Clinical predictors of malignant transformation and recurrence in oral potentially malignant disorders: A systematic review and meta-analysis

OBJECTIVE

We performed a systematic review dedicated to pooling evidence for the associations of clinical features with malignant transformation (MT) and recurrence of 3 oral potentially malignant disorders (OPMDs) (actinic cheilitis [AC], oral leukoplakia [OL], and proliferative verrucous leukoplakia [PVL]).

STUDY DESIGN

We selected studies that included clinical features and risk factors (age, sex, site, size, appearance, alcohol intake, tobacco use, and sun exposure) of OL, PVL, and AC associated with recurrence and/or MT.

RESULTS

Based on the meta-analysis results, non-homogeneous OL appears to have a 4.53 times higher chance of recurrence after treatment. We also found 6.52 higher chances of MT of non-homogeneous OL. Another clinical feature related to higher MT chances is the location (floor of the mouth and tongue has 4.48 higher chances) and the size (OL with >200 mm2 in size has 4.10 higher chances of MT). Regarding habits, nonsmoking patients with OL have a 3.20 higher chance of MT. The only clinical feature related to higher chances of MT in patients with PVL was sex (females have a 2.50 higher chance of MT).

CONCLUSIONS

Our study showed that some clinical features may indicate greater chances of recurrence after treatment and MT of OPMD.

Incidence of radiodermatitis in breast cancer patients during hypofractionated radiotherapy

ABSTRACT Objective: To analyze the incidence, dose of occurrence, grade, severity, and associated risk factors for the development of radiodermatitis, by area of the irradiated breast, in women with breast cancer, during hypofractionated radiotherapy. Method: Observational, prospective, and longitudinal study, according to the guidelines of the Strengthening the Reporting of Observational studies in Epidemiology, carried out between May 2019 and May 2021. Results: A total of 104 women participated in the study, and 73.1% (95%CI: 64–82) developed signs of radiodermatitis during treatment. The majority (63.5%, 95%CI: 54–73) developed erythema in the axillary region with about 36.5 Grays. Women with large breasts and statin users are more likely to develop radiodermatitis. However, women with Phototype III skin color classification (light brown skin) are less likely to develop radiodermatitis, with skin color being a protective factor. Conclusion: The incidence of radiodermatitis in women with breast cancer during hypofractionated radiotherapy is significant. Therefore, the development of protocols for the management of this radiotoxicity is suggested, considering the cumulative dose and associated risk factors.

Incidência de radiodermatite em pacientes com câncer de mama durante a radioterapia hipofracionada

RESUMO Objetivo: Analisar a incidência, a dose de ocorrência, o grau, a severidade e os fatores de risco associados para o desenvolvimento de radiodermatite, por área da mama irradiada, em mulheres com câncer de mama, durante a radioterapia hipofracionada. Método: Estudo observacional, prospectivo e longitudinal, conforme diretrizes do Strengthening the Reporting of Observational studies in Epidemiology, realizado entre maio de 2019 e maio de 2021. Resultados: Participaram do estudo 104 mulheres, 73,1% (IC95%: 64–82) desenvolveram sinais de radiodermatite durante o tratamento. A maioria (63,5%, IC95%: 54–73) desenvolveu eritema na região axilar com cerca de 36,5 Grays. Mulheres com mamas volumosas e usuárias de estatinas possuem maior chance de desenvolver radiodermatite. Entretanto, mulheres com a cor da pele classificada como Fototipo III (pele morena clara) possuem menor chance de desenvolver radiodermatite, sendo a cor da pele um fator protetor. Conclusão A incidência de radiodermatite em mulheres com câncer de mama durante a radioterapia hipofracionada é expressiva. Sugere-se, portanto, o desenvolvimento de protocolos para o manejo desta radiotoxicidade, considerando a dose cumulativa e fatores de risco associados.

