Clinical and demographic features of minor salivary gland tumors: A collaborative study of 480 cases.

OBJECTIVE: To describe the frequency, clinical, and demographic features of minor salivary gland tumors and possible associated factors. MATERIALS AND METHODS: A cross-sectional study was conducted. Clinical and demographic data were collected from biopsy records of two oral pathology services. Chi-square test, Fisher's exact test, and descriptive statistical analysis were performed. RESULTS: A total of 480 (0.89%) minor salivary gland tumors were retrieved, 272 (56.7%) benign and 147 (30.7%) malignant. Sixty-one (12.6%) had no subtype specification. Most patients were women (307/64.0%), in sixth decade of life (80/16.7%), with a mean age of 45.32 years. Palate was the most common site (336/70.1%). Pleomorphic adenoma (PA; 245/51.1%), mucoepidermoid carcinoma (MEC; 70/14.6%), and adenoid cystic carcinoma (ACC; 43/8.9%) were the most frequent tumors. Symptomatic case, recurrence, and tobacco use were associated with malignancy (p < 0.05). PA and MEC were more frequent in palate (p < 0.05). No association between the three most frequent histological types and gender or age group was observed (p > 0.05). CONCLUSIONS: This represents one of the largest exclusive series of minor salivary gland tumors in Brazil and worldwide. PA, MEC, and ACC were the most frequent tumors. Clinical and demographic data are similar from Brazilian studies or from other countries.

Glandular odontogenic cysts: A collaborative investigation of 22 cases and proteins related to invasiveness.

BACKGROUND: A glandular odontogenic cyst (GOC) has an intriguing, aggressive behaviour whose mechanisms have not yet been clarified. OBJECTIVE: To conduct a collaborative cross-sectional study on the clinical, demographic, microscopic and immunohistochemical characteristics of GOCs, emphasizing the histopathological characteristics and expression of proteins related to invasiveness. METHODS: Twenty-two cases of GOC from three oral and maxillofacial pathology services in Brazil were selected from 1988 to 2018. Clinical and demographic data were collected. Histopathological features were evaluated in detail. Sixteen cases of GOC were also submitted to immunohistochemistry to detect MT1-MMP, TKS4, TKS5 and cortactin, the key regulators of invadopodia formation. RESULTS: Glandular odontogenic cysts were primarily seen in men over 40 years of age, in the posterior mandible and the anterior maxilla as a unilocular, radiolucent lesion. All cases presented hobnail cells, clear cells and variable thickness of the lining epithelium, 3 of the 10 key histopathological parameters to be evaluated in GOCs. Immunohistochemistry revealed a greater expression of the studied proteins in the GOCs than in the controls (p < 0.0001). CONCLUSION: Overexpression of proteins that regulate cell invasiveness was identified, and the present study's findings suggest that invadopodia activity is a possible mechanism used by GOCs to promote local invasion, which could partly explain its intriguing biological behaviour.

Clinicopathological and immunohistochemical features of the oral lymphoepithelial cyst: A multicenter study.

BACKGROUND: Analyze the clinical, demographic, histopathological, and immunohistochemical features of oral lymphoepithelial cyst (OLEC). METHODS: Samples were retrospectively retrieved from five oral pathology services. Clinical and demographic data were collected from patient charts. Histopathological and immunohistochemical (CD3 and CD20) features were evaluated. Data analysis involved descriptive statistics and bivariate analyses (P ≤ .05). RESULTS: Seventy-seven cases were found among a total of 146 150 specimens (0.05%). OLEC was predominantly diagnosed in females (70.1%). Mean patient age was 46.51 years. The lesions arose mainly on the lateral border of the tongue (40.3%), measured up to 1 cm (61.0%), and were asymptomatic (64.9%). Twenty-four lesions (31.2%) were white. Forty-one cases (53.2%) presented lymphocytic inflammatory infiltrate with no specific arrangement. The cystic lining was composed of a non-keratinized stratified epithelium (59.7%) presenting hyperplasia (39.0%). Connection with the surface, epithelium was found in 23 cases (29.9%) and 31 (40.3%) cases had two or more cystic cavities. The lumen content was predominantly desquamated cells (48.1%). Subgemmal neurogenous plaque was found in 11/42 (26.2%) cases involving the tongue. CD20+ cells predominated in 36/63 cases (57.2%), and lymphocytic inflammatory infiltrate was not always continuous around the cystic cavity (52.4%). CONCLUSION: Lymphoepithelial cyst is an uncommon lesion of the oral cavity. The present study offers the largest sample of OLEC for which clinical, demographic, histopathological, and immunohistochemical features were evaluated. The clinical and demographic findings were similar to those described in previous reports, but the microscopic analyses revealed interesting aspects of the cystic epithelium and the lymphocytic inflammatory infiltrate in OLEC.

