Malignant fibrous histiocytomas in children

Pleomorphic spindle cell sarcoma (PSCS) formerly known as malignant fibrous histiocytoma (MFH): a complex malignant soft-tissue tumor

A presentation defining the nature, characteristics, causation, treatment and outcome of patients with lesions formerly known as malignant fibrous histiocytoma and now as pleomorphic spindle cell sarcoma is clearly a very difficult subject. Many authors do not believe that the tumor exists and instead describe them as forms of fibrosarcomas, fibromyxoid lesions, dedifferentiated chondrosarcomas or even leiomyosarcomas. The reasons for this confusion are presumably related to the fact that the malignant pleomorphic spindle cell sarcoma does not seem to be a distinct type of lesion with specific histologic and genetic characteristics. Instead, the tumor has at least four separate histologic variations and no specific gene signature and in fact does not seem to be either familial or ethnic in presentation. In view of the fact that the tumor was traditionally the most frequently encountered malignant soft-tissue neoplasm, the world of orthopedic oncology is clearly distressed by the problems that these patients have and is joined by the radiation oncologists and chemotherapists in seeking new solutions.

Fibrohistiocytic tumors and related neoplasms in children and adolescents

Fibrohistiocytic tumors (FHTs) in children and adolescents range from the benign fibrous histiocytoma, or dermatofibroma, to a variety of intermediate and malignant neoplasms, such as dermatofibrosarcoma protruberans and high-grade undifferentiated pleomorphic sarcoma (malignant fibrous histiocytoma). Those tumors as a group are comprised of fibroblasts, myofibroblasts, and histiocytes-dendritic cells with a variably prominent inflammatory infiltrate consisting of lymphocytes and eosinophils. Dendritic cells are also a major constituent of another group of neoplasms that include Langerhans cell histiocytosis, follicular and interdigitating cell sarcomas, and juvenile xanthogranuloma. These latter tumors are considered in this discussion for the sake of differential diagnosis and their possible histogenetic relationship to FHTs. Recent studies have suggested that the relationship between the fibroblast and histiocyte in the FHTs may reflect the intrinsic capacity to transdifferentiate from one to the other morphologic and functional state. The so-called "facultative fibroblast," as a cell with fibroblastic and histiocytic properties, was discussed in the context of the fibrous xanthoma 50 years ago. Possibly the entire histogenetic concept of FHTs should be reconsidered in light of current studies.

Undifferentiated high-grade pleomorphic sarcomas in children: a clinicopathologic study of 10 cases and review of literature

Undifferentiated high-grade pleomorphic sarcoma (UHGPS) is a sarcoma of debated nosology affecting adults, with rare cases reported in children. In order to investigate the clinicopathologic and prognostic features of pediatric UHGPS, 10 cases of UHGPS occurring before 18 years (mean age, 8.9 years) were analyzed. All were localized at diagnosis (head, 4; lower extremities, 4; trunk, 2), with a mean diameter of 4.5 cm. Mean follow-up was 6 years. Six patients were in complete remission, 1 after a relapse; 2 died of metastatic disease; 1 was alive with metastasis. Histologically, 8 tumors showed spindle cells with a focal or diffuse storiform pattern; 2 tumors had scattered aggregates of epithelioid cells. Two tumors displayed a prominent epithelioid component. Cellular pleomorphism, high mitotic rate with atypical mitoses, were found in all tumors; necrosis in 6 and vascular invasion in 2. CD68 and desmin were positive in 2 cases each, smooth muscle actin in 4, and S100 in 1. Five tumors in 1st and 1 in 2nd complete remission were superficial; 1 showed a spindle cell morphology with epithelioid foci, 3 had necrosis; 5 were grade 3; and 1 was grade 2. Three metastatic tumors (2 in the dura, 1 in the leg) displayed either a prominent epithelioid morphology (2) or scattered aggregates of epithelioid cells (1), with a myxoid background in 1. All were grade 3 and showed foci of necrosis. In summary, UHGPS is rare in children and frequently located in the head. A more favorable outcome is associated with superficial location. Foci of epithelioid cell may portend an aggressive behavior.

