Meme kanserli olgularda HER2/neu pozitifliğinin ve trastuzumab kullaniminin beyin metastazi gelişimine etkileri

Aim : Breast cancer is the most common cancer in women. There are many prognostic and predictive factors. HER-2 onacogene is established approximately 25% of cases. It is an independent negative prognostic factor. But in recent years with the use of trastuzumab, monoclonal antibody developed against HER-2 it has been successful in the treatment of metastatic patients with both early and metastatic breast cancer. There is conflicting information regarding Trastuzumab positive results and the the prevalence of in cases of brain metastasis. The aim of our study is to compare the risk of brain metastasis in patients HER-2 positive metastatic breast cancer using trastuzumab and in patients who do not use.Materials and methods: 1248 breast cancer patients were followed up retrospectively in Dicle University Faculty of Medicine Department of Medical Oncology. Among these 295 patients were HER-2 positive (+3 by immunohistochemistry or Fish-positive). 4 patients initially excluded from the study because of earlier brain metastases. 291 patients HER-2 positive were followed up in terms of factors affecting brain metastas. 132 out of 291 patients HER-2 positive were in metastatic phase. 42 patients out of 132 metastases breast cancer were those not using trastuzumab, 90 patients, however, were the ones using trastuzumab. In patients it was assessed with parameters such as using trastuzumab or do not use, growth rates of brain metastases and influencing the ER, PR, diagnosis stage, the diagnosis of metastasis, grade, menopausal status, histological type, gender. Statistical analyses were made by using the SPSS 16.0 program. P ? 0.05 values was considered significant.Findings: All breast cancer patients (1248 patients) were found to be 8.4% of brain metastases; while rate of HER-2 negative patients was 5.8%, it was 17.2% in patients with HER-2 positive. In all patients HER-2 positive (291 patients), the rate of brain metastasis was 7.5% in 145 patients not using trastuzumab, and the rate was 26.7% of 146 patients using trastuzumab (p: 0.000). 132 out of 291 HER-2 positive breast cancer patients were metastatic. 132 HER-2 positive metastatic patients the rate of brain metastases was 37.8%. The rate was 26.1% in patients not using trastuzumab, and the rate was 43.3% in patients using trastuzumab (p: 0.059). In Multivariant analysis use of trastuzumab above two step was increasing the frequency of the of brain metastasis. (p = 0.051, OR = 1.976, 95% CI = 0.998 to 3.915). Being ER or PR positive showed a protective effect in terms of brain metastases. (P = - 0,017, OR = 0.411; 95% CI = 0.199 to 0.851). Other parameters were not significantly different between the two groups in terms of multivariant analysis.Results: We established that in HER-2 positive patients, the rate of brain metastasis with HER-2 positive trastuzumab therapy patients was high. The reasons may be the prolonged survival in patients with trastuzumab, better control of systemic disease, and insufficiency in preventing the devolopment of brain metastasis because trastuzumab does not exceed blood brain barrier. Patients receiving HER-2 positive trastuzumab due to high rate of brain metastases, in this patient group prophylactic whole brain radiation can be on the agenda. We have determined that being one of the ER or PR receptors positive decrease the frequency of brain metastases. It has been observed that other factors statistically do not affect the prognosis significantly.Key words: Trastuzumab, HER-2 positive breast cancer, brain metastasis