A whole series of advantages that have motivated the organization by MD Anderson Madrid in association with the Spanish Society of Surgical Oncology (SEOQ) of a "Workshop on Marking and Radio-guided Surgery of non-palpable lesions and / or of difficult surgical localization with 125I seed" on Saturday, February 17 at the hospital. Directed by Dr. Rioja, this workshop aims to provide theoretical and practical knowledge on the technique for medical teams involved in the treatment of breast cancer (radiologists, surgeons and nuclear medicine), so that they can put it into practice in their daily work. Currently, MD Anderson Madrid is the only private center that performs this technique in Spain.
Designed primarily to "mark for the surgeon lesions that he is not able to touch and which, therefore, would be difficult to remove", emphasizes Dr. Rioja, the first step of this technique is the implantation, through a needle, of an iodine 125 seed which consists of a titanium capsule 4 millimeters long and 0.5 millimeters in diameter at the center of the lesion. "We puncture the breast and usually control by ultrasound where we want to take the needle", explains the specialist, who points out that, "once the lesion is located, we only have to release the seed at that point". A technically very simple mechanism that can also be performed up to several days before surgery.
During the intervention, the surgeon first locates the seed visually through X-ray techniques and then, detects the radioactive activity of the iodine by using a manual gamma detection probe, which allows him to proceed to the removal of the lesion with great precision. Together with the lesion, the surgeon removes the iodine seed, which, as the doctor points out, "has the minimum amount of radioactivity essential to carry out the technique successfully". As he assures, "they are negligible, very low irradiation quantities".
Another advantage of this technique of marking with iodine 125, compared to the traditional technique using a harpoon, is its greater precision at the time of extirpating the lesion. "This technique allows us to focus on the lesion very well, which significantly reduces the number of patients who have to undergo surgery again because the entire tumor has not been removed," says Dr. Rioja.
Other uses of the iodine 125 seed marking technique
Although it is used mainly in malignant lesions of the breast, it is possible to use this iodine-125 marking technique in benign breast lesions such as, for example, micro-calcifications, and even in lesions that are not so small, but which are not palpable. Thus, for example, Dr. Rioja explains that, "in a 5 cm micro-calcification of the breast, we could delimit the most cranial part, the most caudal and the medial part to limit the area and facilitate the removal by the surgeon".
Likewise, lately this technique is also being used in non-palpable lesions located in other areas such as the abdomen, muscles or lung, with very good results. The difference in these cases is that the marking technique is usually not controlled with ultrasound, but with other imaging techniques such as, for example, computerized axial tomography (CAT).