Mucoepidermoid carcinoma of the posterior-lateral border of tongue: a rare presentation

Role of p63 in Determining the Histogenesis of Low-Grade Neoplasms versus Cystic Lesion

The biological nature of salivary gland neoplasms and the overlapping characteristics that result from the heterogeneity of the cells of origin make diagnosis difficult. Hence, we intend to present a case of low grade mucoepidermoid carcinoma (MEC) on the palate and to understand the importance of biomarker such as p63 in the early diagnosis of tumor as it also has a role in its histogenesis. A 53-year-old female reported with a unilateral swelling for 3 months on posterolateral palatal region of the right side. Clinical differentials for such palatal swellings include a varied spectrum of lesions such as reactive, benign, and malignant lesions. Based on the incisional and excisional biopsy, histopathological findings and immunohistochemical examination with p63 the case were diagnosed with low grade MEC. The tumor cell differentiation in MEC could be the result of multiplicity of differentiation pathways leading to the formation of various histological patterns. This case report highlights the complexity of salivary gland pathology diagnosis and role of specific tumor marker such as p63 as an early marker for differentiation of salivary gland tumor such as low grade MEC from other cystic lesions occurring on the palate.

Mucoepidermoid carcinoma of the anterior lingual salivary gland: A rare case report

Mucoepidermoid carcinomas (MECs) are rare head and neck malignant tumours that were originally considered to be benign. It has been estimated that ~20% of MECs in the major salivary glands, such as the parotid gland, and 50% in the several minor salivary glands found in the oral cavity, are malignant. The diagnosis of MECs is mainly based on ancillary and immunohistochemistry testing. However, owing to the difficulty in harvesting adequate material for histological examination, the histopathological diagnosis of intraoral MECs may be particularly challenging. We herein report a rare case of an 82-year-old patient who presented to the Department of Oral and Maxillofacial Surgery of Ryukyu University Hospital with complaints of a progressive swelling and pain in the ventral surface of the apex of the tongue. The patient had previously undergone needle biopsy and the histopathological analysis of the tumour suggested a diagnosis of irritation fibroma. To ensure a more accurate histopathological assessment, an incisional biopsy was performed, in addition to the haematological and radiological assessments. Examination of the obtained surgical specimen confirmed low-grade MEC of the anterior lingual gland. The tumour was surgically excised, the patient healed uneventfully and no recurrence was detected on the regular 3-year follow-up. Although MECs are relatively more common in the minor salivary glands of the oral cavity, they are a rare occurrence in the anterior lingual gland. Therefore, adequate histological material should be surgically harvested to perform a complete evaluation of the morphology and cytology of the tumour and ensure the accuracy of diagnosis.

Prognostic analysis and nomogram establishment in patients with mucoepidermoid carcinoma of the tongue: a population-based study using the SEER database

OBJECTIVES

To describe the clinicopathological characteristics and determinants of survival of patients with mucoepidermoid carcinoma (MEC) of the tongue.

METHOD

Retrospective population-based study was conducted using the data of patients diagnosed with MEC of the tongue from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2016.

RESULTS

A total of 200 cases of MEC of the tongue were identified. The cohort was composed of 56.5% females. The mean age at diagnosis was 58.8 years. The base of the tongue was the most common primary site (72.5%). Most cases (80.9%) presented with T1 and T2. Lymph node metastases was present in 40.9% of cases, while distant metastases only observed in 2.2% of cases. Overall survival (OS) at 2, 5, and 10 years was 80.2%, 69.8%, and 52.4%, respectively. 77.5 percent of cases (155/200) underwent surgery, and 66 cases received both surgery and radiation therapy. Patients with post-operative radiation had much longer disease-specific survival (DSS). Advanced T stage, distant metastasis contributed independently to shorter OS, while the use of surgery is an independently favorable prognostic factor for OS. In addition, an OS-specific nomogram was established, and the C-index for OS prediction was 0.74 (95% CI 0.67-0.81).

CONCLUSION

This rare malignancy is associated with a generally favorable prognosis, and T stage, distant metastasis as well as surgical therapy are independent predictors of OS.