Precancerous skin lesions and carcinomas in situ of the skin represent the early stages of epithelial skin tumors. There is no invasive tumor growth, so the basement membrane is completely intact. These lesions show a wide variation of clinical and histological appearances on the skin or mucosa. The precancerous and carcinoma in situ lesions that are described in this text are actinic keratosis, actinic cheilitis, cutaneous horns, arsenical keratosis, tar-induced dermatosis, X-ray irradiation-related keratosis, Bowen's disease, erythroplasia of Queyrat, bowenoid papulosis, intraepithelial neoplasia (vulvar, penile and anal). Because they all can progress into invasive carcinoma, therapy is mandatory. Many noninvasive therapeutic approaches exist nowadays in the form of gels, creams, photodynamic therapy and invasive techniques such as laser therapy and cryotherapy, curettage and excision of lesional skin. Depending on the treatment process, different rates of general clearance and recurrence of the lesions are discussed in this article.

Adjunctive techniques like DNA image cytometry (DNA-ICM) have been attributed to enhance the diagnostic performance of oral brush biopsies. The aim of the study was an evaluation of brush biopsies, analysed according to morphological criteria and by DNA-ICM vs. histological findings in a blinded prospective trial.Eighty eight brush biopsies of 70 patients were sampled. Only clinical suspicious but not evident malignant oral lesions were included. Clinical diagnosis was leukoplakia (n = 36), lichen planus (n = 18), verruciform erythroplakia (n = 12), erythroleukoplakia (n = 9), erosion (n = 7) and induration (n = 6). Evaluation was conducted via histology, cytology and DNA-ICM.Histological diagnosis revealed eight cases of squamous intraepithelial dysplasia (SIN 1 n = 6, SIN 2 n = 2), four cases of carcinoma-in situ and 25 cases of oral T1-cancer. Remaining cases were leukoplakia (n = 28), lichen planus (n = 15) and local inflammation (n = 8). Brush biopsy detected malignant lesions including SIN>1 with a sensitivity of 55% and a specificity of 100%. DNA-ICM had a sensitivity of 70% and a specificity of 100%. The combination of both methods showed a sensitivity of 76% and a specificity of 100%. The predominant reason for false negative results were sampling errors with insufficient cells (86% in brush biopsy and 100% in DNA-ICM).DNA-ICM has the potential to substantially improve the sensitivity of a pure morphological interpretation of oral brush biopsies. Method inherent sampling errors may be accountable for a lower sensitivity compared to conventional histological diagnosis. Therefore, DNA-ICM should not be used to rule out malignancy, when lesions are already clinically suspicious for oral cancer.

An estimated 36.38% of oral cancer cases in Colombia are lethal. Most cases are diagnosed in late stages, so early detection and control of risk factors would be the most effective tools for prevention. The aim of this study was to use a questionnaire to evaluate knowledge and practices regarding oral cancer among a group of dentists in southern Colombia. A sample of 93 dentists was asked to respond to a confidential survey which was based on prior studies. It was found that one quarter of the respondents knew that squamous cell carcinoma is the most frequent form of oral cancer and that leukoplakia and erythroplakia are the two lesions most probably associated to oral cancer. Most respondents believe they advise their patients adequately about suspicious lesions. Three quarters believe they are prepared to explain the risks of smoking. Over half evaluate their patients' personal history of tumors and less than one quarter evaluate the history of cancer in patients' families. In general, an oral examination is performed for cancer diagnosis and almost all the respondents consider it important to keep up to date. A statistically significant correlation was found between dentists 'belief that they are adequately prepared to perform a physical examination and having attended a "formal course within the past 12 months". This study revealed that dentists' level of knowledge and application of preventive measures are an important part of the public health strategy for reducing the morbidity and mortality for oral cancer.

The aetiology of oral premalignant lesions is unknown. Oxidative stress is associated with inflammation and cancerogenesis. The aim of our study was to compare salivary markers of oxidative and carbonyl stress in patients with oral premalignant lesions and age-matched healthy controls. Unstimulated saliva samples were collected from 16 patients with oral premalignant lesions (leukoplakia, lichen planus, erythroplakia) and 16 age-matched healthy controls. Biochemical analysis included measurement of thiobarbituric acid reacting substances (TBARS), advanced oxidation protein products (AOPP), advanced glycation endproducts (AGEs) and total antioxidant capacity (TAC). Salivary RNA was analyzed using real time PCR. Salivary TBARS and AGEs were significantly higher in patients than in controls. No differences were found in AOPP. TAC and expression of superoxide dismutase were lower in patients than in age-matched controls. Other analyzed transcripts (vascular endothelial growth factor, sialotransferase, neuraminidase) did not differ between patients and the control group. Markers of lipoperoxidation and carbonyl stress were increased in patients with oral premalignant lesions. Decreased antioxidant status potentially due to decreased expression of antioxidant enzymes might be responsible for these findings. Our results might point to the aetiology or pathogenesis of oral premalignant lesions as well as to the mechanism of transition to oral carcinoma.

