Mammography findings following electron intraoperative radiotherapy or external radiotherapy for breast cancer treatment.

Radiotherapy following breast cancer conserving surgery decreases the risks of local recurrence. Because 85% of breast cancers relapse in or around the surgical bed there has been some debate on the need for irradiating the whole breast. Electron intraoperative radiotherapy (ELIOT) has been used as a viable alternative for conventional external radiotherapy (RT). While the former requires a single dose of 21 Gy in the tumoral bed, the latter requires 5-6 weeks of irradiation with a total dose of 50 Gy and a boost of 10 Gy that irradiates the surgical bed. Herein, we investigated whether any significant differences exist between the mammography findings obtained from patients submitted to one of the two techniques. Two groups of 30 patients each were included in this study. All patients had mammographies taken at 12 and 24 months after finishing treatment. The mammography findings evaluated were: cutaneous thickening (>2mm), architectural distortion secondary to fibrosis, edema, calcifications (both benign and malignant), and fat necrosis. For all variables studied, there was no statistical difference between the two groups. This indicates that the mammography findings obtained in either 12- or 24-month follow-up periods after breast cancer conserving surgery are similar, regardless of which of the two radiotherapy techniques (ELIOT or RT) is employed as a treatment for breast cancer.

Intraoperative radiotherapy in the conventional linear accelerator room for early breast cancer treatment: an alternative choice in developing countries.

Intraoperative radiotherapy with a single dose of electrons (ELIOT) in the conservative treatment of breast cancer is a possibility under evaluation in clinical trials. The costs of the mobile linear accelerator with a robotic arm, used in intraoperative radiotherapy, are prohibitive for poor countries. The aim of this study was to evaluate the feasibility of ELIOT in the accelerator room of the Radiotherapy Service for early breast cancer treatment. We analyzed 40 patients submitted to breast conservative surgery and ELIOT, in the accelerator room of the Radiotherapy Service at the Hospital of Pontificia Universidade Católica do Rio Grande do Sul in Brazil from January 2004 to July 2005. Patients with unifocal breast carcinoma smaller than 25 mm, aged over 45 years, who were candidates for conservative surgery were selected and a total dose of 21Gy was delivered, without further radiotherapy. In the short-term follow-up (median 18 months), six patients (15%) presented with some grade of fibrosis under the scar. One case (2.5%) of local recurrence was reported. There are no cases of contralateral carcinoma or distant metastases so far. Our data show that intraoperative radiotherapy with electrons can be safely performed in an accelerator room with a conventional machine.

Identification of sentinel node in breast cancer.

Axillary lymphadenectomy is a very important procedure in the staging of breast cancer patients. However, it is associated with a significant morbidity rate. On the other hand, using early diagnosis we can see a high number of cases where the lymph nodes are negatives. With the intention of avoiding unnecessary axillary dissection, the possibility of evaluating a single node has been studied. This lymph node, defined as "sentinel node", would be the first to receive tumoral lymphatic drainage. The aim of this study is to evaluate: (i) the efficacy of the methods to identify the sentinel nodes, (ii) estimate the predictability of the histological examination of the sentinel node in comparison to other nodes of the axilla, (iii) compare the efficacy of the frozen section regarding the definitive histological examination of the same node. This study was performed in 29 patients, and the sentinel node was identified in all of them. It was metastatic in 7 (24.1%). Out of the 22 patients where the node was negative, 15 were submitted to complete dissection. Out of these 15, there was one case (6.7%) where one lymph node of the first level was positive. All 7 patients with the positive sentinel node were submitted to axillary dissection. When comparing the histological examination of the sentinel node with other nodes, we got a sensitivity of 87.5%, specificity of 100%, predictive positive value of 100%, predictive negative value of 93% and efficacy of 95%. The intra-operative examination was made in 24/29 cases (82.7%). The correlation between both examinations was 95.8%. This study shows that the technique of the sentinel node will be a reliable method to avoid radical axillary dissection in breast cancer patients with early diagnosis.