Eight studies (n=353) evaluating IORT were identified: one RCT (n=70), one cohort study (n=101), 5 case series (n=181), and one case report (n=1).
Nine studies evaluating BCT were identified: 8 RCTs and one systematic review. The total number of participants in each of the comparator studies was not given in the report, as only data on those receiving BCT were extracted; the authors considered these studies to be case series to provide 'bench mark' information.
Safety.
None of the IORT or BCT studies included in the review reported on peri-operative morbidity or peri-operative mortality.
Post-operative morbidity or complications.
Comparative IORT studies (1 RCT and 1 cohort): the RCT found that 2.9% of the patients given IORT had wound infections; the rate of wound infections for non-IORT patients was not given. In addition, 4.3% of the patients in the study had seroma development, although it was unclear whether these patients were in the IORT or non-IORT treatment group. The cohort study found no statistically significant difference in healing time, lymphocoele development, or the length of hospital stay between IORT and non-IORT patients. Sclerosis developed in 11.6% of those patients given IORT; the results for non-IORT patients were not provided.
Non-comparative IORT studies: 4 case series were identified. One study found that wound infections occurred in 4% of the patients given IORT, evidence of delayed healing occurred in 8%, and 12% experienced short-term erythema. In a further study, 7.4% of the patients experienced delayed healing, 14.8% developed mastitis, and one patient with delayed healing also developed a lymphocoele. Two of the included studies found that palpable fibroses developed in 9.5% and 6% of the patients given IORT. One study reported that oedema occurred in 3% of patients given IORT, while 2% reported pain at their lumpectomy site. A further study found that 4.2% of the patients had a mild residual breast defect following IORT.
BCT comparator studies (2 RCTs; data provided on BCT patients only): one study found that 13% of the patients given BCT reported haematoma and 17% developed surgical wound infections; the other study found that 12.4% of the patients given BCT experienced post-operative telangiectasia.
Efficacy. Cosmetic outcomes.
Comparative IORT studies (1 RCT and 1 cohort study): in the RCT (n=70), post-operative cosmesis was rated as 'good to excellent' in 80% of the patients who were given IORT and 76% of the non-IORT patients. In the cohort study, the cosmetic outcome of all patients who were given IORT were rated as 'excellent' and 88.4% had 'no visible sequelae'; however, the results of the control group were not given.
Non-comparative IORT studies: 3 case series were found. One study found that most patients who were given IORT rated their cosmetic outcome as 'better than expected'. Another study (n=7) reported that 71.4% of the patients had visible scarring but all were satisfied with their cosmetic outcome. A further study reported that 6% of the patients developed disfiguring fibroses that affected breast cosmesis.
BCT comparator studies (3 RCTs; data provided on BCT patients only): post-operative cosmesis was rated by clinicians as 'excellent' or 'satisfactory' in 72% of a small sample of patients in one study, and by patients as 'good to excellent' in 85% and 87% of patients in two further studies.
Local cancer recurrence.
Comparative IORT studies (1 cohort study): no patients given IORT had a local recurrence at 2 years' follow-up; no data for the control group were given.
Non-comparative IORT studies (3 case series, 1 case report): the rate of local recurrence ranged from 0% at 1.5 year' follow-up to 29% at 10.3 years' follow-up (10.3-year follow-up data were available for 7 patients).
BCT comparator studies (8 RCTs, 1 systematic review; BCT patients only): the rate of local recurrence ranged from 3.3% at 10 years' follow-up to 19.7% at 13.4 years' follow-up.
Disease-free survival.
No IORT studies reported disease-free survival. However, all of the included BCT comparator studies derived Kaplan-Meier survival estimates or crude survival rates. The Kaplan-Meier estimates ranged from 86% at 5 years to 70% at 6 years, and the crude rates ranged from 51.1% at 10 years to 87% at 5.1 years.
Overall survival.
Comparative IORT studies: no IORT comparative study reported on overall survival.
Non-comparative IORT studies (3 case series): overall survival ranged from 86% at 10.3 years (based on 7 patients) to 100% (duration of follow-up unknown).
BCT comparator studies (8 RCTs, 1 systematic review; BCT patients only): overall survival ranged from 92.9% at the 5-year follow-up to 62% at the 15-year follow-up.