Soft tissue tumors in first year of life: a report of 190 cases

Infantile Fibrosarcoma and Other Spindle Cell Neoplasms of Infancy. A Review of Morphologically Overlapping yet Molecularly Distinctive Entities

BACKGROUND

Regardless of age at presentation, many soft tissue neoplasms have overlapping histopathologic and immunophenotypic features to serve as a diagnostic challenge.

CASE REPORT

We reported a case of a spindle cell neoplasm in an infant, which was initially considered a vascular anomaly clinically and an eventual biopsy revealed marked inflammation with a spindle cell component that was resolved as an infantile fibrosarcoma with an ETV6 break-apart.

CONCLUSION

The context of this case lead to a further consideration of various other spindle cell neoplasms arising predominantly in the soft tissues during the infancy period as defined by the first two years of age. Though sharing similar morphologic features, these tumors can be categorized into several molecular genetic groups, which have provided both diagnostic and pathogenetic insights as well as treatment options in some cases.

Multicentric infantile myofibromatosis with extensive involvement limited to bone

Infantile myofibromatosis (IM) is the most common benign fibrous tumor of infancy, characterized by the development of single or multiple nodules in the skin, soft tissues, bone, and/or viscera. Multicentric forms are less frequent and can affect different tissues simultaneously and their prognosis depends on their extension and visceral involvement. Rarely, these forms are limited to the skeleton, in which case the absence of extraosseous lesions makes it difficult to suspect this entity. We present the case of an infant with multiple radiolucent lesions involving the skull, ribs, spine, and long bones, discovered in a radiological study performed after a minor trauma. A broad differential diagnosis was considered based on the osteolytic and polyostotic nature of the lesions on imaging studies. This report details and illustrates the typical radiological findings in bony involvement of IM, which suggest this disorder over other diagnostic options.

Avoidance of surgery for head and neck infantile myofibromatosis using imatinib monotherapy

Describe a novel use for a kinase inhibitor, imatinib, in young children with a known activated somatic mutation in PDGFR-beta. Two patients with infantile myofibromatosis treated with imatinib. Case description of evaluation, diagnosis and treatment decisions for infantile myfibromatosis of the head and neck. Description of medical therapy for infantile myofibromatosis in these patients. For function threatening myofibromas of a known genotype, in infants, targeted medical therapy is a treatment option.

Management of Refractory Pediatric Sarcoma: Current Challenges and Future Prospects

Paediatric sarcomas are a heterogeneous group of disorders constituting bone sarcoma and various soft tissue sarcomas. Almost one-third of these presents with metastasis at baseline and another one-third recur after initial curative treatment. There is a huge unmet need in this cohort in terms of curative options and/or prolongation of survival. In this review, we have discussed the current treatment options, challenges and future strategies of managing relapsed/refractory paediatric sarcomas. Upfront risk-adapted treatment with multidisciplinary management remains the main strategy to prevent future recurrence or relapse of the disease. In the case of limited local and/or systemic relapse or late relapse, initial multimodality management can be administered. In treatment-refractory cases or where cure is not feasible, the treatment options are limited to novel therapeutics, immunotherapeutic approach, targeted therapies, and metronomic therapies. A better understanding of disease biology, mechanism of treatment refractoriness, identifications of driver mutation, the discovery of novel targeted therapies, cellular vaccine and adapted therapies should be explored in relapsed/refractory cases. Close national and international collaboration for translation research is needed to fulfil the unmet need.

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.

Expanding the Spectrum of Pediatric NTRK-rearranged Mesenchymal Tumors

Pediatric mesenchymal tumors harboring variant NTRK fusions (ETV6-negative) are being increasingly described; however, the histologic and clinical features of these variant NTRK tumors and their relationship to classic infantile fibrosarcoma are not well characterized. A better understanding of the clinicopathologic features of these tumors is necessary, and would aid in both early diagnosis and treatment. Therefore, the aim of this study was to characterize a series of pediatric NTRK-rearranged mesenchymal tumors, including classic ETV6-NTRK3 fused tumors and tumors with variant (non-ETV6) NTRK fusions. The clinical features, morphology, immunophenotype, and genetics of 12 classic ETV6-NTRK3 fused infantile fibrosarcoma and 18 variant NTRK-rearranged mesenchymal tumors were evaluated. For both classic and variant groups, the age at diagnosis ranged from birth to 15 years (median, 4 mo) with no sex predilection; the most common sites involved were the extremities and trunk. The rate of local recurrence and metastasis were not significantly different (recurrence rate: 11% classic, 40% variant; metastatic rate: 18% classic, 25% variant). Classic and variant NTRK tumors had an overlapping spectrum of histologic features, containing haphazardly arranged primitive cells in a myxoid background and/or spindle cells in long fascicles. Both groups showed diffuse pan-TRK expression by immunohistochemistry. Otherwise, the immunoprofile was nonspecific, but similar between both groups. No statistical difference was seen in any clinicopathologic feature between the classic ETV6-NTRK3 and variant fusion cohorts. Pediatric NTRK-rearranged mesenchymal tumors with both classic and variant fusions likely represent a spectrum of disease with shared, recognizable cliniopathologic features.