Antiproliferative effects of metformin in cellular models of pheochromocytoma

Pheochromocytomas (PCCs) are rare neuroendocrine tumors derived from adrenal medulla chromaffin cells. Malignancy and recurrence are rare but demand effective treatment. Metformin exerts antiproliferative effects in several cancer cell lines. We thus evaluated the effects of metformin on cell viability and proliferation, cellular respiration and AMPK-AKT-mTOR-HIFA proliferation pathway on a rat PCC cell line (PC12-Adh). We then addressed metformin's effects on the AMPK-AKT-mTOR-HIFA pathway on two human primary cultures: one from a VHL-mutant PCC and other from a sporadic PCC. Metformin (20 mM) inhibited PC12-Adh cell proliferation, and decreased oxygen consumption, ATP production and proton leak, in addition to loss of mitochondrial membrane potential. Further, metformin induced AMPK phosphorylation and impaired AMPK-PI3k-AKT-mTOR pathway activation. The mTOR pathway was also inhibited in human VHL-related PCC cells, however, in an AMPK-independent manner. Metformin-induced decrease of HIF1A levels was likely mediated by proteasomal degradation. Altogether our results suggest that metformin impairs PCC cellular proliferation.

Prognostic biomarkers for malignant transformation of oral potentially malignant disorders: a scoping review protocol

OBJECTIVE

This scoping review aims to identify and systematically map the available evidence concerning the prognostic biomarkers for malignant transformation of oral potentially malignant disorders (OPMDs), and to identify and analyze possible knowledge gaps in this field of literature.

INTRODUCTION

It is hypothesized that diagnosis and treatment of oral cancer in its early stages may be the key to improving the prognosis and reducing treatment-related consequences. Oral potentially malignant disorders represent tissue alterations with a higher risk of malignant transformation compared to the normal mucosa. Therefore, the study of prognostic biomarkers for OPMD could represent new diagnosis and therapeutic targets and, consequently, contribute to the reduction of oral cancer burden worldwide.

INCLUSION CRITERIA

Longitudinal studies investigating prognostic biomarkers regarding the malignant transformation of OPMD will be included. The initial OPMD diagnosis and the malignant transformation must have been confirmed by histopathological analysis. To achieve minimal heterogeneity, studies that assess biomarkers in other locations (blood, plasma or others) will be excluded.

METHODS

Five electronic databases and three grey literature databases will be consulted. No restrictions regarding publication date will be applied. Only studies published in the Latin (Roman) alphabet, which comprises most of the European languages, will be included. Study selection will be performed by two authors in a two-phase process; if any disagreement arises, a third author will be consulted to make a final decision. Data extraction will be performed by two authors using a standardized extraction tool. The results will be described in details accordantly with the aims of this scoping review.

Clinicopathological analysis and survival outcomes of primary salivary gland tumors in pediatric patients: A systematic review

BACKGROUND

Salivary gland tumors are a diverse group of uncommon neoplasms that are rare in pediatric patients. The aim of this study was to evaluate the clinicopathological profile and survival outcomes of pediatric patients affected by salivary gland tumors.

MATERIALS AND METHODS

An extensive search was carried out using the MEDLINE/PubMed, EMBASE, Scopus databases, and grey literature. The risk of bias was available in all papers included.

RESULTS

A total of 2,830 articles were initially retrieved with 54 remaining for data extraction, resulting in 2,937 cases. This comprised forty-five case series' and nine cohort studies. These tumors were slightly more prevalent in females (57.4%). The patients' age ranged from 0.3 to 19 years old, with a mean age of 13.3 years. Parotid was the most affected site (81.9%), and 99.2% of cases clinically exhibited a swelling. Presence of pain/tenderness was reported in 13.5% of the cases, with an average duration of 12.6 months for the appearance of symptoms. Most of the reported cases were malignant tumors (75.4%), with mucoepidermoid carcinoma the most common tumor of all tumors (44.8%), followed by pleomorphic adenoma (24.1%). Surgery alone was the leading treatment choice in 74.9% cases, and the 5-year overall survival rate of patients was 93.1%. Patients with symptoms (P = .001), local recurrence (P < .001), metastasis (P < .001), and those not undergoing surgery or surgery combined with radiotherapy (P < .001) showed lower survival rates.

