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Clinicopathologic features, treatment, and prognosis of postirradiation osteosarcoma in patients with nasopharyngeal cancer.

OBJECTIVES: Postirradiation osteosarcoma (PIOS) arising after radiation of nasopharyngeal cancer (NPC) is rare and seldom reported. In this article, we report its clinicopathologic features, outcome, and prognostic factors. STUDY DESIGN: Retrospective cohort study. METHODS: Fifteen patients with NPC were determined to have PIOS after reviewing 426 patients with osteogenic sarcomas. Their clinical records, image and pathologic slides, and follow-up data after treatment were collected to perform analysis. RESULTS: The incidence rate of PIOS in NPC was approximately 0.037% (15/40,719), which occupied approximately 3.5% (15/426) among all kinds of osteogenic sarcomas. The latent time of PIOS after irradiation for NPC ranged from 4 to 27 years, with a mean of 13.3 years. The location where PIOS arose included 33.3% (5/15) from maxilla, 46.7% (7/15) from mandible, and 20% (3/15) from a mixture of nasal cavity and paranasal sinuses. Radiologically, soft tissue mass, bone destruction, and tumor new bone formation were the main characteristics. Pathologic subtypes included 53.3% (8/15) of fibroblastic osteosarcoma, 33.3% (5/15) of chondroblastic osteosarcoma, and 13.3% (2/15) of mixed type osteosarcoma. Of 15 patients with PIOS, 12 patients were treated with curative intent, and the remaining 3 patients with palliative intent. For 12 patients who had undertaken ablative surgery, 1 patient had residual tumor, and 6 patients had tumor recurrence. The survival time after treatment for all patients ranged from 7 to 41 months, with a mean of 18 months. Kaplan-Meier estimates of 1 year and 2 year survival rates were 60% and 24%, respectively. Statistical analysis showed that sex and tumor bone formation are significant prognostic factors. CONCLUSIONS: PIOS in NPC is a highly malignant disease with poorer prognosis than in other sites. Surgery combined with pre- and postoperative chemotherapy might be an effective way to improve survival.

Adolescent↗

Treatment of squamous cell carcinoma of the retromolar trigone.

OBJECTIVES: Retromolar trigone (RMT) squamous cell carcinoma is uncommon but notorious for poor prognosis. We reviewed our experience in the management of RMT cancer to determine survival rates and to identify prognostic factors. METHODS: Fifty patients with RMT squamous cell carcinoma were treated with surgery and/or radiation or chemoradiation therapy between July 1993 and June 2004 at Chang Gung Memorial Hospital, Taiwan. Patients were followed up for 3 to 106 months (mean, 36 months). There were 6 stage I, 13 stage II, 4 stage II, and 27 stage N patients. RESULTS: The 5-year actuarial survival rate for stage I to N and all stages were 100%, 74.1%, 75%, 43.6%, and 60.6%, respectively. Seventeen (34%) patients had maxilla bone (11 [22%]) or mandible bone (9 [18%]) invasion. Eleven (22%) patients had masticator space involvement. Cervical metastasis rate was 26%. Multivariate analysis revealed that masticator space involvement, neck recurrence, and cervical metastasis were poor prognosticators of survival by order. The maxilla bone was more apt to be involved by RMT cancer than the mandible. Patients with masticator space involvement had a 5-year actuarial survival rate of 22.5% and the mean survival time was only 37.8 months. CONCLUSIONS: RMT squamous cell carcinomas are aggressive tumors. The maxilla is more apt to be involved than the mandible. Deep infiltration of the masticator space and invasion of the maxilla and mandible worsen the prognosis.

Adult↗

Quantitative analysis of histological parameters in giant cell lesions of the jaws and long bones.

Stereological techniques have been used to compare histological parameters of the giant cell component in 10 giant cell tumours of long bones, 10 central giant cell granulomas of the jaws and 10 peripheral giant cell granulomas of the jaws. The giant cell parameters investigated were: mean profile diameter, mean diameter, mean profile axial ratio, volume-to-surface ratios, nuclear numerical density, profile area and cell volume. Serial sections were cut at 4 micron from routinely fixed, paraffin-embedded specimens of each case and two sections, separated by 100 micron, were stained with haematoxylin and eosin. Random fields were photographed until at least 25 giant cell profiles had been recorded from each of the two sections of each lesion. The processed film was projected for point and intersect counting, the entire procedure ensuring double-blind assessment of the cases under investigation. In general there was no significant difference for any of the parameters between the giant cells of central and peripheral jaw lesions. There was a significant difference, however, between the giant cells of central jaw lesions and long bone tumours in respect of both nuclear numerical density and mean absolute cell volume.

