Necrotizing sialometaplasia of the lip simulating squamous cell carcinoma

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.

Necrotizing sialometaplasia of tongue

Necrotizing sialometaplasia, is a benign inflammatory lesion primarily involving the minor salivary glands of the hard palate. The lesion often presents itself as a deep-seated palatal ulcer with clinical and histological features similar to those of a malignant neoplasm. Here we report a case of necrotizing sialometaplasia in a 40-year-old female, present on the lateral border of the tongue, mimicking squamous cell carcinoma, clinically. A correct diagnosis to avoid mutilant surgical treatments is essential, considering that it is a self-limiting disease.

Pseudoneoplastic lesions: general considerations

Pseudoneoplastic lesions ("pseudotumors") can be seen in virtually all anatomic locations. Some organ sites, such as the lungs and skin, are overrepresented for unknown reasons, and the histologic images seen in pseudoneoplastic lesions are partially overlapping in disparate locations. More than occasionally, the degree of histologic likeness to true neoplasms-often malignant ones-is striking. This overview outlines the spectrum of pseudoneoplastic lesions and divides them into etiologic categories, including reparative, developmental, functional (usually endocrine), iatrogenic, infectious, and idiopathic. Side-by-side pictorial comparisons of selected pseudoneoplastic lesions and their neoplastic mimics are included.

Histopathological changes in thyroid tissue after fine needle aspiration biopsy

Fine needle aspiration biopsy (FNAB) is a method that is frequently used in the diagnosis for neoplastic and non-neoplastic thyroid lesions. However, despite the contribution of this method to diagnosis, varying degrees of histopathological alterations in thyroid tissue occur due to the trauma caused by the aspiration needle. In this study, we compared the histopathology of the thyroidectomy specimens obtained by FNAB with the specimens obtained without the use of FNAB. A hundred and fifty thyroidectomy specimens obtained by FNAB were compared histopathologically with 150 thyroidectomy specimens (control group) obtained without a FNAB procedure. The thyroidectomy specimens were evaluated for hemorrhage, fibrosis, siderophagia, vascular thrombosis, vascular proliferation, infarction, granulation tissue, cystic degeneration, papillary hyperplasia, nuclear atypia, mitosis, calcification, vascular invasion, capsular distortion (pseudoinvasion), cholesterol clefts, and the presence of metaplasia. The thyroidectomy specimens obtained by FNAB had rates of hemorrhage, siderophagia, granulation tissue, papillary hyperplasia, fibrosis, calcification, capsular distortion, cholesterol clefts (P<0.001), and vascular thrombosis (P=0.001) that were statistically significantly higher than those obtained without FNAB. However, there were no clinically significant differences between the two groups in terms of vascular proliferation, nuclear atypia, mitosis, infarction, and oncocytic and squamous metaplasia. Alterations in thyroid tissue in association with FNAB show a considerable variation. Some of the alterations make diagnosis difficult, even leading to misdiagnosis in favor of carcinoma. Therefore, a thorough knowledge of possible alterations is essential to the differential diagnosis.

Necrotizing sialometaplasia: literature review and case reports

The authors describe necrotizing sialometaplasia, a benign inflammatory lesion primarily involving the minor salivary glands of the hard palate. The lesion presents itself as a deep-seated palatal ulcer with clinical and histologic features mimicking those of a malignant neoplasm. The lesion is believed to be the result of vascular ischemia initiated by trauma. An incisional biopsy is required to confirm the diagnosis, and the lesion heals by secondary intention within four to 10 weeks.

Necrotizing squamous metaplasia in herpetic tracheitis following prolonged intubation: a lesion similar to necrotizing sialometaplasia

In the last year we have encountered three cases of clinically inapparent herpes simplex virus (HSV) tracheitis in biopsies from patients undergoing tracheostomy following prolonged intubation. The diagnosis was based on finding characteristic inclusion-bodies on haematoxylin and eosin stained sections and was confirmed by immunohistochemical staining of infected cells with antibodies to HSV. A prominent mononuclear infiltrate, originally described in HSV oesophagitis, was recognized in two cases. Diffuse squamous metaplasia of both surface and glandular epithelium adjacent to necrotic ulcerated areas was evident in all three cases. Where extensive, the necrotizing squamous metaplasia of the glandular/ductal component was similar to necrotizing sialometaplasia of salivary glands, and likewise simulated squamous or mucoepidermoid carcinoma.