Tumor depth of invasion and prognosis of early-stage oral squamous cell carcinoma: A meta-analysis.

OBJECTIVES: To assess the prognosis for early-stage oral squamous cell carcinoma according to tumor depth of invasion (DOI). METHODS: This study was logged in the PROSPERO database under protocol # CRD42017059976. The search was conducted in six electronic databases up to May 2019. Fixed-effects meta-analysis was performed for the calculation of the odds ratio (OR) and respective 95% CI. Primary outcomes were lymph node metastasis, recurrence, and survival. Heterogeneity was calculated by the I2 test. The certainty of evidence was assessed by Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Twenty-seven studies were included (19 in the meta-analysis) with 2,404 patients with a mean of 60 years of age. High tumor DOI is associated with a greater chance of presenting lymph node metastasis, regardless of the cutoff point for DOI (13 meta-analysis; OR 1.69-53.08), recurrence (five meta-analysis; OR 1.22-3.83), and lower chance of survival (1 meta-analysis; OR 0.49). The certainty of evidence varied from very low to low. CONCLUSIONS: Tumor DOI is a good prognosticator for early-stage OSCC. The findings of the current meta-analysis highlight the clinical relevance of DOI and corroborate its incorporation for staging OSCC.

A Brazilian multicentre study of 2,497 isolated cases of odontogenic keratocysts.

We present the frequency of cases of isolated odontogenic keratocysts submitted to microscopic examination at 10 Brazilian referral centres in Oral and Maxillofacial Pathology. In a retrospective (1953-2017) analysis, data on clinicoradiographic features and treatment of these lesions were collected and analysed descriptively. Among the 258,867 cases retrieved, 2,497 (0.96%) were isolated odontogenic keratocysts. In summary, an overview of individuals affected with isolated odontogenic keratocysts is reported herein. This lesion showed predilection for the posterior mandible of young adult men.

Cell proliferation is associated with intensity of tumor budding in oral squamous cell carcinoma.

BACKGROUND: Tumor budding is a morphological marker of cancer invasion, defined as the presence of isolated or small clusters of neoplastic cells at the tumor invasive front. This study aimed to evaluate the association between intensity of tumor budding and cell proliferation in oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemistry was employed in 163 OSCC samples to detect the cell proliferation marker Ki-67 and multicytokeratin (to identify OSCC cells in tumor budding evaluation). The Mann-Whitney test was used to evaluate differences in the cell proliferation index between samples with high-intensity tumor budding and samples with low-intensity or no tumor budding. In samples with high-intensity tumor budding, the Wilcoxon test was used to evaluate differences in the cell proliferation index between the budding area and the area outside the budding. The chi-square test assessed the association between cell proliferation index and intensity of tumor budding. RESULTS: The cell proliferation index was higher in samples with high-intensity tumor budding than in samples with low-intensity or no tumor budding (P < .05). Tumors with high-intensity tumor budding showed a higher cell proliferation index in the budding area than in the area outside the budding (P < .05). Finally, samples showing high-intensity tumor budding were associated with high cell proliferation index (P < .05). CONCLUSION: Cell proliferation is positively associated with intensity of tumor budding in OSCC. Moreover, in tumors showing high-intensity tumor budding, the budding area is the location of higher cell proliferation. These findings reinforce the hypothesis that tumor budding is associated with the biological behavior of OSCC.

Reproducibility, repeatability, and level of difficulty of two methods for tumor budding evaluation in oral squamous cell carcinoma.