Surgical treatment of pediatric rhabdomyosarcoma in the parameningeal-nonparameningeal region

OBJECTIVES

Rhabdomyosarcoma (RMS) involving the parameningeal-nonparameningeal region (PNP) is relatively rare in pediatric patients (PPs). The current study aimed to report the outcomes of RMS-PNP-PPs who received surgical resection combined with concurrent flap reconstruction.

METHODS

A retrospective study was conducted concerning RMS-PNP-PPs who received combined skull-maxillofacial resection with flap reconstruction during the period from 2012 to 2016. Predictive factors for recurrence-free survival (RFS), metastasis-free survival (MFS), and overall survival (OS) were preliminarily identified by Kaplan-Meier analysis.

RESULTS

A total of 16 RMS-PNP-PPs were finally enrolled; recurrence, metastasis and death were found in 7, 7 and 5 patients, respectively. Following surgical ablation involving the skull base and maxillofacial region, reconstruction was performed with a local flap in 9 patients, a latissimus dorsi flap in 3 patients, and an anterolateral thigh flap in 4 patients. Through univariate analysis, we demonstrated that the primary site + surgical margins, postoperative RT/CT + Ki-67/Bcl-2 IHC, and surgical margins + Ki-67/Bcl-2 IHC could be used as the preliminarily prognostic factors for RFS, MFS and OS, respectively.

CONCLUSIONS

RMS-PNP-PPs showed poor prognosis even when surgical resection combined with flap reconstructions was performed. Achieving a clear surgical margin and good conduction of postoperative RT/CT should be taken into consideration to acquiring a better surgical outcome.

INI1 negative sarcoma diagnosed as malignant rhabdoid tumor presenting as hydrops fetalis metastatic to the placenta: a case report and review of the literature on congenital sarcomas

Rhabdoid tumor is a highly aggressive sarcoma found in young children that occurs in the kidney, central nervous system and soft tissue sites. Rarely, it presents in the fetus or neonate and is associated with a dismal prognosis. We report a case of a 28-week gestation fetus presenting with hydrops fetalis who died soon after delivery, found at autopsy to have a rhabdoid tumor of the thoracic cavity with placental metastases and provide a review of the literature of congenital sarcomas.

TRK Fusion Cancers in Children: A Clinical Review and Recommendations for Screening

Chromosomal translocations involving the NTRK1, NTRK2, and NTRK3 genes (TRK fusions), which encode the neurotrophin tyrosine kinase receptors TRKA, TRKB, and TRKC, can result in constitutive activation and aberrant expression of TRK kinase. Certain cancers almost universally harbor TRK fusions, including infantile fibrosarcoma, cellular congenital mesoblastic nephroma, secretory breast cancer, and mammary analog secretory carcinoma of the salivary gland. TRK fusions have also been identified at lower frequencies across a broad range of other pediatric cancers, including undifferentiated sarcomas, gliomas, papillary thyroid cancers, spitzoid neoplasms, inflammatory myofibroblastic tumors, and acute leukemias. Here we review the prevalence and diseases associated with TRK fusions and methods of detection of these fusions in light of the recent development of selective TRK inhibitors, such as larotrectinib, which demonstrated a 75% response rate across children and adults with TRK fusion cancers. We provide recommendations for screening pediatric tumors for the presence of TRK fusions, including the use of immunohistochemistry or fluorescence in situ hybridization for patients with tumors likely to harbor TRK fusions. Further, we recommend next-generation sequencing for tumors that have a relatively low prevalence of TRK fusions, both to identify patients who may benefit from TRK inhibition and to identify other targetable oncogenic drivers that exist in the same tumor types.

Early Surgery Is Feasible for a Very Large Congenital Infantile Fibrosarcoma Associated With Life Threatening Coagulopathy: A Case Report and Literature Review

Background: Congenital infantile fibrosarcoma (CIF) is a rare malignant soft tissue tumor that predominantly occurs in children under 1 year of age. CIF is frequently misdiagnosed with other conditions like hemangioma of infancy, infantile fibromatosis, or kaposiform hemangioendothelioma. Disseminated intravascular coagulopathy (DIVC) is rarely reported to be associated with CIF. Case presentation: We describe an infant who presented with a large mass over the right arm. She was initially treated conservatively as hemangioma but was later confirmed by tissue histopathological examination to have CIF as the mass rapidly increased in size. She developed massive intra-tumoral bleed with DIVC whilst receiving neoadjuvant chemotherapy requiring multiple blood products transfusion. An urgent near-total resection of the tumor was performed in view of life threatening bleeding despite multiple blood transfusions. Post-operatively, she received further adjuvant chemotherapy. Subsequently, she remained in complete remission 32 months off-treatment and has full function of the affected limb. Conclusions: CIF is an important condition to be considered in infant who has large mass over the extremity. DIVC could be associated with large CIF and when it occurs can be life-threatening. Whenever feasible early surgery should be performed in very young patients with large CIF to prevent mortality from bleeding.

