Oral mucositis: Current knowledge and future directions

Oral mucositis secondary to head and neck chemoradiation displays a complex molecular pathogenesis involving epithelial and microvascular injury, release of pro-inflammatory cytokines, and host-microbiome communications. These processes lead to oxidative stress and the release of reactive oxygen species that stifle the structural integrity of the oral mucosa, with emergence of erosions and ulcers. The consequences are malnutrition, psychological/psychiatric symptoms, poor quality of life, and occurrence of opportunistic infections. The latter pose a major challenge due to the risk of interruption of anti-neoplastic therapy, tumour recurrence and, ultimately, death. This article aims to present the clinical characteristics, molecular pathogenesis, and an overview of the predisposing factors and current management of oral mucositis. It is anticipated that the future direction of the management of oral mucositis will focus on evidence-based prehabilitation and pre- and per-chemoradiation therapy monitoring.

Oral and oropharyngeal lymphomas: A multi-institutional collaborative study

BACKGROUND

Lymphomas in the oral and oropharyngeal regions are relatively uncommon, and their diagnosis is challenging and complex due to the myriad histopathological subtypes. Herein, we report a large series of oral and oropharyngeal lymphomas and compare our data with the currently available literature.

METHODS

All cases diagnosed as lymphomas affecting the oral and oropharyngeal regions were retrospectively retrieved from seven Brazilian institutions. Clinicodemographic data and histopathological features were evaluated and described, while a comprehensive literature review was undertaken in order to compare our findings.

RESULTS

A total of 304 cases of oral and oropharyngeal lymphomas were obtained, mostly affecting individuals aged 60-69 years (n = 68) with a mean age at diagnosis of 54.2 ± 20.1 years. Males and females were equally affected. Mature B-cell neoplasms (87.2%) were the most common group, followed by mature T- and NK-cell neoplasms (11.2%) and precursor lymphoid neoplasms (1.6%). The most frequent subtypes in each group were diffuse large B-cell lymphomas, not otherwise specified (n = 99), extranodal NK/T-cell lymphomas, nasal type (n = 12), and B-lymphoblastic leukaemia/lymphomas, not otherwise specified (n = 4). The most commonly involved sites were the palate (26.3%), mandible (13%), and maxilla (10.5%).

CONCLUSION

Diffuse large B-cell lymphoma, not otherwise specified, remains the most common subtype of lymphomas in the oral and oropharyngeal region. Older patients are the most affected, with no gender predilection and the palate and jaw are usually affected.

Merkel cell carcinoma of the lower lip: A case report and literature review

Merkel cell carcinoma (MCC) is an aggressive primary cutaneous neuroendocrine carcinoma that predominantly affects the sun-damaged skin of the head and neck region, extremities, and trunk of white older individuals. Microscopically, small to intermediate round blue cells show granular nuclei with a salt-and-pepper chromatin pattern, and are usually positive for epithelial and neuroendocrine markers, particularly for cytokeratin 20 in a perinuclear dot-like staining. The 5-year overall survival rate for individuals with localized MCC is 51% and the most common treatment choice is surgery with adjuvant radiotherapy. As far as we know, 23 cases of MCC of the lips have been reported to date in the English-language literature. We herein contribute by reporting a case of MCC affecting the lower lip of an 81-year-old male patient from Rio de Janeiro, Brazil, which likely represents the first reported case from Latin America. A review of the current literature is also included in an effort to familiarize providers with this rare, but potentially lethal neuroendocrine tumor.

Mature dendritic cell density is affected by smoking habit, lesion size, and epithelial dysplasia in oral leukoplakia samples

OBJECTIVE

To compare the densities of CD1a + immature and CD83+ mature dendritic cells, and inflammatory infiltrate cells between smokers and non-smokers with oral leukoplakia. Parameters associated with malignant transformation were also evaluated.

DESIGN

21 smokers and 23 non-smokers diagnosed with oral leukoplakia were obtained. Densities of inflammatory infiltrate cells were calculated in H&E sections. Immunohistochemistry using anti-CD1a and anti-CD83 was performed and densities were calculated. Comparisons and statistical analyses were performed among the groups and parameters as gender, lesion size, site, and presence of cell dysplasia were analyzed.

