged from 0 to 8 (mean, 2; median, 1) mitotic figures/50 high-powered fields with no atypical division figures identified. Immunohistochemically, all tumors tested expressed smooth muscle actin and/or muscle-specific actin (n=5, each), and nuclear β-catenin and cyclin D1 (n=8, each). The latter 2 results prompted a screening for mutations in the β-catenin gene glycogen synthase kinase-3 β phosphorylation mutational "hotspot" region in exon 3 using polymerase chain reaction amplification and Sanger sequencing. Single nucleotide substitutions leading to missense mutations at the protein level were identified in 7 of 8 (88%) analyzed tumors and are responsible for the abnormal expression of β-catenin and cyclin D1. These results demonstrate that mutational activation of the β-catenin gene is likely a pivotal event in the pathogenesis of intranodal palisaded myofibroblastoma.

Pachydermodactyly: a review

Synovitis is the characteristic feature of inflammatory joint disease. If synovitis is localized to interphalangeal joints, rheumatoid arthritis, psoriatic arthritis, and juvenile idiopathic arthritis are among the most common differential diagnoses. The absence of pain, tenderness, and limitation of function despite progressive swelling of proximal interphalangeal joints suggests an alternative diagnosis, for example pachydermodactyly (PDD). This is a benign disease, associated with asymptomatic, progressive swelling of periarticular soft tissue, which usually occurs in young males. PDD is probably the result of repetitive mechanical stimulation. One hundred and twenty-one cases have been reported in the literature. Some of these were initially misdiagnosed and treated for inflammatory arthritis. We provide a comprehensive review of the literature on pachydermodactyly to promote awareness of this rare but important differential diagnosis of arthritis.

Congenital and infantile benign skin lesions affecting the hand and upper extremity, part 2: nonvascular neoplasms

This article is part 2 of a 2-part series presented to aid the hand surgeon in becoming familiar with dermatological lesions that may be present on the upper extremity during infancy. The discussion focuses on nonvascular neoplasms grouped into the following categories: epithelial, melanocytic, histiocytic, dermal, fibroblastic, and adipocytic neoplasms. Diagnostic tips are offered, including clinical photographs, to help differentiate between these lesions. In addition, the recommended treatment for each is discussed.

Myofibroblastoma: report of a rare entity in the pediatric population

Fibroblastic and myofibroblastic tumors constitute an important group of neoplasms in children and adolescents. These span the full spectrum of clinical behavior, ranging from benign to intermediate and malignant. We report a case of a benign mesenchymal tumor with myofibroblastic differentiation in a 9-year-old girl arising in the left groin that met the histologic features described for myofibroblastoma in adults. Two types are recognized in adults: angiomyofibroblastoma and mammary-type myofibroblastoma of soft tissue. Our case shared features of both these subtypes but was not typical of either one, and we therefore designated our case simply as "myofibroblastoma." Our case showed expression of estrogen receptor protein, which is characteristic of adult lesions, but not a deletion of 13q14, as has been reported in some adult cases. In the English-language literature, only 6 cases have been reported in patients under 21 years of age, and all but 1 were teenagers. Pediatric surgeons, oncologists, and pathologists should be aware that such a benign entity can occur in this patient population and could be confused with other lesions, including malignant ones.

Case for diagnosis

Infantile digital fibromatosis or Reye's tumor is a benign fibroproliferative tumor, the etiopathogenesis of which has yet to be fully clarified. It typically presents at birth or in the first year of life and is characterized by a firm, flesh colored or erythematous nodule or nodules located on the digits. These lesions tend to regress spontaneously.

Fibroblastic and myofibroblastic tumors in children and adolescents

Fibroblastic and myofibroblastic tumors in children and adolescents are a relatively common group of soft tissue proliferations that range from reactive to hamartomatous to neoplastic, with a full spectrum of benign, intermediate, and malignant neoplasms. These lesions are diagnostically challenging because of morphologic and immunohistochemical overlap, despite significant clinical, genetic, and prognostic differences. The fibromatoses are a major subgroup, and all types of fibromatoses can occur in the 1st 2 decades of life. Intermediate and malignant fibroblastic-myofibroblastic tumors are an important group that includes variants of fibrosarcoma and other tumors with recurrent cytogenetic or molecular genetic abnormalities and low metastatic potential. Pathologic examination is enhanced by adjunct techniques, such as immunohistochemistry, cytogenetics, and molecular genetics, although morphology provides the ultimate criteria for a specific diagnosis. This article reviews the clinicopathologic features of fibroblastic and myofibroblastic tumors with an emphasis on the unique aspects of these neoplasms in children and adolescents, the use of diagnostic adjuncts, and differential diagnoses.