CONCLUSION

The pediatric patients present a high frequency of malignant salivary neoplasms and a high overall survival rate.

Effects of dual blockade in heart failure and renal dysfunction: Systematic review and meta-analysis

OBJECTIVE

The effect of dual renin-angiotensin system (RAS) inhibition in heart failure (HF) is still controversial. Systematic reviews have shown that dual RAS blockade may reduce mortality and hospitalizations, yet it has been associated with the increased risk of renal dysfunction (RD). Surprisingly, although RD in patients with HF is frequent, the effect of combining RAS inhibitors in HF patients with RD has never been studied in a meta-analysis.

METHODS

A systematic review and meta-analysis of randomized clinical trials involving HF patients with RD who received dual blockade analyzing death, cardiovascular (CV) death or HF hospitalization, and adverse events.

RESULTS

Out of 2258 screened articles, 12 studies were included (34,131 patients). Compared with monotherapy, dual RAS inhibition reduced hazard ratio of death to 0.94 (p=0.07) and significantly reduced CV death or HF hospitalization to 0.89 (p=0.0006) in all individuals, and to 0.86 (p=0.005) in patients with RD and to 0.91 (p=0.04) without RD. Nevertheless, dual RAS blockade significantly increased the risk of renal impairment (40%), hyperkalemia (44%), and hypotension (42%), although discontinuation of treatment occurs only in 3.68% versus 2.19% (p=0.00001).

CONCLUSIONS

Dual RAS inhibition therapy reduces the risk of CV death or HF hospitalization. However, cautions monitoring for specific adverse events may be warranted.

Prevalence of oral mucosal disorders during pregnancy: A systematic review and meta‐analysis

OBJECTIVE

To assess the prevalence of oral mucosal disorders during pregnancy.

METHODS

Observational studies were selected by two reviewers in a two-phase process. Search strategies were applied at CINAHL, LILACS, LIVIVO, PubMed, Scopus, Web of Science, Google Scholar, OpenGrey, and ProQuest. The risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated by the software R Statistics version 3.5.1 (The R Foundation, Vienna, Austria). Confidence in cumulative evidence was assessed by using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

Fifteen studies met the eligibility criteria and were selected for qualitative synthesis and meta-analysis, of which 5935 participants were enrolled. The overall prevalence of oral mucosal disorders was 11.8%. Gingival hyperplasia (17.1%), morsicatio buccarum (10%), oral candidiasis (4.4%), pyogenic granuloma (3%), and benign migratory glossitis (2.8%) were the most prevalent lesions. The overall risk of bias was considered moderate, and the quality of evidence was very low.

CONCLUSION

Disorders of the oral mucosa were present in approximately 1 out of 10 pregnant women. Gingival hyperplasia was the most prevalent lesion. Further studies should apply homogeneous methodology to improve the quality of evidence.

Oropharynx HPV status and its relation to HIV infection

Background

The number of oropharyngeal lesions caused by HPV (Human papillomavirus) has been increasing worldwide in the past years. In spite of the clinical relevance of HPV infection in the anogenital tract of HIV-positive patients, the relevance of oropharynx HPV infection in these patients is not clear. The aim of the present study was to detect HPV infection, and clinical and cytological changes in the oropharynx of HIV-positive patients.

Methods

Samples collected from the oropharynx of 100 HIV-positive patients were subjected to hybrid capture (HC), conventional and liquid-based cytology. Clinical data were also collected to investigate the relation with HPV status.

