UNASSIGNED: 94 Background: Intraoperative boost irradiation as part of breast-conserving therapy is a perfect method to adequately capture the high risk @entity5 relapse area. The most homogeneous dose distribution is achieved with electrons. Intraoperative radiotherapy (IOERT) as a boost for @entity0 releases a high single dose of radiation to the breast tissue; therefore acute @entity137 is of particular attention. To date there is only inadequate information available on @entity0 @entity1 treated with IORT using electrons applied as a boost. We therefore analyzed the acute @entity137 and late side effects after radiotherapy with 10 Gy as a boost with a minimum follow-up of 3 months. METHODS: A total of 385 @entity1 treated with IOERT (10 Gy with 5, 7 and 9 MeV electrons) with a dedicated robotic linac (NOVAC 7, New Radiant Technology, Aprilia, Italy) to the @entity5 bed during breast-conserving surgery as a boost followed by whole-breast radiotherapy (WBRT,50- 50.4 Gy; 1.8-2 Gy per fraction) were included in this study. All @entity1 underwent a retrospective follow-up regarding acute and late side effects. @entity137 were documented using the common @entity137 criteria (CTC 4.0 of the European Organization for Research and Treatment of @entity5 ). RESULTS: The IOERT was well tolerated and the cosmetic results were good. As a side effect there were five @entity1 with @entity2080 . Two @entity1 developed a secondary wound healing. Two @entity1 developed @entity1118 in the irradiated breast. Ten @entity1 developed a grade 2 @entity82 . The remaining @entity1 did not develop any grade 3 or 4 side effects. The observed @entity137 rates were not influenced by age, tubus size, electron energy or systemic therapy. 80 @entity1 had a follow up longer than 5 years. Three of them developed distant @entity3 and one @entity1 died. CONCLUSIONS: After IOERT of the breast using electrons we did not find any unexpected acute and late @entity137 rates.

Acute and late side effects for intraoperative electron radiotherapy during breast-conserving surgery of XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity', 'Toxicities'] @entity82 :: ('MESH:D005355', 'Disease') :: ['fibrosis'] @entity0 :: ('MESH:D001943', 'Disease') :: ['breast cancer'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'Cancer'] @entity2080 :: ('MESH:D049291', 'Disease') :: ['seroma'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastasis'] @entity1118 :: ('MESH:D059350', 'Disease') :: ['chronic pain']
@entity0 :: (MESH:D001943,Disease) :: ['breast cancer']
