Abelardo Meneses‐García

Odontogenic tumors in Mexico: a collaborative retrospective study of 349 cases.

Reports about the frequency of odontogenic tumors are scarce, and diagnostic criteria used in the reports are not uniform. This article presents the results of a retrospective study of odontogenic tumors recorded in four services of diagnostic pathology in Mexico City (two dental schools, one cancer hospital, and one private oral pathology service). The final diagnosis in each case was based on the 1992 histologic criteria of the World Health Organization. The frequency of odontogenic tumors, expressed as a percent of all oral and maxillofacial specimens, ranged from 0.8% in the cancer hospital (0.02% of all biopsies) to 3.7% in the private oral pathology service. The frequency was identical for the two dental schools (2.5%). We found a total of 349 odontogenic tumors; of these, 345 were benign (98.8%), and 4 (1.1%) were malignant (3 were primary intraosseous carcinomas and 1 was a malignant ameloblastoma). The most frequently occurring tumors were odontoma (34.6%), ameloblastoma (23.7%), myxoma (17.7%), adenomatoid odontogenic tumor (7.1%), and calcifying odontogenic cyst (6.8%). Although relatively rare, odontogenic tumors are still an important cause of extensive surgical procedures in Mexico.

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

BACKGROUNDnCalcifying 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).nnnMETHODSnThe 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.nnnRESULTSnCCOT 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.nnnCONCLUSIONSnOur results suggest that ghost cell odontogenic tumours comprise a heterogeneous group of neoplasms which need further studies to define more precisely their biological behaviour.

p53, p21, Rb, and MDM2 proteins in tongue carcinoma from patients 75 years

Relatively rare squamous cell carcinomas of the tongue in young patients may be associated with different etiologic factors and pathogenetic mechanisms than carcinomas from the same site in older patients. Alterations in cell cycle proteins likely contribute to the biologic behavior of these neoplasms. The purpose of this investigation was to evaluate cell cycle proteins (p53, p21, Rb, MDM2) in lateral tongue cancers from patients at the two ends of the age spectrum. All available archived lateral tongue carcinomas from patients < 35 years (n = 36, 23 males and 13 females) were sectioned, immunohistochemically stained, and evaluated. Protein expression was scored as percent positive nuclei. An equal number of sequentially accessioned lateral tongue specimens from patients > 75 years (23 males and 13 females) were stained and compared. Positive p53 staining was seen in 18/36 of the < 35-year group versus 24/36 of the > 75-year group (p = 0.149). Increased p21 staining (both percent of positive cells and intensity) was evident in 25/32 of the < 35-year group versus 24/32 of the > 75-year group (p = 1.0). Increased p21 expression was seen in both p53-positive and -negative cases in both age groups. Rb protein was increased in 16/29 of the < 35-year group versus 17/26 of the > 75-year group (p = 0.58). Fourteen cases (4/35 vs 10/36, p = 0.135) showed positive MDM2 staining; MDM2-positive cases were also p53 positive in 4/4 younger and 8/10 older patients. We conclude that p53, p21, Rb, and MDM2 are over-expressed in lateral tongue cancers, and that immunohistochemical profiles are heterogeneous. A p53-independent pathway of p21 induction is supported by the results; p53 suppression may be associated with MDM2 protein expression in a subset of cancers. Significant differences in the expression of p53, p21, Rb, and MDM2 proteins are not evident in lateral tongue carcinomas from patients < 35 years as compared to patients > 75 years.

Interventions for central giant cell granuloma (CGCG) of the jaws.

BACKGROUNDnCentral giant cell granuloma (CGCG) of the jaws is a rare benign tumour with an unknown aetiology accounting for up to 7% of tumours in the mandible (lower jaw) and the maxilla (upper jaw).nnnOBJECTIVESnThis systematic review focused on assessing the effects of primary non-surgical versus primary surgical interventions or any other treatment or placebo for treating central giant cell granuloma of the jaws.nnnSEARCH STRATEGYnRelevant randomised controlled trials (RCTs) were identified from the Cochrane Oral Health Groups Trials Register (July 2009); CENTRAL (The Cochrane Library 2009, Issue 3); MEDLINE (1950 to July 2009); EMBASE (1980 to July 2009); and LILACS (1982 to July 2009). We scanned bibliographies of relevant studies for possible references to additional trials as well as prospective clinical trial registries. Eligible RCTs were included regardless of the language of publication.nnnSELECTION CRITERIAnRandomised controlled trials involving a comparison of primary non-surgical interventions with primary surgical interventions or any other treatment.nnnDATA COLLECTION AND ANALYSISnTwo review authors independently assessed eligibility, risk of bias and extracted data. The Cochrane Collaboration statistical guidelines were followed.nnnMAIN RESULTSnWe did not find any study evaluating the effects of primary surgical versus primary non-surgical interventions for central giant cell granuloma of the jaws. However, we included and analysed one RCT with unclear risk of bias, evaluating the effects of calcitonin versus placebo for central giant cell granuloma of the jaws. No significant difference was found in the proportion of patients with increased volume of more than 10% of the lesion compared to the pretreatment measurement at 3 months of follow-up (one RCT, 14 participants; risk ratio (RR) 3.00, 95% confidence interval (CI) 0.40 to 22.30).nnnAUTHORS CONCLUSIONSnWe did not find RCTs evaluating the effects of primary surgical versus primary non-surgical interventions for central giant cell granuloma of the jaws. Although a number of non-surgical therapies have been proposed for treating central giant cell granuloma of the jaws, our review did not identify evidence from RCTs to support their use. More research is needed on this topic.

A pharmacoeconomic analysis of the collection and preservation of samples in the biobank of the “Instituto Nacional de Cancerología” in Mexico City

In this work we estimated the budgetary impact of the samples produced by the biobank of the “Instituto Nacional de Cancerología” (BT-INCan) to set a recuperation fee from the perspective of the Health Ministry of Mexico. The study is an observational retrospective review of the direct medical costs (DMCs) of the processes involved in cryopreservation of thexa0samples collected, on a per sample basis, including materials, laboratory tests, personnel, and administrative costs. Materials and labor costs were determined by information collected from the BT-INCan. DMCs were providedxa0depending on the type of sample: plasma, tissue and biopsy; they were calculated according to the process required to preserve them. Sensitivity analysis was performed using bootstrap. Recuperation costs ranged from 130 to 155 USD. Costs were considered on a 5-year time frame for the maintenance per sample, which is the average time that a sample is kept in the BT-INCan. The cost analysis is perceived as an approximation to the most adequate recuperation fee per sample needed to guarantee the correct development of the BT-INCan. This work provides a basis and valuable information about costs, to enable several health institutions to strategically plan and manage a biobank or even motivate to establish their own biobank.

Pathology of Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is a rare and aggressive subtype of locally advanced breast cancer (LABC). Its diagnosis is primarily clinical; however, a pathological confirmation of invasive cancer is required.