Malignant fibrous histiocytoma of the face: report of a case.

BACKGROUND: Soft tissue sarcomas in the head and neck region are rare and often present a difficult differential diagnosis. The aim of our presentation is to point out the complexity of the diagnosis, treatment and follow up. CASE PRESENTATION: An eighty-seven year old female patient was referred to our unit with a fast growing brownish lump on the face. Four months beforehand, a benign fibrous histiocytoma (BFH) had been removed from the same location by excision biopsy with wide tumour-free resection margins. Excision biopsy of the recurrent lesion revealed a malignant fibrous histiocytoma (MFH). Radical tumour resection was completed by extended parotidectomy and neck dissection; the skin defect was covered by a regional bi-lobed flap. No adjuvant radio- or chemotherapy was administered. Full functional and cosmetic recovery was achieved; follow-up has been uneventful more than two years postoperatively. DISCUSSION: Malignant transformation of BFH is extremely rare and if so, extended radical surgery may give a fair chance for a favourable outcome even in patients with advanced age.

Melanotic neuroectodermal tumor of infancy: systematic review of the literature and presentation of a case.

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, distinctive neoplasm of early infancy with rapid expansile growth and a high rate of recurrences. Most commonly the lesion affects the maxilla of infants during the first year of life, but it may also occur in the mandible, skull, brain, epididymis, and other rare locations. The origin of the tumor is the neural crest. The expansive, destructive, and rapid growth of MNTI and its effects on the surrounding tissues are the most obvious clinical features. Microscopically, large polygonal epithelioid cells resembling melanocytes, with variable deposits of melanin, and smaller neuroblast-like round cells characterize MNTI. Malignant transformation may occur. Since the first description in 1918, only 215 cases were reported up to the last extensive review in 1992. The present review supplements another 140 published cases of MNTI up to 2004, including an original case report. Clinical features, treatment alternatives, and follow-up are discussed.

Biological and biomechanical evaluation of interface reaction at conical screw-type implants.

BACKGROUND: Initial stability of the implant is, in effect, one of the fundamental criteria for obtaining long-term osseointegration. Achieving implant stability depends on the implant-bone relation, the surgical technique and on the microscopic and macroscopic morphology of the implant used. A newly designed parabolic screw-type dental implant system was tested in vivo for early stages of interface reaction at the implant surface. METHODS: A total of 40 implants were placed into the cranial and caudal part of the tibia in eight male Göttinger minipigs. Resonance frequency measurements (RFM) were made on each implant at the time of fixture placement, 7 days and 28 days thereafter in all animals. Block biopsies were harvested 7 and 28 days (four animals each) following surgery. Biomechanical testing, removable torque tests (RTV), resonance frequency analysis; histological and histomorphometric analysis as well as ultrastructural investigations (scanning electron microscopy (SEM)) were performed. RESULTS: Implant stability in respect to the measured RTV and RFM-levels were found to be high after 7 days of implants osseointegration and remained at this level during the experimented course. Additionally, RFM level demonstrated no alteration towards baseline levels during the osseointegration. No significant increase or decrease in the mean RFM (6029 Hz; 6256 Hz and 5885 Hz after 0-, 7- and 28 days) were observed. The removal torque values show after 7 and 28 days no significant difference. SEM analysis demonstrated a direct bone to implant contact over the whole implant surface. The bone-to-implant contact ratio increased from 35.8 +/- 7.2% to 46.3 +/- 17.7% over time (p = 0,146). CONCLUSION: The results of this study indicate primary stability of implants which osseointegrated with an intimate bone contact over the whole length of the implant.

Agressive fibromatosis involving the mandible--case report and review of the literature.

BACKGROUND: Aggressive fibromatosis (AF) involving the mandible is rare, and surgery is often complicated by a high recurrence rate. CASE REPORT: A 4-year-old boy was referred because of a fast growing painless mass which involved the entire left angle of the mandible. Excisional biopsy revealed AF, and local excision of the tumor was performed. Six months after surgery a recurrence was detected. The tumor was determined to be unresectable and the boy was treated with low-dose chemotherapy including methotrexate and vinblastine for 1 year. With combined chemotherapy and surgical debulking, mutilating surgical resection will be delayed as long as possible or until completion of facial growth. CONCLUSION: According to the literature, surgery is the most common treatment of AF in the head and neck region. However, particularly in children, alternative modes of therapy must be considered because of the high recurrence rate and to avoid mutilating operations.