Mario Altini

Prediction of aggressive behavior in basal cell carcinoma

In this study, a series of aggressively behaving basal cell carcinomas has been contrasted with a series of the nonaggressive type (metastasizing lesions were not considered in this study). Aggressive tumors were characteristically more likely to be ulcerative and infiltrative. They were composed of small groups of cells often displaying an irregular spiky appearance; infiltration of cells in cords, only one or two cells thick, could be seen. There was loss of peripheral palisading; the cells tended not to show differentiation. Hyalinization of the stroma was more common in the aggressive tumors. It is postulated that by utilizing these criteria, the pathologist can confidently diagnose the majority of cases and forewarn the clinician that a particular tumor is potentially aggressive. Adequate treatment and careful follow‐up then become feasible.

Dentigerous cysts of inflammatory origin: A clinicopathologic study

The exact histogenesis of dentigerous cysts remains unknown, but most authors favor a developmental origin from the tooth follicle. The aim of this article is to report a series of 15 dentigerous cysts that we believe to be of inflammatory origin. These inflammatory dentigerous cysts occurred in the first and early part of the second decades of life. Males were affected more frequently, and there did not appear to be any racial predilection. All of the cases involved permanent teeth: premolars in nine cases, canines in four cases, and second molars in two cases. The mandible was affected twice as frequently as the maxilla. In 13 cases, nonvital grossly carious or heavily restored deciduous teeth were associated with the cysts. Some of these teeth had been extracted before the cysts were diagnosed. In the remaining two cases, both of which involved the second permanent molars, there were no nonvital deciduous teeth, however both had concomitant proliferative periostitis. All of the cysts were moderately or intensely inflamed and were lined predominantly or entirely by nonkeratinized stratified squamous epithelium that in some cases was markedly hyperplastic and exhibited anastomosing rete ridges mimicking radicular cysts. In the majority of cases, parts of the cysts were lined with a 2 to 3 cell layer thick cuboidal epithelium that we believe was derived from reduced enamel epithelium. Rests of odontogenic epithelium frequently were evident in the cyst walls. We suggest that these cysts arose as a result of periapical inflammation from any source but usually from a nonvital deciduous tooth and spreading to involve the follicles of the unerupted permanent successors. The inflammatory exudate causes separation of the reduced enamel epithelium from the enamel with resultant cyst formation. This study proposes the existence of two types of dentigerous cysts: one developmental and the other inflammatory in nature.

The calcifying odontogenic cyst. Eight new cases and a review of the literature.

Eight new cases of the calcifying odontogenic cyst have been reported. In addition, a review of the literature produced an additional sixty-five cases. This lesion can occur in any age group, but it shows a peak incidence in the second decade. It is evenly distributed between the maxilla and the manidible and occurs with equal frequency in males and females. There does not appear to be any race predilection. The calcifying odontogenic cyst may occur in association with other pathologic entities. It is postulated that it does not in every case represent a separate pathologic entity but that it may represent a secondary phenomenon which occurs within preexisting lesions.

International collaborative study on ghost cell odontogenic tumours: calcifying cystic odontogenic tumour, dentinogenic ghost cell tumour and ghost cell odontogenic carcinoma.

BACKGROUND Calcifying odontogenic cyst was described first by Gorlin et al. in 1962; since then several hundreds of cases had been reported. In 1981, Praetorius et al. proposed a widely used classification. Afterwards, several authors proposed different classifications and discussed its neoplastic potential. The 2005 WHO Classification of Odontogenic Tumours re-named this entity as calcifying cystic odontogenic tumour (CCOT) and defined the clinico-pathological features of the ghost cell odontogenic tumours, the CCOT, the dentinogenic ghost cell tumour (DGCT) and the ghost cell odontogenic carcinoma (GCOC). METHODS The aim of this paper was to review the clinical-pathological features of 122 CCOT, DGCT and GCOC cases retrieved from the files of the oral pathology laboratories from 14 institutions in Mexico, South Africa, Denmark, the USA, Brazil, Guatemala and Peru. It attempts to clarify and to group the clinico-pathological features of the analysed cases and to propose an objective, comprehensive and useful classification under the 2005 WHO classification guidelines. RESULTS CCOT cases were divided into four sub-types: (i) simple cystic; (ii) odontoma associated; (iii) ameloblastomatous proliferating; and (iv) CCOT associated with benign odontogenic tumours other than odontomas. DGCT was separated into a central aggressive DGCT and a peripheral non-aggressive counterpart. For GCOC, three variants were identified. The first reported cases of a recurrent peripheral CCOT and a multiple synchronous, CCOT are included. CONCLUSIONS Our results suggest that ghost cell odontogenic tumours comprise a heterogeneous group of neoplasms which need further studies to define more precisely their biological behaviour.

