Intraosseous leiomyosarcoma of the mandible: a case report

Leiomyosarcomas are rare smooth muscle tumors that can occur anywhere in the body. These tumors rarely occur in the head and neck owing to the limited amount of smooth muscle in the region. The clinical diagnosis of leiomyosarcoma is challenging because of the nonspecific presentation of the disease. The most definitive diagnosis is based on tissue biopsy or surgical resection and histopathologic confirmation. A case of intraosseous leiomyosarcoma of the mandible and a review of the literature are presented.

Computer-aided stereolithography for presurgical planning in fibula free tissue reconstruction of the mandible

INTRODUCTION

Computer-aided imaging has facilitated presurgical modeling for free tissue mandibular reconstruction. The purpose of this study is to illustrate the utility of preoperative virtual surgical planning in fibula reconstruction of the mandible.

METHODS

Eight patients, age 17 to 72 years, treated between November 2009 and January 2011 were reviewed. Each required segmental resection and reconstruction of the mandible and were managed with presurgical virtual planning.

RESULTS

Our series includes five cases of squamous cell carcinoma (SCCA), one case of osteoradionecrosis (ORN), one leiomyosarcoma, and one odontogenic myxoma. All patients underwent a segmental resection of the mandible 5 to 14 cm in size (average 8 cm). In each case, prefabricated guides for segmental mandibulectomy and fibula osteotomy were employed and resulted in simplification of bony inset and reduced need for "fine tuning" of fibula segments.

CONCLUSIONS

Virtual surgical planning fosters multidisciplinary communication and provides accurate presurgical planning. This allows seamless reconstruction in patients requiring mandibular reconstruction via fibula free tissue transfer. The combination of mandibular and fibular cutting guides and templates allows for a precise and efficient surgical reconstruction. In our experience, this technology is most useful in the reconstruction of large mandibular defects requiring large reconstruction plates and multiple fibular osteotomies.

Maxillofacial oncology at the University of Minnesota: treating the epidemic of oral cancer

INTRODUCTION

Oral cancer may present with a variety of signs and symptoms including pain, dysphagia, non-healing ulcers, red and white lesions, and indurated masses. Historically, oral cancer has been associated with the male population, particularly those who use tobacco and alcohol. Recently, there has been a dramatic increase in oral cancer rates seen in the population aged 40 years and younger. This increase has not been associated with the traditional risk factors for oral cancer and is likely linked to etiologic factors that remain still undefined. The proliferation of oral cancer is also mirrored by an increase in oropharyngeal malignancies such as base of tongue and tonsil cancer, although the increase in this subset of patients appears to be clearly associated with Human Papillomavirus (HPV).

METHODS

We present a summary of all oral malignancies treated at the University of Minnesota Oral and Maxillofacial Surgery Division from 2008 through early 2011.

RESULTS

Since July of 2008, the Oral and Maxillofacial Surgery Department at the University of Minnesota has been referred a total of 69 cases of head and neck malignant tumors, of which 58 were primarily managed with surgery. A broad range of head and neck cancers were seen, with the most common being oral squamous cell carcinoma (OSCC), which accounted for 81% of patients treated by oncologic tumor resection. The tongue was the most common site of occurrence of OSCC with 33% of cases. There was an even distribution between genders. Traditional treatment modalities included surgical resection of primary tumors including neck dissection, when indicated, with postoperative adjuvant therapies being reserved for advanced stage tumors or high-risk pathologic features for recurrence. At the conclusion of the study period in January, 2011, 83% of patients treated surgically for OSCC were living disease free, 4% had recurrent tumors not amenable to resection, 6% of patients had died from other causes, and 6% had succumbed to OSCC, resulting in a disease-specific survival rate of 93% with an overall survival rate of 87%.

CONCLUSIONS

Oral cancer continues to be diagnosed with advanced stage disease in 50% of patients. Dental practitioners play a significant role in the early detection and diagnosis of oral cavity cancer. It is incumbent upon dental practitioners to be aware of the early signs and symptoms of oral cancer and to make prompt referral to head and neck cancer specialists when indicated. Diligent and frequent examination, particularly in patients with risk factors, will greatly improve survival rates and minimize the complexity and morbidity of oncologic treatment when patients are diagnosed with earlier stage disease.

