Cardiac perfusion changes in patients treated for breast cancer with radiation therapy and doxorubicin: preliminary results.
OBJECTIVE
To determine the incidence and dose dependence of regional cardiac perfusion abnormalities in patients with left-sided breast cancer treated with radiation therapy (RT) with and without doxorubicin (Dox).


METHODS
Twenty patients with left-sided breast cancer underwent cardiac perfusion imaging using single photon emission computed tomography (SPECT) prechemotherapy, pre-RT, and 6 months post-RT. SPECT perfusion images were registered onto 3-dimensional (3D) RT dose distributions. The volume of heart in the RT field was quantified, and the regional RT dose was calculated. A decrease in regional cardiac perfusion was assessed subjectively by visual inspection and objectively using image fusion software. Ten patients received Dox-based chemotherapy (total dose 120-300 mg/m(2)), and 10 patients had no chemotherapy. RT was delivered by tangent beams in all patients to a total dose of 46-50 Gy.


RESULTS
Overall, 60% of the patients had new visible perfusion defects 6 months post-RT. A dose-dependent perfusion defect was seen at 6 months with minimal defect appreciated at 0-10 Gy, and a 20% decrease in regional perfusion at 41-50 Gy. One of 20 patients had a decrease in left ventricle ejection fraction (LVEF) of greater than 10% at 6 months; 2/20 patients had developed transient pericarditis. No instances of myocardial infarction or congestive heart failure (CHF) have occurred.


CONCLUSIONS
RT causes cardiac perfusion defects 6 months post-RT in most patients. Long-term follow-up is needed to assess whether these perfusion changes are transient or permanent and to determine if these findings are associated with changes in overall cardiac function and clinical outcome.
Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA.
P H
PH
Hardenbergh
M T
MT
Munley
G C
GC
Bentel
R
R
Kedem
S
S
Borges-Neto
D
D
Hollis
L R
LR
Prosnitz
L B
LB
Marks
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000503:physiopathology / Q000532:radiotherapy*; D003131:Combined Modality Therapy; D003326:Coronary Circulation / Q000187:drug effects* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004317:Doxorubicin / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods; D006321:Heart / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000528:radiation effects*; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D016277:Ventricular Function, Left / Q000187:drug effects / Q000528:radiation effects
D000970:Antineoplastic Agents; D004317:Doxorubicin