Results

High and low-risk types of HPV were present in 8% and 16.7% of the total sample. The mean ± sd (maximum-minimum) of the relative ratio light unit (RLU)/cutoff (CO) was 2.94 ± 2.58 (1.09–7.87) and 1.61 ± 0.65 (1.07–2.8) for high- and low-risk-HPV, respectively. By cytology, dysplasia was not detected, but atypical squamous cells of undetermined significance (ASC-US) were diagnosed in two samples. No clinical change, suggestive of dysplasia/cancer, was detected.

Conclusion

Our study was able to detect and characterize HPV infection by hybrid capture, which may represent a good tool for screening and follow-up of HPV in the studied population. The frequency and viral load of HPV were low. Neither clinical nor cytological changes suggestive of dysplasia/neoplasia were observed in oropharynx of HIV-positive patients.

Abstract B44: Radiation therapy induced a supra-additive cytotoxic effect in cervical cancer cell line when combined with mTOR inhibitors

The PI3K/AKT/mTOR signaling pathway is frequently activated in HPV-positive squamous cell carcinomas, such as cervical (CC) and head and neck tumors. This study aimed to investigate the biologic effects of mTOR inhibitors associated with radiation therapy (RT) in a cervical cancer cell line (HeLa). A human keratinocytes cell line (HaCaT) was used as control. Temsirolimus, everolimus, resveratrol, curcumin, and epigallocatechin gallate (EGCG) were the mTOR inhibitors used as treatment. MTT cell viability assay was performed to obtain dose-response curves. A nonlinear regression was applied to dose-response curves, in order to calculate the 50% cell cytotoxicity rate (CC50) for each treatment. To evaluate radiosensitization, cells were pretreated with mTOR inhibitors at CC50 followed by RT at 2Gy dose. Mann-Whitney test was used to compare the irradiated and nonirradiated groups. Cell death profile after treatment with temsirolimus, resveratrol, and curcumin was also assessed with flow cytometry. Kruskal-Wallis test with Dunn's post-test was applied on flow cytometry results to compare the control to the treated groups within each cell death profile. Everolimus, temsirolimus, EGCG, resveratrol, and curcumin were cytotoxic to the cervical cancer cell line. The lowest CC50 values after both 24 and 48 hours of treatment were seen in the groups of everolimus with HeLa (28.31 µM and 22 µM, respectively) and temsirolimus with HaCaT (26.54 µM and 12.85 µM). Resveratrol resulted in the highest CC50 values for both cell lines (325.8 µM and 144.6 µM for 24 and 48 hours in HeLa and 355.3 µM and 260.3 µM for 24 and 48 hours in HaCaT). An additive effect was observed when RT was associated with mTOR inhibitors. Cell viability at CC50 for the drug alone and combined to RT were: 64.44% and 33.88% for EGCG; 63.28% and 33.41% for resveratrol; 52.62% and 36.55% for curcumin; 54.06% and 35.04% for temsirolimus; 50.06% and 37.37% for everolimus. These results showed that radiation induced a statistically significant (p &lt; 0.01) supra-additive cytotoxic effect in the cervical cancer cell line when combined with mTOR inhibitors. A Tumor Selectivity Index (TSI) was calculated for each mTOR inhibitor. After a 24-hour treatment, only EGCG and resveratrol were more cytotoxic to HeLa than to HaCaT, with TSIs of 1.41 and 1.09, respectively. After 48 hours of treatment, resveratrol, curcumin, and everolimus were also more cytotoxic to HeLa when compared to HaCaT, with TSIs of 1.8, 3.25, and 3.77, respectively. The TSI results showed that resveratrol was selective for the cancer cell line in both 24 and 48 hours, even though its CC50 was very high. After 24 hours, temsirolimus induced late apoptosis or necrosis in HeLa cells. Based on these data, new studies with mTOR inhibitors as treatment options for cervical cancer are recommended, mainly combined to radiotherapy. Diet-derived mTOR inhibitors may be powerful strategies for the treatment of cervical cancer, particularly if its selectivity for cancer cell lines is confirmed in further studies. Considering the role of HPV oncoproteins and the activation of the PI3K/AKT/mTOR pathway in the pathogenesis of cervical cancer, mTOR inhibitors could be an important therapy in the drug armamentarium for cervical cancer.

