Absence of multinucleated giant cell reaction as an indicator of tumor progression in oral tongue squamous cell carcinoma.

PURPOSE: The aim of this study was to evaluate the presence and distribution of multinucleated giant cell (MGC) reactions in 61 cases of OTSCC and to verify the association of this microscopic finding with clinicopathological parameters (gender, age, tumor size/extent, regional lymph node metastasis, distant metastasis, clinical stage, and histopathological grade of malignancy). METHODS: Clinical data were collected from medical records and the histopathological grade of malignancy of OTSCCs was evaluated using the World Health Organization (WHO) grading system. The presence and distribution of MGC reaction in high power fields (HPFs) were evaluated in hematoxylin-eosin-stained histological sections. In all cases containing MGCs, immunohistochemical analysis for CD68 was performed in order to confirm the histiocytic nature of these cells. RESULTS: Twenty-one (34.4%) cases had MGC reactions, with a higher frequency of the focal distribution pattern (57.1%). All MGCs were immunohistochemically positive for CD68. The absence of MGC reaction was significantly associated with regional lymph node metastasis (PR: 2.75; 95% CI 1.05-7.20; p = 0.027), advanced clinical stage (PR: 3.37; 95% CI 1.28-8.85; p = 0.006), and moderately/poorly differentiated tumors (PR: 3.36; 95% CI 1.51-7.48; p = 0.001). No significant associations were observed between the distribution of MGCs and clinicopathological parameters (p > 0.05). CONCLUSION: Taken together, the results of this study suggest that the absence of MGC reaction may represent an indicator of tumor progression in OTSCCs.

Histopathological review of 667 cases of oral mucoceles with emphasis on uncommon histopathological variations.

Mucoceles can occur in the oral cavity, appendix, bladder, paranasal sinuses, and lacrimal sac. In the oral cavity, mucoceles arise from pathological alterations in the minor salivary gland ducts. In this study, we aimed to histologically reevaluate cases of oral mucoceles to identify possible variants. A total of 667 slides containing tissue sections stained with hematoxylin and eosin diagnosed as a phenomenon of mucus extravasation were analyzed under light microscopy by 4 previously trained examiners. In 128 cases (19.1%), 1 or more histopathological changes were identified. Twenty cases (2.9%) exhibited collagenous globular structures compatible with myxoglobulosis. In 30 cases (4.49%), dissociation of collagen fibers after mucin extravasation was observed. Fifty-four cases (8.09%) exhibited papillary synovial metaplasia-like change, and 32 (4.79%) showed a significant reduction in the lumen of the cavity due to large papillae. Twenty cases (2.9%) were compatible with superficial mucoceles, and in 11 cases (1.64%), the foamy macrophages showed an unusual solid arrangement, known as clear cell change. It is essential to recognize the possible histopathological changes in oral mucoceles to avoid diagnostic pitfalls.

Participation of hMLH1, p63, and MDM2 proteins in the pathogenesis of syndromic and nonsyndromic keratocystic odontogenic tumors.

OBJECTIVES: To evaluate the expression of hMLH1, p63, and MDM2 in Gorlin syndrome-associated keratocystic odontogenic tumors (SKOTs) and nonsyndromic keratocystic odontogenic tumors (NSKOTs). STUDY DESIGN: Seventeen primary NSKOTs, 17 SKOTs, and 8 recurrent NSKOTs were analyzed by using immunohistochemistry. RESULTS: No significant differences in the hMLH1, p63, or MDM2 labeling indices were observed between groups (P = .398; P = .232; P = .426, respectively). Higher hMLH1 immunoexpression was found in the basal layer of primary NSKOTs. Most KOTs exhibited p63 immunoexpression in the upper layers of the epithelium. MDM2 immunoexpression was observed in the upper epithelial layers of SKOTs and recurrent NSKOTs. CONCLUSION: It was not possible to correlate the immunoexpression of hMLH1, p63, and MDM2 in SKOTs and primary and recurrent NSKOTs, suggesting that these proteins exert independent effects on the development of these groups of tumors.