Atypical Presentation of Necrotizing Sialometaplasia of the Hard Palate: A Diagnostic Dilemma.

Necrotizing sialometaplasia refers to a benign, uncommon, and self-limiting inflammatory reaction concerning the salivary gland tissue, which both clinically and histologically may be easily mistaken for mucoepidermoid carcinoma or squamous cell carcinoma. This may cause irrelevant surgical intervention. Minor salivary glands are the most commonly affected salivary gland, with the hard palate being the most usual site. However, it can involve the other areas in which salivary gland tissue is present in the other oral subsites and pharyngeal areas. Due to the lack of knowledge about this entity and its histological similarities with carcinomas, particularly mucoepidermoid carcinoma, the differential diagnosis of this lesion is difficult. Local ischemia is thought to be the primary cause, leading to the pathogenesis of necrotizing sialometaplasia, and the infiltration of local anesthesia following dental procedures at the palatal region is the leading cause.

Non-Ulcerated and Ulcerated Necrotizing Sialometaplasia: Report of an Additional Case and Literature Review.

Necrotizing sialometaplasia (NS) is a rare, self-limiting, necrotizing inflammatory lesion, often involving the minor salivary glands of the palate. NS occurs often in men (60%) older than 45 years. Commonly, it presents as an ulcerative lesion, measuring 1 to 3 cm in diameter, with an evolution time of a few weeks or days, simulating malignancy. However, in some instances, the mucosal surface is intact, thus emphasizing the importance of considering NS in the differential diagnosis of oral ulcerative and non-ulcerative lesions. To date, 12 cases of non-ulcerated NS in the palate have been reported. Here, we report a 50-year-old male patient who presented a non-ulcerated, asymptomatic, nodular swelling 3 months ago, located on the hard palate, clinically suggesting salivary gland tumor or lymphoproliferative disorder. After biopsy, a diagnosis of non-ulcerated NS was established. After 4 weeks, the lesion evolved with complete resolution. After literature review, notably, unlike ulcerated NS, the non-ulcerated NS affected patients a decade younger (33 years vs. 45 years), with marked female predilection (83% vs. 40%) and not uncommon bilateral presentation (33% vs. 10%). NS should be considered in the differential diagnosis of ulcerative and non-ulcerative lesions affecting the palate.

Ulcerative and Inflammatory Lesions of the Oral Mucosa.

Ulcerated and inflammatory lesions of the oral mucosa are not rare. A detailed patient medical and social history including habits and abuses, as well as the duration, location, focality and presence, or lack of local and/or systemic symptoms is critical in establishing a proper diagnosis. This article discusses the clinical presentation, management, and histopathologic characteristics of a variety of ulcerative and inflammatory lesions seen in the oral cavity.

Bilateral Asynchronous Necrotizing Sialometaplasia of the Buccal Mucosa: A Case Report and Literature Review.

Necrotizing sialometaplasia is a rare, benign disease that affects any area containing minor salivary glands. This entity presents a diagnostic difficulty due to its resemblance to malignancy. A unique case of bilateral asynchronous necrotizing sialometaplasia with superinfection secondary to trauma is described in this study. A 19-year-old female presented with bilateral ulcerative lesions in her buccal mucosa and facial swelling. The two lesions appeared several weeks apart. The diagnostic workup excluded rheumatologic, malignant, and infectious etiologies. The patient was treated with antibiotics and steroids with subsequent resolution of symptoms. Given the exclusion of other etiologies, the patient was diagnosed with bilateral asynchronous necrotizing sialometaplasia with superinfection. This case demonstrates the importance of considering necrotizing sialometaplasia as a diagnosis in all patients with oral ulcerative lesions.

A diagnostic error of a necrotizing sialometaplasia: Case report.

