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Journal of Medical Physics and Applied Sciences
ISSN: 2574-285X
I n t e r n a t i o n a l C o n f e r e n c e o n
Nuclear Medicine &
Radiation Therapy
Nuclear Medicine & Radiation Therapy 2018
O c t o b e r 0 1 - 0 2 , 2 0 1 8
S t o c k h o l m , S w e d e n
Breast carcinoma: impact of respiratory gating in cardiac
dose reduction
Raul da Silva Colaco, A Matos, J Fonseca, I Antao, T Madaleno,
J Santos, A Barateiro, M Sousa, A Mota and F Santos
Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), Portugal
Biography
Raul da Silva Colaço is a Medical Doctor and has completed
his studies at Nova Medical School Lisbon in 2015. He is
currently in his second year of Residency in Radiation Oncology
at Instituto Português de Oncologia which began in 2017.
Over the past years, he has presented several posters and oral
communications in national conferences.
rs.colaco@gmail.comIntroduction:
There is evidence of the importance of dose reduction on the heart
due to the association between mean heart dose (Mean HD) and major coronary
events in patients who underwent adjuvant radiotherapy for early breast cancer of
the left breast (EBCLB). Efforts have been made to reduce the rates of late toxicity
and respiratory gating techniques, especially deep inspiration breath hold (DIBH)
has shown promising results.
Objectives:
Quantify and compare Mean HD and maximum heart dose (Maximum
HD) in EBCLB patients using deep inspiration breath-hold (DIBH) vs free breathing
(FB). Evaluate the presence of major adverse cardiovascular events (MACE).
Materials & Methods:
From 13th Oct’ 2016 to 30th Jun’ 2018, 14 patients with
EBCLB underwent planning CT scans with FB and DIBH, using real-time position
management system. Both scans were used for planning and two dosimetries
were generated to evaluate Mean HD and Maximum HD for each patient. MACE
was evaluated trough the observation of hospital records.
Results:
14 women with the median age of 57 years underwent external beam
radiation therapy with conventional fractionation (median dose 60Gy), the
comparison of DIBH and FB plans showed a reduction on mean HD (3.7 Gy vs 7.1
Gy) andMaximumHD (40.7 Gy vs 49.5 Gy). MACE was evaluated in 10 patients, no
MACE was observed; the median follow up was till 16 months.
Discussion:
The observed reductions in mean HD and maximum HD can be
explained by the displacement of the treated volume relative to the heart.
According to published data, the 3.4 Gy reductions in the mean HD represent a
reduction in the risk of MACE of 25.2%. MACE events were not recorded in this
sample; however a longer follow up is necessary to evaluate the impact of these
cardiac dose reductions.
Conclusion:
The use of DIBH on EBC has shown a significant reduction on the
mean HD and maximumHD. The observed results may contribute to a decrease in
the probability of MACE.
Raul da Silva Colaco et al., J. med phys & appl sci 2018, Volume: 3
DOI: 10.21767/2574-285X-C1-002