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C H Siar

Publications and source records attributed to C H Siar.

At least 19 recordsLinked to original sources
PubMed1992

Immunohistochemical study of the distribution of S-100 protein in pleomorphic adenomas of minor salivary glands.

Twelve pleomorphic adenomas of minor salivary gland origin were examined for the distribution of S-100 protein, detected using the peroxidase-antiperoxidase (PAP) method. Strong S-100 protein immunoreactivity was noted in areas containing plasmacytoid cells, stellate and spindle cells against a myxochondroid or hyalinous stroma, and solid epithelial areas. Tubular and duct-like structures showed variable stainability. Stromal tissue and normal salivary glands were generally negative for S-100 protein. These findings were compared with those reported elsewhere.

Adenoma, Pleomorphic↗
PubMed1992

Denture hyperplasia and oncocytic metaplasia.

A case of denture hyperplasia of the upper labial sulcus with concomitant oncocytic metaplastic changes is described. The patient concerned is an elderly male wearing an ill-fitting upper full denture.

Aged↗
PubMed1992

Leiomyoma of the incisive papilla region: a case report.

Leiomyomas are benign neoplasms of smooth muscle origin. They represent rare entities in the oral cavity. A case arising from the incisive papilla region of a 3-month-old infant is described and the histogenesis as well as the biologic potential of this tumor are discussed.

Diagnosis, Differential↗
PubMed1991

Nasofacial zygomycosis.

Zygomycosis is an uncommon polymorphic fungal disease. One clinical subtype, nasofacial zygomycosis, is caused by infectious exposure to the organism Conidiobolus coronatus. A case affecting the nose and lips of a 42-year-old Malay man is reported here. The clinicopathologic features and management of this disease are described, and its differential diagnosis is discussed.

Adult↗
PubMed1991

Plexiform granular cell odontogenic tumor: unicystic variant.

Plexiform granular cell odontogenic tumor of the mandible has recently been described. The cardinal histopathologic feature, as its name suggests, is a monophasic plexiform pattern of granular cells; the principal tumor in the differential diagnosis is granular cell ameloblastoma. Unlike the two previously reported cases of plexiform granular cell odontogenic tumor, which occurred as solid tumors in elderly men, the lesion reported here is a unicystic variant occurring in a middle-aged woman.

Cell Nucleus↗
PubMed1991

The combined epithelial odontogenic tumour in Malaysians.

The combined epithelial odontogenic tumour represents a hybrid lesion comprising primarily areas of adenomatoid odontogenic tumour intermixed with foci of calcifying epithelial odontogenic tumour. Five such cases retrieved from the files of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, and four others from the existing literature were analysed. A mean age of 18.8 years, a female preponderance (66.7%) with a male to female ratio of 1:2 and predilection for the mandible (55.6%) were observed. All cases were treated by conservative surgery and the lack of recurrence confirmed the innocuous nature of this lesion.

Adolescent↗
PubMed1991

Calcifying and keratinizing ameloblastoma of the maxilla.

A case is described of ameloblastoma of maxilla presenting with numerous calcified keratin pearls. The significance of cellular variation in relation to the behavioural potential of the ameloblastoma in general is briefly discussed.

Adult↗
PubMed1991

Kimura's disease: a case report.

The clinical and histologic features of Kimura's disease are briefly outlined. A case presenting as a subcutaneous nodule in the region of the angle of the right mandible of a 20-year-old male is presented. The relationship of this disease to angiolymphoid hyperplasia with eosinophilia is discussed.

Adult↗
PubMed1990

Peripheral ameloblastoma with clear cell differentiation.

This report details a case of mandibular peripheral ameloblastoma having a clear cell component. The latter consisted of ovoid cells with vacuolated or clear cytoplasm and vesicular or pyknotic nuclei that may be disposed as discrete clusters or show direct transition from typical acanthomatous areas. Comparison of this lesion with other odontogenic and nonodontogenic tumors that contain clear cells is discussed in the context of the differential diagnosis.

