Melanoacanthoma, Plasma Cell Cheilitis and Langerhans Cell Hyperplasia on the Lower Lip: An Unusual Association and Immunohistochemical Analysis.

Oral melanoacanthoma is an uncommon reactive lesion, characterized by basal and prickle cell keratinocyte proliferation surrounded by pigment-laden dendritic melanocytes. Plasma cell cheilitis (PCC) is an inflammatory disorder of unknown aetiology, microscopically presenting a dense plasma cell infiltrate. Most PCC cases affect the lower lip. Langerhans cell hyperplasia (LCHyp), a non-neoplastic counterpart of the LC proliferations, has been reported in association with chronic inflammatory skin diseases. Here, we present an unusual association of melanoacanthoma, PCC and LCHyp on the lower lip in a 59-old-year male, expanding the clinicopathological spectrum of these uncommon lesions. The dendritic melanocytes were highlighted by Fontana-Masson stain and HMB-45, whereas S100, CD1a and CD207 evidenced numerous LCs. MUM1/IRF4, EMA, and CD138 highlighted sheets of polyclonal plasma cells, with an IgG4+/IgG+ ratio of 24%. FTA-ABS test for syphilis was negative.

Exuberant hypercementosis mimicking cementoblastoma / Hipercementose exuberante simulando cementoblastoma

RESUMEN La hipercementosis se clasifica como una proliferación no neoplásica que implica un depósito excesivo de cemento a lo largo del cemento radicular normal. Presentamos el caso de un paciente masculino de 77 años que acude al dentista por una lesión supurativa en la encía que evoluciona desde hace varios meses. El examen radiográfico mostró una gran área radiopaca involucrando la raíz del diente 46, que estaba completamente rodeada por un área radiolúcida, sugiriendo un cementoblastoma asociado con el proceso infeccioso. El examen histopatológico del diente afectado reveló hipercementosis extensa asociada con inflamación supurativa crónica, además de osteomielitis crónica localizada. Esta presentación es infrecuente y, debido a los hallazgos clínico-patológicos, se propone el término "hipercementitis crónica". Los dentistas, especialmente los patólogos orales y endodoncistas, deben estar tener conocimiento de esta inusual presentación para establecer el diagnóstico correcto.

SMARCB1 (INI-1) and NUT immunoexpression in a large series of head and neck carcinomas in a Brazilian reference center.

BACKGROUND: SMARCB1 (INI-1)-deficient carcinomas and NUT carcinomas are aggressive neoplasms, often affecting the sinonasal region. Not uncommonly, their diagnoses are made retrospectively. METHODS: Through SMARCB1 (INI-1) and NUT immunomarkers, 643 head and neck carcinomas were assessed retrospectively. Moreover, SMARCB1 (INI-1)-deficient and NUT carcinomas were additionally evaluated by immunohistochemistry, as well as in situ hybridization analysis for HPV and EBV. RESULTS: Four SMARCB1 (INI-1)-deficient carcinomas (located in lower lip, soft palate, hypopharynx and vocal cord, this latter high-risk HPV positive) and three NUT carcinomas (all located in oropharynx) were detected, previously diagnosed as nonkeratinizing or moderately differentiated squamous cell carcinoma. All cases showed squamous differentiation. NUT carcinomas than SMARCB1 (INI-1)-deficient carcinomas showed low overall survival rate. CONCLUSION: The current cases expand the clinicopathological spectrum of SMARCB1 (INI-1)-deficient carcinomas and NUT carcinomas. Notably, the diagnosis of these cases is easily reached through immunohistochemistry, with impact on their accurate classification, treatment, and prognosis.

Gingival carcinoma cuniculatum mimicking a reactive/inflammatory process / Carcinoma cuniculado gengival mimetizando um processo inflamatório/reativo

ABSTRACT Carcinoma cuniculatum (CC), a rare variant of oral squamous cell carcinoma, presents well-differentiated neoplastic epithelial cells infiltrating the underlying submucosal or bone tissues, forming the so-called "rabbit burrows" filled with keratin. A 67-year-old female patient was referred complaining of a painless tumoral mass in the left mandibular body, with several months of evolution. Previous history indicated extraction of the teeth #37 and #38 and diagnosis of chronic suppurative osteomyelitis. A deep incisional biopsy revealed CC. Due to its microscopic features, suggesting an inflammatory or reactive process, strict clinicopathological correlation is necessary for the correct diagnosis of CC.

