Segmental odontomaxillary dysplasia: report of a series of 5 cases with long-term follow-up.

We report a series of 5 cases of segmental odontomaxillary dysplasia (SOMD) with follow-up periods ranging from 8 to 21 years, bringing the total number of reported cases to 45. SOMD is a sporadic, mesoectodermal dysplasia that presents early in life, possibly as early as in utero and exhibits male gender predominance (1.7:1.0). Its features include enlargement of the soft tissue and/or bone of 1 hemimaxilla that may produce mild facial asymmetry. Subsequent growth of the affected area is proportional to that of the unaffected hemimaxilla. Sclerotic radiographic bone changes and dental developmental abnormalities are also present. The dense bone, which often exhibits a radiographic vertical orientation of the trabecular bone pattern, is typically associated with delayed eruption of the teeth. Congenitally missing premolar teeth (either or both) is a common feature of this condition that is of significant diagnostic value. Although ipsilateral cutaneous findings have been reported in 23%, our cases exhibited none. Computed tomographic imaging demonstrated extensive involvement of the maxillary bone, including the lateral wall and floor of the maxillary sinus and the hard palate. The affected bone presents no impediment to either orthodontic tooth movement or to the successful osteointegration of dental implants. The cause of SOMD is unknown; the clues to the cause of this unusual phenotypic expression are buried in the intricacies of developmental biology within the first branchial arch.

Multiple malignant salivary gland neoplasms: mucoepidermoid carcinoma of palate and adenoid cystic carcinoma of floor of mouth.

Salivary gland tumors usually occur as single lesions. To have more than one tumor is unusual. We report a case of an adult male who presented with a mucoepidermoid carcinoma involving the minor salivary glands of the palate at age 57 years, followed by an adenoid cystic carcinoma of the floor of mouth at age 63 years. The patient later succumbed to non-Hodgkin lymphoma at age 72 years. There are 31 acceptable cases of multiple malignant salivary gland neoplasms reported in the world literature. Multiple malignant tumors of the same histologic type are more common than those of different histologic type. Bilateral acinic cell adenocarcinoma was the most frequent combination of multiple salivary gland malignancy, accounting for 14 cases (10 synchronous and four metachronous). All involved the parotid glands bilaterally with the exception of one case that involved parotid and submandibular gland. Polymorphous low-grade adenocarcinoma accounted for three of the four cases of multiple malignant tumors involving minor salivary glands. Individuals with a history of malignancy are at risk for the development of additional malignant tumors and should receive appropriate clinical follow-up.

Oral Hodgkin lymphoma: a wolf in wolf's clothing.

Hodgkin lymphoma typically presents as a nodal lesion and infrequently involves extranodal sites. The English language literature contains only 7 reports of primary Hodgkin lymphoma arising in the oral mucosa in the absence of nodal disease. We report a case of primary, extranodal Hodgkin lymphoma in the palatal mucosa of a 79-year-old white female. An incisional biopsy revealed a diffuse, mixed cellular infiltrate, consisting of benign lymphocytes, plasma cells, histiocytes, and foci rich in eosinophils. Within this background was a scattering of large, atypical cells, including Reed-Sternberg forms that exhibited immunoreactivity for CD30 and CD20 and nonreactivity for CD15 and CD45RO, supporting a diagnosis of classical Hodgkin lymphoma. Positron emission tomography exhibited a single focal area of abnormal hypermetabolic activity involving the left palate area, without involvement of any other site. The clinical stage was Ann Arbor I-A. The primary tumor and submandibular and upper neck lymph nodes were treated with a 6-MV photon beam to a total dose of 4000 cGy. There was no evidence of disease at 15-month follow-up.

Keratoameloblastoma: a tumor sui generis or a chimera?

The term keratoameloblastoma has been used to describe a histologically heterogeneous group of ameloblastoma variants which have in common the formation of keratin by the ameloblastomatous epithelium. The English language literature contains reports of only 12 cases of keratoameloblastoma, of which 4 cases exhibited a papilliferous component. We report a unique tumor that we believe falls within the broad histopathologic spectrum of keratoameloblastoma. We review the key clinical and histopathologic features of the previously reported cases of keratoameloblastoma and present an additional case that presented as an expansile, radiolucent lesion with internal opacification between the roots of teeth in the left anterior maxillary alveolar ridge of a 45-year-old white male. There is wide variation in the histopathologic appearance of cases reported under the appellation keratoameloblastoma. Our case exhibited a histopathologic feature shared by only 2 of the previously reported cases, notably islands and anastomosing cords of epithelium forming lamellated, pacinian-like stacks of parakeratin that extruded into the collagenous tumor stroma without eliciting a foreign body response. Due to the small number of reported cases, we are unable to accurately assess whether the biologic behavior of keratoameloblastoma differs from other histologic types of ameloblastoma.