Soft tissue myxoma of the gingiva: report of a case and review of the literature of soft tissue myxoma in the oral region

Soft tissue myxoma of the oral cavity is extremely rare. We present a case of soft tissue myxoma arising from a mandibular anterior gingiva in a 51-year-old male patient. Histological examination showed islands of odontogenic epithelium scattered in the mucinous stroma. This lesion was supposed to have a odontogenic origin. The clinical differences between soft tissue myxoma with bone destruction and those without bone destruction are also discussed by a review of the literature.     

Nerve sheath myxoma (neurothekeoma) in the tongue of a newborn

Nerve sheath myxoma is a benign peripheral nerve sheath tumor that rarely occurs in the oral cavity; experience with these lesions is therefore limited. The lesion described in this report appeared clinically as a gradually enlarging, painless growth arising on the tongue of a newborn girl. Microscopically, the lesion was characterized by nodules of spindle-shaped cells with abundant myxoid stroma. Immunohistochemical studies were consistent with a nerve sheath neoplasm.     

Nerve sheath myxoma of the gingiva: report of a rare case and review of the literature

BACKGROUND: Nerve sheath myxoma (NSM) is an extremely rare benign neoplasm in the oral cavity. This paper describes the first case, to our knowledge, of NSM in the gingival mucosa of an 84-year-old female patient. METHODS: Intraoral examination revealed a painless and well-defined nodule in the lingual gingival mucosa of the right mandibular lateral incisor, which measured approximately 1.0 cm in diameter. The lesion was fully excised under local anesthesia, without intercurrences. Hematoxylin and eosin staining was performed in 5-microm sections for histopathologic analysis. Immunohistochemical reactions against vimentin and S-100 protein were carried out in 3-microm histologic sections in accordance with manufacturers' instructions. RESULTS: The patient's medical history and an extraoral exam did not reveal other abnormalities. The patient wore a removable partial denture in the affected area. A trauma-induced gingival hyperplasia was the main diagnostic hypothesis. Microscopically, the lesion was composed of an abundant myxoid matrix and stellated and spindle-shaped cells arranged in lobules separated by fine fibrous septa. The cells presented strong positivity for vimentin and S-100 protein. According to the histopathologic and immunohistochemical features, the diagnosis of NSM was established. After 9 months of treatment, no signs or symptoms of recurrences have been observed. CONCLUSION: Although NSM is an extremely rare oral tumor, it should be considered in the clinical differential diagnosis of gingival nodules.     

Oral focal mucinosis: review of the literature and seven additional cases

Oral focal mucinosis (OFM) is a rare, asymptomatic, benign lesion of unknown etiology that usually involves the mandibular gingiva. This article reports on seven patients, six of whom had lesions that involved the gingiva and one that involved the palate. All cases demonstrated the classic lobular, myxomatous mesenchymal tissue with stellate cells. In all cases, immunohistochemical staining for S-100-protein expression was negative, thus excluding the principal differential diagnoses of myxoid neurofibroma and neurothekeoma (nerve sheath myxoma). This article seeks to bring OFM to the attention of clinicians and pathologists who must consider the differential diagnosis of gingival and palatal nodules.     

Peripheral Odontogenic Myxoma: A Review of the Literature and Report of Two Cases

Two cases of peripheral odontogenic myxoma with a verifiable location in gingival soft tissue and without bone involvement were compared with those reported in the literature. This study showed that they form a distinct albeit rare clinical entity with a potential to grow into large disfiguring lesions. The probability that small peripheral odontogenic myxomas are interpreted as edematous irritation fibromas may contribute to the small number of peripheral odontogenic myxomas recorded in the literature. The differential diagnosis of soft tissue myxoid proliferations is discussed.     

牙源性粘液瘤26例分析

目的：探讨牙源性粘液瘤的临床、X线、病理特征及治疗。方法：对26例经病理确诊的牙源性粘液瘤进行分析总结。结果：本组病例男11例,女15例;平均年龄25．9岁;在X线片上多表现为单房或多房的透光阴影;镜下可见大量蓝色粘液样组织及排列疏松的瘤细胞;4例刮治术后复发。结论：牙源性粘液瘤临床症状不典型,影像学表现复杂多样化,常需病理检查确诊。因其具有局部浸润性,手术切除不彻底易复发。     

Gingival metastasis of ovarian carcinoma: report of a case and review of the literature

Diagnosing gingival metastases is difficult because clinically they can mimic benign oral lesions. The authors report an unusual case of metastatic ovarian carcinoma in the gingiva of a 46-year-old woman 5 years after ovariectomy. The tumor presented as an exophytic growth at the molar region of the mandible. Histological examination showed invasive proliferation of atypical glandular structures composed of mucin-producing cells laying in a fibrous stroma. Tumor cells were immunopositive for carcinoembryonic antigen, MUC1 mucin, and lysozyme, while stromal fibroblasts were immunopositive for vimentin and estrogen receptor. The diagnosis of metastatic ovarian mucinous cystadenocarcinoma was made. A review of the English literature revealed this to be the first report of gingival metastasis of an ovarian carcinoma.     