Effect of osteoporotic status on the survival of titanium dental implants

OBJECTIVES

The aim of this study was to determine whether a diagnosis of osteoporosis affected the survival rate of osseointegrated dental implants. Other variables that were studied were age, arch location of the implant, and smoking status on the effect of dental implant survival.

MATERIALS AND METHODS

A retrospective chart review was completed on all women who were 50 years of age or older at the time of dental implant placement at the Mayo Clinic between October 1, 1983, and December 31, 2004. Osteoporotic status was defined on the basis of bone mineral density (BMD) score utilizing World Health Organization criteria. Univariate analyses were performed to evaluate the following independent variables' effect on implant survival: BMD T-score, age, osteoporosis status, arch location of the implant, and smoking status at the time of implant placement.

RESULTS

A total of 3,224 implants in 746 female patients 50 years of age or older at the time of implant placement were evaluated. BMD scores within 3 years of implant placement were available for 646 implants (192 patients). In this group, 37 implant failures were noted. The 5-year implant survival rate was 93.8% in the group of patients with BMD scores. In this group of 192 patients, there were 94 (49%) who were not diagnosed with osteopenia or osteoporosis, 57 (29.7%) with a diagnosis of osteopenia, and 41 (21.4%) with a diagnosis of osteoporosis. Patients with a diagnosis of osteoporosis or osteopenia were not significantly more likely to develop implant failure compared to those without such a diagnosis (HR = 1.14, 95% CI = 0.50 to 0.60, P = .76 and HR = 0.98, 95% CI = 0.40 to 2.42, P = .97, respectively). Arch location and BMD score did not have a statistically significant effect on implant survival rates. The only tested variable to demonstrate a significant effect was smoking. Implants in patients who were smokers during the time of implant placement were 2.6 times more likely to fail compared to implants placed in patients who did not smoke (HR = 2.6, 95% CI = 1.20 to 5.63; P = .016).

CONCLUSIONS

Based upon the data derived from this retrospective study of 192 women at least 50 years of age at the time of implant placement, the following observations were made: (1) a diagnosis of osteoporosis and osteopenia did not contribute to increased risk of implant failure and (2) implants placed in patients who were smokers at the time of implant placement were 2.6 times more likely to fail than implants placed in nonsmokers. Based on these data, a diagnosis of osteoporosis or osteopenia is not a contraindication to dental implant therapy.

Differential loss of expression of common fragile site genes between oral tongue and oropharyngeal squamous cell carcinomas

The common fragile sites (CFSs) are large regions of profound genomic instability found in all individuals. A number of the CFSs have been found to span genes that extend over large genomic regions (>700 kb). The expression of these genes is frequently abrogated in a number of different cancers and several of them have already been shown to function as tumor suppressor genes, both in vitro and in vivo. We analyzed the expression of 14 large CFS genes in two distinct groups of head and neck cancers using real-time RT-PCR. The first were oral tongue squamous cell carcinomas (SCCs) and the second were base of tongue/tonsillar (oropharyngeal) SCCs. These two groups were previously examined for the presence of human papillomavirus (HPV) and while 46% of the oropharyngeal cancers were positive for HPV16 only one of 52 oral cancers contained HPV16 sequences. We observed a distinct pattern of loss of expression of the large CFS genes in the two groups of head and neck cancers. In addition, there was no correlation between the relative instability in different CFS regions and which genes were inactivated. Thus, this report demonstrates another distinction between these two groups of head and neck cancer. In addition, it suggests that there is selection for loss of expression of specific CFS genes in these cancers.

Reconstruction of head and neck defects: a systematic approach to treatment

Reconstruction of composite maxillofacial defects after tumor excision or trauma is difficult. The role of the reconstructive surgeon is to have a diverse armamentarium of reconstructive options to enable an aesthetic and functional reconstruction while minimizing the morbidity to the patient. This article will present a systematic review of composite maxillofacial reconstruction with free tissue transfer.