When breast cancer is surgically excised, it can come back (local recurrence) in the remaining breast or on the chest wall in a small proportion of women. Adjuvant radiotherapy is necessary if breast cancer is treated by removing only the cancerous lump with a rim of surrounding normal tissue, as it reduces the chance of local recurrence significantly . When cancer does come back, it most commonly occurs in the tissues surrounding the original cancer (the tumour bed), even though there are multicentric cancers in remote areas of the breast. This suggests that it is most important to treat the tumour bed. The rationale for TARGIT is to deliver a high dose of radiation precisely to the tumour bed. Conventional radiation techniques such as external beam radiotherapy (EBRT) following surgical removal of the tumour have been time tested and proven to be effective. EBRT is usually given as a course of whole breast radiotherapy and an additional tumour bed boost  . However, it has a few drawbacks; for example, the tumour bed where the boost dose should be applied can be missed ("geographical miss") due to the difficulties in localization of the complex wound cavity  even when modern radiotherapy planning is used. Additionally, the usual delay ("temporal miss") between the surgical removal of the tumour and EBRT may allow a repopulation of the tumour cells  . These potentially harmful effects can be avoided by delivering the radiation more precisely to the targeted tissues leading to immediate sterilization of residual tumour cells. Furthermore, TARGIT inhibits the stimulating effects of wound fluid on cancer cells, suggesting for the first time, a beneficial effect of intraoperative radiotherapy (IORT) on tumour microenvironment. In these studies, women treated with  TARGIT-IORT  during lumpectomy for breast cancer combined with whole breast radiotherapy had a significantly low mortality from non-breast-cancer causes, such as cardiovascular and lung complications, as well as other cancers compared with those who received whole breast radiotherapy. Therefore, this reduction was thought to be due to the delivery of TARGIT-IORT to the fresh tumour bed during the trauma of surgery rather than avoidance of scattered radiation from whole breast radiotherapy .
When breast cancer is surgically excised, it can come back (local recurrence) in the remaining breast or on the chest wall in a small proportion of women. Adjuvant radiotherapy is necessary if breast cancer is treated by removing only the cancerous lump with a rim of surrounding normal tissue, as it reduces the chance of local recurrence . When cancer does come back, it most commonly occurs in the tissues surrounding the original cancer (the tumour bed), even though there are multicentric cancers in remote areas of the breast. This suggests that it is most important to treat the tumour bed. The rationale for TARGIT is to deliver a high dose of radiation precisely to the tumour bed. Conventional radiation techniques such as external beam radiotherapy (EBRT) following surgical removal of the tumour have been time tested and proven to be effective. EBRT is usually given as a course of whole breast radiotherapy and an additional tumour bed boost , or partial breast irradiation of a smaller area . However, it has a few drawbacks; for example, the tumour bed where the boost dose should be applied can be missed due to the difficulties in localization of the complex wound cavity ("geographical miss"), even when modern radiotherapy planning is used. Additionally, the usual delay between the surgical removal of the tumour and EBRT may allow a repopulation of the tumour cells ("temporal miss") . These potentially harmful effects may be avoided by delivering the radiation more precisely to the targeted tissues leading to immediate sterilization of residual tumour cells. The use in TARGIT of a small treatment device which can be positioned in close physical proximity to the treatment site aims to avoid some of these practical issues. TARGIT irradiation has also been shown to affect the properties of wound fluid, which may be linked to cancer cell proliferation and possibly local recurrence. The TARGIT technique is the subject of clinical trials. A major phase III trial comparing TARGIT-IORT to EBRT during lumpectomy for breast cancer completed in 2012, with long-term follow-up ongoing .
D
significantly
A
, or partial breast irradiation of a smaller area
D
("geographical miss")
A
("geographical miss"),
D
("temporal miss")
A
("temporal miss")
R
can
may
R
Furthermore, TARGIT inhibits the stimulating effects of wound fluid on cancer cells, suggesting for the first time, a beneficial effect of intraoperative radiotherapy (IORT) on tumour microenvironment. In these studies, women treated with
The use in TARGIT of a small treatment device which can be positioned in close physical proximity to the treatment site aims to avoid some of these practical issues. TARGIT irradiation has also been shown to affect the properties of wound fluid, which may be linked to cancer cell proliferation and possibly local recurrence.
A
The TARGIT technique is the subject of clinical trials. A major phase III trial comparing
A
to EBRT
R
combined with whole breast radiotherapy had a significantly low mortality from non-breast-cancer causes, such as cardiovascular and lung complications, as well as other cancers compared with those who received whole breast radiotherapy. Therefore, this reduction was thought to be due to the delivery of TARGIT-IORT to the fresh tumour bed during the trauma of surgery rather than avoidance of scattered radiation from whole breast radiotherapy
completed in 2012, with long-term follow-up ongoing