Infantile NTRK-associated Mesenchymal Tumors

Pediatric fibroblastic/myofibroblastic lesions are a relatively common group of tumors with varying morphologies, for which the molecular mechanisms are becoming increasingly well characterized. Congenital infantile fibrosarcoma (CIFS), perhaps the most well studied of these lesions is characterized by a recurrent ETV6-NTRK3 gene fusion. However, a notable subset of locally aggressive congenital/infantile soft tissue lesions with similar morphologic features to CIFS, have not to-date, shown evidence of any canonical molecular aberration. We describe 6 patients with mesenchymal tumors composed of infiltrative fibroblastic/myofibroblastic tumor cells and showing a morphologic spectrum of features much analogous to that previously described in CIFS but without ETV6 fusion transcripts. These tumors lacked a uniform immunoprofile, but showed variable expression of CD34, S100, smooth muscle actin, and CD30. All patients first developed a mass in infancy (≤2 months of age). Using next-generation DNA sequencing, TMP3-NTRK1 fusions were identified in 4 cases, an LMNA-NTRK1 fusion in one case, and a variant EML4-NTRK3 fusion in one case. Similar to infantile fibrosarcoma, these tumors were locally aggressive (with local recurrences if incompletely excised) and rarely metastasized (lung metastases in one patient). Proper identification of these tumors including investigation for NTRK family gene rearrangements is essential for diagnostic accuracy, as well as for clinical management decisions. Given the morbidity associated with radical resection of large soft tissue tumors, children with unresectable, recurrent, and/or metastatic disease may benefit from treatment with NTRK targeted therapies.

Infantile myofibromatosis of the iliac bone

INTRODUCTION

Solitary infantile myofibromatosis (IM) of bone is a rare benign osseous tumor of childhood with low rate of recurrence. Well documented within the multicenter form, its solitary intraosseous location is less well described.

CASE REPORT

We present a rare case of intraosseous myofibromatosis arising the iliac bone of a 11-year-old girl, who was operated at 2 months of life for a retroauricular subcutaneous MF with unbalanced translocation t(9;16). She presented with a limping associated to a stiffness of the hip without pain. Imaging disclosed a 4×4×1cm intraosseous, lytic and heterogeneous mass with a soft tissue component on the medial cortical of the left iliac bone. Open biopsy was performed. Histology revealed proliferation of fusiform cells with eosinophil cytoplasm embedded in a myxoid and fibrous stroma without mitotic figures. On immunohistochemistry, cells were positive for actin, PS100, KL1, focally positive for EMA, CD34, P63, rarely CD31, which indicated diagnosis of new localization of IM. Cytogenetic analysis revealed absence of translocation t(9;16), which was found in the first tumor. Subsequent total resection was performed. The patient recovered normal function without recurrence of tumor at 3 years follow-up.

CONCLUSION

To our knowledge, this is the first case of solitary IM of the iliac bone, occurring 12 years after the first localization. Total resection resulted in excellent outcome. However recurrence can happen even long time after the first resection and new localization is possible, as in our case. This suggests close follow-up and clear information about the risk of recurrence.

Extracalvarial Composite Infantile Myofibromatosis: Case Report and Literature Review

Infantile soft tissue tumors of the head are very rare and the majority of them are myofibromas. The authors present the case of a 1-day-old boy with a scalp tumor with several distinct histopathological features including myofibroma, hemangiopericytoma, and fibrosarcoma consistent with the diagnosis of composite infantile myofibromatosis. Genetic testing was negative for trisomy 17, translocation (12; 15), FUS, and ETV6 translocations. Despite the ominous histopathological features, the clinical course was benign. The authors review here available literature concerning current concepts of making the diagnosis of composite infantile myofibromatosis and discuss treatment options.