RESULTS

A lower density of CD83+ cells was observed in smokers compared to non-smokers (P < 0.05). For samples of smokers, a lower density of CD1a + cells, CD83+ cells, and inflammatory infiltrate cells was observed in samples with <10 mm compared to samples ≥10 mm of diameter (P < 0.05), and a lower density of CD83+ cells was also observed between samples without dysplasia compared to samples with dysplasia (P < 0.05).

CONCLUSION

In oral leukoplakia samples, dendritic cell density decreases in the presence of smoking habit, and increases in larger lesions and with epithelial dysplasia. Smoking habit is an external factor that contribute to alteration of the anti-tumoral immune defense system in lesions of oral leucoplakia, reinforcing that smoking elimination is important to control the development of this disease.

MMP-1 and MMP-8 expression in giant-cell fibroma and inflammatory fibrous hyperplasia

The aim of this study is to compare the immunoexpression of metalloproteinases 1 and 8 in giant-cell fibroma, inflammatory fibrous hyperplasia and normal mucosa. Twenty-two cases of giant-cell fibroma, inflammatory fibrous hyperplasia and oral mucosa (control) each were subjected to immunohistochemistry using anti-metalloproteinase-1 and anti-metalloproteinase-8 antibodies. Eight images of each case were captured and analysed through the a) application of a count grid to count the number of positive neutrophils, macrophages, lymphocytes, plasma cells, fibroblasts and blood vessels to obtain the percentage of staining and b) semi-automated segmentation quantifying the stained area in square micrometres. Statistical tests included ANOVA Two-way, Kruskal Wallis and Games-Howell, with a significance level of 5%. An increased percentage of metalloproteinase-1-immunopositive blood vessels were observed in giant-cell fibroma (26.6±22.4; p=0.02) and inflammatory fibrous hyperplasia (34.3±31.5; p=0.01) compared with the control group (19.6±9.2). No significant differences in inflammatory cells, fibroblasts and total area of metalloproteinase-1 and -8 were noted among the three groups. Metalloproteinase-1 apparently acts within the pathogenesis of giant-cell fibroma and inflammatory fibrous hyperplasia.

Classifications of mandibular canal branching: A review of literature

AIM: To gather existing radiographic classifications of mandibular canals branching, considering the criteria on which these were based.

METHODS: The search for studies on mandibular canals based on imaging exams included literature reviews, epidemiological studies of prevalence, descriptive studies, or case reports. An electronic search in the MEDLINE (OvidSP), PubMed, EMBASE (OvidSP), Web of Science (Thompson Reuters), and Scopus (Elsevier) databases was performed, as well as a manual evaluation of the references of the selected articles. Combinations of key words were placed in each database. No restrictions were imposed regarding the year of publication or language. References collected in duplicate were removed by the authors. A table was drawn up, containing the included studies and respective interest data.

RESULTS: Six classifications of mandibular canals branching were selected for the present literature review. Four were based on two-dimensional radiographic exams, and two were performed based on three-dimensional tomographic exams. Three-dimensional classifications were determined based on the analysis found in the least number of exams, comparatively to two-dimensional studies. The prevalence of mandibular canal branching varied from 0% to 38.75% in the works based on two-dimensional exams, while those found in three-dimensional exams ranged from 15.6% to 65%. The studies were mostly referred to branches that began in the mandibular ramus. Just one classification considered the branches that began in the mandibular body region.

CONCLUSION: Three-dimensional exams appear to be the best method to view mandibular canal branching. Further studies are warranted to determine its true prevalence and questions concerning to associations.

Oral lichenoid lesion: A review of the literature

The oral lichenoid lesion (OLL) is response that occurs on the oral mucosa. The OLL include allergic response to the dental materials, drugs, and on graft-vs-host disease (GVHD). OLL to dental material happen when restorative materials, most commonly amalgam, are in direct contact with the mucosa in sensitized individuals. Medications that produce OLL are oral hypoglycemic agents, angiotensin-converting enzyme inhibitors, and nonsteroidal anti-inflammatory agents. GVHD is a complication in bone marrow transplantation and OLL is a common lesion observed in this disease especially in chronic GVHD. The clinical and histological aspects of OLL are similar to oral lichen planus and turn it difficult to make a differential diagnosis. The purpose of this paper is review about OLL related to the dental materials, drug use and GVHD.

