The new technique of stereotactic radiotherapy can radiate lesions more precisely without damaging adjacent healthy tissue
Lung cancer is the most common in the world. According to the Spanish Association Against Cancer (AECC), 20,000 people are diagnosed with this cancer each year in our country. Of these, it is estimated that about 20% are inoperable due to conditions of the patient, and 40% will develop distant metastases, ie, the disease will spread beyond the primary tumor and affect other organs.
A new alternative to chemotherapy treatment
So far, the standard treatment for these patient groups, which are considered inoperable, was chemotherapy with a median survival was achieved seven months. However, science has allowed to go a step further treatment. Body stereotactic radiosurgery SBRT is a new technique, and avoid the side effects of chemotherapy, has led to increased survival of these patients hastamás twenty months. "The new radiosurgery has revolutionized the treatment of lung cancer," he says Benjamin Guix, Director of the IMOR Foundation in Barcelona.
Stereotactic radiotherapy body (SRBT) addresses each tumor lesions or metastatic a radiation dose by a very small amount in each of the multiple gateways. In addition, unlike conventional radiotherapy, the SRBT manages many more beams from many more directions and much more accurately.
The new technique has a system that is able to detect and track respiratory motion. To do this, we study how the patient breathes and parameters are set with the maximum movement of inspiration and expiration minimum. "For the patient that moved or breathed deeply and exceeds the limits, the machine would stop," said the oncologist Guix. In this sense, explains this specialist, the new treatment technique allows much more accurately and patient safety, because it may increase the dose of radiation without damaging adjacent healthy tissue and reduce side effects.
In fact, the disparity in the dosage of radiation is one of the key differences between conventional radiotherapy and SRBT. While the former consists of a local control rate of 50%, the new technique has a 98%. "With conventional radiotherapy they could not be given high doses because the adjacent healthy tissue is damaged. With SBRT, however, margins may decrease a lot because you radiate only the tumor, because the margin is a few millimeters, "explains the director of IMOR, adding:" The tumor responds better to a few fractions very dose to many sessions with low doses. "
Higher survival rate for lung cancer
Stereotactic radiotherapy has been a breakthrough in the treatment of primary lung tumors in patients who, for their general condition, could not withstand surgery. In these cases, SBRT equal or superior to surgery, which until now was considered the treatment of choice results are achieved without running the risks inherent in any operation. The five-year survival is above 80%. It can be applied in lung tumors only four or five centimeters in diameter.
In the case of metastases, although stereotactic radiotherapy has been a major advance for patients with metastases, all can not have it. To prevent damage to healthy cells and cause side effects, two limits are established, one in the size of the lesion and another in the number of organs affected by the tumor. In this sense, it is established that the lesion should not exceed six feet in diameter, or the patient may have more than six lesions.
Treatment and possible side effects
The treatment takes place in a few sessions, usually between three and five. Side effects are usually very few, but there may be some, and are determined largely by the location of lesions. "When the liver is affected, a transient clinical hepatitis may occur, or, if the tumor is near the esophagus, the patient may have swallowing discomfort for several days, for example," said Guix.
The SRBT has increased the survival of seven to morethan his twenty months as people with metastases. The American Society of Clinical Oncology (ASCO) has been defined as the most spectacular SBRT in the treatment of lung cancer in the last fifteen years forward.
The Institut IMOR has all the necessary technology to perform safely SBRT for best results. SBRT has the virtue of treating one disease outbreaks omúltiples simultaneously with minimal side effects or patient discomfort