[Skin tumors in children]

The presence of a congenital or acquired cutaneous lesion is a frequent reason for consultation in pediatric plastic surgery unit. The management of these lesions requires a good knowledge of specific diagnoses in children. This step is sometimes difficult because of the multiplicity of possible diagnosis. Some skin tumors may be the external sign of a general disease or an underlying malformation; those can change the overall prognosis and management and require to be properly identified. The decision of surgical excision depends on various criteria, including diagnosis but also the reconstruction possibilities. The timing of surgical treatment depends on the medical emergency of the tumor resection (benign tumor, spontaneously regressive tumor, risk of degeneration into malignancy), on the cosmetic and psychological impact but also on the growth or learning steps in child life. This article first provides an aid in the diagnosis of the most common or more characteristic skin tumors. The algorithm is principally based on the pigmentation aspect of the tumor. The age and conditions of the surgical management are specified for each type of tumor. Cutaneous hemangiomas and vascular malformations, and congenital cysts and fistulas are not reported in this article.

Pediatric soft tissue tumor pathology: A happy morpho-molecular union

Since its foundation by remarkably talented and insightful individuals, prominently including Pepper Dehner, pediatric soft tissue tumor pathology has developed at an immense rate. The morphologic classification of tumoral entities has extensively been corroborated, but has also evolved with refinement or realignment of these classifications, through accruing molecular data, with many derivative ancillary diagnostic assays now already well-established. Tumors of unclear histogenesis, classically morphologically undifferentiated, are prominent amongst pediatric sarcomas, however, the classes of undifferentiated round- or spindle-cell-tumors-not-otherwise-specified are being dismantled gradually with the identification of their molecular underpinnings. Within recent years, for example, numerous subcategories of 'Ewing-like' round cell sarcoma have emerged. Such advances have provided the basis for novel diagnostic and prognostic sub-classifications. Efforts at defining cell- or lineage-of-origin for several tumor types have produced interesting insights especially for rhabdomyosarcoma. The remarkably early onset of pediatric sarcomas defies the theory necessitating stochastic accumulation of several somatic mutations for cancer development and indeed, these tumors may be remarkably genomically stable, often belying their aggressive nature. Much is coming to light recently regarding the role of epigenetic modifications in the evolution of these sarcomas. Indeed the morphologic features of embryonal tumors generally (not just sarcomas) may be highly reminiscent of arrested differentiation, and given the tight epigenetic regulation of cell fate determination and cell identity maintenance, a theory of epigenetically-driven oncogenesis sits easily with these tumors. The age-delimited distinct biologies of 'pediatric' and adult GIST are intriguing, particularly, the SDH-deficient 'pediatric' form, driven by a metabolic defect, but resulting in epigenetic dysregulation with genome-wide DNA methylation changes. There is little doubt that many of the gaps in our understanding of pediatric sarcoma biology will be filled by a deeper appreciation of the role of dysregulated epigenetics including chromatin biology, perhaps best exemplified in malignant rhabdoid tumor. The field of pediatric soft tissue tumor pathology grows ever more interesting. Importantly though, it must be emphasized, that none of this progress could have occurred, or indeed continue, without the initial step of accurate diagnosis, founded solidly on morphology - thank you Pepper for your unparalleled contributions to this field! The opportunity to be your apprentice for five years has been a bigger and more positive influence than words can express.

Chest Wall Infantile Fibrosarcomas- A Rare Presentation

Infantile fibrosarcoma is rare and represents less than 1 % of all childhood cancers. Commonly, it arises in the limbs followed by the trunk and head and neck. We present a rare case of infantile fibrosarcoma of trunk at two different sites in a newborn with brief review of the relevant literature.

Congenital-infantile fibrosarcoma of the ileocecal region: the first case presentation

Infantile fibrosarcoma is a very rare soft tissue tumor that originates most commonly in the body and extremities. We present a neonate with an infantile fibrosarcoma that originated in the ileocecal region and was detected incidentally without symptoms. This is the first case of fibrosarcoma reported in the ileocecal region.

Primary Pulmonary Fibrosarcoma With Bone Metastasis: a Successful Treatment With Post-Operation Adjuvant Chemotherapy

Introduction:

Pulmonary fibrosarcoma has been an extremely rare tumor in children. Wide surgical resection of infantile fibrosarcoma would be the treatment of choice.

Case Presentation:

Post-operative chemotherapy has shown the benefit in the cases of residual disease after initial surgery and metastatic disease in the literature. We have presented the case of a 70-days old male child with primary infantile fibrosarcoma of the left lung and distant metastasis of skull.

Conclusions:

The aim of this publication was to highlight the role of adjuvant chemotherapy to improve outcome of infantile fibrosarcoma with residual tumor and / or metastatic disease.

Gastrointestinal stromal tumor in a newborn diagnosed in prenatal period: a case report and review of literature

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. Only 1.5% to 2% of all GISTs are observed in children and adolescents. Most of the pediatric cases are between 10 and 18 years of age, with a median age of 13 years. GIST is extremely rare in the newborn period. We could find only 5 reports on the neonatal cases. Herein, we have reported a case with abdominal tumor that was identified by prenatal ultrasonography and magnetic resonance imaging, and diagnosed as GIST on the seventh day of life. We have also reviewed the neonatal GIST cases reported in the English literature.