Malignant fibrous histiocytoma and other fibrohistiocytic tumors in pediatric patients: the St. Jude Children's Research Hospital experience

BACKGROUND

Malignant fibrous histiocytoma (MFH) is a controversial entity. In the current study, the authors reviewed their institutional experience with these tumors to characterize their clinical features in pediatric patients and assess the impact of surgical resection on outcome.

METHODS

The records of the 28 patients who were diagnosed with MFH or MFH variants of soft tissue between January 1971 and December 2000 were reviewed and the tumors were reclassified according to the World Health Organization guidelines.

RESULTS

Seventeen patients had MFH; 10 patients had angiomatoid fibrous histiocytoma (FH), and 1 patient had a plexiform fibrohistiocytic tumor. The median age of patients at the time of diagnosis was 7.3 years. The most common primary tumor site was the extremity (n = 14). Metastatic disease (to the lung) was present in only three patients, each of whom had MFH. Of the 17 MFH tumors, 13 were high grade, 8 were invasive, and 6 measured > 5 cm. All angiomatoid FH tumors and the plexiform fibrohistiocytic tumor were noninvasive, and 10 measured < or = 5 cm. Surgical treatment was comprised of wide local excision with clear margins (n = 18), amputation (n = 3), excision with positive or indeterminate surgical margins (n = 4), partial resection (n = 2), or biopsy only (n = 1). Primary reexcision was performed for 21 patients. The 5-year survival and event-free survival (EFS) estimates for patients with MFH were 76.5% +/- 11.2% and 70.6% +/- 12.1%, respectively; the 5-year survival and EFS estimates were 100% +/- 0% for patients with angiomatoid FH or plexiform fibrohistiocytic tumor. Compared with partial resection or excision, wide local excision or amputation was found to have a positive impact on the probability of EFS in patients with localized disease (P = 0.008). All four patients with metastatic or unresectable MFH had died by the time of last follow-up.

CONCLUSIONS

MFH should be distinguished from angiomatoid FH and plexiform fibrohistiocytic tumors, both of which are less aggressive. Wide local excision is the treatment of choice, regardless of the histology or grade of the tumor. Patients with metastatic or unresectable MFH appear to have a poor outcome and would benefit from more effective therapies.

Nonrhabdomyosarcoma soft tissue sarcomas in children. The Mayo Clinic experience

Eighty-six children to 18 years of age were treated for nonrhabdomyosarcoma soft tissue sarcomas of the trunk and extremities. Synovial sarcoma (31), fibrosarcoma (13), malignant fibrous histiocytoma (11), epithelioid sarcoma (10), and clear cell sarcoma (7) were the most common diagnoses. Four patients presented with metastatic disease. A high percentage of patients presented after biopsy by the referring physician, although this could not be shown to affect outcome. Patients were treated with wide removal of the tumor when possible, with judicious use of adjuvant radiation, or with chemotherapy in selected cases. Mean followup was 11 years. Five- and 10-year survival was 92% and 84%, respectively. Tumors larger than 5 cm were associated with a worse prognosis. When compared with published data in adults, the prognosis of primary, localized nonrhabdomyosarcoma soft tissue sarcomas in children appears to be more favorable.

Primary malignant fibrous histiocytoma of the lung in a child: a case report and review of literature