Adolescent↗

Immunohistochemical study on histogenesis of congenital epulis and review of the literature.

Congenital epulis is a very rare lesion found only in newborn infants. This tumor is multiple in about 10% of reported cases, rarely with the simultaneous involvement of the maxilla and mandibula, as in this article. In the presented case, light microscopy demonstrated large eosinophilic granular cells arranged in solid nests that are separated by thin fibrovascular areas. The tumors in the maxilla and mandibula were investigated with a panel of polyclonal and monoclonal antibodies, and using immunoperoxidase methods on formalin-fixed, paraffin-embedded sections. Immunohistochemical studies revealed strong and diffuse cytoplasmic staining for neuron specific enolase and vimentin. However, all other reactions were negative. These results suggest that the congenital epulis may be derived from uncommitted nerve-related mesenchymal cells.

Biomarkers, Tumor↗

Primary sarcomas of the jaw.

Nine cases of primary sarcoma of the jaw seen over a period of 14 years are presented. They consisted of four osteosarcomas, three fibrosarcomas, one myxosarcoma and one Ewing's sarcoma. The treatment of choice for osteosarcomas of the mandible is hemimandibulectomy with disarticulation at the temporomandibular joint. Bone graft reconstruction from the iliac crest should be done at a second stage. Palliative maxillectomy for extensive fibrosarcoma of the maxilla served to relieve one patient of local symptoms for more than a year. Myxosarcoma, a variant of fibrosarcoma, and Ewing's sarcoma of the jaw, are very rare conditions, and since these lesions are usually very extensive radiotherapy is the treatment of choice.

Adolescent↗

Ghost cell epithelium in odontomas.

Eight cases from a series of 75 odontomas were found to contain ghost cell epithelium. Clinical, radiologic and histologic findings in these cases did not differ significantly from those of odontomas in general. The results obtained with several staining methods, including rhodamin B under fluorescent light, suggest that the ghost cells represent different stages in the process of ortho-, para- and aberrant keratin formation. Ghost cells should be viewed as the product of metaplastic transformation of the odontogenic epithelium with no significance for the prognosis and treatment of odontomas.

Adolescent↗

Calcifying epithelial odontogenic tumors: a clinicopathologic study of nine cases.

Nine cases of CEOT are reported. There are seven intra-osseous and two extraosseous tumors. All but one occurred in the mandible. The age range was 20 to 64 years; averaging 34.2 years. There were 7 females and 2 males. Radiographically, they appeared either as monocystic or polycystic translucent lesions with radiopaque spots or masses. Embedded teeth were seen in six cases. Microscopically, four different patterns are described. No recurrence has been found postoperatively within 2-14 years of follow-up study. The nature of the reddish homogeneous material, the histogenesis of the tumor and the treatment are briefly discussed.

Adult↗

Ameloblastic fibrosarcoma: an ultrastructural study of the mesenchymal component.

The mesenchymal components of tumors from 2 patients with ameloblastic fibrosarcoma were studied ultrastructurally. The mesenchymal components consisted predominantly of fibroblastic cells with a few histiocytic or fibrohistiocytic cells and myofibroblastic cells. In addition, a very small number of undifferentiated mesenchymal cells were found. We speculate that the mesenchymal components in this tumor may be derived from the undifferentiated mesenchymal cells.

Adult↗

Identification of basement membrane components and intermediate filaments in calcifying epithelial odontogenic tumors.

An immunohistochemical technique was used on paraffin-embedded tissues of four cases of calcifying epithelial odontogenic tumors (CEOT). These studies were performed to gain an additional understanding of the nature of amyloid-like deposits in these tumors. For these studies antibodies to Type IV collagen, laminin, and the five classes of intermediate filament proteins were employed. In all of the tumors examined basement membrane components and intermediate filament proteins (cytokeratin) were demonstrated both in the epithelial tumor islands and within the extracellular amyloid-like deposits. Antibodies to vimentin intermediate filaments were localized only in the stromal fibroblasts. Limited proteolysis or the use of a chaotropic agent was required to express the antigenic determinants present. These studies substantiate the presence of basement membrane components in the amyloid-like deposits of CEOT. In addition, these extracellular deposits are shown to be heterogenous in composition by the immunohistochemical demonstration of cytokeratin intermediate filament proteins.

Adult↗

A comparative histological study of odontogenic keratocysts in basal cell naevus syndrome and control patients.