Emergency surgical treatment of an ulcerative and hemorrhagic congenital/infantile fibrosarcoma of the lower leg: case report and literature review

Fibrosarcomas are rare malignant soft-tissue tumors occurring mostly in infants younger than 1 year of age. Fibrosarcomas can ulcerate and cause various complications, which could threaten a fetus in utero or a child in the early neonatal period. We report a unique case of congenital infantile fibrosarcoma of the lower leg, its treatment and pathology. The large expansive and destructive lesion was not appreciated on routine prenatal ultrasound exams at 20 and 33 weeks gestation. The newborn required immediate emergency surgical intervention after delivery to prevent death by hemorrhagic shock. Initial debulking of the tumor was performed and hemostasis was attained on the day of birth. The child was resuscitated and definitive treatment of the leg was deferred until a pathologic diagnosis was obtained. Given the extent of the fibrosarcoma, the lower leg was not salvageable and the patient received a through-the-knee amputation in the neonatal period. The patient is free of disease at 2 years of age.

Congenital fibrosarcoma and history of prenatal exposure to petroleum derivatives

Congenital fibrosarcoma (CFS) is a rare fibrous tissue malignancy that usually presents in the first few years of life. It is unique among human sarcomas in that it has an excellent prognosis. We describe a temporal clustering of a number of cases of CFS and investigate the possible associated prenatal risk factors. The Pediatric Environmental History, a questionnaire developed in our clinic that is instrumental in determining environmental risk factors for tumor-related disease, was essential in documenting the presence or absence of risk factors considered as human carcinogens. We found a history of exposure to petroleum products in four cases of CFS that occurred at a greater than expected rate in a short time frame-an apparent cancer cluster. We call attention to the possibility that exposure to petroleum products raises the risk of developing CFS. While future studies should focus on systematic investigation of CFS and its underlying mechanisms, this report suggests the need for proactive measures to avoid exposure to solvents and petroleum products during pregnancy.

Recurrent congenital fibrosarcoma with heart metastases

Congenital fibrosarcomas are malignant tumors that arise in soft tissues. In infants this unique tumor does not commonly metastasize, even though there may be local recurrences. We report here a boy who had congenital fibrosarcoma in his right foot, which was completely excised at the age of 3 days. Four months later, a solitary encapsulated metastasis emerged in thoracic chest wall, which was operated. During adjuvant chemotherapy he developed histologically confirmed fibrosarcoma metastases in the heart. After extended treatment with cyclophosphamide/topotecan and gemcitabine/docetaxel, the heart tumors disappeared and he has been in complete remission for 3 years.

Adipose and myxoid tumors of childhood and adolescence

Adipose and myxoid tumors in children are an unusual and challenging group of neoplasms that have some unique aspects in contrast to these tumors in adults. Less than 10% of soft tissue neoplasms in the 1st 2 decades of life have an adipose phenotype and most are benign. The most common are various types of lipoma and lipoblastoma. Liposarcoma in young patients is rare and has a distinctive distribution of histologic subtypes, including classic myxoid liposarcoma, and unusual variants, such as pleomorphic-myxoid liposarcoma. Pathologic examination enhanced by adjunct techniques, such as immunohistochemistry and cytogenetic or molecular genetic studies, is useful for classification of difficult cases. Myxoid tumors can overlap with adipose tumors and are included in this review because of the morphologic similarities and importance of diagnostic accuracy. This article reviews the clinicopathologic features of adipose and myxoid tumors with an emphasis on the unique aspects of these neoplasms in children and adolescents and the differential diagnosis.

Congenital-infantile fibrosarcoma masquerading as sacrococcygeal teratoma

Infantile fibrosarcoma is rare and represents less than 1% of all childhood cancers. Commonly, it arises in the limbs followed by the trunk and head and neck. We report a rare case of infantile fibrosarcoma masquerading as sacrococcygeal teratoma in a newborn. The literature on the subject is also reviewed.

Fibrous hamartoma of infancy: an experience of a single institute

PURPOSE

Fibrous hamartoma (FH) of infancy is a distinctive fibrous growth that most frequently occurs at birth and during the postnatal period. It is important for clinicians and pathologists to recognize this entity to avoid an aggressive approach.

METHODS

We herein describe the clinicopathologic features of 9 FHs diagnosed at a single institution between 1997 and 2010.

RESULTS

There were 7 boys and 2 girls, and the mean age of presentation was 14.7 months. The common locations were the lower back and gluteal region (n = 3) and scrotum (n = 2). They were solitary lesions, and measured 1.0 to 7.0 cm in maximum diameter (mean, 4.9 cm). The excised masses tended to be poorly circumscribed, and consisted of an intimate mixture of firm, gray-white tissue with fat. Histologically, these lesions were composed of 3 components forming a vague, irregular, organoid pattern: well-defined intersecting trabeculae of fibrocollagenous tissue; loosely textured areas of small, rounded, primitive mesenchymal cells; and mature fat. Over a median follow-up of 72 months, no patient showed recurrence.