Malignant fibrous histiocytoma (MFH), an aggressive high-grade soft tissue sarcoma, usually occurs in the elderly during the fifth to seventh decade of life. It commonly arises in the retroperitoneum, extremities, and head and neck region. Primary pulmonary MFH is extremely rare and is frequently fatal. We present the youngest known case, a 9-year-old boy with a primary left lung grade II inflammatory MFH, stage II. He underwent a left upper lobectomy for tumor resection. After completing radiation therapy, he was started on vincristine, actinomycin D, and cyclophosphamide alternating with vincristine, doxorubicin, and cyclophosphamide every 3 weeks. After five such cycles, he had a histologically proven local recurrence. He then received chemotherapy consisting of ifosfamide (2 g/m2) and etoposide (VP-16) (100 mg/m2) given daily for 3 days every 3 weeks. The patient attained complete remission (CR) after five such cycles and completed treatment without any major complications. He received a total of 16 courses and is continuing in CR 36 months off treatment. Ifosfamide and etoposide (VP-16), known for their usefulness in treatment of adult soft tissue sarcomas, can be used as salvage chemotherapy for patients with MFH who fail the front-line conventional chemotherapy.

Malignant fibrous histiocytoma in children

Because malignant fibrous histiocytoma (MFH) rarely occurs in children, the natural history of this tumor and prognostic factors predictive of outcome have not been well described. The charts of all pediatric patients with MFH seen at M.D. Anderson Cancer Center were reviewed with respect presentation, treatment, and outcome, in an attempt to determine prognostic factors that are predictive of survival. Forty-four pediatric patients were identified. Extremities were the most common tumor site (31 of 44 patients). Five patients presented with angiomatoid histology subtype; all subsequently survived. The estimated 5-year survival rate was 85% for clinical group I patients, 87% for clinical group II, 53% for clinical group III, and 0% for clinical group IV. The estimated 5-year survival rate was 95% for patients with tumors of less than 5 cm in diameter and 45% for those with larger tumors. Overall, the estimated 5-year survival rate was 71%. Significant prognostic factors found to affect survival (by univariate analysis) were clinical group, tumor size, and recurrence. Gender and race were not significant predictors. The use of chemotherapy and radiation was not found to improve the chance of survival, but this most likely reflected the more frequent use of adjuvant therapy in patients with unresectable or high-grade tumors. Although adequate surgical resection continues to be the most effective treatment, investigation of adjuvant chemotherapy and radiation therapy on protocol is warranted.

Adjuvant chemotherapy for treatment of unresectable and metastatic angiomatoid malignant fibrous histiocytoma

Angiomatoid malignant fibrous histiocytoma (AMFH) is a low grade soft tissue sarcoma usually treated with surgery alone. Only one adult patient has been treated with systemic chemotherapy. The authors report a case of unresectable, metastatic AMFH treated initially with vincristine, doxorubicin, dactinomycin, and cyclophosphamide. A complete response at the metastatic site and a marked reduction in the size of the primary tumor allowed complete surgical excision 7 months after treatment was initiated. The patient remains disease free 19 months after being diagnosed. It was concluded that systemic chemotherapy may be effective in patients with AMFH.

Malignant fibrous histiocytoma of primary omental origin in an infant

A case of malignant fibrous histiocytoma occurring in an infant is presented. The primary location of the tumor was in the omentum. Sonography showed huge, lobulated echogenic masses with cystic areas. CT demonstrated heterogeneously enhancing masses with central cystic and necrotic areas. This very unusual occurrence of a tumor in infancy with an intraabdominal location is described and the radiographic imaging is presented.

Malignant fibrous histiocytoma of the brain in a six-year-old girl

We have prepared karyotypes from a malignant fibrous histiocytoma (MFH) of the brain of a 6-year-old girl. Sporadic cases of MFH in the central nervous system have been reported. However, to our knowledge, this is the first central nervous system tumor to be subjected to cytogenetic analysis. The tumor demonstrated a complex karyotype, with a variety of numerical and structural abnormalities. Although no specific cytogenetic abnormality was observed, the karyotype of this case was similar to those reported for adult MFH of soft tissues.

