Purpose: To determine the use of surgical clips as a surrogate for localization of the excision cavity and to quantify the stability of the clips' positions during the course of external beam... Show morePurpose: To determine the use of surgical clips as a surrogate for localization of the excision cavity and to quantify the stability of the clips' positions during the course of external beam radiotherapy for breast cancer patients, using cone beam computed tomography (CBCT) scans.Methods and Materials: Twenty-one breast cancer patients with surgical clips placed in the breast excision cavity were treated in a supine position with 28 daily fractions. CBCT scans were regularly acquired for a setup correction protocol. Retrospectively, the CBCT scans were registered to the planning CT scans, using gray-value registration of the excision cavity region and chamfer matching of the clips. Subsequently, residual setup errors (systematic [Sigma] and random [sigma]) of the excision cavity were estimated relative to the clips' registration. Finally, the stability of the clips' positions were quantified as the movement of each separate clip according to the center of gravity of the excision cavity.Results: When clips were used for online setup corrections, the residual errors of the excision cavity were Sigma(left-right) = 1.2, sigma(left-right) = 1.0; Sigma(cranial-caudal) = 1.3, sigma(cranial-caudal) = 1.2; and Sigma(anterior-posterior) = 0.7, sigma(anterior-posterior) = 0.9 mm. Furthermore, the average distance (over all patients) between the clips and centers of gravity of the excision cavities was 18.8 mm (on the planning CT) and was reduced to 17.4 mm (measured on the last CBCT scan).Conclusion: Clips move in the direction of the center of gravity of the excision cavity, on average, 1.4 mm. The clips are good surrogates for locating the excision cavity and providing small residual errors. (c) 2011 Elsevier Inc. Show less
This thesis consists of two parts. In part I, we have demonstrated that preoperatively administrated systemic (neoadjuvant) therapy is a feasible treatment strategy in early stage breast cancer to... Show moreThis thesis consists of two parts. In part I, we have demonstrated that preoperatively administrated systemic (neoadjuvant) therapy is a feasible treatment strategy in early stage breast cancer to achieve improved surgical options and to assess tumor response. We also demonstrated that overexpression of the breast cancer stem cell marker aldehyde dehydrogenase-1 in early stage breast cancer patients is inversely associated with age and is of prognostic importance. In part II, we have demonstrated proof-of-principle of intraoperative tumor detection and image-guided tumor resection by using the novel technique of near-infrared fluorescence imaging. We have performed two clinical trials to optimize the use of indocyanine green as a near-infrared fluorescence lymphatic tracer for the sentinel lymph node procedure in breast cancer patients. Show less
Women from families in which many individuals have developed breast and/or ovarian cancer may request for DNA-testing. A DNA-test result may disclose their own risks to develop cancer (again),... Show moreWomen from families in which many individuals have developed breast and/or ovarian cancer may request for DNA-testing. A DNA-test result may disclose their own risks to develop cancer (again), their relatives__ risks and subsequent options for medical surveillance. This thesis describes several multicenter studies in the Netherlands about the psychological and medical impact of DNA-testing on the lives of these women and their relatives. Despite their accurate understanding of the global meaning of DNA-test result, many participants interpreted the result differently from what the genetic-counselor had actually communicated. Like in a children__s whisper game, their relatives also misinterpreted the information communicated by the first messenger. The messengers__ misinterpretation was not only related to their inaccurate thoughts about heredity and cancer in general, but also to their feelings, and especially to their unfulfilled need for certainty, sense of self and unresolved existential issues. The presence of misinterpretations predicted the extent of the counselees' distress and the medical decisions after DNA-test result disclosure. The study results are described in their historical and theoretical context, followed by practical clinical suggestions for genetic-counselors and psychologists. For instance, we suggest that genetic-counselor try to avoid the communication of ambiguous DNA-test results that do not have medical consequences. Show less
Despite major advances in breast cancer diagnostics and treatment over the years, the disease is still a leading cause of death in women worldwide. Primary breast tumors can be treated relatively... Show moreDespite major advances in breast cancer diagnostics and treatment over the years, the disease is still a leading cause of death in women worldwide. Primary breast tumors can be treated relatively well with radiation, surgery, chemotherapy or a combination of these treatments. The occurrence of distant metastases derived from the primary tumor however, results in a considerable decrease in disease prognosis. Metastasis formation occurs through a series of distinct cell biological steps (outlined above). Understanding the molecular mechanisms that underlie each of these steps will help in the development of more successful anti-metastasis treatments. In this thesis, both in vitro and in vivo studies are described that aim at unraveling some of the processes involved in metastasis formation: signaling by components of the focal adhesions and cell migration. Show less