BACKGROUND: This study aimed to analyze the reproducibility, repeatability, and level of difficulty of two methods for tumor budding evaluation in oral squamous cell carcinoma (OSCC): staining by hematoxylin and eosin (HE) and immunostaining for multicytokeratin. METHODS: The evaluation of tumor budding was performed by three examiners in 103 samples of OSCC, using the two methods. A Likert-type scale was used to measure the difficulty in the assessment. The interexaminer agreement (reproducibility) was estimated using Fleiss's kappa and the intra-examiner agreement (repeatability) was estimated using Cohen's kappa. The agreement between the two methods was evaluated using Cohen's Kappa. The Friedman test was used to compare the three examiners' perceived levels of difficulty of assessment. The Wilcoxon test was used to compare the level of difficulty of the evaluation between the two methods. RESULTS: Reproducibility by the immunostaining method for multicytokeratin was substantial, being higher than the only fair agreement by the HE. Repeatability by the HE ranged from moderate to substantial among examiners, regardless of the examiner's experience. Repeatability by the immunostaining method for multicytokeratin did not vary among examiners, showing almost perfect agreement. The agreement between the two methods ranged from fair to moderate among examiners, being lower in the less experienced examiner. All the examiners presented greater difficulty in the evaluation by the HE. CONCLUSION: In view of the unsatisfactory agreement between the two methods of tumor budding evaluation in OSCC, it is recommended that this evaluation should be performed by the immunostaining method for multicytokeratin, considering its higher reproducibility, greater replicability, and lower difficulty compared to the HE.

Laminin-5 gamma 2 chain expression is associated with intensity of tumor budding and density of stromal myofibroblasts in oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers worldwide. Laminin-5 gamma 2 chain (laminin-5 γ2) is a protein associated to a migratory phenotype in epithelial neoplastic cells. Stromal myofibroblasts also play a significant role in tumor invasion, due to its ability to modify the extracellular matrix. Tumor budding is a morphologic marker of tumor invasion. The aim of this study was to evaluate the expression of laminin-5 γ2 in OSCC and its association with intensity of tumor budding and density of stromal myofibroblasts. METHODS: Paraffin-embedded archival samples of 57 OSCC patients were evaluated. Immunohistochemistry was employed to detect laminin-5 γ2, alpha smooth muscle actin (marker of stromal myofibroblasts), and multicytokeratin (to identify OSCC cells in tumor budding evaluation). Laminin-5 γ2 expression and its association with intensity of tumor budding and density of stromal myofibroblasts were analyzed. Association among intensity of tumor budding and density of stromal myofibroblasts was also evaluated. RESULTS: Higher laminin-5 γ2 expression was associated with high-intensity tumor budding (P < 0.05) and with higher density of stromal myofibroblasts (P < 0.05). Moreover, high-intensity tumor budding was associated with higher density of stromal myofibroblasts (P < 0.05). CONCLUSIONS: In OSCC, higher laminin-5 γ2 expression is associated with high-intensity tumor budding and with higher density of stromal myofibroblasts, suggesting that this expression is related to the establishment of an invasive phenotype of neoplastic cells and a permissive environment for tumor invasion in this neoplasia.

Profile of usage of a reference diagnostic service on oral pathology: a 10-year evaluation.

BACKGROUND: Despite the professional and academic relevance of the Brazilian oral pathology diagnostic laboratories, no information about their usage profile is available in the English literature. The objective of the present study is to report data about the histopathological and immunohistochemical exams performed in a Brazilian regional reference laboratory of oral pathology, as well as its main users. METHODS: Information about all histopathological exams performed between 2002 and 2012 was retrieved from the files of the Oral and Maxillofacial Pathology Service of the School of Dentistry of Universidade Federal de Minas Gerais. Data collected included: 1) requestor of exam; 2) diagnosis classification; and 3) immunohistochemical tests. Descriptive statistical analyses were done. RESULTS: 13,522 histopathological exams were performed, mean 1,229/year. The Public Health System of the city of Belo Horizonte was the main requestor of exams (77.13%), followed by private professionals (19.26%), and other cities (2.03%). Most lesions were considered benign (12,599/ 93.17%), with 854 malignant lesions (6.32%). 469 immunohistochemical tests were performed; 324 (69.08%) were from benign diagnosis, and 145 (30.92%) from malignant diagnosis. The most used antibodies were against S100, vimentin, smooth muscle actin, actin muscle specific HHF-35, and pan-cytokeratin AE1/AE3. CONCLUSIONS: Public Health System is the major user of the diagnostic service on oral pathology in our institution. Most diagnoses were of benign lesions, although many malignant lesions were detected. Immunohistochemistry was particularly important in solving challenging cases.

Clinical and demographic overlaps among immunologically mediated oral diseases: a challenge for clinicians.