Citation Format: Daniele Xavier Assad, Gabriel Alvares Borges, Samuel Avelino, Eliete Neves da Silva Guerra. Radiation therapy induced a supra-additive cytotoxic effect in cervical cancer cell line when combined with mTOR inhibitors [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B44.

Evaluation of immunohistochemical expression of p16 and presence of human papillomavirus in oral and oropharyngeal carcinoma

Carcinogenesis concerns several changes that eventually result in the inactivation of tumor suppressor genes and activation of protooncogenes, leading to loss of cell cycle control. Inactivation of p16 seems to be an early event in this process and occurs in approximately 80% of squamous cell carcinoma cases. The aims of this study were to evaluate the immunohistochemical expression of p16 protein in oral and oropharyngeal squamous cell carcinoma cases, with both the tumoral area itself and its surgical margin being analyzed (dysplastic areas and histologically normal epithelium adjacent to carcinoma), and to verify the presence of human papillomavirus (HPV) and its relation to p16 expression. Paraffin-embedded biopsy tissues from 26 patients, 13 with oral squamous cell carcinoma and 13 with oropharyngeal squamous cell carcinoma, comprised the analyzed samples. To detect HPV, a nested polymerase chain reaction test using PGMY 09/11 and GP5*/GP6* primers and visualization of the product on a 2% agarose gel was performed. Demographic data were obtained from medical records. The results showed low expression of p16 in the tumor area (38.46%), compared with surgical margins in the histologically normal epithelium (84.6%) and dysplastic areas (57.7%). These findings indicate the inactivation of p16 in the process of malignant transformation. The association described in the literature between expression of p16 and presence of HPV could not be verified in this study, because none of the cases was HPV positive.

Expressão imunoistoquímica da ciclina D1 e do p16 em carcinoma epidermóide de boca: correlação com sistema TNM e localização

Objetivo: Avaliar a expressão imunoistoquímica da ciclina D1 e do p16 (proteínas envolvidas nas vias de proliferação celular e utilizadas para determinar o prognóstico de neoplasias malignas) em carcinoma epidermóide de boca. Correlacionar a imunomarcação com o sistema TNM (Tamanho do tumor, presença de linfonodo metastático e metástase à distância) e com sua localização anatômica. Métodos: Trinta e quatro (34) blocos de parafina contendo fragmentos de biópsia incisional de carcinomas epidermóides bucais primários foram obtidos no Hospital Araújo Jorge da Associação de Combate ao Câncer em Goiás. Os dados dos pacientes quanto à localização anatômica e o Sistema TNM foram coletados dos prontuários. A expressão das proteínas ciclina D1 e p16 foi verificada através da técnica imunoistoquímica utilizando a Streptoavidina-Biotina no Laboratório de Patologia Bucal da Faculdade de Odontologia da Universidade de São Paulo (FOUSP). Resultados e Conclusões: Os resultados não revelaram diferença estatisticamente significativa entre o número médio de núcleos positivos para a ciclina D1 e os dados clínicos dos pacientes. Porém, uma menor porcentagem de marcação nos carcinomas de lábio inferior e menor expressão nos tumores classificados clinicamente como T1 foi encontrada. Não houve diferença estatisticamente significativa entre o número médio de núcleos p16 positivos e os dados clínicos dos pacientes com carcinoma epidermóide de boca. Pode-se sugerir que houve um acúmulo nuclear de p16, mas este resultado não tem significância no prognóstico. Entretanto, os resultados da ciclina D1 não mostraram que ela é um marcador absoluto de prognóstico, mas sugerem que o aumento do nível de ciclina D1 contribui junto com outros oncogenes no processo de progressão tumoral.