LOCATION RADIOGUISED BREAST LESIONS, WITH IODINE-125 SEED IMPLANT

Mendes S. (Beneficência Portuguesa de São Paulo), Rodrigues C. (Beneficência Portuguesa de São Paulo), Gabure L. (Beneficência Portuguesa de São Paulo), Rostelato M. E. C. M. (Beneficência Portuguesa de São Paulo), Zeituni C. A. (Beneficência Portuguesa d

Beneficência Portuguesa de São PauloObjective: To reduce radiological procedures to locate a non-palpable breast lesion, in order to elucidate the diagnosis of breast lesions, a biopsy is necessary to confirm malignancy, only in this way are programmed the excision of the compromised breast sector. Currently, two methods for surgical orientation are indicated: ultrasonography (USG) and / or mammography (esterotaxy), on the same day of the surgical procedure. For such, markers are used so that the removal of the lesion with conservative techniques is done with greater precision, without affecting a large amount of tissue. When the lesion is visible to the ultrasound, the preference is for this propaedeutic method, which besides Well tolerated by the patient has the marking of the lesion facilitated, because it is in real time. The lesions visualized, only, by mammography, are marked by stereotaxy, whose basic principle is to allow its location in three dimensional axes, in the face of difficulties and inconveniences (ROLL), as a technique of choice for non-palpable lesions. According to this method, the lesions are marked precisely by ultrasound or stereotaxy using Sero-albumin, labeled with 99-99Tc technetium (low energy gamma ray emitting radioactive isotope). We propose the marking of non-palvable lesions by implantation of the I-125 seed is a safe method because the seeds are encapsulated in titanium, an inert element that does not cause rejection (biocompatible material) when in direct contact with the human tissue 5. Its Application in the mammary parenchyma is performed through ultrasound-guided biopsy or mammography in the same way as the radiopharmaceutical injection in the conventional ROLL method10. The seed will not generate risk of dispersion of the radioactive material, a reality usually faced after the injection of the radiopharmaceutical. The implantation of the I-125 seed is a low cost method, in the Brazilian market the cost equals the cost of the radiopharmaceutical used in a conventional ROLL procedure. In addition, the process of seed production in the national territory is being tested, which will make the alternative of using seeds a more economical method in the market. Associated with this is the reduction in the number of additional procedures such as scintigraphy, mammography, and ultrasound, necessary for the success of conventional techniques 3, generating greater savings for the health sector. In view of the above, this study seeks to validate the efficiency of the non-palpable guided radiographic method of localization of breast lesions with the use of iodine seeds125. Methodology: The “seed” consists of a small titanium capsule of 0.8mm external diameter, 0.05mm wall thickness and 4.5mm length. Inside it there is a silver wire of 0.5mm in diameter and 3mm in length, material to which Iodine-125 is absorbed. [5] Iodine-125 is a gamma emitter with a mean energy of 29 keV, has Half-life of 59.4 days [6,7]. The activities used for this isotope will be approximately 7.4 to 37 MBq (0.2 mCi to 1.0 mCi). The radioactive seed will be introduced into the lesions of non-palpable breast by ultrasound or mammography by stereotaxia. A 18 gauge needle is used to introduce the seed. Once guided to the desired site of the breast lesion the seed will be implanted into the mammary parenchyma or tumor tissue. A mammogram or ultrasonography image soon after the implant will be performed to confirm proper placement of the seed. The seed will be removed the day the patient performs the surgical procedure of resection of the area of the lesion to which it has been implanted. For the intraoperative detection of the I-125 seeds the gamma-probe, model Europrobe® (EURORAD) will be used. The gamma-probe detection probe will be handled by the surgeon to locate the capture area for the seed for initiation of resection. After determination of the site, the area is removed with margin referenced by the seed, as a central point using the radiological image to determine the sectioned area and referred for pathological analysis, the gamma-probe will be used to confirm the presence of the seed in the resected specimen And the absence of I-125 uptake into the breast after resection will also serve as the basis for both the seed and the lesion being removed. Results: The 30 patients submitted to the method all had and localized lesion, making the study possible for the pathologist and there was no migration of the seeds.Conclusion: Method of easy application, low cost, reduction of exams performed, greater speed in surgical preparationbreast cancer, radioactive seed, non-palpable breast lesion

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