164 odontogenic keratocysts from 60 patients with the basal cell naevus syndrome were compared with a similar number of single keratocysts matched for age and site. Significant differences between the two groups were found in the numbers of satellite cysts, solid islands of epithelial proliferation and odontogenic rests within the capsule, and in the numbers of mitotic figures in the epithelium lining the main cavity. An index of activity derived from these parameters suggests a greater growth potential in syndrome cysts; in addition, the patterns of association of the features support the theory that the odontogenic rests give rise to satellite cysts.

Adolescent↗

Giant ossifying fibroma: a clinicopathologic study of 8 tumors.

Clinical, radiographic and microscopic features of 8 ossifying fibromas diagnosed in 7 patients and measuring more than 8 cm in greatest diameter, were reviewed. The tumors occurred in both juvenile and middle aged patients and all lesions in women involved the maxilla. The abundance of fibrous connective tissue and resorption of mineralized deposits are indicative of altered cellular differentiation and proliferative activities in large ossifying fibromas. Focal areas of aneurysmal bone cyst formation were identified in the majority of lesions.

Adolescent↗

Histopathologic study of epithelial components in the connective tissue wall of unilocular type of calcifying odontogenic cyst.

Histopathologic study of satellite cysts and odontogenic epithelial islands in connective tissue wall of unilocular type of calcifying odontogenic cyst (COC) was made. The material was 13 cases consisting of 3 simple unicystic COCs, 9 odontome producing COCs and 1 ameloblastomatous proliferating COC. Satellite cysts were found in 6 cases, and were histologically classified into following types: simple cystic, odontome producing and ameloblastomatous. Histologic types of satellite cysts did not coincide with those of main cystic lesions in some cases. Odontogenic epithelial islands with or without proliferating feature were found in 9 cases, and were found in all cases with satellite cysts. Melanin and melanocytes were seen in an ameloblastomatous satellite cysts of 1 of 3 pigmented COCs.

Adolescent↗

Immunohistochemical analysis of bone morphogenetic protein (BMP) in osteosarcoma.

The monoclonal antibody against bovine bone morphogenetic protein (bBMP-McAb) was first used for demonstration of bone morphogenetic protein (BMP) in osteosarcoma. The avidin-biotin complex method (ABC) demonstrated that of the 18 osteosarcomas, 15 stained positive, while all 6 fibrosarcomas were negative. The results showed that BMP mainly exists in the tumor cell plasma and some tumor-like bone tissues. Using this staining method, we can not only differentiate osteosarcoma from fibrosarcoma and other non-bone-derived tumors, but also classify osteosarcoma according to the content and distribution of BMP and the patient's clinical situation, thus providing a scientific basis for clinical treatment.

Adolescent↗

Odontogenic myxoma: histochemical and ultrastructural study.

Three cases of odontogenic myxoma are presented, two of which were located in the mandible and one in the maxilla. All cases demonstrated similar morphology by light microscopy. Immunohistochemical studies demonstrated positive reaction with antibodies to vimentin and actin, and negative reaction to antibody to S-100 protein. A 127-day-old human tooth bud was used as a control. The ultrastructural features performed on Case 3, when combined with the immunohistochemical findings suggest that the cells comprising odontogenic myxoma are of myofibroblastic origin.

Actin Cytoskeleton↗

Experimental odontomas in osteopetrotic op/op rats.

Osteopetrosis is an autosomal recessive disease in several mammalian species. Osteopetrotic op/op rats suffer from complete failure of tooth eruption related to reduced bone resorption. In our earlier studies, op/op rats grafted with bone marrow cells 3 days after birth were cured of the disease and their molar eruption was restored. However, the incisors failed to erupt and their proliferating ends were distorted, forming odontomas. The purpose of the present investigation was to study the odontogenic tissues in the odontomas, using the correlated techniques of radiography and microradiography of undecalcified material, together with histology of decalcified material and scanning electron microscopy.

Animals↗

Odontogenic ghost cell carcinoma: report of four new cases and review of the literature.

Only 12 odontogenic ghost cell carcinomas (OGCC) have been reported in the English language literature to date. This article reports four additional cases of this rare odontogenic tumour and examines them in relation to those previously described. Judging from the number of published cases, the OGCC is more prevalent in Asians than other racial groups, occurs more often in the maxilla than the mandible, and is slightly more common in males than females. Histologically, elements of a benign calcifying odontogenic cyst (COC) can be identified in all the malignant variants, either separated or admixed with the malignant epithelial component. The latter can consist of either small basaloid cells or large epithelial cells. Despite the differing histological presentations, the biological behavior of the tumour is unpredictable, with some cases characterized by relatively indolent growth and others by a locally aggressive and potentially fatal course. The tumour apparently arises most often from malignant transformation of a preexisting benign COC, although it may also develop from other odontogenic tumours.

Adult↗