INTRODUCTION: Necrotizing sialometaplasia (NSM) is a benign, self-limiting, inflammatory disease of salivary glands, mainly involving the minor salivary glands in the palate. This lesion can mimic a malignant neoplasm, both clinically and histopathologically, manifesting as a submucosal swelling or as an ulcer of the palate. We illustrate our work with a case of necrotizing sialometaplasia misdiagnosed as carcinoma. CASE PRESENTATION: A 26 years old woman presented to dental treatment and consultation center of Rabat, for a rehabilitation of left palatal bone defect with an obturator prothesis. A postsurgical erythematous area was noted at the left palate during intraoral examination. After medical file study, we founded that she had a necrotizing sialometaplasia treated by maxillectomy of the left maxillary bone, and we realized that a diagnostic error was made leading to an aggressive treatment. CLINICAL DISCUSSION: Necrotizing sialometaplasia can be misdiagnosed clinically and microscopically as a malignant neoplasm, resulting in inappropriate and aggressive treatment like the case presented. CONCLUSION: The diagnosis of NSM is challenging, the role of histopathology and immunohistochemistry is of paramount importance.

Necrotizing Sialometaplasia: A Diagnostic Challenge to Oral Physicians.

Necrotizing sialometaplasia is a rare, reactive, self-limiting disorder affecting a minor salivary gland that clinically mimics malignancy. Chronic smoking, alcohol use, trauma to the hard palate caused by local anesthetic injection due to the vasoconstrictive action of adrenaline in local anesthetic, topical application of nonsteroidal anti-inflammatory drugs like flurbiprofen spray used in bronchial asthma, oral intubation procedures for general anesthesia, ill-fitting dentures, bulimia nervosa, and minor salivary gland tumors are some of the contributing factors linked to its development. In this article, we discuss a rare, reactive, self-limiting condition affecting minor salivary gland, necrotizing sialometaplasia that occurred on the right posterolateral hard palate region in a 57-year-old male chronic smoker, diagnosed by oral medicine specialist by clinical findings and radiological evaluation by cone beam computed tomography that healed rapidly in three days by itself without any treatment, that prevented unwanted biopsy or surgery.

Non-ulcerated necrotizing sialometaplasia may mimic a salivary gland tumor.

Necrotizing sialometaplasia (NS) is a benign, self-limiting inflammatory entity that mainly affects the minor salivary glands located in the hard palate. Classically, NS is characterized as a nodule that evolves to a central ulcer. The most widely recognized triggering factor is an ischemic event. The diagnosis becomes a challenge in non-ulcerated NS cases which is essential to rule out the possibility of salivary gland tumors, especially the malignant ones. Here, we presented a case of a 32-year-old male patient with a 1-month complaint of a painful, slightly elevated erythematous area on the hard palate. Incisional biopsy was performed, and NS was diagnosed based on histopathological and immunohistochemical analyses. Clinicians should be aware of and consider NS as a differential diagnosis of minor salivary gland tumors, particularly when it presents as a non-ulcerated clinical aspect.

Non-ulcerated necrotizing sialometaplasia may mimic a salivary gland tumor

Necrotizing sialometaplasia (NS) is a benign, self-limiting inflammatory entity that mainly affects the minor salivary glands located in the hard palate. Classically, NS is characterized as a nodule that evolves to a central ulcer. The most widely recognized triggering factor is an ischemic event. The diagnosis becomes a challenge in non-ulcerated NS cases which is essential to rule out the possibility of salivary gland tumors, especially the malignant ones. Here, we presented a case of a 32-year-old male patient with a 1-month complaint of a painful, slightly elevated erythematous area on the hard palate. Incisional biopsy was performed, and NS was diagnosed based on histopathological and immunohistochemical analyses. Clinicians should be aware of and consider NS as a differential diagnosis of minor salivary gland tumors, particularly when it presents as a non-ulcerated clinical aspect.

[Immunohistochemical diagnosis of necrotizing sialometaplasia]. / Immunogistokhimicheskaya diagnostika nekroticheskoi sialometaplazii.

The article presents a clinical case of an immunohistochemical study of a rare disease: necrotizing sialometaplasia in the hard palate. Due to the complexity of the differential diagnosis between necrotizing sialometaplasia and squamous cell carcinoma, an immunohistochemical method was used with antibodies to proteins Ki-67, P53, P63 and cytokeratins-7 and Immunohistochemical study established low proliferative activity of glandular cells in excretory ducts and metaplastic squamous epithelium for Ki-67 protein, significant expression of protein P63 was detected both in the ductal epithelium nuclei and in metaplastic areas and expression of the mutant protein P53 was approximately absent. Marked expression of cytokeratin-7 in the ducts cells and weak expression in necrotic acini of the glands and metaplastic epithelium was noted. It was shown that cytokeratin-15 homogeneously stains the peripheral zone of metaplastic epithelium, which is characteristic of a benign lesion. Thus, the panel of antibodies to proteins Ki-67, P53 and cytokeratins-7 and 15 allows to verify necrotizing sialometaplasia.

