Pramila R Anne | PubMed Health

PubMed2006

Impact of Her-2 Neu overexpression on outcome of elderly women treated with wide local excision and breast irradiation for early stage breast cancer: an exploratory analysis.

OBJECTIVE: The purpose of this study was to investigate the prognostic significance of Her-2 neu status in elderly patients managed with breast conservation strategy for stage I-II breast cancer. METHODS: We conducted an IRB approved retrospective review of 153 women age 70 and older with stage I-II breast cancer, managed with wide local excision and breast radiation between January 1997 and December 2002. The subset of 106 patients had a known Her-2 neu status and was analyzed for primary patient and tumor characteristics. These characteristics were correlated with cause specific survival (CSS), overall survival (OS), and combined nodal and distant failure (NDF). Her-2 neu positivity was confirmed with FISH HercepTestTM. Statistical tests included Cox regression, contingency table and Kaplan-Meier analysis. RESULTS: Median follow-up was 55 months and patient's median age was 76. Twenty two percent of patients were Her-2 neu positive and 78% were Her-2 neu negative. Her-2 neu positivity was significantly associated with high histologic grade (P = 0.008), T2 stage (P = 0.001) and positive axillary lymph nodes (P = 0.02) among 73 patients who had surgical assessment of axilla. Overall, only 15 patients (14%) received chemotherapy. There were no recurrences in the breast. Her-2 neu positivity predicted for NDF and CSS on multivariate analysis. Projected 5-year freedom from NDF was 70% for Her-2 neu positive and 97% for Her-2 neu negative patients (P < 0.01, log-rank). CSS was 86% for Her-2 neu positive and 98% for Her-2 neu negative patients (P < 0.01, log-rank). OS was no different between Her-2 neu positive and Her-2 neu negative patients (80% versus 85%, P = 0.25). CONCLUSIONS: Her-2 neu amplification predicts development of NDF and negatively influences CSS, but not local control or OS in elderly patients treated with breast conservation. Similar to the trend in younger patients, Her-2 neu positivity may be used in the future to consider more aggressive treatment strategies in elderly patients.

Age Factors↗

PubMed2004

Inverse treatment planning using volume-based objective functions.

The results of optimization of inverse treatment plans depend on a choice of the objective function. Even when the optimal solution for a given cost function can be obtained, a better solution may exist for a given clinical scenario and it could be obtained with a revised objective function. In the approach presented in this work mixed integer programming was used to introduce a new volume-based objective function, which allowed for minimization of the number of under- or overdosed voxels in selected structures. By selecting and prioritizing components of this function the user could drive the computations towards the desired solution. This optimization approach was tested using cases of patients treated for prostate and oropharyngeal cancer. Initial solutions were obtained based on minimization/maximization of the dose to critical structures and targets. Subsequently, the volume-based objective functions were used to locate solutions, which satisfied better clinical objectives particular to each of the cases. For prostate cases, these additional solutions offered further improvements in sparing of the rectum or the bladder. For oropharyngeal cases, families of solutions were obtained satisfying an intensity modulated radiation therapy protocol for this disease site, while offering significant improvement in the sparing of selected critical structures, e.g., parotid glands. An additional advantage of the present approach was in providing a convenient mechanism to test the feasibility of the dose-volume histogram constraints.

Algorithms↗