This study sought to assess and compare retrospective demographic and clinical data of oral lesions of lichen planus, pemphigus vulgaris, and mucous membrane pemphigoid from the records of the Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Brazil, covering a period of 55 years. Out of 25,435 specimens, these immunologically-mediated diseases accounted for 301 (1.18%) cases, of which 250 (0.98%) were lichen planus, 27 (0.11%) were pemphigus vulgaris, and 24 (0.09%) were mucous membrane pemphigoid. Lichen planus presented mainly as white asymptomatic plaques on buccal mucosa. Pemphigus vulgaris was usually characterized by multiple symptomatic erithematous ulcers on the buccal mucosa. Painful ulcers and/or blisters on the gingiva were the most common presentation for mucous membrane pemphigoid. Desquamative gingivitis was noted for all 3 diseases, but mainly for mucous membrane pemphigoid. Overall, lesions were more frequent in white women >50 years. Oral manifestations of immunologically-mediated diseases are relatively rare, and the correct diagnosis can be a challenge for dentists as the lesions often share similar clinical and demographic features.

Subgemmal neurogenous plaque: a series of six cases and a literature overview.

The study aims to describe six subgemmal neurogenous plaque (SNP) cases and compile the previously available data on SNP. Searches on PubMed, Web of Science, Embase, Scopus, and a two-step study selection were performed to compile data from case reports/series of SNP published in English literature. Our six patients (range 29-63 years) had SNP in the posterior lateral border of the tongue. Four of them were associated with lymphoepithelial cysts. A total of 15 studies, comprising 116 patients, were included in this overview. There was a slight predilection for female patients (56.0%) in the 5th (22.4%) and the 7th (23.9%) decades. The lateral border of the tongue (66.4%) was the most common anatomical location. The major manifestation was nodule/papule. Histologically, the presence of taste buds (n = 40/ 34.5%), superficial neural plexus (n = 32/ 27.6%), deep nerve fascicles (n = 32/ 27.6%), ganglion cells (n = 41/ 35.3%), and lymphoid tissue (n = 22/ 19.0%) was mainly reported. Surgical removal was the primary approach, with a low recurrence rate. Although largely unknown, SNP is a regular and likely frequent structure located in the tongue. The findings emphasize the importance of describing clinicopathological patterns of SNP as a differential diagnosis of neural lesions that affect the tongue.

Effects of tobacco on the DNA of smokers and non-smokers affected by OSCC: systematic review and meta-analysis.

Scientific evidence about genetic and molecular changes in oral squamous cell carcinoma (OSCC) among smokers and non-smokers is inconclusive. This systematic review and meta-analysis assessed the effects of tobacco on the DNA of individuals with OSCC based on protein mutations. Electronic searches were conducted on PubMed, Ovid, Web of Science, and Scopus to identify observational studies published up to January/2022. The Joanna Briggs Institute tool was used for the critical appraisal of studies. The certainty of the evidence was evaluated. Twenty-three studies assessing 4,060 individuals (2,967 smokers vs. 1,093 non-smokers) were included in this review. Fifteen groups of proteins/genes were investigated. Analysis of the quality of articles revealed low risk of bias in most studies. The certainty of the evidence was very low. The meta-analysis confirmed no significant difference between smokers and non-smokers with respect to damage to GSTM1 (OR: 0.60; 95%CI: 0.30-1.18), GSTT1 (OR: 1.18; 95%CI:0.49-2.83), hydrolase proteins (Ku70 and Ku80) (OR: 0.74; 95%CI: 0.18-3.05), and transferase proteins (GSTM1, GSTT1, GSTM3) (OR: 0.74; 95%CI: 0.47-1.18). Most of the studies included showed that smokers are more likely to exhibit genetic instability. However, the meta-analysis revealed that smokers do not necessarily have more genetic alterations in the DNA than non-smokers.

Scales to graduate oral mucositis: What are the limitations?

Oral mucositis is a common acute complication of a head and neck squamous cell carcinoma treatment. Multiple scales can be used to diagnose and grade this lesion, but they all have some limitation regarding this group of patients. Most of these issues are associated with the hardness to differentiate signs and symptoms from oral mucositis vs. the inherent neoplasm. This study highlights the importance of a specifically developed scale for patients with head and neck squamous cell carcinoma.

Immunoexpression of Autophagy-Related Proteins in Salivary Gland Tumors: An Exploratory Study.