RESUMEN El carcinoma cuniculatum (CC), una variante del carcinoma de células escamosas oral, presenta células epiteliales neoplásicas bien diferenciadas que se infiltran en la submucosa o en el tejido óseo subyacente, formando la llamada "madriguera de conejo", rellenada con queratina. Reportamos el caso de una paciente de 67 años con quejas de una masa tumoral asintomática en el cuerpo mandibular izquierdo con varios meses de evolución. La historia previa apuntó exodoncia de los dientes 37 y 38 y diagnóstico de osteomielitis supurativa crónica. Una biopsia incisional profunda reveló CC. Debido a las características microscópicas, que sugirieron un proceso inflamatorio o reactivo, es necesaria una estrecha correlación clinicopatológica para el diagnóstico correcto del CC.

RESUMO O carcinoma cuniculado (CC), uma rara variante do carcinoma espinocelular oral, apresenta células epiteliais neoplásicas bem diferenciadas que se infiltram na submucosa ou no tecido ósseo subjacente, formando a chamada "toca de coelho", preenchida por queratina. Relatamos o caso de uma paciente de 67 anos que foi encaminhada apresentando uma massa tumoral assintomática no corpo mandibular esquerdo com vários meses de evolução. A história prévia indicou exodontia dos dentes 37 e 38 e diagnóstico de osteomielite supurativa crônica. Uma biópsia incisional profunda revelou CC. Devido às características microscópicas, as quais sugeriram um processo inflamatório ou reativo, é necessário estrita correlação clinicopatológica para o correto diagnóstico do CC.

Young and elderly oral squamous cell carcinoma patients present similar angiogenic profile and predominance of M2 macrophages: Comparative immunohistochemical study.

BACKGROUND: M2 macrophages are often detected in oral squamous cell carcinoma (OSCC), which, influenced by hypoxic conditions, appear to have high angiogenesis-inducing capacity. However, the effects of immunosenescence on tumor-associated macrophages (TAMs) and angiogenesis in OSCC are unknown. METHODS: Fifty-seven OSCCs were divided into 3 groups (I: <40 years [n = 17]; II: 40-65 years [n = 20]; III: >65 years [n = 20]). Immunohistochemistry for CD68 and CD163 (TAMs), and CD34 and D2-40 for microvessel density (MVD), microvessel area (MVA), and total vascular area (TVA) were performed. RESULTS: All groups showed similar clinicopathological and immunohistochemical findings. Similar CD68 and CD163 expression, confirmed a M2 phenotype. MVD, MVA, and TVA were similar, however, with significant predominance of blood vessels. No significant correlation between macrophage and angiogenic markers was observed. CONCLUSIONS: A similar TAM and angiogenesis profile suggests the participation of other mechanisms, instead immunosenescence, in young and elderly OSCC patients.

Low-fat and fat-free spindle cell lipomas in the oral cavity: Immunohistochemical analysis and review of the literature.

The low-fat and fat-free spindle cell lipomas (SCLs) are rare and often mistaken for other benign and malignant morphological mimics, because of the fact that the diagnosis relies on its non-lipogenic component analysis. Here, we report the clinicopathological features of two oral SCLs (low-fat and fat-free variants). Both lesions presented clinically as an asymptomatic nodule, which initially yielded diagnostic difficulties on the morphological analysis alone. One case was diagnosed as low-fat SCL on the lower lip in a 29-year-old man, and the other as fat-free SCL on the buccal mucosa in a 46-year-old man. In both cases, immunohistochemistry showed strong positivity for CD34 and, remarkably, retinoblastoma (Rb) protein was deficient. Mast cell (MC) tryptase and toluidine blue stain highlighted numerous MCs distributed throughout all tumor stroma. Alpha-SMA and desmin were negative. S100 evidenced scarce adipocytes only in the low-fat SCL case. Conservative surgical treatment was performed and no recurrence was noticed in about 2-year of follow-up in both cases. Because of the potential pitfalls, careful morphological analysis of the tumor stroma in the low-fat/fat-free SCL diagnosis, supported by immunohistochemistry (especially CD34, Rb and MC tryptase), is strongly recommended. To the best of our knowledge, these are the first and second cases reported of fat-free and low-fat SCL in the oral cavity.