Low-Level Laser Therapy Approach of Bilateral Necrotizing Sialometaplasia of the Hard and Soft Palates.

Introduction: Necrotizing sialometaplasia (NS) is a rare locally destructive inflammatory benign disease that commonly affects the minor salivary glands. It is frequently associated with the glands located in the posterior portion of the hard and soft palates. Low-level laser therapy (LLLT), also called photobiomodulation therapy (PBMT), has been deemed a substantial method for the regenerative wound process. Case Presentation: A 32-year-old male patient was referred with a chief complaint of two asymptomatic crater-like ulcers measuring approximately 1.5 cm wide on the right side of the hard and soft palates, and another measuring 0.3 cm wide on the left side of the hard palate. The lesion had two weeks of evolution followed by a previous infectious "sore throat" event that kept the patient hospitalized for 4 days. A clinical diagnosis of NS was made. LLLT was applied during 2 sessions per week, favoring the total wound healing within 2 weeks. At 3 months of clinical followup, the patient did not present any complication or relapse and was thus released. Conclusion: This is, to our knowledge, the first clinical report of LLLT applied for the management of NS. Large palatal ulcers caused by NS usually have long healing periods. The shortened healing period observed in this case encourages the inclusion of LLLT in any treatment protocol for similar lesions.

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 and Bulimia: A Case Report.

Bulimia is an eating disorder with a great prevalence in young women. Due to its multifactor ethiology, bulimia has systemic consequences. In the literature, necrotising sialometaplasia is seldom associated with bulimia. Its etiopathogenesis is discussed by several authors; nevertheless, the consensus does not consider the relevance of local trauma associated with induced vomiting. A case of necrotising sialomethaplasia, presented with a single hard palatal ulcer in a bulimic woman is described in the present report. The patient did not present significant systemic laboratorial values, nor physical weight variations, which highlights the relevance of performing a complete medical clinical history when diagnosing this rare pathology.

Necrotizing sialometaplasia of the palate in a young bodybuilder with anabolic androgenic steroids abuse.

Necrotizing sialometaplasia is a benign, self-limiting, inflammatory disease of salivary glands, mainly involving the minor salivary glands in the palate. This lesion can mimic a malignant neoplasm, both clinically and histopathologically, manifesting as a submucosal swelling or as an ulcer of the palate. This report presents a case of an otherwise healthy bodybuilder with anabolic androgenic steroids abuse with bilateral necrotizing sialometaplasia in the palate, and discusses computed tomography findings in the pre-ulceration phase. Literature review revealed another two cases of necrotizing sialometaplasia with preoperative imaging, both performed in the ulceration phase. The importance of radiographic findings as an aid in differential diagnosis is further discussed, as well as the role of possible predisposing factors including anabolic androgenic steroids abuse in the pathogenesis of necrotizing sialometaplasia.

Necrotizing Sialometaplasia of the Hypopharynx.

Necrotizing sialometaplasia (NSM) is a benign, reactive metaplastic condition of the minor salivary gland tissue typically seen in the setting of injury, chemical or traumatic, and is nonneoplastic and self-limited. The diagnosis may be challenging as it may clinically mimic malignancy. We present the case of a 74-year-old male with a 1 pack per day smoking history for 60 years who presented with a reported 20-pound weight loss, dysphagia, and dysphonia progressing over the course of 6 months and found to have a 3.5-cm hypopharyngeal mass on computed tomography imaging and fiberoptic laryngoscopy. Initial frozen section of the mass was concerning for squamous cell carcinoma in situ, but permanent specimens returned as nondiagnostic. Repeat biopsy established a diagnosis of NSM. Two-month follow-up showed complete resolution of the mass. Clinicians should be aware that NSM may present in unusual locations when considering differential diagnoses for laryngeal masses and evaluating for malignancy.

Necrotizing sialometaplasia can hide the presence of salivary gland tumors: A case series.

