Comparing the long-term effectiveness of integrated IMRT vs segmented 3D-CRT after modified breast removal surgery in breast cancer patients

This study compared the long-term effectiveness of integrated intensity-modulated radiation therapy (IMRT) and segmented 3D-conventional radiotherapy (3D-CRT) following breast-removal surgery (radical mastectomy) in patients with breast cancer (BC). The data showed that integrated IMRT reduced the recurrence rate in the long-term with manageable side effects when compared to segmented 3D-CRT.

Surgery such as the total removal of the breast (mastectomy) or breast-conserving surgery (BCS) is a main treatment for patients with BC. BCS involves the removal of the tumor only, with the preservation of the breast. During a radical mastectomy, underlying chest muscle and lymph nodes are removed with the whole breast.

Radiation therapy (RT) is commonly used following surgery to destroy any remaining cancer cells. This prevents the cancer from coming back (recurrence). Advanced radiation treatments such as three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) have been shown to better distribute the dose of radiation and better protect normal tissue.

3D-CRT is a technique where the radiation beam is shaped to match the cancer so it will not affect the healthy surrounding tissue. IMRT is an advanced type of "high-precision" radiation therapy. With IMRT, hundreds of irradiating beams are used, and each beam of radiation can be individually programmed to a different intensity. IMRT has been widely used in patients with BC after modified radical mastectomy (MRM). However, the long-term outcomes and side effects in patients treated with integrated IMRT and segmented 3D-CRT after MRM are still unknown.

This study involved 223 patients with BC. These patients previously underwent MRM and were recommended RT. Patients were divided into 2 groups. Group 1 included 129 patients who received integrated IMRT. Group 2 included 94 patients who received segmented 3D-CRT. The average follow-up time was 104.3 months.

86% for patients in group 1 were free of disease after 8 years compared to 73.4% for patients in group 2. After 8 years, 91.4% of patients in group 1 and 86.2% of group 2 were alive.

2.3% of women who were treated with integrated IMRT experienced local recurrence (coming back of the cancer) compared to 7.4% of women who were treated with segmented 3D-CRT. No significant difference was observed in late side-effects between the two groups.

This study concluded that integrated IMRT reduced the recurrence rate in the long-term in patients with BC following MRM compared to segmented 3D-CRT.

This study included a small group of patients. Also, the study was based on data from medical records. Patients were not randomly assigned to each group. This might have affected the results.