Ameloblastoma↗
PubMed1990

Atypical peripheral ameloblastoma of the palate.

Clinical, radiological and histological characteristics of the peripheral ameloblastoma are briefly outlined. A case found occurring in the palate and presenting with atypical histological features is reported. The differential diagnosis of this lesion, its treatment and histogenesis are discussed.

Adult↗
PubMed1990

Combined granular cell ameloblastoma and plexiform granular cell odontogenic tumour.

Granular cell ameloblastomas are uncommon lesions accounting for about 3-5% of all histologic subtypes of ameloblastoma. The plexiform granular cell odontogenic tumour, on the other hand, is a newly described lesion characterised by a monophasic plexiform pattern of granular cells. This article reports a tumour found occurring in the left mandible of a 67-year-old Indian male which histologically showed features of both the aforementioned lesions.

Aged↗
PubMed1989

High-grade malignant mucoepidermoid tumour of tongue. A case report.

Mucoepidermoid tumours of the minor salivary glands of the tongue are rarely encountered. A case of a high-grade malignant type is reported here. Merits of subdivision of the mucoepidermoid tumour on the basis of its malignant potential are outlined, and variations of histological presentation of the present tumour at its primary and nodal sites are discussed.

Carcinoma↗
PubMed1989

An aggressive anaplastic squamous cell carcinoma of the floor of the mouth in a young patient: report of a case.

Anaplastic squamous cell carcinoma occurring in the young patient is an uncommon disease. Only a few cases have been reported in the literature in the last 30 years. This paper presents the rare case of a young male presenting with an aggressive squamous cell carcinoma of the floor of the mouth. At the time of his admission, the tumor had already spread to the cervical and supraclavicular nodes bilaterally. The patient died before completing the course of radiotherapy. The case is discussed with special emphasis on the differential diagnosis, etiology and prognosis of the lesion.

Adolescent↗
PubMed1989

Peripheral complex odontome with ghost cell epithelium. A case report.

Odontomes are malformations of dental tissues found commonly within jaw-bones and to a lesser extent in the soft tissue. A case of peripheral complex odontome exhibiting ghost cell epithelium is presented here. The significance of the ghost cells and origin of the odontome are briefly commented upon.

Child↗
PubMed1988

Orthokeratinised odontogenic keratocysts in Malaysians.

The records of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, Malaysia, were reviewed for the incidence of odontogenic keratocysts of the orthokeratinised variety, during the 20-year-period, 1967 to 1986. Nine cases were found. The clinical, histological and radiological features of these cases are reported. Many features were similar to previous reports of this entity but a peak incidence in the second decade of life, an almost even distribution in the maxilla and mandible, and a distinct predilection for the Chinese were observed. It is suggested that these features may be peculiar to Malaysians.

Adolescent↗
PubMed1988

Histological variation of the lining epithelium of the calcifying odontogenic cyst. A light microscopic study.

The lining epithelium of thirty cases of calcifying odontogenic cysts (COC) was studied light microscopically. Results show two distinct types: 1. the classical highly-differentiated lining epithelium characterised by a basal layer of columnar cells with nuclear polarisation supporting suprabasally several layers of stellate reticulum-like cells and containing variable amount of ghost cells present in all the cases and a necessary criteria for the diagnosis of COC; 2. the undifferentiated lining epithelium which is of 2-3 cells to 5-8 cells thick, non-, para- or orthokeratinised and resembled reduced enamel epithelium. This is seen in some cases in some parts of the cystic lining. Variations within the highly-differentiated epithelium include spindle-cell change, epithelial pearl formation and ghost cell dominant type. In the present series, ten cases were associated with odontome formation, three with melanin pigment and one with clear cells. The study supports the concept that COC are lesions of odontogenic origin that may arise as primary lesions from the remains of the dental epithelium or secondarily from the lining epithelium of pre-existing lesions.

Adolescent↗