الفهرس 
Early breast cancer, the biology of the disease and implications formanagementOnly 14 pages are availabe for public view
 |  | from | 237 |  |  |
| | | from | 237 | | |
Abstract
Acute and subacute cardiac complications caused by PMRT, such as pericarditis and cardiac failure, have been reported infrequently. [Pierce et al. 1992] Long-term complications, notably an increase in cardiac-related mortality, has been reported more commonly.[kreisman and Wolkove 1992] Registry-based studies also have demonstrated an increase in cardiac mortality for patients treated with left-sided breast cancers.[Paszat, 1998 and Rutqvist et al, 1990] This increase in cardiac deaths has been attributed primarily to ischemic heart disease. This was most clearly demonstrated by a meta-analysis of 10 randomized trials of PMRT initiated before 1975 when older techniques of radiotherapy were used. The standard mortality ratio for heart disease was 1.62 times higher for irradiated patients than for the unirradiated patients [P=0.01]. These findings were confirmed in the larger Oxford overview of radiotherapy trials, which included patients treated with breast-conserving surgery as well. [EBCTCG, 1995 and 2003]
Assessing the risk of long-term cardiac toxicity due to PMRT is complex due to the long latency for such side effects and the possible contribution of patient-related factors, as well as treatment factors.
Perhaps the most important treatment factor is the volume of heart irradiated. Many techniques used to irradiate the internal mammary nodes (such as the pure photon “hockey-stick” field) included large cardiac volumes, regardless of whether the tumour was left- or right-sided. [Pierce et al. 1992]
In the present study internal mammary nodal irradiation was not used, and among those who had left breast irradiation only 1 patient had part of the heart involved in the tangential field and this was less than 1 cm thickness. Thus there was less anticipated risk of cardiac morbidities.
None of the studied cases had symptoms or signs of acute cardiac morbidity. 1 patient [8%] had decline of the left ejection fraction yet this patient was on adjuvant therapy with Trastuzumab which is more likely to be the cause of this finding.
It is difficult to assess cardiac morbidity particularly from studies as the present one with relatively short follow up period due to the long latency for such side effects which may extend to 20 years.
Although this study was trying to address the question of how the process objectives of postmastectomy radiation therapy are met after immediate breast reconstruction, it was not de- signed to assess the impact of this effect on local regional control or survival rates. The mean follow up here was 14.4 months. Most studies demonstrating low risk of locoregional failures after mastectomy and immediate reconstruction have had longer follow-up periods.
Larger studies with larger number of patients and longer term follow up are required to assess cardiac morbidity, locoregional failure and survival data.