Tumor bed boost in breast cancer: Brachytherapy versus electron beam

Abstract

Background:The prospective study aimed to evaluate the effectiveness of Electron beam or HDR 192Ir Interstitial Implant used as a boost in breast Conservation cases after completion of EBRT. The two therapeutic modalities were compared in terms of the following parameters; i.e. cosmesis, optimization of tumor bed boost, local control, toxicity, and DFS.Materials and Methods:The EBRT dose used was 50 Gy in 25 fractions over 5 weeks time. Target delineation of boost treatment was done by CT scan or by high resolution USG. EBRT will be immediately followed by local boost at the primary tumor bearing site of breast with 8 to12 MeV electron beam to a dose of 15 Gy in 6 fractions (Arm A) or with HDR 192Ir interstitial brachytherapy to a dose of 15 Gy in 3 fractions at 6 hours apart (Arm B).Results:The excellent cosmesis achieved with electron beam therapy in Arm A was found to be statistically significant (P = 0.025). Local relapse was absent in both the arms. One distant metastasis occurred in Arm A within 10 months of initiation of treatment and one distant metastasis in Arm B came out within 3 months of starting of therapy.Conclusion:The study has shown good cosmetic result with electron boost and 100% local control with both the technique. However if there is a more number of patients with longer period of follow up we could have got the actual picture to verify our results and assess long term survival data.

Biosimilarity and Interchangeability: Principles and Evidence: A Systematic Review

“…Treatment discontinuation because of AE, CD: 2 patients (arthralgia, fibrous dysplasia in maxilla); UC: 2 patients (lack of response)ADA positive: 9.5 vs 6% ( P  = 0.54Park et al 2015 [59]With IBD ( N  = 173)60INX RP, duration: NR (study also included naive patients started straight on CT-P13 treatment, with no switch)CT-P13, duration: 30 weeksDisease worsened (remission not maintained/achieved) in 11% of patients in switch group during 30-week follow-upTreatment-related TEAEs of special interest, n for naive vs switch, anaphylactic reaction: 0 vs 1; tuberculosis: 1 vs 0; infusion-related reaction: 0 vs 3; no cases of pneumonia or malignancyNRRubio et al 2016 (abstract) [64]With rheumatic diseases ( N  = 78)53INX RP (Remicade ® ), duration NR (study also included naive patients started straight on biosimilar INX, with no switch)Biosimilar INX (Remsima ® ), follow-up 9 months4 patients (5%) in switch group and 1 patient (4%) in naive group discontinued because of loss of efficacyIn switch group, 1 patient discontinued because of cutaneous leishmaniasis. In naive group, 1 patient each discontinued because of photosensitivity, bronchospasm, urticariaNRHörbrand et al 2013 [76]With CKD ( N  = 6177)507Originator short-acting epoetin alfa, epoetin beta, epoetin delta, epoetin theta, long-acting darbepoetin alfa, methoxy polyethylene glycol epoetin beta, duration ≥ 3 monthsBiosimilar short-acting epoetin alfa, epoetin zeta, duration ≥ 3 monthsNo change in median defined daily doses consumption when switchedNRNRMinutolo et al 2016 [78]Under-going haemodialysis ( N  = 149)149Reference epoetin, darbepoetin, duration NR (analysis 12 weeks)Biosimilar epoetin (HX575, SB309), duration 24 weeksBaseline vs post-switch, haemoglobin: 11.1 g/dL vs 11.0 g/dL ( P NS); dose: 8765 IU/week vs 10,886 IU/week ( P  = 0.001)NRNROhta et al 2014 [80]With renal anaemia ( N  = 30)30Epoetin beta, duration 3 monthsEpoetin kappa, duration 3 monthsHaemoglobin levels predominantly stable (shown graphically, statistical analysis NR)NRNRRoy et al 2013 […”

“…All seven observational studies that did not include reasons for switching assessed efficacy parameters after switching compared with baseline/before switching (Table 3) [57, 59, 64, 76, 78, 80, 100]. Three involved infliximab [57, 59, 64], three ESAs [76, 78, 80] and one rituximab [100].…”

“…In one of these studies, on ESAs in patients on haemodialysis, switching to a biosimilar resulted in higher mean drug dose requirements (from 8765 to 10,886 IU/week; P  < 0.05) to maintain haemoglobin levels [78]. Of the five studies not reporting a formal statistical analysis of between-group comparisons, four reported that switching had no noticeable effect [64, 76, 80, 100] and one reported disease worsening in five of 46 evaluable patients with IBD (11%) during 30 weeks of follow-up after switching from infliximab originator to biosimilar [59]. …”

“…In terms of safety data after switching, one study reported similar patterns to before switching [57], one (in patients with IBD) reported three cases of infusion reaction and one of pneumonia in the switch group, which comprised 60 patients (vs none in the treatment-naive group, which comprised 113 patients) [59], one reported adverse events (cutaneous leishmaniasis) only when these were a reason for treatment discontinuation [64], and four studies did not report safety data [76, 78, 80, 100]. …”

“…These differences need to be taken into account when interpreting results from switching studies. Almost all of the studies identified for inclusion in the current review originated from highly regulated markets, with the exception of seven studies that included emerging markets [75, 83, 87, 93, 94, 99, 100], of which six reported similar outcomes for switched and non-switched groups and one, from South Africa, reported a requirement for increased insulin dose post-switch [87]. …”