Inflammation in the context of oral cancer

The link between cancer and inflammation is specific transcription factors that once activated have the capacity to enhance expression of genes that are common to both the regulation and the production of mediators of inflammation, and also to the regulation of the survival and proliferation of cancer cells. Cellular pathways activated by chronic inflammation brought about by chronic infections, by immune-mediated diseases, or by dysregulated wound healing at sites of repetitive tissue injury, constitute risk factors for initial cell transformation and for cancer progression. In established cancers, the cancer cells induce development of an exaggerated inflammatory state in the stroma, which in turn promotes cancer growth, invasion and metastasis. Inflammatory cells of myeloid origin in the tumour-associated stroma, mediate suppression of immune responses against cancer cells, which suppression favours tumour growth. Oral submucous fibrosis, and to a lesser extent oral lichen planus are precancerous conditions in which immuno-inflammatory processes are implicated in their pathogenesis, and in their cancerous transformation, if it occurs. Although there is some evidence for an association between oral squamous cell carcinoma on the one hand and dento-gingival bacterial plaques and chronic periodontitis on the other hand, the role of inflammation as the sole cause of cancerous transformation in such cases is not proven. The purpose of this article is to elaborate on some of the more important relationships between oral cancer and inflammation, and to comment on the role of inflammation in the pathogenesis of oral squamous cell carcinoma.

Oral angiolymphoid hyperplasia with eosinophilia

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an unusual and controversial lesion that occurs primarily in the head and neck area; oral involvement is rare. A case involving the labial mucosa, in which immunoglobulin deposits were found in association with a damaged centrally located artery, is described. The clinical and pathologic concepts presented in the literature are discussed. Suggestions that these lesions should be reclassified as epithelioid or histiocytoid hemangiomas may not apply to all of the cases that are acceptable as ALHE by current criteria. Different entities, which include vascular neoplasms, Kimuras disease, and possibly other reactive conditions, may be encompassed in the Western literature as ALHE. Involvement of a small artery and occasionally a vein, often with evidence of vascular damage, was reported in 24% of the cases of ALHE that were reviewed. Single nonrecurrent lesions were seldom found in association with blood eosinophilia, although in the absence of eosinophilia, single and multiple or current lesions occurred in 60% and 40% of the cases, respectively.

CK7+/CK20- immunoexpression profile is typical of salivary gland neoplasia.

Aims:  To evaluate cytokeratin (CK) 7/20 expression patterns in salivary gland neoplasia.

Use of calretinin in the differential diagnosis of unicystic ameloblastomas.

Aims: Calretinin, a 29‐kDa calcium‐binding protein is expressed widely in normal human tissues and tumours including both unicystic and solid and multicystic ameloblastomas. The histological distinction between unicystic ameloblastomas and certain non‐neoplastic odontogenic cysts can be problematic. The objective of this study was to determine whether calretinin was expressed in the lining epithelium of odontogenic keratocysts, residual and dentigerous cysts and to determine whether this calcium‐binding protein could be used to distinguish these cysts from the unicystic ameloblastoma.

Oral Kaposi's sarcoma: a clinicopathologic study from South Africa

OBJECTIVES In this retrospective study, we defined the clinicopathologic characteristics of oral Kaposis sarcoma (KS) and determined the presence of human herpesvirus 8 in the oral lesions in a group of South African patients. These results were compared with similar data from patients in developed countries. STUDY DESIGN Eighty-one cases of oral KS were retrieved from the departmental archives. Fourteen patients with oral pyogenic granuloma served as control subjects. DNA was extracted by using a modified phenol chloroform extraction method and amplified by using polymerase chain reaction. If beta-globin DNA sequences could not be demonstrated, the patient was excluded from the study. RESULTS Of the 81 patients included in the study, 68 (84%) had been diagnosed since 1997. Oral KS was often the first presenting sign of human immunodeficiency virus infection. Some of the lesions exceeded 4 cm in diameter. The most commonly affected site was the palate (37 patients), followed by the tongue and gingiva. Multiple oral sites were frequently involved. The mean age of the patients was 34.7 years (range, 2-58 years). The male-to-female ratio was 1.31 to 1. Most of the patients (94%) were black. Human herpesvirus 8 DNA sequences were detected in 44 of the 45 cases of oral KS in which the DNA was analyzed, and in 1 case of pyogenic granuloma. CONCLUSIONS The only significant clinicopathologic differences in findings between our study and previous studies in developed countries were (1) the male-to-female ratio, (2) the preponderance of black patients, and (3) the more frequent involvement of the tongue. There are no studies reporting the clinicopathologic characteristics of oral KS in populations of developing countries.

Rhabdomyosarcoma of the oral and paraoral region

Oral rhabdomyosarcoma (RMS) was studied by analysis of eight such cases which presented over a 25‐year period. Rhabdomyosarcoma was the fourth most common oral sarcoma (7.5%) from this period after osteosarcoma (32%), fibrosarcoma (19%), and chondrosarcoma (9%). In patients younger than 20 years, RMS was the second most common sarcoma (six cases) after osteosarcoma (ten cases). Combined analysis with 113 further cases documented in the literature showed the majority of cases (71.2%) were embryonal. The alveolar subtype was considered a distant second in frequency (12.3%) even though the pleomorphic subtype was apparently more common (16.4%). However, the pleomorphic cases were diagnosed before histologic criteria were established to discern this entity from other pleomorphic sarcomas and this data is probably unreliable. Site predilections were found for the soft palate, maxillary sinus and alveolus, posterior mandibular region, cheek and lip and possibly tongue. The gingiva and floor of mouth were uncommon sites. There was a predilection for occurrence in the first two decades with a decline in the third decade. Documentation of recent cases treated with a multidisciplinary approach indicated that lesions in the oral soft tissues have a good prognosis; 17 of 21 such cases showed no evidence of disease after a mean follow‐up period of 7.2 years (SD = 4.4). In contrast, four of five cases in the posterior mandible resulted in death after a mean period of 1.1 years (SD = 0.3).