Necrotizing sialometaplasia

Necrotizing sialometaplasia is a benign self-limiting disorder which can simulate malignancy. We report the third such case of nasal fossa involvement in the literature. The pathology of this condition is discussed.

Necrotizing sialometaplasia. A clinicopathologic study of sixty-nine cases and review of the literature

The clinicopathologic findings in 69 cases of necrotizing sialometaplasia (NS) were analyzed and compared with 115 reported cases of NS in the English-language literature. Data comparing age, sex, race, location, clinical presentation, and possible predisposing factors are summarized. Analysis of the data indicates that NS can occur in a variety of clinical settings and may exhibit a spectrum of histologic features. Recognition of NS, regardless of its clinical or microscopic presentation, is essential to avoid inappropriate or unnecessary treatment for this benign reactive process.

Necrotizing sialometaplasia in the mouth floor secondary to reconstructive surgery for tongue carcinoma

Necrotizing sialometaplasia is a benign inflammatory process, which histologically can mimic squamous cell carcinoma. A 63-year-old man underwent left hemiglossectomy involving transplantation of a myocutaneous flap for squamous cell carcinoma of the tongue. One month after the operation, necrotizing sialometaplasia occurred in the minor salivary gland tissue of the mouth floor, compressed by the necrotic flap. This case is very unusual because of the occurrence of necrotizing sialometaplasia in the floor of the mouth. The etiology of the lesion was considered to be ischemia secondary to compression by the necrotic myocutaneous flap.

Necrotizing sialometaplasia: report of 12 new cases

The clinical and histopathological findings of 12 new cases of necrotizing sialometaplasia are described.

Reaction pattern of xenografted human salivary glands in nude mice. An immunohistological and autoradiographical study

35 specimens of human parotid gland and 37 of submandibular gland were transplanted into athymic nude mice. At distinct time intervals, from 1 day to 8 months the transplants were collected and examined. The transplanted glands were studied by light microscopy, immunohistology and autoradiography. The following changes were detectable: acute injury to the xenograft and inflammatory reaction (day 1-7), regeneration of the transplant and the beginning of adaptation to the "mouse milieu" (day 8-30), completion of adaptation (day 30 and later). The presence of the following substances was analysed: amylase, lactoferrin, secretory component, tissue polypeptide antigen (TPA). Amylase was only detected in the early transplants. Lactoferrin was seen only in the small duct system. TPA was present during all transplantation periods and was quantitatively correlated with the 3H thymidine labeling index. From our observations we can say that the salivary glands show two different reacting compartments: a large and a small duct system. The histogenesis of the xenografts, and the relationships of the changes observed to human salivary gland diseases were discussed.

Necrotizing sialometaplasia of the nasal cavity

A case of necrotizing sialometaplasia involving the mucous membrane of a nasal turbinate is described. Necrotizing sialometaplasia is a benign, self-limited process characterized by necrosis and squamous metaplasia of the salivary or mucous glands. Typically, the lesion manifests as an ulcer of the hard palate. Nonulcerated lesions and involvement of sites other than the hard palate have also been reported. This case appears to be the second reported case of involvement of the nasal cavity by necrotizing sialometaplasia.

Segmental lymph-node infarction after fine-needle aspiration

Wedge-shaped lymphoid depletion and sinus distention is described in the pole of an intramammary lymph node. The origin of the lesion appears to be traumatic venous thrombosis. Topographically the lesion differs from spontaneous venous infarction of lymph nodes, and resembles segmented infarction due to small arterial lesions. The usually localised trauma of fine-needle aspiration appears to account for its distinctive microanatomical distribution.