Unexpected diagnosis of an intramuscular myxoma arising from the masseter muscle

Intramuscular myxomas are myxoid neoplasms that mainly affect the muscles of the thigh, upper arm, and gluteus. In the head and neck region they are rare, and we know of only two reported cases in the masseter muscle. We think that this is the third. A 60-year-old woman presented with a painless nodule on the right side of her face. Magnetic resonance imaging showed a well-defined mass restricted to the muscle, with no infiltration into adjacent structures. Microscopic analysis confirmed the gross examination, and showed a tumour with copious myxoid stroma, scattered spindle to stellate cells, and an absence of atypia, which did not stain for CD34, S100, or smooth-muscle actin. A final diagnosis of intramuscular myxoma was made. Despite its rarity, it is important to consider this neoplasm in the differential diagnosis of tumours with a gelatinous-like appearance that involve masticatory muscles of the head and neck.     

Infant Odontogenic Myxoma: A specific entity

IntroductionIn children, and specifically in infants, odontogenic myxomas are extremely rare. In infants, myxoma seems to display mostly the same clinical, radiological and pathological characteristics. This paper presents a series of odontogenic myxomas in infant patients.Materials and methodsFour infant patients were included in this retrospective study. The clinical, radiological and pathological presentation was characterized and the treatment analysed.ResultsAll patients presented with a rapidly evolving paranasal swelling. CT-scan showed a maxillary homogeneous unilocular and intraosseous tumour. In all cases, pathological examination revealed a loose myxoid stroma within stellate and spindle shaped cells. All patients underwent conservative surgery through a vestibular approach.ConclusionThis patient series and a review of the literature demonstrates that odontogenic myxoma is specific in infant. We propose the name of Infant Odontogenic Myxoma for this entity.     

Oral focal mucinosis of the gingiva: case report

BACKGROUND: Oral focal mucinosis is a rare disease of unknown etiology, where the connective tissue undergoes a focal myxoid degeneration. METHODS: We describe a 48-year-old patient who was referred for a firm, tender mass located on the gingiva of the left central mandibular incisor. The first clinical impression at examination was that of a periodontal abscess. RESULTS: The lesion underwent a biopsy, and the final microscopic diagnosis was oral focal mucinosis. CONCLUSIONS: It must be stressed that in most focal gingival lesions, a preoperative diagnosis can be almost impossible.     

Solitary fibrous tumour of the oral cavity: clinicopathological and immunohistochemical characterization of three cases

Solitary fibrous tumour (SFT) is an uncommon mesenchymal neoplasm rarely located in the oral cavity. To characterize further oral SFT, we describe three new cases. Each tumour originated in the buccal mucosa of a middle-aged/elderly patient. Histological examination showed well-circumscribed tumours with densely cellular areas alternating with hypocellular areas in a variedly collagenous, vascular stroma. Mast cells were abundant. The spindle-shaped, neoplastic cells immunostained strongly for CD34 antigen and vimentin and weakly for bcl-2, but not for epithelial cell markers, alpha-smooth muscle actin, or neurofilament or S-100 proteins. Compatible with the virtual absence of mitoses and of marked nuclear atypia, the overall frequency of proliferating cells expressing Ki-67 was low. The expression of CD34 was useful in the differential diagnosis. The consistent location in the cheek and expansion of one tumour after local trauma does not preclude a traumatic element in the development of oral SFT.     

Nerve sheath myxoma (neurothekeoma): a case involving the lip

This case report describes an unusual benign neural tumor involving the lip. It appeared clinically as a gradually enlarging, painless growth arising on the lower lip. Microscopically, it was characterized by whorls of spindle-shaped cells with abundant myxoid cytoplasm and stroma.     

