Necrotizing sialometaplasia of the palate associated with angiocentric T-cell lymphoma

Necrotizing sialometaplasia: a malignant masquerade but questionable precancerous lesion, report of four cases

BACKGROUND

Necrotizing sialometaplasia (NSM) is an extremely rare benign lesion with an uncertain pathogenesis. The differential diagnosis of this lesion is challenging due to little familiarity with this entity and histologic similarity with carcinomas, especially mucoepidermoid carcinoma (MEC). The purpose of this study is to raise awareness about NSM, which is often overlooked or misdiagnosed as malignancy in a small biopsy.

METHODS

We reviewed all biopsy materials taken from the oral cavity in a single institution in Korea from 2012 to 2018 and found 4 cases of NSM out of 726. Clinicopathologic characteristics and comparison with other lesions were discussed.

RESULTS

Unlike previous reports, patients in our series were relatively young, and NSM was not related to smoking and not associated with malignancies, although one patient was misdiagnosed with MEC on the basis of the initial biopsy. High-grade squamous dysplasia was observed in one patient; however, all four patients showed excellent prognoses without further management.

CONCLUSIONS

A conservative approach is recommendable for necrotizing lesions of the palate in young adults to avoid unnecessary treatment. However, careful monitoring is also required due to uncertainty of premalignant potential.

Necrotizing Sialometaplasia of the Hard Palate: A Rare Entity of Dilemma on Cytology, Confirmatory on Histopathology

Necrotizing sialometaplasia is a rare, benign reactive necrotizing lesion, involving sites where salivary gland tissue is usually present. The importance of this lesion is that it mimics malignancy clinically leading to treatments ranging from conservative excision to total maxillectomy. Cytologically and histologically also the lesion is often confused with neoplasms. We present a case of a lady with a hard palatal swelling, which was non - ulcerative unlike typical cases of necrotizing sialometaplsia. FNAC features made us strongly suspect a low grade mucoepidermiod carcinoma, following which the swelling was excised. Histopathology came to the rescue, on which the final diagnosis of necrotizing sialometaplasia of the hard palate was made. Necrotizing siaometaplasia is often misdiagnosed by the inexperienced cytologist, with histopathological examination being confirmatory. We also emphasize the fact that lesions like necrotizing sialometaplasia need a high degree of suspicion along with clinical co relation before subjecting the patient to unnecessary surgical procedures.

The clinical, histologic, and treatment spectrum in necrotizing sialometaplasia

OBJECTIVES

The aim of this report was the clinical and histologic characterization of necrotizing sialometaplasia.

STUDY DESIGN

We performed a retrospective case series analysis.

RESULTS

The study included 4 women 29-71 years old. Possible contributing factors (drugs, alcohol abuse, bulimia, smoking, and pancreatic cancer) were identified. Patients presented with unilateral or bilateral rapidly progressing painful palatal ulcers. Necrotic salivary glands and inflammation were universal microscopic features; ductal metaplasia was present in only 1 case. Thrombosis and heavy fungal and bacterial overgrowth were observed in 1 case. In 3 of the cases the lesions healed within 4-6 weeks under conservative supportive care, whereas in 1 case persistent enlargement up to 25 mm diameter was observed. Surgical debridement combined with a palatal guard resulted in complete healing within 12 weeks.

CONCLUSIONS

Significant variations may be observed in both clinical and microscopic manifestations of necrotizing sialometaplasia. Although this disease is considered to be self-limiting in the majority of cases, surgical intervention can be considered in unusually large cases.

CT findings of necrotizing sialometaplasia

An otherwise healthy 56-year-old Caucasian female was referred to the radiology department because of an ulceration of her palatal mucosa. Clinically the lesion was suspected to be malignant and a multislice CT examination of the head and neck region was performed. This revealed an ulcer-like cavity with no tumour-like contrast enhancement. No relevant bone changes or suspicious lymph nodes of the neck were detected. Based on the multislice CT findings, necrotizing sialometaplasia was suspected and the diagnosis was verified histopathologically. This report describes the CT findings of necrotizing sialometaplasia at the ulceration stage.

Necrotizing sialometaplasia of the parotid gland associated with angiocentric T-cell lymphoma: a case report and review of the literature

A very rare case of necrotizing sialometaplasia of the parotid gland associated with angiocentric T-cell lymphoma was described. A 66-year-old male had left neck and pharyngeal masses and biopsy specimen showed a monotonous proliferation of atypical lymphoid cells with massive necrosis in the parotid gland. Angiocentric pattern or vascular invasion by the lymphoid cells was observed and the involved parotid gland exhibited squamous metaplasia of the ducts and acini; necrotizing sialometaplasia. Immunohistochemical analysis revealed a cytotoxic T-cell phenotype of the lymphoid cells (CD3+, CD4-, CD5+, CD8+, CD56-, Granzyme B+, TIA-1+, Perforin-) but in situ hybridization showed no relation to Epstein-Barr virus. Although necrotizing sialometaplasia is relatively rare in the parotid gland, angiocentric T-cell lymphoma should be considered for a causative condition of necrotizing sialometaplasia.

Necrotizing sialometaplasia in a patient who is HIV positive: a case report

Necrotizing sialometaplasia (NS) is a self-limiting, benign, inflammatory disease of the minor salivary glands of the hard palate. The main significance of the NS lesion lies in the fact that it may be mistaken for mucoepidermoid or squamous cell carcinoma. A case report is presented of a patient with NS who was HIV positive; the lesion was located in the minor salivary glands of the hard palate. Clinically, the lesion presented as a deep ulcer with slightly elevated irregular borders and a necrotic base in the hard palate. Histologically, the tissue was characterized by squamous metaplasia of ducts and acini, lobular coagulation necrosis, and pseudoepitheliomatous hyperplasia of the overlying epithelium. The lesion disappeared completely after 2 weeks.