Purpose/Objective(s)Reducing cardiopulmonary toxicity from breast irradiation continues to be an active area of study. Strategies toward this endeavor have included the reduction of irradiated volume and treatment during deep inspiration breath-hold. This study investigates whether deep inspiration breath-hold (BH) can reduce cardiopulmonary irradiation compared with free breathing (FB) in accelerated partial breast irradiation (APBI).Materials/MethodsBetween December 2005 through February 2008, seven patients with left-sided breast cancers were treated with APBI during deep inspiratory breath-hold. For each patient, both a free breathing scan and a deep inspiratory breath-hold scan were obtained with a GE Lightspeed CT simulator. The Varian Real-time Position Management system was used to obtain breath-hold scans. Typically, four non-coplanar 6MV photon beams were utilized, except for one patient who was treated with a mixed-beam plan of 6MV photons and 9 MeV electrons. All cardiac and left lungs were contoured by a single physician according to NSABP B-39 guidelines for consistency. Retrospectively, each treatment plan was overlaid on the corresponding free-breathing scan obtained at simulation for each patient. Cardiac and left lung doses were compared and analyzed.ResultsPatient characteristics include: age (range, 31-75-years-old), histology (DCIS (n = 2), infiltrating ductal carcinoma (n = 4), invasive mucinous carcinoma (n = 1)), tumor size (0.6-2.9 cm), and location of tumor (superior lateral (n = 5), superior central (n = 1), superior medial (n = 1)). On average, mean and maximum cardiac doses with BH were reduced compared with FB 43.1% (50.6 cGy vs. 95.2 cGy, p = 0.038) and 45.4% (266.2 cGy vs. 518.0 cGy, p = 0.038), respectively (range, reduction in mean cardiac dose: 16.8-68.9%, reduction in maximum cardiac dose: 8.9-74.2%). Cardiac volume decreased with BH versus FB, on average, 11.0% (range, -3.5 to 39.0%). Average reduction in mean left lung dose was 11.3% (235.0 cGy BH vs. 273.5 cGy FB, p = 0.25), while there was minimum change in maximum left lung dose (3,684.1 cGy BH vs. 3476.8 cGy FB). Due to small patient numbers, no definite conclusions could be made regarding the impact from the location of the tumor on cardiopulmonary irradiation.ConclusionsOverall, cardiac and lung doses during APBI treatment appear to be relatively low, and can be reduced further with deep inspiratory breath-hold. Further study and follow-up may clarify the impact of individual cardiac anatomy, tumor location, treatment plan characteristics, and delivered dose on cardiopulmonary toxicity. Purpose/Objective(s)Reducing cardiopulmonary toxicity from breast irradiation continues to be an active area of study. Strategies toward this endeavor have included the reduction of irradiated volume and treatment during deep inspiration breath-hold. This study investigates whether deep inspiration breath-hold (BH) can reduce cardiopulmonary irradiation compared with free breathing (FB) in accelerated partial breast irradiation (APBI). Reducing cardiopulmonary toxicity from breast irradiation continues to be an active area of study. Strategies toward this endeavor have included the reduction of irradiated volume and treatment during deep inspiration breath-hold. This study investigates whether deep inspiration breath-hold (BH) can reduce cardiopulmonary irradiation compared with free breathing (FB) in accelerated partial breast irradiation (APBI). Materials/MethodsBetween December 2005 through February 2008, seven patients with left-sided breast cancers were treated with APBI during deep inspiratory breath-hold. For each patient, both a free breathing scan and a deep inspiratory breath-hold scan were obtained with a GE Lightspeed CT simulator. The Varian Real-time Position Management system was used to obtain breath-hold scans. Typically, four non-coplanar 6MV photon beams were utilized, except for one patient who was treated with a mixed-beam plan of 6MV photons and 9 MeV electrons. All cardiac and left lungs were contoured by a single physician according to NSABP B-39 guidelines for consistency. Retrospectively, each treatment plan was overlaid on the corresponding free-breathing scan obtained at simulation for each patient. Cardiac and left lung doses were compared and analyzed. Between December 2005 through February 2008, seven patients with left-sided breast cancers were treated with APBI during deep inspiratory breath-hold. For each patient, both a free breathing scan and a deep inspiratory breath-hold scan were obtained with a GE Lightspeed CT simulator. The Varian Real-time Position Management system was used to obtain breath-hold scans. Typically, four non-coplanar 6MV photon beams were utilized, except for one patient who was treated with a mixed-beam plan of 6MV photons and 9 MeV electrons. All cardiac and left lungs were contoured by a single physician according to NSABP B-39 guidelines for consistency. Retrospectively, each treatment plan was overlaid on the corresponding free-breathing scan obtained at simulation for each patient. Cardiac and left lung doses were compared and analyzed. ResultsPatient characteristics include: age (range, 31-75-years-old), histology (DCIS (n = 2), infiltrating ductal carcinoma (n = 4), invasive mucinous carcinoma (n = 1)), tumor size (0.6-2.9 cm), and location of tumor (superior lateral (n = 5), superior central (n = 1), superior medial (n = 1)). On average, mean and maximum cardiac doses with BH were reduced compared with FB 43.1% (50.6 cGy vs. 95.2 cGy, p = 0.038) and 45.4% (266.2 cGy vs. 518.0 cGy, p = 0.038), respectively (range, reduction in mean cardiac dose: 16.8-68.9%, reduction in maximum cardiac dose: 8.9-74.2%). Cardiac volume decreased with BH versus FB, on average, 11.0% (range, -3.5 to 39.0%). Average reduction in mean left lung dose was 11.3% (235.0 cGy BH vs. 273.5 cGy FB, p = 0.25), while there was minimum change in maximum left lung dose (3,684.1 cGy BH vs. 3476.8 cGy FB). Due to small patient numbers, no definite conclusions could be made regarding the impact from the location of the tumor on cardiopulmonary irradiation. Patient characteristics include: age (range, 31-75-years-old), histology (DCIS (n = 2), infiltrating ductal carcinoma (n = 4), invasive mucinous carcinoma (n = 1)), tumor size (0.6-2.9 cm), and location of tumor (superior lateral (n = 5), superior central (n = 1), superior medial (n = 1)). On average, mean and maximum cardiac doses with BH were reduced compared with FB 43.1% (50.6 cGy vs. 95.2 cGy, p = 0.038) and 45.4% (266.2 cGy vs. 518.0 cGy, p = 0.038), respectively (range, reduction in mean cardiac dose: 16.8-68.9%, reduction in maximum cardiac dose: 8.9-74.2%). Cardiac volume decreased with BH versus FB, on average, 11.0% (range, -3.5 to 39.0%). Average reduction in mean left lung dose was 11.3% (235.0 cGy BH vs. 273.5 cGy FB, p = 0.25), while there was minimum change in maximum left lung dose (3,684.1 cGy BH vs. 3476.8 cGy FB). Due to small patient numbers, no definite conclusions could be made regarding the impact from the location of the tumor on cardiopulmonary irradiation. ConclusionsOverall, cardiac and lung doses during APBI treatment appear to be relatively low, and can be reduced further with deep inspiratory breath-hold. Further study and follow-up may clarify the impact of individual cardiac anatomy, tumor location, treatment plan characteristics, and delivered dose on cardiopulmonary toxicity. Overall, cardiac and lung doses during APBI treatment appear to be relatively low, and can be reduced further with deep inspiratory breath-hold. Further study and follow-up may clarify the impact of individual cardiac anatomy, tumor location, treatment plan characteristics, and delivered dose on cardiopulmonary toxicity.