Critical review of topical management of oral hairy leukoplakia

Oral hairy leukoplakia (OHL) is a disease associated with Epstein-Barr virus and human immunodeficiency virus infections. OHL is usually an asymptomatic lesion, but in some cases treatment is recommended to reestablish the normal characteristics of the tongue, to eliminate pathogenic microorganisms, to improve patient comfort and for cosmetic reasons. Proposed treatments for this condition include surgery, systemic antiviral treatment and topical management. Topical treatment is an inexpensive and safe therapy that is easy to apply, noninvasive, free of systemic adverse effects and effective over a long period of time. The aim of this study was to present a review of the literature for topical therapy for OHL. Gentian violet, retinoids, podophyllin, acyclovir and podophyllin associated with topical antiviral drugs were used to treat OHL. Reports with this focus are limited, and since 2010, no new studies have been published that discuss the efficacy of topical treatments for OHL. Podophyllin with acyclovir cream was found to be effective, causing regression of lesions with no recurrences. Additional searches are necessary to provide clinical evidence of topical management effectiveness.

Peripheral calcifying odontogenic cyst: a case report and review of the literature

The peripheral calcifying odontogenic cyst (PCOC) accounts for less than 25% of the cases of calcifying odontogenic cysts and most commonly appears as a nodule on the gingiva. This paper aims to present both a case report of a PCOC located in the left vestibular maxilla as well as a review of the English-language literature. An 11-year-old female patient presented a swelling in the vestibular region of teeth 12 and 13. Periapical and panoramic radiographs demonstrated irregular calcification. Surgical excision was performed. Microscopic examination showed an odontogenic cystic lesion lined by ameloblastoma-like epithelium, containing numerous ghost cells. Areas of calcification associated with ghost cells could also be observed. The patient was diagnosed with PCOC. The patient has been disease-free for 36 months. The review of the cases of PCOC showed 44 well-defined cases. The mean age was of 49.4 years at the time of diagnosis. The reported cases appeared as a painless swelling, with a slight predilection for females, and were more frequently located in the anterior region of the maxilla or mandible. Surgical excision is the treatment of choice, and recurrence is rare.

A review of the nonsurgical treatment of oral leukoplakia

The aim of this paper was to assess the nonsurgical treatment of oral leukoplakia (OL). A medline search from 1983 to 2009 was conducted. The topical or systemic nonsurgical treatments or combination of both was reviewed. The primary outcomes of interest were clinical resolution, malignant transformation, follow-up, and recurrence of OL. Studies showed a rate higher than 50% of clinical resolution with photodynamic therapy, beta-carotene, lycopene, or vitamin A. Few studies reported rates of recurrence from 5 to 67% and of malignant transformation from 8 to 23%. There is a lack of randomized clinical trials that assess the effectiveness of nonsurgical treatment of OL. At this time, randomized controlled trials for nonsurgical treatment of OL demonstrate no evidence of effective treatment in preventing malignant transformation and recurrence. It reinforces that even after clinical resolution, OL should be regularly followed.

Immunohistochemical analysis for CD21, CD35, Caldesmon and S100 protein on dendritic cells types in oral lymphomas

Objective:

Follicular dendritic cells (FDCs) and interdigitating dendritic cells (IDCs) are dendritic cells found in lymphoid follicles, reactive follicles and in lymphomas. The goal of this study was to evaluate the presence and distribution of FDCs and IDCs in oral lymphomas.

Material and Methods:

Immunohistochemistry reactions were applied to 50 oral lymphomas using the antibodies anti-CD21, anti-CD35 and anti-caldesmon to FDCs, and anti-S100 protein to IDCs. Caldesmon+/FDCs and S100+/IDCs were quantified in Imagelab® software.

Results:

FDCs revealed by CD21 and CD35 were positively stained in two cases of diffuse large B-cell lymphoma, one MALT lymphoma, and in one case of mantle cell lymphoma. FDCs were immunopositive to caldesmon in all cases, as well as IDCs to S100 protein. Burkitt lymphoma presented a lower amount of caldesmon+/FDCs and S100+/IDCs than diffuse large B-cell lymphoma and plasmablastic lymphoma of the oral mucosa type.

Conclusions:

The microenvironment determined by neoplastic lymphoid cells in oral lymphomas is responsible by the development and expression of dendritic cells types.