OBJECTIVE: Necrotizing sialometaplasia (NS) is an uncommon benign process which affects minor and, more rarely, major salivary glands. While self-limiting, the condition might be clinically and histologically mistaken for malignancy. Furthermore, NS may accompany neoplasms. The aim of this paper was to report a series of Italian patients affected by NS associated with an unusual high presence of neoplasms of minor and major salivary glands. STUDY DESIGN: Clinical and histological features of twelve patients with NS were retrospectively evaluated. RESULTS: Eight patients presented NS of the minor salivary glands of the palate, and two of them had associated neoplasms (pleomorphic adenoma and adenoid cystic carcinoma) at the same site. Four patients had NS of the parotid gland associated with a history of fine-needle aspiration biopsy performed to diagnose parotid neoplasms. These were epithelial-myoepithelial carcinoma, adenoid cystic carcinoma, Warthin's tumor, and oncocytoma, respectively. CONCLUSION: Tumors of minor and major salivary glands might be associated with NS more frequently than previously reported. While NS of the parotid is generally the result of invasive diagnostic procedure and is detected after the excision of the tumor, NS of the minor salivary glands may obscure an underlying neoplasm, resulting in delays in referral or treatment.

Infarcted Warthin tumor with mucoepidermoid carcinoma-like metaplasia: a case report and review of the literature.

BACKGROUND: Warthin tumor is a common, benign, painless salivary gland neoplasm. Rarely, Warthin tumors show large areas of squamous metaplasia; such Warthin tumors are called metaplastic or infarcted Warthin tumors because they are occasionally accompanied with tumor necrosis. The histological distinction between mucoepidermoid carcinomas and the metaplastic portions of Warthin tumors can be challenging; without a genetic study, mucoepidermoid carcinomas can be misdiagnosed as metaplastic Warthin tumors. We report a case of infarcted Warthin tumor partly showing mucoepidermoid carcinoma-like epithelial metaplasia. Only two cases of infarcted Warthin tumor similar to our case have been reported. CASE PRESENTATION: A 69-year-old Japanese man presented with a right parotid tumor. He had noticed the swelling on his right buccal region 1 year previously; the lesion had rapidly enlarged, with associated pain, 1 month previously. A radiological examination revealed a mass in the tail of the right parotid gland. Superficial parotidectomy was performed. On histological examination, the mass showed typical focal features of Warthin tumor; other areas showed coagulation necrosis of the tumor. These areas were surrounded by non-oncocytic epithelium comprising squamous and mucinous epithelial cells. Although cellular atypia of the non-oncocytic epithelium was not observed, a mixture of squamous and mucinous cells and lack of abundant lymphoid tissue mimicked low-grade mucoepidermoid carcinoma. Based on the results of fluorescence in situ hybridization, MAML2 gene rearrangement was not present in the typical portions of Warthin tumor and the mucoepidermoid carcinoma-like lesion. Therefore, a metaplastic or infarcted Warthin tumor was diagnosed. Our patient was disease-free 8 months after surgery. CONCLUSIONS: Clinicians need to know that pain is a clinical symptom of infarcted/metaplastic Warthin tumor. Pathologists should be aware that a metaplastic Warthin tumor can mimic a low-grade mucoepidermoid carcinoma. Our case showed a mucoepidermoid carcinoma-like lesion that was confined near the area of tumor necrosis, and neither cytological atypia nor apparent invasive growth was present. These findings appeared to be histological clues of a metaplastic Warthin tumor rather than a mucoepidermoid carcinoma. Careful clinicopathological evaluation as well as genetic studies are needed to clarify the distinction between mucoepidermoid carcinoma and metaplastic portions of Warthin tumors.

Sialometaplasia Necrotizante: Revisión de la Literatura a Propósito de un Caso / Necroting Sialometaplasia: Review of the Literature on a Case