Minocycline-associated intra-oral soft-tissue pigmentation: clinicopathologic correlations and review

BACKGROUND: Intra-oral minocycline staining of alveolar bone and teeth is well-described in the literature. Minocycline-induced discoloration of oral soft tissues is less common and has been often attributed to staining of the underlying bone. AIM: This report documents the clinical and histopathologic features of a case of actual oral soft tissue minocycline-induced pigmentation. The patient, a 45-year-old Caucasian female, presented with pigmentation of the gingiva, lips, and nail beds of recent onset. The past medical history revealed initiation of minocycline therapy 6 months earlier for dermatological concerns. Histopathologic examination of biopsy specimens from the gingiva and lip showed evidence of increased melanin/melanocytes in the epithelium and melanin/melanophages in the connective tissue. A working diagnosis of drug-associated pigmentation was determined and the patient discontinued immediately minocycline therapy. Nine months after cessation of minocycline the patient exhibited a marked reduction in pigmentation. CONCLUSION: Systemic minocycline treatment has the potential to induce significant and esthetically objectionable discoloration of the gingiva and oral mucosa. A brief review of the literature is presented to help understand this uncommon finding that should be included in the differential diagnosis of spontaneous discoloration of intra-oral soft tissues.     

Rhabdomyosarcoma of the maxillary gingiva

BACKGROUND: Rhabdomyosarcoma is a malignant neoplasm of primitive mesenchyme exhibiting skeletal muscle differentiation. Oral rhabdomyosarcoma is rare and accounts for only 0.04% of all head and neck malignancies. METHODS: A 33-year-old woman presented with an erythematous gingival mass involving the anterior maxillary gingiva. The lesion had been present for > or =13 months before presentation, and in recent months, it had become intermittently painful. RESULTS: Clinical examination exhibited erythema and enlargement of the interdental papillae between the left maxillary canine, lateral incisor, and central incisor. The tissue was boggy and tender on palpation. Incisional biopsies were performed, and microscopic examination showed a cellular proliferation of spindle-shaped to ovoid cells with hyperchromatic, enlarged, and pleomorphic nuclei. Many of the tumor cells exhibited abundant eosinophilic cytoplasm. Immunohistochemical stains showed the tumor cells to be positive for desmin, myogenin, and myogenic differentiation 1 (MyoD1). A diagnosis of embryonal rhabdomyosarcoma was made. The patient was treated by surgical resection with postoperative chemotherapy and radiation. The patient had no evidence of disease at a follow-up examination 1 month after completion of therapy. CONCLUSIONS: Oral rhabdomyosarcoma can develop insidiously. Pain is a variable presenting symptom, and early lesions may be mistaken for benign neoplastic, inflammatory, or infectious processes. Over several decades, a multidisciplinary treatment approach that includes surgical removal if resectable, in combination with multiagent chemotherapy and possibly radiation therapy, has improved survival rates.     

Peripheral dentinogenic ghost cell tumor of the gingiva

BACKGROUND: A dentinogenic ghost cell tumor is a locally invasive neoplasm that is characterized by ameloblastoma-like islands of epithelial cells in a mature connective tissue stroma. METHODS: A 43-year-old male patient presented a well-circumscribed sessile, exophytic mass of the gingiva with a diameter of 2 cm located in the canine area of the right maxilla. The lesion was enucleated. RESULTS: The lesion showed odontogenic epithelium, ghost cells, dentinoid material, and giant cells. The final microscopic diagnosis was a dentinogenic ghost cell tumor. CONCLUSIONS: A dentinogenic ghost cell tumor is an extremely rare tumor, and only a few cases have been reported in the English literature. The peripheral, extraosseous lesion can be easily confused with other gingival lesions such as reactive or inflammatory lesions or other peripheral odontogenic tumors. The clinical appearance of all of these lesions is similar; therefore, the definitive diagnosis depends on histology, and a biopsy with a microscopic examination is mandatory.     

Odontogenic myxoma containing osteocement-like spheroid bodies: report of a case with an unusual histopathological feature

The odontogenic myxoma is a rare, benign, but locally invasive tumour of the jaws. Radiographically, it is a bone destroying lesion and has ill-defined borders. Histological characteristics are spindle and stellate-shaped tumour cells and a distinct myxomatous stroma. Bony islands that represent residual trabeculae are found scattered throughout the lesion. This report describes a case of odontogenic myxoma that shows diffusely dispersed osteocement-like spherular calcified bodies, unlike residual bone trabeculae, and discusses its differential diagnosis.     

