Prognostic factors and expression of MDM2 in patients with primary extremity liposarcoma

Can HMGI-C be used as an aid with MDM2 and CDK4 to differentiate liposarcoma subtypes from their mimics?

PURPOSE

Liposarcoma represents the most common soft tissue tumors in adults. The tumors are characterized by a high morphological diversity and a great variation in biological behavior. Atypical lipomatous tumors represent a distinctive subset of mesenchymal neoplasms featuring mature adipocytic differentiation. Histologically, atypical lipomatous tumor might be easily confused with lipoma. Conversely, dedifferentiated liposarcoma may be confused with other spindle cell/pleomorphic undifferentiated tumors.

METHODS

A group of liposarcomas was analyzed by investigating the MDM2, CDK4, and HMGI-C proteins. The study was extended to a group of lipomas and non-lipomatous sarcomas, to determine whether the immunohistochemical investigation of these proteins might play any diagnostic role.

RESULTS

Our data suggest that ordinary lipomas may form a molecular genetic and morphological continuum with atypical lipomatous tumor. At one end of the spectrum are lipomas characterized by HMGI-C activation and at the other end are atypical lipomatous tumors with overrepresentation of the HMGI-C, CDK4, or MDM2 proteins. These findings not only provide insights into the molecular pathogenesis of lipomatous tumors, but also indicate that the immunohistochemical analysis of HMGI-C, CDK4, or MDM2 may help to increase diagnostic accuracy.

CONCLUSIONS

HMGI-C is a useful adjunct in the diagnosis of atypical lipomatous tumor and dedifferentiated liposarcoma and differentiates them from their mimics. Therefore, in our experience, HMGI-C expression alone is of rather limited value in the differential diagnosis of liposarcoma subtypes.

Revisão de artigos de ortopedia e medicina esportiva publicados em periódicos brasileiros

O objetivo desta revisão é apresentar os artigos com especial interesse nas áreas de Ortopedia e Medicina Esportiva publicados em periódicos nacionais qualificados pelo ISI, fora da área de publicação específica em Ortopedia em dois anos. Neste período foram localizados 38 artigos publicados em diversas revistas nacionais com distintos desenhos de pesquisa. Torna-se evidente uma maior divulgação das publicações em Ortopedia e Medicina Esportiva em periódicos gerais, viabilizando ao especialista maior fonte de referências e pesquisas.

Prognostic factors in the survival of patients diagnosed with primary non-metastatic osteosarcoma with a poor response to neoadjuvant chemotherapy

INTRODUCTION

Identification of variables that determine the prognosis for osteosarcoma may enable stratification of patients into subgroups with better or worse risk of local recurrence, metastases and death due to the disease. Discovery of such prognostic factors would permit selection of a subgroup of at-risk patients, with the aim of improving the therapeutic effectiveness.

OBJECTIVE

To identify prognostic factors related to local recurrence-free survival, metastasis-free survival and overall survival among patients with highly malignant primary osteosarcoma that was non-metastatic on diagnosis and had poor response to neoadjuvant chemotherapy.

SAMPLE AND METHODS

Out of 45 patients admitted to a referral center in Brazil between 2000 and 2004, 24 were selected for this study.

RESULTS

The adverse factors that influenced the risk of local recurrence and the overall survival in univariate analysis were histological subtype other than osteoblastic (p = 0.017) and tumor size greater than 15 cm (p = 0.048). In relation to metastasis-free survival, the non-osteoblastic subtype had a worse prognosis (p = 0.007). The association of histological subtype maintained its significance in multivariate analysis for all studied survival categories.

CONCLUSIONS

Tumor size greater than 15 cm is an adverse factor for local recurrence-free survival and overall survival but did not influence metastasis-free survival. The osteosarcoma histological type is a significant independent predictor for local recurrence-free survival, metastasis-free survival and overall survival.