Primary melanoma of submandibular gland: case report and literature review of a very rare entity.

BACKGROUND: Cutaneous melanomas account for more than 95% of all cases of primary melanoma, making non-cutaneous primary melanomas truly rare. Cases of primary mucosal melanomas of the oral cavity have been widely described; however, instances of primary melanomas arising from salivary glands have been rarely described. To date, this is only the second case of primary melanoma of the submandibular gland. CASE PRESENTATION: This is a report of a case of a 36-year-old healthy male patient, who was referred to us with the chief complaint of a growing swelling on the left side of his lower jaw. Evaluations revealed an evident facial asymmetry in the frontal view with a firm, non-tender swelling. Initial orthopantomogram did not reveal any alterations in the trabeculation or morphology of the jaws and the surrounding structures. A soft tissue ultrasonography of the left submandibular gland and anterior region of mandible revealed a hypoechoic cystic mass with numerous micro-echoes. Further para-clinical examinations yielded the definitive diagnosis of primary melanoma of the submandibular gland. Moreover, no evidence of distant osteometastasis was observed in whole-body scans. Subsequent surgical management with the approach of excising the submandibular salivary gland and concurrent selective neck dissection was implemented. CONCLUSIONS: This report emphasizes the importance of thorough examination and prompt referral to designated specialists in cases with suspicious behaviors which are unresponsive to treatments. It can be further concluded that melanoma can mimic a range of benign pathologies; therefore, putting it in the list differential diagnosis of similar lesions seems plausible.

Aggressive fibromatosis in the submandibular region of a child.

Aggressive fibromatosis is proliferation of well-differentiated fibroblasts. Submandibular region is rare location for fibromatosis. We report a case of a rapidly growing mass in submandibular region of 5-year-old girl, excised surgically and ascertained to be aggressive fibromatosis on histological examination. Recovery was uneventful, and she was disease-free in 6-month follow-up.

The expression of ACAT1 in oral squamous cell carcinoma and the adjacent pre-tumour tissue.

Background: Altered acetyl CoA acetyltransferase 1 (ACAT1) expression has been reported in diverse cancers. However, the expression of ACAT1 and its prognostic value in oral squamous cell carcinoma (OSCC) has remained unexplored. Materials and methods: In this study, the expression of ACAT1 was analysed by immunohistochemistry (IHC) in 61 OSCC patients and compared between OSCC and adjacent pre-tumour tissue of 21 patients. Results: The expression of ACAT1 in OSCC tumours is heterogeneous between patients. More specifically, 52.38% of the patients show low expression of ACAT1 in both tumour and adjacent pre-tumour tissues, 9.52% of the patients show high expression of ACAT1 in both tumour and adjacent pre-tumour, 19.05% of the patients have high expression of ACAT1 in tumour tissue and low expression of ACAT1 in adjacent pre-tumour tissue and another 19.05% of the patients have low expression of ACAT1 in tumour tissue and high expression of ACAT1 in adjacent pre-tumour tissue. Conclusion: Comparison of ACAT1 expression, one of the key enzymes in the ketone body metabolic pathway, divided OSCC patients into two groups: 1) similar expression and 2) different expression of ACAT1 in tumour and adjacent pre-tumour tissue. No significant association between ACAT1 levels and overall survival was observed.

The Frequency of Human Papillomavirus Positivity in Iranian Patients with Head and Neck Squamous Cell Carcinoma.

BACKGROUND & OBJECTIVE: Human papillomavirus (HPV) has been associated with prognosis in patients with head and neck squamous cell carcinoma (HNSCC). Similar to the global studies, different prevalence rates of this viral infection have been reported in Iran. Therefore, we aimed to report the prevalence of this virus and its significance in HNSCC patients. METHODS: Patients who were referred to the five hospitals of Tehran city from May 2018 to May 2019 were enrolled in this study. All patients were diagnosed with HNSCC based on pathologic study. The pathologic disease staging was defined, and DNAs were extracted from the fresh tissue samples via kits. After polymerase chain reaction (PCR), HPV positive samples were evaluated for determining genotypes and data analysis. RESULTS: Of the 46 patients, three patients (6.5%) showed positive HPV results with the following subtypes: 18 (in two patients), 52 (in three patients), 61 (in two patients), 67, and 73.Comparison of variables between the groups with and without HPV showed a significant difference based on the tumor's lymphatic invasion (P=0.041), peripheral lymph node involvement (P=0.008), and histologic grade (P=0.011), but no statistically significant difference in terms of other variables such as age, primary tumor site, size, pathologic stage, vascular or perineural invasion, metastasis, smoking, and alcohol consumption was found.

Mandibular Metastasis of Silent Papillary Thyroid Carcinoma: A Rare Case Report with Review of the Literature.

Metastasis to the jaws is a rare event; however, it has great importance because it may be the only symptom of an undiagnosed underlying malignancy. Papillary thyroid carcinoma, the commonest histopathologic variant of thyroid cancer, has minimal potential for distant metastasis, and most reported metastatic thyroid carcinomas of the oral cavity have been follicular thyroid carcinoma. The aim of this article is to present a rare case of metastatic papillary thyroid carcinoma, which presented itself as a painless expansion in the anterior region of the mandible in a 56-year-old female, and to review previously published cases of this type of cancer. Reporting rare cases such as this one, together with reviewing previous reports of related rare diseases, will expand the body of knowledge about these uncommon lesions.