BACKGROUND: Autophagy is a cellular survival mechanism involved in several human diseases, but its participation in the development of salivary gland tumors is not fully understood. This study investigated the immunoexpression of autophagy-related proteins (autophagy-related 7 [Atg7], microtubule-associated protein 1 light chain 3A [LC3A], microtubule-associated protein 1 light chain 3B [LC3B], protein p62 [p62], and phosphorylated mammalian target of rapamycin [p-mTOR]) in pleomorphic adenoma (PA), polymorphous adenocarcinoma (PAC), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC) of salivary glands. METHODS: Twenty PAs, 20 PACs, 20 MECs, and 14 ACCs were selected. The percentages of cytoplasmic and nuclear positivity for autophagy-related proteins in neoplastic cells were assessed and correlated with histopathological parameters. RESULTS: Cytoplasmic immunoexpression of Atg7 was observed in all groups, with high median percentages of positivity. Regarding LC3A and LC3B, cytoplasmic immunoexpression was found in most PACs (95%) and in all cases of PA, MEC and ACC, with the highest percentages of positivity in PACs and PAs (p < 0.005). ACCs exhibited lower cytoplasmic immunoexpression of p-mTOR (p < 0.005) and lower nuclear expression of p62 (p < 0.05) when compared to PAs, PACs and MECs. Low nuclear immunoexpression of Atg7, LC3A and p-mTOR and absence of nuclear staining for LC3B were observed in all groups. Regarding histopathological parameters of PAs, MECs and ACCs, there were no significant differences in the expression of autophagy-related proteins. In all groups, positive correlations were observed between the immunoexpression of some autophagy-related proteins (p < 0.05). CONCLUSIONS: The results suggest the participation of autophagy in the pathogenesis of PA, PAC, MEC, and ACC of salivary glands. Upregulation of autophagy and reduced nuclear translocation of p62 may contribute to the aggressive biological behavior of salivary gland ACC.

Benign connective and soft-tissue neoplasms of the oral and maxillofacial region: Cross-sectional study of 1066 histopathological specimens.

BACKGROUND: Benign connective and soft-tissue neoplasms (CSTNs) are unusual in the head and neck region. The aim of the present study was to evaluate the demographic and clinicopathological features of these neoplasms. METHODS: A cross-sectional study was conducted of cases diagnosed as benign CSTNs, with data collected from biopsy records. The chi-square test was used. A p-value <0.05 was considered indicative of statistical significance. RESULTS: Among the 38 119 specimens, 1066 (2.79%) were benign CSTNs: 369 fibroblastic/myofibroblastic, 250 adipocytic, 179 vascular, 130 neural, 94 osseous/cartilaginous, 19 muscular, and two fibrohistiocytic. Most patients were female (62.8%) and white-skinned (45.8%). Mean age was 42 years. The tongue (25.2%) was the most affected site for extraosseous neoplasms. CONCLUSION: This study had the largest sample of benign oral and maxillofacial CSTNs. Although these tumors have similar clinical features, the characterization and differentiation detailed here may help clinicians with regards to the correct diagnosis.

Tobacco use increase the number of aneuploid nuclei in the clinically healthy oral epithelium.

BACKGROUND: The most important risk factor linked to the development of oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) is tobacco use. Tobacco contains carcinogens that influence the DNA repair, cell cycle control and may produce chromosomal aberrations. The loss or acquisition of one or more chromosomes is defined as aneuploidy. METHODS: Aneuploidy was determined by means of the DNA-content included in cells obtained by exfoliative cytology and Feulgen's staining. The cells were collected from the clinically healthy lateral margin of the tongue of non-smokers without oral lesions, smokers without oral lesions, smokers with OL, and smokers with OSCC, using the CytoBrush(®). Each group was composed of 20 individuals. A Carl Zeiss image analyzer system and the KS300 software were used. Statistical analysis was performed with BioEstat(®) software. RESULTS: The mean percentage of aneuploid nuclei was statistically higher in the smokers (79.65%), smokers with OL (68.4%), and smokers with OSCC (93.65%), as compared to non-smokers (39.3%) (P<0.05). A trend toward an increase in the aneuploidy of the smokers with OSCC group (P=0.02), as compared to the non-smoker group, could be observed. No significant difference could be observed as regards the mean percentage of aneuploid nuclei in relation to duration of tobacco use or the number of the cigarettes smoked. CONCLUSIONS: Tobacco use is responsible for an increased number of aneuploid nuclei in the oral epithelium.

Can morphological features evaluated in oral cancer biopsies influence in decision-making? A preliminary study.