RESUMEN: La sialometaplasia necrotizante (SN) es una rara enfermedad benigna, inflamatoria, autolimitante, que afecta más frecuentemente a las glándulas salivales menores y que comúnmente se asocia a las ubicadas en la porción más posterior del paladar duro. Su etiología no esta clara, la mayoría de los autores sugieren que una lesión química, física o biológica de los vasos sanguíneos produciría cambios isquémicos, que provocarían infarto del tejido glandular con necrosis, inflamación e intento de reparación. Clínicamente puede presentarse como una úlcera de márgenes irregulares, ligeramente elevados y lecho necrótico, mientras que histopatológicamente se caracteriza por presentar metaplasia escamosa de conductos y acinos e hiperplasia pseudoepiteliomatosa del epitelio mucoso. La similitud de sus características clínicas e histopatológicas con algunas lesiones glandulares malignas de la cavidad oral, puede resultar en tratamientos innecesarios, considerando que la SN se trata de una patología autoresolutiva, por lo que es fundamental realizar un correcto diagnóstico clínico e histopatológico para evitar tratamientos quirúrgicos mutilantes o innecesarios. En el presente trabajo se presenta un caso de una mujer joven, con diagnóstico de SN, con sus características clínicas, histopatológicas y la evolución de la lesión.

ABSTRACT: The Necrotizing Sialometaplazia (NS) it's a rare self-limiting, inflammatory, benign disease, that most frequently affects the minor salivary glands and it is commonly associated to the glands located at the most posterior portion of the hard palate. Its etiology is not clear. Most authors suggest that a chemical, physical or biological lesion of the blood vessels would produce ischemic changes, which lead to infarction of muscle tissue with necrosis, inflammation and attempts to repair. Clinically it can present as a slightly elevated ulcer with irregular edges and necrotic bed, while histopathologically it is characterized for present squamous metaplasia of ducts and acini and pseudoepitheliomatous hyperplasia of mucosal epithelium. The similarity of its clinical and histopathological characteristics with some malignant glandular lesions of the oral cavity, can result in unnecessary treatments, considering that NS is a self-sustaining pathology, it is therefore essential to perform a correct clinical and histopathological diagnosis to avoid mutilating or unnecessary surgical treatments. In the present work we present the case of a young woman, with diagnosis of NS, with its clinical and histopathological characteristics and the evolution of the lesion.

Necrotizing sialometaplasia of the parotid gland associated with facial nerve paralysis.

INTRODUCTION: Necrotizing sialometaplasia is a benign inflammatory lesion involving most frequently the minor salivary gland of the hard palate. Involvement of the parotid gland is rare, involvement of the parotid gland associated with facial palsy is exceptional. CASE REPORT: A 56-year-old male patient with Marfan syndrome presented with swelling and inflammation of the left parotid gland associated with progressively complete facial nerve paralysis. CT scan and MRI showed a parotid collection with hyper signal of the nearest tissues associated with erosion of the styloid process. A malignant tumor was suspected. The histological examination of a biopsy showed a lobulocentric process with necrosis, squamous metaplasia, and inflammation. The immunohistochemical examination supported a final diagnosis of necrotizing sialometaplasia. DISCUSSION: Necrotizing sialometaplasia of the parotid gland associated with facial nerve paralysis presents like a malignant neoplasm, both clinically and histologically. Only advanced immunohistochemical examination can really confirm the diagnosis.

Necrotizing sialometaplasia of the lacrimal sac mimicking squamous cell carcinoma: Necrotizing dacyocystometaplasia.

INTRODUCTION: Necrotizing sialometaplasia is thought to represent an inflammatory reaction directed against an ischemic insult or local trauma within a glandular tissue and is most commonly observed in the minor salivary glands of the oral mucosa. The importance of this condition arises from the fact that its clinical and histological aspects may raise issues of differential diagnosis with malignant neoplasms. The authors present a case of necrotizing sialometaplasia involving the lacrimal sac simulating a well-differentiated squamous cell carcinoma. CASE: A 52-year-old man presented with epiphora in the left eye after having sustained an orbital blowout fracture during a motor vehicle accident. During subsequent external dacryocystorhinostomy, an abnormal lacrimal sac mucosa was observed and analyzed histologically revealing a well-differentiated squamous cell carcinoma. However, the subsequent biopsies of the lacrimal sac were negative for malignancy; in view of these findings, two pathologists reviewed the first specimen and immunohistochemical staining was performed allowing us to arrive at a diagnosis of necrotizing sialometaplasia. We suggest the term necrotizing dacryocystometaplasia for the involvement at this site. CONCLUSION: Although exceedingly unusual, necrotizing dacryocystomeplasia should be considered in patients presenting with epiphora in the appropriate clinical context. Notably, this condition can be mistaken for a malignant disease, presenting a diagnostic challenge both clinically and histopathologically.