Bony exostoses developed subsequent to free gingival grafts: case series

Bony exostosis (BE) is described as a benign localised overgrowth of bone of unknown aetiology. Buccal bony exostosis (BBE) development secondary to soft tissue graft procedures has been reported in a small number of cases. The dental literature describes BBE development also at sites where free gingival grafts (FGG) have been used to increase the amount of gingiva. The following case series describes BBE development at nine sites (five cases) at which FGG was performed to increase the width of the attached gingiva. The presence of exostoses has been recognised during postoperative visits. Histological examination revealed osseous enlargements compatible with the diagnosis of exostoses at two re-entry procedures. In conclusion, based on previous reports, periosteal trauma, eg fenestration, seems to be the main aetiologic agent associated with the development of BBE in areas where FGG were placed.     

Myxoid liposarcoma of the oral cavity with involvement of the periodontal tissues

BACKGROUND, AIMS: Liposarcoma is the 2nd most frequent soft tissue sarcoma in adults, but it is extremely rare in the head and neck and, particularly, in the oral cavity. We report on a 25-year-old female who presented with a periodontal mass, extended from the right upper 3rd molar to the right upper 2nd premolar, covered by intact oral mucosa. The clinical differential diagnosis included peripheral giant cell granuloma, salivary gland neoplasms, squamous cell carcinoma of the gingiva, sarcoma and malignant lymphoma. METHODS: To accurately plan subsequent treatment, an excisional biopsy was performed and a myxoid liposarcoma was diagnosed. Consequently, the patient underwent wide excision of the neoplasm with maxillary en-block resection. RESULTS: The post-operative course was uneventful and the patient is alive and well 8 years after the original diagnosis. The authors stress the importance of considering soft tissue sarcomas in the diagnostic approach to patients with unusual periodontal neoplasms and to plan adequate surgical sampling of the lesion (i.e. excisional biopsy). CONCLUSIONS: This appears of pivotal importance as more limited specimens may result in inaccurate pre-operative diagnosis.     

Hepatocellular Carcinoma Metastatic to the Gingiva as a First Manifestation of Hepatocellular Carcinoma

A 55-year-old man consulted to our hospital complaining of a gingival tumor. Oral examination showed granulation tissue-like polypoid tumors (2 × 2 × 1 cm) in the left upper gingiva. A clinical diagnosis of granulation tissue was made, and an incisional biopsy was performed. It showed carcinoma cells in the submucosa. They were arranged in compact and sinusoidal patterns. A few bile plugs and one Mallory-like body were recognized by meticulous examination. An immunohistochemical study showed that the tumor cells were positive for hepatocyte paraffin-1 (HepPar-1), cytokeratins (AE1/3 and CAM6.2), and p53 protein. The carcinoma cells were negative for vimentin, prostate specific antigen, CD10, and α-fetoprotein. The Ki-67 labeling was 49%. A histological diagnosis of hepatocellular carcinoma (HCC) metastatic to the gingiva was made. Then, the patient was referred to hepatology unit. A blood laboratory test showed elevated elevated liver enzymes, and positive antibody to hepatitis C virus. Liver cirrhosis was also present. Imaging modalities including US, CT, and MRI revealed multiple hepatic tumors. Metastases to other sides were not recognized. The patient was diagnosed as cirrhosis and HCC with an extrahepatic metastasis to the gingiva. The patient was now treated by chemotherapy. The present case shows that HCC can manifest as small gingival tumors, and meticulous HE examination and immunoreactive HepPar-1 are useful in the diagnosis of HCC in extrahepatic metastatic sites.     

Collagenous fibroma (desmoplastic fibroblastoma) of the palate: a case report

Collagenous fibroma is an uncommon benign soft tissue lesion that has a wide anatomic distribution. We describe a case of a collagenous fibroma that appeared in the left soft and hard palate of a 37-year-old woman as a 5.0-cm solitary, firm nodule. Microscopically, it was composed of stellate or spindle-shaped cells embedded in hypovascular fibrous stroma. Entrapment of fat was focally identified at the edges. Mitotic figures and tumor necrosis were absent. Tumor cells were immunopositive for vimentin, and a few cells were positive for alpha-smooth muscle actin. Tumor extracellular matrix was immunopositive for type I and type III collagen, as well as for fibronectin. These findings satisfied the diagnostic criteria for collagenous fibroma (desmoplastic fibroblastoma). This case, to our knowledge, represents the first report of this tumor in the mouth. The differential diagnosis of fibrous lesions of the mouth is discussed.