CONCLUSION

FH should be distinguished from other forms of fibromatosis and malignant tumors because it is benign and usually cured by local excision.

p53+/mdm2- atypical lipomatous tumor/well-differentiated liposarcoma in young children: an early expression of Li-Fraumeni syndrome

The spectrum of lipomatous tumors differs in the adult and pediatric populations, with liposarcoma being rare in children. Nearly 10% of individuals with Li-Fraumeni syndrome develop sarcomas in the first 2 decades of life; however, the frequency of sarcoma types and subtypes in this syndrome is unknown. Two atypical lipomatous tumors/well-differentiated liposarcomas (ALT/WDLS) were identified in the pathology files of our institution in young children from "classical" Li-Fraumeni and Li-Fraumeni variant kindreds with a known germline TP53 mutation (Y220C) in one of the families. The patients were 5 and 6 years of age and the ALT/WDLSs were the first expression of the syndrome. The tumors had a high degree of cellular atypia and differed from sporadic ALT/WDLS by strong nuclear immunoreactivity for p53 and absent mdm2 expression. This is the first report of 2 ALT/WDLSs presenting in children before 10 years of age, both in association with Li-Fraumeni syndrome/variant. ALT/WDLS in a young child should raise the possibility of a cancer predisposition syndrome and, in this setting, the p53(+)/mdm2(-) immunophenotype might be characteristic. Recognition of this lesion and its association is important for early diagnosis and subsequent tumor surveillance in the proband and affected family members.

A rare case of infantile myofibromatosis and review of literature

Infantile myofibromatosis is a rare benign tumor-disease (1/400,000). Four different types have been reported in literature. The most commonly affected body areas are the head, the neck, and the trunk. We would like to present a rare case of a multicentric type with singular visceral involvement and a literature review of all case series with more than five patients. A 9-month-old boy presented with a swelling on the medial side of his proximal left tibia. The lesion which was present since birth, was well palpable, indolent, hard, and mobile in relation to the surrounding tissue. Radiographic films and ultrasound examination presented a pretibial soft-tissue tumor mass with calcifications and two osteolytic lesions with a sclerotic rim. A skeletal survey showed more osteolytic lesions, but the magnetic resonance imaging showed no more soft-tissue lesions. The rapid frozen section biopsy hinted at the diagnosis of histiocytosis X. The definitive histological result 6 days later was infantile myofibromatosis. As therapy, we determined a wait-and-see policy with controls all 3 months. At 20 months follow-up, the boy showed beginning of regression of all lesions. Infantile myofibromatosis is a very rare benign tumor-disease. Radiologically often soft-tissue masses with calcifications and osteolytic lesions with sclerotic rims are described. These findings also can be interpreted as histiocytosis X, which is a potential differential diagnosis. Histopathologically, cells characteristically appear as spindle-shaped fibroblast cells with pale pink cytoplasm and elongated nuclei and the immunophenotype is defined with a positive reaction on smooth-muscle antigen vimentin and the muscle-specific antigen HHF-35. The data of the literature review underline that a wait-and-see-policy should be considered as the first treatment of choice as in most instances the bony lesions regress spontaneously. However, a thorough examination has to be carried out to exclude lesion in other organs like gastro-intestinal or cardio-pulmonary nodular tumor masses. In conclusion, the present case report and the literature review support the notion that infantile myofibromatosis should be considered as a possible differential diagnosis for soft tissue expansions and/or osteolytic lesions in a newborn.

Infantile fibrosarcoma: management based on the European experience

PURPOSE

To retrospectively analyze the clinical features and results of treatment in 56 infants with fibrosarcoma enrolled onto cooperative European protocols between 1979 and 2005 and treated with a combination of surgery and chemotherapy.

PATIENTS AND METHODS

We performed a retrospective case review of infants under the age of 2 years with fibrosarcoma treated between 1979 and 2005 in six European studies. Patients were staged according to the Intergroup Rhabdomyosarcoma Staging System international classification as a function of the type of initial surgery and the extent of disease and were treated with surgery and chemotherapy. Survival was calculated using the Kaplan-Meier method.

RESULTS

Primary tumor site was the limbs in 66% of patients; median tumor diameter was more than 5 cm in 63% of patients; and postoperative staging was as follows: group I, 22%; group II, 27%; group III, 47%; and group IV, 4%. Response rate to chemotherapy was 75%, and the specific response rate to vincristine-dactinomycin was 71%. Local control was obtained in 84% of patients. At the end of follow-up, 45% of survivors had been treated by surgery alone, 6% by chemotherapy alone, 46% by surgery and chemotherapy, and 2% by surgery, chemotherapy, and radiotherapy. The 5-year overall survival (OS) rate was 89%. The 5-year OS and event-free survival rates for localized patients were 89% and 81%, respectively.

