Dendritic cell subpopulations in carcinoma ex-pleomorphic adenoma: A multicenter study.

OBJECTIVE: Carcinoma ex-pleomorphic adenoma (CEXPA) represents a malignant transformation from a recurrent or primary pleomorphic adenoma (PA), and the immune response may be essential in this process. Therefore, in this study, we aimed to identify and quantify subpopulations of dendritic cells (DCs) in CEXPA, residual PA in CEXPA (rPA), and PA. MATERIALS AND METHODS: A multicenter study was performed collecting salivary gland tumor (SGT) samples from three Oral and Maxillofacial Pathology Centers. A tissue microarray containing 41 samples of CEXPA and 22 samples of PA was included in this study and submitted to immunohistochemical reactions against CD1a, CD83, CD207, and Ki67 antibodies. RESULTS: Both PA and rPA showed a higher quantification of CD207+ and CD83+ cells when compared to CEXPA (p < 0.001 and p < 0.01, respectively). There was also a difference when comparing the cell proliferation index between PA/rPA and CEXPA using the Ki-67 marker (p = 0.043). However, there was no difference in the DC population regarding clinical parameters such as sex, anatomical location, size, and metastases (p > 0.06). CONCLUSIONS: Immunohistochemical profile of DC subpopulations and cell proliferation biomarkers in SGTs can contribute as an important tool in the differentiation of benign and malignant tumors or detection of initial areas with malignant transformation.

Approaches to the diagnosis of secretory carcinoma of the salivary glands: a case series and review.

Secretory carcinoma (SC) is a salivary gland neoplasm included in the latest World Health Organization Classification of Head and Neck Tumours. Its morphologic and immunohistochemical characteristics resemble those of breast secretory carcinoma, and the tumors share the same fusion gene, ETV6::NTRK3. This chromosome translocation can be confirmed through reverse transcription-polymerase chain reaction or located using ETV6 fluorescent in situ hybridization. These techniques are expensive, and few laboratories can carry out molecular analysis. In addition, some of these tumors are related to non-NTRK fusion types and non-ETV6 translocation. Therefore, recognition of the typical histopathologic features of SC is the first step in considering this disease among the diagnostic hypotheses. In this case series, morphologic findings combined with immunohistochemical profiles were sufficient to make the correct diagnosis.

Solitary fibrous tumor arising from the buccal mucosa: diagnostic challenge of a rare entity.

A solitary fibrous tumor (SFT) is an uncommon mesenchymal tumor characterized by spindle cell proliferation that rarely affects the oral cavity. The clinical and histopathologic features of an oral SFT are described for the benefit of dental practitioners who may encounter one of these rare cases. A 25-year-old man presented with a slow-growing swelling in the left buccal mucosa. A painless, exophytic, and well-circumscribed submucosal lesion was detected, and an excisional biopsy was performed. The biopsy specimen was submitted for histologic and immunohistochemical staining and subsequent microscopic analysis. The histopathologic examination revealed variable cellularity areas that included spindle- and star-shaped cell proliferation. These cells were immersed in a collagenized stroma containing branching vessels with a staghorn arrangement. According to immunohistochemical analysis, the tumor was characterized by STAT6, CD34, ß-catenin, and Bcl-2 expression. Diagnosis of oral SFTs is challenging given that their microscopic characteristics can mimic those of malignant mesenchymal neoplasms.

Decreased CD1a + and CD83 + cells in tonsillar squamous cell carcinoma regardless of HPV status.

BACKGROUND: Dendritic cells (DCs) are specialized antigen-presenting cells that play a critical role in the immune response against human papillomavirus (HPV) infection, and represent a therapeutic target in cancer. OBJECTIVE: To identify and quantify DCs in tonsillar squamous cell carcinoma (TSCC) under the influence of HPV infection. METHODOLOGY: CD1a and CD83 antibodies were used to identify immature dendritic cells and mature dendritic cells by immunohistochemistry in 33 primary TSCC and 10 normal tonsils (NTs), respectively. For the TSCC samples, the number of DCs per area was evaluated in the intra- and peritumoral compartments. For the NTs, the quantification of DCs was evaluated in the intra- and peritonsillar compartments. HPV detection methods were determined according to the ASCO Clinical Practice Guidelines from the College of American Pathologists Guideline (2018). RESULTS: There were fewer intratumoral CD1a+ DCs in the HPV-positive and HPV-negative TSCC groups than in the NT group (p<0.05). In the peritumoral compartment, there were fewer CD83+ DCs in the HPV-positive and HPV-negative TSCC groups than in the NT group (p<0.001). The quantification of DCs subtypes showed no statistical differences between HPV-positive and HPV-negative TSCC groups (p>0.137). Patients with HPV-positive TSCC had significantly better overall survival rate than those with HPV-negative TSCC (p=0.004). CONCLUSION: Tumor activity contributes to DC depletion regardless of intralesional HPV positivity. An improved prognosis has been reported in patients with HPV-positive TSCC.

Decreased CD1a + and CD83 + cells in tonsillar squamous cell carcinoma regardless of HPV status

Abstract Dendritic cells (DCs) are specialized antigen-presenting cells that play a critical role in the immune response against human papillomavirus (HPV) infection, and represent a therapeutic target in cancer. Objective: To identify and quantify DCs in tonsillar squamous cell carcinoma (TSCC) under the influence of HPV infection. Methodology: CD1a and CD83 antibodies were used to identify immature dendritic cells and mature dendritic cells by immunohistochemistry in 33 primary TSCC and 10 normal tonsils (NTs), respectively. For the TSCC samples, the number of DCs per area was evaluated in the intra- and peritumoral compartments. For the NTs, the quantification of DCs was evaluated in the intra- and peritonsillar compartments. HPV detection methods were determined according to the ASCO Clinical Practice Guidelines from the College of American Pathologists Guideline (2018). Results: There were fewer intratumoral CD1a+ DCs in the HPV-positive and HPV-negative TSCC groups than in the NT group (p<0.05). In the peritumoral compartment, there were fewer CD83+ DCs in the HPV-positive and HPV-negative TSCC groups than in the NT group (p<0.001). The quantification of DCs subtypes showed no statistical differences between HPV-positive and HPV-negative TSCC groups (p>0.137). Patients with HPV-positive TSCC had significantly better overall survival rate than those with HPV-negative TSCC (p=0.004). Conclusion: Tumor activity contributes to DC depletion regardless of intralesional HPV positivity. An improved prognosis has been reported in patients with HPV-positive TSCC.