[Inclusion body fibromatosis: a case report]

Infantile digital fibromatosis or inclusion body fibromatosis is a rare, benign fibroproliferative lesion with recurrent potential that occurs on the digits of infants. A highly characteristic morphologic finding is the presence of paranuclear inclusion within the tumoral cells. We report here a case occurring in an 8-month-old infant with 2 asynchronous lesions of the toes.

Pediatric fibroblastic and myofibroblastic lesions

Fibrous lesions of infancy and childhood are a heterogeneous group of entities composed predominantly of fibroblasts and myofibroblasts, ranging from reactive lesions to neoplasms with a range of malignant potential. Although rare, their correct recognition by histopathology is important clinically as they exhibit a wide range of behaviors and may be associated with distinct underlying syndromes. Contributions from molecular diagnostics have enabled more accurate diagnosis, and have changed our concepts of some tumor types. In this review, we discuss the clinicopathologic spectrum of fibroblastic and myofibroblastic lesions of childhood and adolescence.

Intra-lesional steroid for the management of symptomatic Infantile Digital Fibromatosis

BACKGROUND

Infantile Digital Fibromatosis (IDF) is a benign, often asymptomatic nodular proliferation of fibrous tissue occurring almost exclusively on the extremities. Conventional treatment has included radical surgery but this is associated with a high level of recurrence. Whilst some authors suggest a strictly conservative approach, this is unacceptable when lesions become symptomatic from pain, contracture formation or functional deformity

METHODS

We present a retrospective analysis of 12 symptomatic lesions of which 7 were treated with a novel technique of intra-lesional steroid. From 2004-2009, a total of ten patients received treatment for symptomatic IDFs. Patients were followed-up for an average of 5 years 9 months (range 8-131 months).

RESULTS

Corticosteroid was well tolerated with no significant complications and was associated with lower morbidity that compared with surgery. There was no significance difference between rate of recurrence (1/7 vs. 5/10) for those treated with corticosteroid than compared to those patients who underwent surgery (p = 0.3) but the study is underpowered.

CONCLUSIONS

This is the first ever study to look at the role of intra-lesional steroid in the management of IDF. Whilst the majority of asymptomatic Infantile Digital Fibromatoses can be safely observed until natural resolution, intra-lesional corticosteroid is a safe and well-tolerated alternative to surgery for all symptomatic digital fibromatoses of infancy. We suggest it replaces surgery as first-line treatment but look forward to a large multicentre trial to allow comparison.

Myofibroblastic Tumors in Children

Pediatric myofibroblastic tumors comprise a clinically and pathologically heterogeneous group of neoplasms, including benign tumors, those of intermediate biologic potential, and frankly malignant examples (Box 1). Proper classification is critical for appropriate prognostication, clinical management, and, in some cases, identification of familial syndromes. Unlike for many other soft tissue tumors, immunohistochemistry plays a limited role in the diagnosis of pediatric myofibroblastic tumors, with notable exceptions. Understanding the molecular genetics underlying the pathogenesis of several tumor types in this group has led to improved tools for diagnosis. This article discusses the clinical and pathologic features of myofibroblastic tumors in children, with special emphasis on differential diagnosis.

Congenital infantile digital fibromatosis: a case report and review of the literature

Infantile digital fibromatosis (IDF) is a rare benign fibroproliferative tumor of early childhood. IDF preferentially affects the fingers and the toes. Malignant transformation or metastases have never been reported. Surgical treatment has been advocated previously but local recurrences were observed frequently. Recent literature supports clinical surveillance without any medical or surgical intervention as spontaneous regression usually occurs after two to three years. A six-month-old Caucasian girl with IDF on the left fourth digit is presented here. The tumor progressively increased in size after birth. Topical imiquimod cream and diflucortolone valerate cream, both displaying antifibrotic properties, had no effect on tumor growth. Currently the lesion size remains stable without any treatment. Early recognition of IDF is important in order to avoid unnecessary surgical intervention that may prove to be potentially aggravating, unless serious functional or cosmetic concerns intervene. Parents should be reassured concerning the benign nature of IDF and be informed that spontaneous involution of IDF might be expected.