CONCLUSION

Although complete resection is rarely feasible at diagnosis, conservative surgery remains the mainstay treatment for infantile fibrosarcoma. An alkylating agent-free and anthracycline-free regimen is usually effective and should be chosen as first-line chemotherapy for inoperable tumors. Overall prognosis is good, but progression or relapse, mainly local, remains possible.

The Spectrum of Pediatric Fibroblastic and Myofibroblastic Tumors

Fibroblastic and myofibroblastic tumors in neonates, infants, and children provide a diagnostic dilemma in surgical pathology due to their relative rarity and similarity in appearances. These tumors may be congenital or occur early during the first years of life or later during the first and second decades of life. The morphologic, immunocytochemical, ultrastructural, cytogenetic, and molecular features of the more "common" pediatric fibroblastic and myofibroblastic tumors are reviewed. In addition, the importance of a multimodal approach to tumor diagnosis is emphasized, with correlation with treatment and outcome differences among these unique fibroblastic and myofibroblastic tumors. The importance of providing an accurate diagnosis with pediatric fibroblastic and myofibroblastic tumors cannot be overstated, because treatment, prognosis, follow-up, and outcome are based on the initial assessment of these fascinating, but oftentimes, perplexing tumors.

[Soft tissue tumors in neonates]

Soft tissue tumors account for approximately 25% of neonatal tumors and are most often benign (more than 2/3 of cases). Vascular tumors are the most frequent benign tumors and infantile hemangioma accounts for 32% of these tumors, affecting 1 out of 200 children at birth. Kaposiform hemangioendothelioma (KH) is a rare vascular tumor with locally aggressive behavior. More than 50% of KH are associated with the Kasabach-Merritt phenomenon, a condition characterized by thrombocytopenia and consumptive coagulopathy. Malignant soft tissue tumors are, after neuroblastoma, the second cause of cancer in neonates. Infantile fibrosarcoma (IF) is a rare tumor that most often affects the extremities of children aged 4 years or younger. A recurrent t(12;15) (p13;q25) rearrangement fusing the ETV6 gene with the NTRK3 neurotrophin-3 receptor gene has been identified in IF. Complete conservative surgical resection is usually curative. Chemotherapy is indicated when initial surgical removal cannot be accomplished without unacceptable morbidity. Prognosis of IF is excellent, with reported overall survival rates ranging from 80 to 100%. Neonatal rhabdomyosarcoma (RMS) is a rare tumor (0.5-1% of RMS). The primary tumor predominantly involves the limbs and the genitourinary tract. Treatment is based on age-adapted chemotherapy and surgery. Prognosis of RMS in children less than 1 year old appears to be comparable with that of older children.

Primary and metastatic lung tumors in the pediatric population: a review and 25-year experience at a large children's hospital

CONTEXT

Primary lung neoplasms are rare in children, but they comprise a broad and interesting spectrum of lesions, some of which are familiar from other tissue sites, and some of which are unique to the pediatric lung.

OBJECTIVE

To determine the relative incidence of primary and metastatic lung tumors in children and adolescents through a single-institution case series, to compare these data to reports in the medical literature, to discuss the clinical and pathologic features of primary tumors of the tracheobronchial tree and lung parenchyma in children, and to provide recommendations for handling pediatric lung cysts and tumors.

DATA SOURCES

A 25-year single institutional experience with pediatric lung tumors, based on surgical biopsies and resections at Texas Children's Hospital from June 1982 to May 2007, an additional 40 lung tumors referred in consultation, and a review of the medical literature.

CONCLUSIONS

A total of 204 pediatric lung tumors were diagnosed at our institution, including 20 primary benign lesions (9.8%), 14 primary malignant lesions (6.9%), and 170 secondary lung lesions (83.3%). The ratio of primary benign to primary malignant to secondary malignant neoplasms is 1.4:1:11.6. The common types of lung cancer in adults are exceptional occurrences in the pediatric population. The most common primary lung malignancies in children are pleuropulmonary blastoma and carcinoid tumor. Other primary pediatric lung tumors include congenital peribronchial myofibroblastic tumor and other myofibroblastic lesions, sarcomas, carcinoma, and mesothelioma. Children with primary or acquired immunodeficiency are at risk for Epstein-Barr virus-related smooth muscle tumors, lymphoma, and lymphoproliferative disorders. Metastatic lung tumors are relatively common in children and also comprise a spectrum of neoplasia distinct from the adult population.

