Disease-free survival
In 1985, in the United States, the first study was published on the safe primary surgery for breast cancer. Later, the results presented in it were confirmed by other surgeons. This work supported the thesis of maximum breast preservation during breast surgery. In the randomized group, more than 1,800 patients were observed, some of whom underwent simple mastectomy, and the rest local tumor resection followed by radiation therapy or without it. In a common process, patients removed axillary lymph nodes and prescribed a course of adjuvant chemotherapy.
In the group of patients who underwent local tumor resection followed by radiation therapy, the 5-year relapse-free survival was higher. In the same group, a slightly higher overall survival rate was observed. In a group of patients with a common tumor process, who underwent local resection with subsequent removal of the axillary lymph nodes, radiation therapy and adjuvant chemotherapy, in 98% of cases no relapses were observed. In the non-radiotherapy group, only 64% of patients did not have a relapse.
Over the past ten years, surgical methods for treating early stages of breast cancer have fundamentally changed. They have become more conservative. In most cases, with radical irradiation, quite satisfactory cosmetic results are achieved, which are not always possible to obtain with the help of surgical reconstruction. The psychological and sexual aspects of mastectomy surgery become more understandable, and, apparently, the methods of radiation therapy as an alternative to surgical intervention will be further improved.
The question, local resection or mastectomy, can be considered mainly resolved in favor of local resection. To this, both surgeons and patients themselves are inclined. Recently, an important study was conducted in the United States (Eastern Co-operative Oncology Group). A group of elderly women (mean age was more than 70 years) with a diagnosed primary ER-positive tumor in the initial stage (T1N0M0) underwent a local resection operation. If in the future, for 5 years, they received tamoxifen, they did not need to undergo a course of radiation therapy (39). The duration of patient observation plays a critical role, since some of them may already have signs indicating the need for mastextomy, rather than a more conservative local operation.
Such signs include the presence of a large primary tumor or a rather massive tumor in situ, a previous resection with insufficient observance of the principles of ablastics, or a late stage of tumor development. Moreover, the potential side effects of radiation therapy, such as the patient’s feeling of discomfort in the breast, fibrosis of the soft tissues of the chest wall, an increased risk of developing heart disease, as well as a small but significant risk of radiation lung cancer, are becoming increasingly obvious. Fortunately, the radiation doses used now are lower than those for which the listed effects were noted. Therefore, at present, methods of single irradiation of the mammary gland during surgery are being intensively developed. These methods are more convenient for patients and do not require sophisticated equipment required for standard radiotherapy.