Ana Carolina Amorim Pellicioli

Epstein-Barr virus (EBV)–associated posttransplant lymphoproliferative disorder appearing as mandibular gingival ulcers

Posttransplant lymphoproliferative disorders (PTLDs) comprise a spectrum of complications that affect immunocompromised patients following hematopoietic stem cell transplantation or solid organ transplantation. Its incidence varies depending on the transplanted organ, occurring in approximately 2.3% of kidney transplantations. A 31-year-old woman was referred to the Dental Clinic of the State University of Western Paraná for evaluation of an oral lesion. Her medical history revealed a previous diagnosis of hypertension, Epstein-Barr virus (EBV) seropositivity, and kidney transplantation 12 years prior. She was under standard immunosuppressive therapy. Intraoral examination identified a gingival necrotic lesion with extension to the posterior right lower alveolar bone. An incisional biopsy was performed. Histologic examination showed lymphocytic proliferation of cells with small and hyperchromatic nuclei, atypical mitosis, and cells with large and pale nuclei showing prominent nucleoli permeating connective tissue, muscle fibers, and adipocytes. Correlation of clinical, histologic, and immunohistochemical findings led to a diagnosis of polymorphic EBV-associated PTLD rich in B and T cells.

Immunosurveillance profile of oral squamous cell carcinoma and oral epithelial dysplasia through dendritic and T-cell analysis

Oral squamous cell carcinomas (OSCCs) can arise from potentially malignant disorders, such as leukoplakia. The immune system plays an important role recognizing tumour precursor cells. However, due to immuno-editing mechanisms cancer cells are able to escape immune system surveillance. OBJECTIVE To evaluate the profile of dendritic (Langerhans and plasmacytoid) and T cells in OSCC and oral epithelial dysplasia (OED) and correlate these findings with clinical data. MATERIALS AND METHODS Fifty cases of OSCC and 48 of OED were immunostained for CD1a and CD83 dendritic Langerhans cells (DLC), CD303 plasmacytoid dendritic cells (pDC) and CD8 followed by quantitative analysis. RESULTS Analysis revealed a significant decrease in the number of mature CD83 DLC in OSCC compared with OED. CD303 positivity was significantly increased in the OSCC group when compared to OED. CD8-positive lymphocytes were significantly decreased in OSCC compared with OED lesions. No statistical correlation was found with clinical data. CONCLUSION The number of mature dendritic cells (DC) was decreased in OSCC compared with OED lesions suggesting that either these cells might have migrated to lymph nodes to present the tumour antigens and activate the immune system or cytokines secreted by the tumour microenvironment are inhibiting the adequate maturation of DLC. The numbers of pDC were significantly increased in the OSCC group compared with the OED group. This suggests they may play an important role in the defence against tumours although it is not clear whether this is promoting or inhibiting malignant progression.

Nodular lesion in the buccal mucosa

A 55-year-old woman showing symptoms of a nodular lesion involving the left buccal mucosa with a history of approximately 5 years sought treatment at our dental clinic. The patient’s medical history revealed diabetes mellitus, hypertension, and arthrosis treated with metformin, enalapril, hydrochlorothiazide, and ibuprofen. The patient reported no alcohol use or tobacco consumption. The extraoral examination revealed no abnormalities. The intraoral examination revealed a single, well-circumscribed, submucosal, nodular lesion covered with normal epithelium, measuring approximately 1.0 centimeter in diameter.