Primary colonic congenital infantile fibrosarcoma presenting as meconium peritonitis

Congenital infantile fibrosarcoma is a rare soft tissue malignancy that occurs in both axial and extremity locations. We report a case of this tumor arising from the left colon in a newborn presenting with an intrauterine perforation and meconium peritonitis.

Cervical lipoblastoma: Case report, review of literature, and genetic analysis

BACKGROUND

Lipoblastoma is a rare, benign tumor of infants and children, usually occurring in the extremities and trunk, with only a few cases reported in the neck.

METHODS

We describe the case of an infant with a rapidly enlarging, painless neck mass. MRI revealed a 4-cm-diameter mass deep to the paraspinal muscles, in close proximity to the C2 vertebral foramen. Review of literature, diagnostic methods, and genetics of lipomatous tumors are discussed.

RESULTS

Complete surgical excision via a posterior cervical approach demonstrated irregular lobules of immature fat cells separated by a loose, myxoid connective tissue. Histology and genetic analysis confirmed the diagnosis of lipoblastoma.

CONCLUSION

Cervical lipoblastoma is rare, and typically presents as an asymptomatic, painless mass, rarely causing airway obstruction or nerve compression. MRI can be helpful in identifying the lipomatous nature of the mass, but the findings can be inconsistent due to variable maturity of fat cells and the mesenchymal content of the tumor. Chromosomal analysis is useful in differentiating lipoblastoma from liposarcoma. Recommended treatment is complete surgical excision.

Benign fibrous histiocytoma with osteoclast-like giant cells in an infant

Benign fibrous histiocytoma is a common soft tissue tumor that usually occurs in adults and is relatively rare in childhood. This report describes a 7-month-old Caucasian boy with an enlarging firm congenital nodule on his occipital scalp. Histologic analysis revealed a benign fibrous histiocytoma with osteoclast-like giant cells. Benign fibrous histiocytoma with osteoclast-like giant cells is a rare histologic variant.

Plaque-like myofibroblastic tumor of infancy

Fibrohistiocytic neoplasms are relatively uncommon in infancy and childhood. We report an unusual spindle cell tumor occurring in two infants within the first 3 months of life. These tumors histologically resembled dermatofibromas, but the young age of onset, large size, and plaque-like morphology were distinctly different from those of dermatofibromas. The features of these neoplasms are discussed and the differential of other spindle cell tumors of infancy is reviewed.

Postauricular congenital alveolar rhabdomyosarcoma- a case report of an unusual entity

Background

Congenital alveolar rhabdomyosarcoma is an extremely uncommon and invariably fatal tumor with the current therapy. Less than 25% of patients present with evidence of cutaneous metastasis.

Case presentation

We report a case of congenital alveolar rhabdomyosarcoma in an 18-month-old male who presented with a progressively increasing mass lesion in the left post-auricular region since birth. Radiological examination did not show any intracranial involvement of the mass lesion. Upon resecting the mass that was 10-cm in largest dimension, the gross, microscopic, and ultrastructural findings were consistent with congenital alveolar rhabdomyosarcoma.

Conclusion

The suspicion of alveolar subtype on histological grounds and proper evaluation of this tumor by immunostain and ultrastuctural examination is necessary. In the Medline literature search, there is no report of large congenital alveolar rhabdomyosarcoma in the post-auricle region.

[Infantile hemangiomas: differential diagnosis and associated anomalies]

Infantile hemangiomas are frequent benign vascular tumors that are often easily recognized. However, the diagnosis between infantile hemangiomas and other vascular tumors, whether benign or malignant, may be difficult. This chapter describes the different clinical presentations of hemangiomas and details the investigations that are needed to confirm the nature of the lesion and to diagnose the potentially associated anomalies. Knowledge on differential diagnosis enables clinicians to detect hemangiomas that can lead to complications and that necessitate a multidisciplinary approach.

Lipoblastoma and lipoblastomatosis

We report two cases of lipoblastoma of the buttock in a 10-month-old boy and a 20-month-old girl, the first with rearrangement of chromosome 8 and the second without cytogenetic abnormality, and one case of lipoblastomatosis of a leg in a 6-month-old boy with a normal karyotype but with a rearrangement of the PLAG1 gene. Lipoblastoma and lipoblastomatosis are two different presentation of the same rare benign soft tissue mesenchymal tumour arising from fetal white fat and occurring almost exclusively in young children under 3 years. These neoplasms have no malignant potential but may recur in cases of incomplete resection. Histological diagnosis sometimes used to be difficult because of the close resemblance of the lesion with myxoïd liposarcoma. Nowadays, cytogenetic analysis may contribute to the diagnosis by showing abnormalities of the long arm of chromosome 8, leading to rearrangement of the PLAG1 gene. Actual advances in cytogenetic molecular analysis may aid in accurate diagnosis.