1. Radiofrequency Ablation in Breast Cancer Evangelos Tzoracoleftherakis, MD, PhD 1, Elias Sdralis, Cptn MD 1, John Maroulis, MD, PhD 1, Panagiota Ravazoula, MD, PhD 2 1 Department of Surgery University Hospital of Rio Patras, Greece 2 Department of Pathology University Hospital of Rio Patras, Greece Objective BackgroundMaterials & Methods Conclusion References Radiofrequency ablation (RFA) of breast tumors is characterized by variable efficiency. Cell viability is principally evaluated by NADH-diaphorase and Hematoxylin-Eosin (H&E) staining techniques. Twenty patients with breast cancer, 20.7 ± 9.14mm in diameter, underwent RFA of the tumor and of the margin of surrounding breast tissue. RFA was based on the radiofrequency impedance-switching algorithm. The algorithm was based on an internally cooled probe, which carried out algorithm-guided deposition of heat in a pulse-cycle fashion and under continuous monitoring of the desiccation status of the ablated site to avoid tissue charring (until its impedance level reached 30Ω above the baseline level or a maximum time interval (tmax) was reached). A minimum time interval of 5 seconds was set as the duration of time that the electrode must be off. If the cycles of power application occurred too rapidly, the power was diverted to the 150Ω resistance load for the remainder of the 5-second interval. Surgical resection was the next step. Ki 67 evaluation is a targeting indicator of viability of malignant cells after lesion RFA of breast tumors. RFA is able to provide satisfactory local control in breast cancer. Ki 67 evaluation as a targeting indicator of viability of malignant cells after lesion RFA of breast tumors. RFA ability of providing satisfactory local control in breast cancer.. Results Sixteen patients underwent quardzantectomy (five with axillary lymph node dissection) and four unilateral total mastectomy. In fifteen patients SLNB was searched and identified (ten negative, four positive and one failure). The ablated tumor tissue was histologically examined and Ki 67 immunohistological staining was applied to evaluate cellular proliferation, invasion and survival. The mean time of operation was 119.47 ± 23.35 minutes.The mean time of RFA was 12 – 15 minutes. One patient had a post-operative complication (trauma infection). All twenty patients had a positive Ki 67 immunohistochemical staining mean value of 28.79 ± 21.42, before RFA. Ki 67 expression % The post-RFA Ki 67 expression was zero in sixteen patients. In three patients no residual tumor cells were found and in one patient the Ki 67 expression was under five percent. Recurrence developed in zero patients, to date (follow up time: 22.5 ± 2.3 months). RFA after SLNB procedure Histological examination in the different specimens showed ductal carcinoma with coagulation necrosis (fig.1) or acellular degenerated connective tissue (fig.2), severe damage to the vessels (fig.3) and degenerative cancer cells (fig.4) (H&E) Fig.1Fig.2 Fig.3Fig.4 Tissue necrosis after RFA 1..Wang, Rui, Luo, Danfeng, Ma, Xiangyi, Yang, Wanhua, Chen, Rui, Liu, Yan, Meng, Li, Zhou, Jianfeng, Xu, Gang, Lu, Yun-ping, Wang, Shixuan and Ma, Ding(2008)'Antisense Ki-67 cDNA Transfection Reverses the Tumorigenicity and Induces Apoptosis in Human Breast Cancer Cells',Cancer Investigation,26:8,830 — 835 2.Liyong Wu, Robert J McGough, Omar Ali Arabe, and Thaddeus V Samulski, An RF phased array applicator designed for hyperthermia breast cancer treatments, Phys Med Biol. 2006 January 7; 51(1): 1–20. 3.MASAKUNI NOGUCHI, MITSUHARU EARASHI, HISATAKE FUJII, KOICHI YOKOYAMA, KEN-ICHI HARADA, KOICHI TSUNEYAMA, Radiofrequency Ablation of Small Breast Cancer Followed by Surgical Resection, Journal of Surgical Oncology 2006;93:120–128 4.Vilhelm Ekstrand, Hans Wiksell1, Inkeri Schultz, Bengt Sandstedt, Samuel Rotstein, Anders Eriksson Influence of electrical and thermal properties on RF ablation of breast cancer: is the tumour preferentially heated?, BioMedical Engineering OnLine 2005, 4:41 5.Stijn van Esser Ζ Maurice A. A. J. van den Bosch Ζ Paul J. van Diest Willem Th. M. Mali Ζ Inne H. M. Borel Rinkes Ζ Richard van Hillegersbe Minimally Invasive Ablative Therapies for Invasive Breast Carcinomas: An Overview of Current Literature World J Surg (2007) 31:2284–2292 6.Shoji Oura, Takeshi Tamaki, Issei Hirai, Tatsuya Yoshimasu, Fuminori Ohta, Rie Nakamura, and Yoshitaka Okamura Radiofrequency Ablation Therapy in Patients with Breast Cancers Two Centimeters or Less in Size Breast Cancer Vol. 14 No. 1 January 2007 7.Seigo Nakamura, Mitsutomi Ishiyama, and Hiroko Tsunoda-Shimizu 1Department of Breast Surgical Oncology, Department of Radiology, St. Luke’s International Hospital, Japan Breast Cancer Vol. 14 No. 2 April 2007 8.Vilhelm Ekstrand*1,2, Hans Wiksell1,2, Inkeri Schultz3, Bengt Sandstedt4 Samuel Rotstein5 and Anders Eriksson6 1Department of Surgical Sciences, Karolinska Institutet, Stockholm, Sweden, 2VibraTech AB, Stockholm, Sweden, 3Department of Surgery, Karolinska Institutet at Danderyd's Hospital, Stockholm, Sweden, 4Department of Pathology, Karolinska Institutet at Danderyd's Hospital, Stockholm, Sweden, 5Department of Oncology, Karolinska University Hospital, Stockholm, Sweden and 6Department of Mechanics, Royal Institute of Technology, Stockholm, Sweden BioMedical Engineering OnLine 2005, 4:41