Photodynamic therapy (PDT) with methyl aminolevulinate (MAL) has been suggested as a useful treatment option in a number of skin tumors, other than approved indications, and infections. However, evidence is poor because it is mainly supported by isolated case reports or small case series, often with conflicting results. To assess the effectiveness, tolerability and safety of off-label MAL-PDT in daily clinical practice in 20 Italian hospitals, a retrospective observational study of medical records of patients treated for off-label oncologic and infectious skin conditions was carried out. In all patients standard treatment options had been either ineffective, unacceptably toxic, or medically contraindicated. Clinical data from 145 patients were analyzed. Actinic cheilitis showed a complete remission (CR) in 27 out of 43 treated patients and CR was maintained at follow-up. CR was registered in 3 of 8, 5 of 8 and 10 of 17 treated patients who were affected by extra-mammary Paget's disease (EMPD), erythroplasia of Queyrat (QD), and invasive squamous cell carcinoma (SCC), respectively. Five out of 19 patients with cutaneous T cell lymphoma had a complete remission. Cutaneous B-cell lymphoma, malignant fibrous histiocytoma, mastocytosis and nevus sebaceous were not responsive. Warts were treated in 30 patients and 15 had a complete remission. However, periungueal and plantar lesions were much more responsive than flat and common lesions. Condylomata showed a CR in 2 out of 5 male patients but treatment was painful. Bowenoid papulosis showed only a partial improvement. Atypical mycobacteriosis and chronic cutaneous leishmaniasis were successfully treated. Submammary candidal intertrigo and interdigital intertrigo with Pseudomonas aeruginosa did not improve. Among off-label oncological uses of MAL-PDT, the therapy of actinic cheilitis was the most investigated and showed the best results. In addition, MAL-PDT was used successfully in the majority of patients with QD, EMPD and invasive SCC. Treatment of specific cutaneous infections was well tolerated and gave a good therapeutic result in a few patients, but it does not seem to give substantial advantages over conventional treatment options.

Oral erythroplakia (OE) is a notoriously aggressive oral pre-malignant lesion with a high tendency to oral cancer development, but its biological behavior is largely unknown. The objective of this study was to determine the expression of cancer stem cell markers ALDH1 and Bmi1 in OE and their correlation with malignant transformation of OE.In a retrospective case-control study, expression patterns of ALDH1 and Bmi1 were determined using immunohistochemistry in samples from 34 patients with OE, including patients with untransformed lesions (n=17) and patients with malignant transformed lesions (n=17).ALDH1 and Bmi1 expression was observed in 19 (55.9%) and 20 (58.8%) of 34 patients with OE, respectively. Multivariate analysis revealed that ALDH1 expression was significantly associated with increased risk of transformation (P<0.05), but Bmi1 expression was not a significant marker (P > 0.05). Notably, the coexpression of both ALDH1 and Bmi1 was a strong indicator associated with 8.56-fold (95% confidence interval [CI], 1.74-42.17; P<0.01) for malignant transformation. Point prevalence analysis revealed that 78.6% (95% CI, 54.0-100) of the patient with coexpression of both ALDH1 and Bmi1 developed oral cancer.Our data indicated that the expression patterns of ALDH1 and Bmi1 in OE were associated with malignant transformation, suggesting that they may be valuable predictors for evaluating the risk of oral cancer.

Warfarin is an oral anticoagulant, used routinely for patients with atrial fibrillation, deep vein thrombosis, pulmonary embolism and those with a mechanical prosthetic valve. There are several noted adverse reactions associated with its use, in particular the risk of haemorrhage. Other adverse reactions include: hypersensitivity, rash, alopecia, diarrhoea, unexplained drop in haematocrit, purple toes, skin necrosis, jaundice, hepatic dysfunction, nausea, vomiting and pancreatitis. In this case report, an interesting potential adverse reaction to warfarin is discussed. The reaction described affected the patient's tongue, without affecting any other aspect of the oral cavity or body. Clinical Relevance: This case report highlights the potential problems that can be encountered by patients on warfarin therapy, specifically, the possibility for hypersensitivity type reactions.

Most oral malignancies are squamous cell carcinomas (OSCC). Incidence of OSCC is increasing in both genders, and survival rates remain poor. OSCC is frequently preceded by potentially malignant disorders (OPMD), which include leukoplakia, erythroplakia and lichen planus. OSCC is preventable because the risk factors are known: smoking and alcohol consumption, snuff and human papillomavirus infections. Fresh vegetables, fruit and fish provide protection from OSCC. Regular systematic examination is essential to the early detection of OSCC and OPMD. Treatment of oral cancers comprises either surgery alone, or combined with radiotherapy and chemotherapy. Management of patients with OPMD and treated OSCC include careful life-long follow-up.