Fibrous tumors and tumor-like lesions of childhood: diagnosis, differential diagnosis, and prognosis

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.

Miofibromatose infantil: relato de uma rara doença

A miofibromatose infantil é uma rara doença que tem várias formas de apresentação. Habitualmente, manifesta-se com nódulos subcutâneos, que podem ou não estar associados à presença de nódulos viscerais. Deve-se estar apto a fazer o diagnóstico por meio do exame físico e de imagem, que evidenciarão o padrão das lesões para estadiar/classificar a doença. O tratamento ainda é controverso.

Platelet-derived growth factor receptors and ligands are up-regulated in paediatric fibromatoses

AIMS

Platelet-derived growth factors (PDGF) and their receptors (PDGFR) play an essential role in pathways involved in the regulation of cell proliferation, growth and function. Overexpression of PDGF/R is reported in a wide range of solid tumours. The aim was to determine levels of PDGF/R expression in paediatric fibromatoses and myofibromatosis.

METHODS AND RESULTS

Quantitative real-time polymerase chain reaction was used to examine the expression level of alpha and beta isoforms of PDGF/R in 17 fibromatoses, four myofibromatoses and three dermatofibrosarcoma protuberans (DFSP) in children. Fifteen of 17 (88%) fibromatoses and all myofibromatoses and DFSPs demonstrated increased expression of PDGFalpha and beta compared with a panel of normal tissues. In terms of the cognate receptors, 13/17 (76%) fibromatoses demonstrated increased expression for PDGFRalpha and Rbeta, whereas 3/4 myofibromatoses demonstrated increased expression of PDGFRalpha and all four had increased PDGFRbeta expression. All DFSPs were associated with increased expression of both PDGFRalpha and PDGFRbeta compared with normal control tissues.

CONCLUSIONS

Increased expression of PDGF/Ralphabeta may play an important role in the mechanism of growth of these paediatric fibromatous lesions and warrants further investigation, since novel therapeutic interventions could potentially be developed in the light of the expression patterns.

Response of progressive fibromatosis to therapy with liposomal doxorubicin

BACKGROUND

Patients with fibromatosis not amenable to surgery may suffer from high morbidity. Various chemotherapeutic regimens have been tried in these patients with limited success. Here, we report on the successful use of pegylated liposomal doxorubicin in the treatment of 4 patients with unresectable fibromatosis in unfavorable localizations.

PATIENTS AND METHODS

3 children and 1 adult with progressive fibromatosis were treated with 3-weekly cycles of chemotherapy with liposomal doxorubicin (dose range 20-50 mg/m2 per day every 21 days). Tumors were located at the nasal cavity, fossa infratemporalis, oral cavity, abdomen, and fossa supraclavicularis and were unresectable. 3 of the 4 patients had been heavily pretreated with various chemotherapeutic agents. Objective tumor response was monitored by magnetic resonance imaging and possible cardiotoxicity by echocardiography at regular intervals.

RESULTS

A tumor response was obtained in all 4 patients. All patients showed normal cardiac function after completion of chemotherapy as evaluated by left ventricular shortening fraction. Severe neutropenia was not observed.

CONCLUSION

Pegylated liposomal doxorubicin is a therapeutic option in patients with progressive unresectable fibromatosis in unfavorable localizations.

Proliférations fibroblastiques et myofibroblastiques de l’enfance et de l’adolescence

Fibroblastic-myofibroblastic proliferations of childhood and adolescents form a clinical and morphologic spectrum from benign reactive processes and pseudosarcomas, to fibromatoses, to various types of sarcoma. The diagnosis is challenging because of clinical and morphologic similarities, lack of specific immunohistochemical markers for different types of fibroblastic-myofibroblastic tumors, and limited molecular genetic information. Careful attention to clinical, macroscopic, and histopathologic features permits classification in most cases. This review focuses on the pathologic features of fibroblastic-myofibroblastic tumors with a predilection for children and adolescents.

Cytologic diagnosis of fibrous hamartoma of infancy: a case report

Fibrous hamartoma of infancy (FHI) is a rare benign lesion in the first 2 years of life with a distinctive histomorphologic appearance. There were only two descriptions of this entity in the cytology literature. In this article, the detailed clinical profile and cytologic features of a case of FHI is described in a 6-month-old male infant who presented with a nodular mass in the anterior axillary fold. Fine-needle aspiration (FNA) cytology smears showed an admixture of adipose tissue fragments, discretely lying, and clusters of fibroblastic cells in association with myxoid and collagenous matrix. FNA cytology features along with proper clinical history, radiological findings, family history, and location of the lesion may be helpful to suggest the probable preoperative diagnosis of this lesion.

Fibrous umbilical polyp: a distinct fasciitis-like proliferation of early childhood with a marked male predominance

Benign fibrous lesions of the umbilicus have not been previously studied in a formal series. Clinical and pathologic findings were reviewed in all patients under age 19 with lesions resected from the umbilical region at Children's Hospital (Boston, MA, USA) during an 8-year period. Fourteen lesions were characterized by a well-circumscribed dome-shaped or pedunculated dermal proliferation of moderately cellular fibrous tissue without significant inflammation. Fibroblastic cells were plump to elongate with abundant pale pink cytoplasm. In a subset of lesions, some cells showed atypia or ganglion cell-like morphology. Collagen ranged from sparse to long narrow bundles. Vascularity was sparse and the lesions were nonencapsulated. Loss of rete ridges and basket-weave hyperkeratosis was common in the overlying epidermis. Immunostaining showed focal staining for muscle-specific actin and desmin in a subset of cases and no staining for cytokeratin, epithelial membrane antigen, CD34, or S-100. Age ranged from 3 to 18 months (mean 9 months, median 8 months). Thirteen (93%) patients were boys. Recurrence was not observed. In conclusion, the "fibrous umbilical polyp" is a distinctive lesion of early childhood with an uncertain pathogenesis. It shows a marked predilection for boys, is not rare, and appears to represent a clinicopathologic entity. Perhaps the umbilicus, a midline defect that is normally filled by dense scar tissue after birth, contains unique fibrogenic factors responsible for the development of this distinct lesion.

Generalized infantile myofibromatosis in a patient with Turner's syndrome: a trial of interferon-alpha

A patient with Turner's syndrome was found to have generalized infantile myofibromatosis with visceral involvement at birth. The infant was treated with interferon-alpha because of the size of the lesions. Two months after treatment, the lesions appeared to have decreased in size and showed evidence of maturation with decreased apoptosis on histologic examination. Interferon-alpha treatment might induce regression of myofibromatosis.