The sequence of hormonal therapy with adjuvant radiation(RT) is debated because of anticipated morbidity. We conducted a phase II study to evaluate feasibility and efficacy of concurrent and sequential letrozole along-with hypo-fractionated RT(HFRT).
A total of 50 Post-menopausal women with hormone-receptor positive, Stage I-III Breast cancer received adjuvant HFRT 42.5Gy/16fr/3weeks and were randomly assigned to either concurrent (arm A) or sequential letrozole (arm B). Letrozole was started 3 weeks before RT in the concurrent, and 3 weeks after RT in sequential group. Pulmonary toxicity was assessed by clinical examination, chest x-ray, pulmonary function tests and HRCT chest (if indicated) at baseline, at one and six months(m) post RT. Cosmetic outcome was reported in both arms with six parameters (Table) at 6 m post RT.
A total of 48 patients(pts) were followed up for 6 m (25 in Arm A and 23 in Arm B). None of the pts developed acute pulmonary toxicities. Mean (R) FeV1 and FVC values at baseline, 1 and 6 m post RT were 1.8 l (1.6-1.9) and 2.2 l(2.1-2.4), 1.79 l(1.5-1.9) and 2.1 l(1.9-2.4) and 1.85 l(1.6-2) and 2.2 l(2-2.4) respectively, and were comparable. FeV1 and FVC remained within 80 to 120% of the baseline values in 37 pts (20 Arm A vs 17 Arm B, p = 0.5). FeV1 and FVC were reduced by more than 80% at 6 m in 3 pts of Arm A and 5 pts in Arm B, (p = 0.7), while this was improved by over 120% in 5 pts (2 vs 3, p = 1). RTOG grade 2-3 radiation dermatitis was seen in 33 pts (15 vs 18, p = 0.55) while 5 pts had grade 4 toxicity (2 vs 3, p = 1). There was no treatment interruption because of toxicity.Table:
|Mild change||Marked change|
|ARM A||ARM B||ARM A||ARM B|
|Change in Skin appearance||9||8||3||3|
|Photographic breast assessment||15||15||3||2|
Overall, 18 pts had excellent cosmesis (7 vs 11, p = 0.4) while 32 had good cosmesis. (18 vs 14, p = 0.4).
HFRT along-with concurrent Letrozole is well tolerated. However, patients are being followed to assess loco-regional disease control and late toxicities.
Clinical trial identification
Legal entity responsible for the study
All India Institute of Medical Sciences
All authors have declared no conflicts of interest.