Monomorphous histiocytoma in a child. Report of a case with ultrastructural features suggestive of dendritic cell differentiation

The authors describe a rapidly growing soft tissue tumor of predominantly histiocytic composition in an 8-year-old child. The tumor cells were identified as elements of the mononuclear phagocyte system by histologic, histochemical, immunologic, and electron microscopic study. Despite the presence of a minor fibroblastic component, the tumor did not conform to established criteria for a diagnosis of malignant fibrous histiocytoma. Formation of frequent desmosome-like intercellular junctions raised the possibility of dendritic reticulum cell differentiation, since the latter cells seem to be the only elements of the mononuclear phagocyte system that display such specialized cell junctions. The results of immunostaining were discrepant with those reported for normal dendritic reticulum cells, but the currently available information makes it doubtful that the entire neoplastic spectrum of dendritic cell differentiation can currently be diagnosed in surgical pathology.

Malignant fibrous histiocytoma in the abdominal soft tissues of a child: a case report

An 18-month-old female presented with an abdominal tumor mass which on morphological, immunohistological and ultrastructural examination was found to be a malignant fibrous histiocytoma. This soft tissue sarcoma is rarely encountered in childhood. Treatment in this case consisted of surgical tumor debulking with pre- and post-operative chemotherapy. The child is well and free of detectable tumor at 23 months after diagnosis.

Soft tissue sarcomas

Soft tissue sarcomas in infants and children differ from those in adults in clinical presentation, histology, and response to therapy. For rhabdomyosarcoma, the most common sarcoma in children, each primary site has special characteristics that affect both treatment programs and survival rates. Some results are so good, from the standpoint of survival data, that studies are now in progress to evaluate means of reducing treatment morbidity. Other ongoing studies focus on improved protocols for metastatic or recurrent rhabdomyosarcoma. Results thus far in the IRS trials have proven the value of cooperative clinical trials in the management of patients with this disease.

Malignant fibrous histiocytoma in childhood: a report of two cases and review of the literature

Malignant fibrous histiocytoma (MFH) is a tumor of late adult life not often recognized as occurring in children. Our search of the English literature produced only 27 well-documented examples occurring in the soft tissues, to which we here add 2 additional cases. Both of our cases displayed the classical storiform-pleomorphic histologic pattern typical of such tumors in adults, and both pursued a malignant and rapidly fatal course. Previous reports of this tumor in children are reviewed, and the differential diagnostic considerations briefly discussed. Overall, the clinical features of MFH in children are similar to those reported in adults, and surgical removal remains the key element of successful therapy.

Computed tomography of primary malignant fibrohistiocytoma of the lung

A case of malignant fibrous histiocytoma of the lung is reported in pediatric patient-uncommon location as well as age group.

Malignant fibrous histiocytoma of soft tissue in childhood

Seven children aged 6 months to 11 years with malignant fibrous histiocytoma, a type of sarcoma of soft tissues, have been treated at the Children's Hospital of Philadelphia from January 1975 through July 1983. The primary tumor arose in the head and neck region in three patients, the chest wall in two patients and the pelvis or buttock in one patient each. Operative management consisted of complete tumor removal in the two patients with chest wall tumors, and biopsy only in the remaining five children. Afterward, all seven patients were treated with a multiple-agent chemotherapy program consisting of vincristine, dactinomycin, and cyclophosphamide for two years, with or without Adriamycin (doxorubicin). The five patients with residual tumor also received radiation therapy (RT) in doses of 1500 to 5500 rad. The two children with localized, completely excised sarcoma are continuously free of tumor at 1.4 and 9 years after initiation of treatment. Of the five with residual sarcoma, three had a complete response to radiation and chemotherapy, and two of them are free of recurrence at 4 and 5 years, respectively. In the three remaining children, the tumor spread regionally into the central nervous system or distantly into the lungs, subcutaneous tissues, and liver. Childhood malignant fibrous histiocytoma of soft tissue appears to be similar to childhood rhabdomyosarcoma in its modes of spread and response to management. Operative removal is the key to successful therapy. The roles of multiple-agent chemotherapy and RT remain to be defined. Adriamycin appears to be the most promising single agent. In the absence of concrete data, it seems prudent to follow the same guidelines for irradiation as those used for other soft tissue sarcomas of childhood.