Tumor budding (TB) is a promising prognostic marker in many cancers including oral squamous cell carcinoma. The evaluation of TB in preoperative diagnostic biopsies has been proven be possible; therefore, the association of TB with other morphological features can represent an important aid in the previous treatment decision. This study aims to evaluate TB in oral squamous cell carcinoma (OSCC) biopsies, assessing its association with other morphological characteristics of the sample. A total of 56 cases of OSCC were investigated. In hematoxylin and eosin-stained slides, morphological features including histopathological grading and mode of invasion were evaluated in the deep invasive front. Moreover, immunohistochemistry was performed with anti-multi-cytokeratin antibody helping in the identification of TB, which was graded as low-intensity or no TB and high-intensity TB. Descriptive and bivariate analyses were performed, and the level of significance was set at 5%. The tongue was the most-affected site with 29 (51.7 %) tumors. The predominant mode of invasion (27-48.2 %) was by groups of neoplastic cells without clear boundaries. Of the cases investigated, 37 (66.1 %) were high-intensity TB, which was associated with the mode of invasion of the tumors (p < 0.05). All cases with the worst mode of invasion showed high-intensity TB. Preliminary results showed the potential of morphological features, such as TB and mode of invasion, evaluated in diagnostic specimens of OSCC, aiding in the treatment decision to select patients who could benefit from more-aggressive treatments.

Epithelioid rhabdomyosarcoma: Report of the first case in the jaw.

OBJECTIVES: Epithelioid rhabdomyosarcoma (EpiRMS) is a novel morphologically distinct variant of rhabdomyosarcoma, with an unusually challenging microscopic diagnosis. The occurrence of rhabdomyosarcomas in the jaws is extremely rare. This study presents the first case of EpiRMS in the jaw (mandible) and a literature review of the previous 35 cases of EpiRMS. STUDY DESIGN: Here, we report a case of EpiRMS affecting an 18-year-old male patient. Clinical, imaging, microscopic, and immunohistochemical features are discussed and previously reported cases of EpiRMS are reviewed. RESULTS: An 18-year-old male patient presented with an exophytic sessile growth on the buccal gingiva, and orthopantomography revealed irregular bone loss. Microscopic analysis showed a large number of cells with epithelioid appearance. Immunohistochemistry staining was positive for desmin, myogenin, MyoD1, smooth muscle actin, h-caldesmon, INI-1, and AE1-AE3. The patient's disease was staged as T4aN1M0 and was treated with surgical excision combined with chemotherapy. CONCLUSIONS: The occurrence of RMS in the mandible is rare, and this is the first case of EpiRMS in the jaw. EpiRMS is an unusual histologic subtype that mimics other sarcomas and epithelial malignancies, making diagnosis a challenge. A specific immunohistochemistry panel aids in the diagnosis. EpiRMS has an aggressive course and an unfavorable prognosis.

A Retrospective Brazilian Multicenter Study of Biopsies at the Periapical Area: Identification of Cases of Nonendodontic Periapical Lesions.

INTRODUCTION: The purpose of this study was to analyze the features of lesions obtained from biopsies at the periapical area of teeth with a radiographic or clinical initial diagnosis of apical periodontitis. METHODS: A retrospective study was conducted on biopsies obtained from 1953-2018 at 3 Brazilian oral and maxillofacial pathology centers. Cases of endodontic and nonendodontic periapical lesions (NPLs) with a clinical diagnosis of endodontic pathoses were retrieved. Data regarding patient age, sex, and anatomic location were obtained from patients' records. The frequency and percentage of cases with clinical diagnoses of a periapical cyst, periapical granuloma, or dentoalveolar abscess were recorded, and the final histopathologic diagnosis was documented. RESULTS: Among 66,179 oral biopsies, 7246 (10.94%) were clinically diagnosed as periapical disease, 306 (4.22%) of which were histopathologically diagnosed as NPLs. The most frequent NPLs were odontogenic keratocysts (n = 107, 34.96%) followed by dentigerous cysts (n = 48, 15.68%). The mean age at diagnosis was 39.68 years with a range of 6-80 years. A total of 159 (51.96%) cases occurred in females and 147 (48.03%) in males (female to male ratio = 1.08:1). Most lesions (137, 44.77%) were located in the posterior mandible. CONCLUSIONS: A wide variety of histopathologic diagnoses, including benign odontogenic and nonodontogenic cystic and tumorous lesions, infectious diseases, and malignant neoplasms, was reported in the present survey. The features presented in this study were consistent with previous findings reported in the literature.