A giant peripheral ossifying fibroma of the maxilla with extreme difficulty in clinical differentiation from malignancy: a case report and review of the literature.

BACKGROUND: Peripheral ossifying fibroma is a nonneoplastic inflammatory hyperplasia that originates in the periodontal ligament or periosteum in response to chronic mechanical irritation. Peripheral ossifying fibroma develops more commonly in young females as a solitary, slow-growing, exophytic nodular mass of the gingiva, no more than 2 cm in diameter. While various synonyms have been used to refer to peripheral ossifying fibroma, very similar names have also been applied to neoplastic diseases that are pathologically distinct from peripheral ossifying fibroma, causing considerable nomenclatural confusion. Herein, we report our experience with an unusual giant peripheral ossifying fibroma with a differential diagnostic challenge in distinguishing it from a malignancy. CASE PRESENTATION: A 68-year-old Japanese male was referred to our department with a suspected gingival malignancy presenting with an elastic hard, pedunculated, exophytic mass 60 mm in diameter in the right maxillary gingiva. In addition to computed tomography showing extensive bone destruction in the right maxillary alveolus, positron emission tomography with computed tomography revealed fluorodeoxyglucose hyperaccumulation in the gingival lesion. Although these clinical findings were highly suggestive of malignancy, repeated preoperative biopsies showed no evidence of malignancy. Since even intraoperative frozen histological examination revealed no malignancy, surgical resection was performed in the form of partial maxillectomy for benign disease, followed by thorough curettage of the surrounding granulation tissue and alveolar bone. Histologically, the excised mass consisted primarily of a fibrous component with sparse proliferation of atypical fibroblast-like cells, partly comprising ossification, leading to a final diagnosis of peripheral ossifying fibroma. No relapse was observed at the 10-month follow-up. CONCLUSIONS: The clinical presentation of giant peripheral ossifying fibromas can make the differential diagnosis from malignancy difficult. Proper diagnosis relies on recognition of the characteristic histopathology and identification of the underlying chronic mechanical stimuli, while successful treatment mandates complete excision of the lesion and optimization of oral hygiene. Complicated terminological issues associated with peripheral ossifying fibroma require appropriate interpretation and sufficient awareness of the disease names to avoid diagnostic confusion and provide optimal management.

Overexpression of SIP1 and downregulation of E-cadherin predict delayed neck metastasis in stage I/II oral tongue squamous cell carcinoma after partial glossectomy.

BACKGROUND: Patients with clinical stage I/II (T1-2N0M0) oral tongue squamous cell carcinoma (TSCC) usually undergo partial glossectomy alone. However, 14-48% of them develop delayed neck metastasis (DNM), which may lead to an unfavorable course. Recently epithelial-to-mesenchymal transition (EMT) has been thought to play a crucial role in cancer metastasis. The present study aimed to examine the associations of EMT-involved molecular factors and clinicopathological factors with DNM in stage I/II TSCC. METHODS: mRNA expression levels of E-cadherin and its transcriptional repressors (snail, SIP1, and twist) in 7 head and neck squamous cell carcinoma (HNSCC) cell lines were evaluated by quantitative real-time PCR. Clinicopathological parameters and immunohistochemical expressions of E-cadherin and its repressors were examined in surgical specimens of 37 stage I/II TSCC patients who underwent partial glossectomy alone. RESULTS: In HNSCC cells, E-cadherin expression was inversely correlated with SIP1 expression (P = 0.023). Univariate analysis of immunohistochemistry showed that overexpression of SIP1 and loss of E-cadherin were significantly correlated with DNM, although no inverse correlation was found between E-cadherin and its repressors. Multiple logistic regression analysis including clinicopathological and molecular factors revealed that overexpression of SIP1 (P = 0.005), loss of E-cadherin (P = 0.046), and vascular invasion (P = 0.024) were independently correlated with DNM. CONCLUSIONS: These results suggest that development of DNM in stage I/II TSCC is closely related to induction of EMT in primary tumor cells. Especially, SIP1 and E-cadherin are considered to be the possible markers for selecting patients at high risk of DNM.

Complicated surgical resection of malignant tumors in the upper cervical spine after failed ion-beam radiation therapy.

STUDY DESIGN: Case report. OBJECTIVE: To report 3 cases of malignant tumors in the upper cervical spine that were treated surgically by a combination of posterior tumor resection and stabilization and anterior tumor resection through a mandible-splitting approach after failed ion-beam radiation therapy. SUMMARY OF BACKGROUND DATA: Few clinical reports have described in detail the postoperative complications associated with transoral surgical resection of tumors in the upper cervical spine after unsuccessful ion-beam radiation therapy. METHODS: Three patients with malignant tumors in the upper cervical spine who had undergone ion-beam radiotherapy and experienced tumor recurrence were treated by a combination of posterior and anterior surgery through a mandible-splitting approach. One patient (patient 1, a 32-year-old man) had a hemangioendothelioma at the C2 and C3 level, whereas the other 2 patients (patient 2, a 66-year-old woman and patient 3, a 65-year-old man) had a chordoma at the C2 and C3 level. RESULTS: The intralesional but macroscopic total resection of the tumors was achieved in all 3 patients. However, serious complications developed after surgery, including deep wound infection, cerebrospinal fluid leakage, and meningitis in patient 1, prolonged swallowing difficulty, subsidence of the strut graft, and recurrence in patient 2, and deep wound infection and discitis causing progressive paralysis in patient 3. All patients underwent salvage surgery, including debridement of the wound in patient 1, posterior reinforcement using instrumentation and posterior tumor resection for the recurrent tumor in patient 2, and anterior debridement of the wound with a pedicle flap using the pectoral major muscle in patient 3 to address these problems. Patients 1 and 3 had no signs of recurrence at the time of a follow-up examination. CONCLUSION: Severe complications, mainly associated with the disturbance in healing of the retropharyngeal wall, were observed in all 3 patients. A preventive method, such as primary repair of the retropharyngeal wall using muscular/musculocutaneous flaps, should be considered for patients undergoing resection through a transoral approach after ion-beam irradiation.

Experimental evaluation of relapse-risks in operated zygoma fractures.

OBJECTIVES: Prevention of relapse, or postoperative dislocation, of the fixed zygoma is necessary to achieve optimal results in the treatment of zygoma fractures. Assuming that the occurrence of intensified stresses on mastication at the screw-bone interface (SBI) constitutes the essential cause of the relapse, we evaluated the stresses for three different fixation methods-fixation at the frontal process (FP), inferior orbital rim (IOR), and zygomatico-maxillary buttress (ZMB). METHODS: We used 10 computer-aided design (CAD) models simulating zygoma fractures in the experiment. For each CAD model, we fixed the fractured zygoma with four screws and one mini-plate at the FP, IOR, or ZMB. After applying a 5.5kg force simulating mastication, we calculated the intensity and distribution patterns of the stresses occurring at the SBIs of the fixation screws using the finite element method. Thereby, we evaluated dynamic stability of the fixed zygoma for each of the three fixation methods. RESULTS: Greater stresses occur at the SBIs with IOR fixation than at those with FP and ZMB fixation. Although the stresses occurring at the SBIs on mastication demonstrated evenly distributed patterns with the FP and ZMB fixation, the stresses demonstrated concentration on one screw with the IOR fixation. CONCLUSIONS: The fixed zygoma is more likely to cause relapse with the IOR fixation than with the FP or ZMB fixation. Hence, in performing zygoma fixation at the IOR, care should be taken to minimize the likelihood of postoperative relapse that is caused by skewed distribution of the stresses on the fixation screws.