Lars Sand

Viruses and oral cancer. Is there a link

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour of the oral cavity. The aetiology of epithelial cancer of the head and neck is considered to be a multifactorial, sequential process. DNA viruses are found in many different cancers and are also capable of transforming cells to a malignant phenotype. Human Papilloma Virus (HPV) has been proposed as risk factors in OSCC development and HPV type 16 is the most important subtype. Other oncogenic virus species i.e., Epstein-Barr Virus and Herpes Simplex Virus Type 1 have been proposed to be involved in oral carcinogenesis. However, no convincing evidence exist that they are an established risk factor in OSCC. Therefore more studies are needed in order to clarify the different aspects of virus involvement. Here, we review the existing literature on viral involvement in oral cancer.

A retrospective study of patients with mandibular fractures treated at a Swedish University Hospital 1999-2008

Background: Fracture of the mandible is one of the most common fractures of the maxillofacial skeleton. However, the etiology, gender, and age distribution vary between different regions and countries, and the purpose of this study was to evaluate the current trend of patients with mandibular fractures at the Department of Oral and Maxillofacial Surgery, in Uppsala, Sweden. Aim: The aim of this retrospective study was to analyze patients with mandibular fractures treated in the University Hospital of Uppsala (the county capital of Uppland) Sweden during a 10-year period (1999-2008). Materials and Methods: This study was designed as a retrospective study of patients admitted to the Department of Oral and Maxillofacial Surgery at Uppsala University Hospital, Sweden. The location of fractures was evaluated clinically by the surgeon and on the X-rays. We classified the data according to gender, age, etiology, day of the week, month of the year, fracture site, and method of treatment of the fractures. Results: Records were collected from patient charts from 266 patients. One hundred eighty-seven patients (70%) with mandibular fractures were of male gender, and 132 patients (50%) were aged 16-30 years. Interpersonal violence constituted the most common etiological factor for mandibular fractures (24%), followed by falls (23%). Forty-nine percentages of the patients were treated surgically, and 51% were treated conservatively. There was an increase of the annual incidence of fractures toward the end of the period, even though not statistically significant. Conclusions: Mandibular fractures occurred primarily among younger men between 16- and 30-year-old. Condyle fractures were the most common fracture site and 50% of the patients required surgery. Summer months and weekends were the most common time of mandibular fractures.

Nested PCR for detection of HSV-1 in oral mucosa.

Background It has been estimated that 15%-20% of human tumours are driven by infection and inflammation, and viral infections play an important role in malignant transformation. The evidence that herpes simplex virus type 1 (HSV-1) could be involved in the aetiology of oral cancer varies from weak to persuasive. This study aimed to investigate by nested PCR (NPCR) the prevalence of HSV-1 in samples from normal oral mucosa, oral leukoplakia, and oral squamous cell carcinoma (OSCC). Material and Methods We investigated the prevalence of HSV-1 in biopsies obtained from 26 fresh, normal oral mucosa from healthy volunteers as well as 53 oral leukoplakia and 27 OSCC paraffin-embedded samples. DNA was extracted from the specimens and investigated for the presence of HSV-1 by nested polymerase chain reaction (NPCR) and DNA sequencing. Results HSV-1 was detected in 14 (54%) of the healthy samples, in 19 (36%) of the oral leukoplakia samples, and in 14 (52%) of the OSCC samples. The differences were not statistically significant. Conclusions We observed a high incidence of HSV-1 in healthy oral mucosa, oral leukoplakia, and OSCC tissues. Thus, no connection between OSCC development and presence of HSV-1 was detected. Key words:HSV-1, nested PCR, PCR.

Prevalence of human papillomavirus in oral lichen planus in an Iranian cohort

Context: Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease with female predominance with the potential for malignant transformation. Human papillomavirus (HPV) is associated with both malignant and benign disease in the head and neck region. Aims: The present study assesses the prevalence of high-risk HPV-16 and HPV-18 in tissue and saliva samples from an Iranian population diagnosed with OLP. Subjects and Methods: Deoxyribonucleic acid was extracted and investigated using polymerase chain reaction from tissue and saliva samples of the same individuals from 40 OLP cases and saliva samples of 40 healthy controls. Statistical Analysis: The prevalence of data was compared using the Chi-square test and inter-group differences were analyzed using Fishers exact test. Results: OLP specimens were HPV-positive in 11 of 40 (27.5%) cases compared with three of 40 (7.5%) saliva specimens, representing a statistically significant difference (P = 0.0367). HPV-16 and HPV-18 were positive in eight of 40 (20%) OLP tissues and three of 40 (7.5%) saliva samples. Five of the 40 healthy saliva samples were positive for HPV-16. In the OLP patients with dysplasia, four of seven tissue samples were HPV-positive; threeof these four were HPV-16- positive in comparision with seven of 33 HPV-positive samples from OLP patients without dysplasia. Conclusions: Biopsies were more accurate than saliva analysis for evaluating HPV prevalence in OLP patients. HPV prevalence was higher in dysplastic than nondysplastic OLP lesions in this Iranian cohort.