HER-2/NEU OVEREXPRESSION AND MUTATIONS OF THE TP 53 GENE IN ADULT PATIENTS WITH HIGH GRADE OSTEOSARCOMA - OUR EXPERIENCE

Konference: 2006 31st Congress ESMO - účast ČR

Kategorie: Nádorová biologie/imunologie/genetika a buněčná terapie

Téma: Molecular markers

Číslo abstraktu: 871P

Autoři: MUDr. Dagmar Adámková Krákorová, Ph.D.; MUDr. Vladimír Spurný, CSc.; Vladimir Veselý; Petr Hušek

Introduction: Patients with primary bone cancers should be evaluted by a multidisciplinary team with demonstrated expertise in the management of such patients.
Treatment: Chemotherapy has significantly increased 5-year survival rates for patients with localised tumor from 20 % to the 60 %.
Today, an aggressive chemotherapy regimen before and after surgery is the standard treatment for high grade osteosarcoma. The chemotherapy generally include high-dose methotrexate, doxorubicin, cisplatin +- ifosfamide given in various combinations.
The histologic response of the primary tumor to preoperative chemotherapy is an important factor for survival, for the evidence of metastasis and local recurrence.
Problems: Since the introduction chemotherapy 20 years ago, the survival of patients with osteosarcoma has not improved significantly. Further alterations in chemotherapy are likely to involve escalation in intensity and additional new agents, the therapeutic risk is to high. The possibility to be able to predict, at the time of diagnosis, which patients are at increased risk of treatment failure with the current standard therapy, is very important.
Metastatic disease, large tumor volume, older age at presentation, pretreatment serum LDH, axial site of the tumor, histological subtype of OS and histological response (necrosis ratio lower then 90%) on preoperative treatment have been associated with a poor outcome.
Patients and methods: The overexpresion of HER-2/neu and p53 has been asociated with poor outcome in many neoplasms. We studied biopsy of 15 adult patients treated for high grade osteosarcoma in the Department of medical oncology and radiotherapy St. Anna¨s University Hospital in Brno (2002-2005). None of the tested samples showed gene amplification for HER-2/neu ( using IHC, due to negativity was FISH not made). Mutation of the TP 53 gene was found in ten samples (66,6%), there was no correlation among p53 over expression and histological response.
Conclusion: Neither HER2/neu nor p53 expression was important for the biology of adult high grade osteosarcoma patients in this population.

Datum přednesení příspěvku: 29. 6. 2006