Title: Retrospective Comparison of Adjuvant Radiotherapy in Early Stage Breast Cancer and Impact of Delayed PMRT
Authors: Dr Sanjal Kumar.V, Dr S.N. Jagadesh Kumar, Dr Sanjitha, Dr Harishkumar.P
DOI: https://dx.doi.org/10.18535/jmscr/v6i5.38
Abstract
Objectives: To retrospectively evaluate the importance of post mastectomy radiotherapy in early stage breast cancer and impact of timing of starting radiotherapy in terms of local control and disease free survival.
Methodology: This retrospective descriptive study was based on a database of 765 patients who were diagnosed and treated from 2006 to 2012 with 5 years minimum follow up. Patients were divided into three arms
1.ARM I – Patients with T1/2 N0 M0 with no classical indication of PMRT-No PMRT given
- ARM II – Patients with T1/2 N0 M0 with no classical Indication of PMRT who received PMRT
- ARM III - – Patients with T3/4 N+ M0 or with classical
Indication of PMRT who received PMRT
ARM III was subdivided as follows
III A – Patients who received Adjuvant radiotherapy within 6 months of completing surgery
III B – Patients who received Adjuvant radiotherapy after 6 months of completing surgery
Case sheets were scrutinised and data regarding stage, Neoadjuvant chemo, surgery dates, timing of starting radiotherapy ,completion of radiotherapy and toxicity , regular follow ups and if any disease progression the timing of metastasis etc. were collected.
The Kaplan–Meier method was used for calculation and Plotting of the LRFS and DMFS curves of the patient groups, and the Log-rank test was used for the comparison of the survival curves. The results were investigated using the Cox proportional hazards model
Results: ARM I – 92, ARM II – 85, ARM III – 588, III A – 330/588 (56.1%)
III B – 258/588 (43.9%)
Local Recurrence - 17 patients in arm l ,6 patients in arm ll and 47 patients in arm lllB had chest wall recurrence. Regional nodal recurrence was not seen in any of the arms
Distant Metastases- 15 patients in arm l, 11 patients in arm ll and 70 patients in arm lll (23 patients in arm llla and 47 patients in arm lllb) had distant metastases.
Disease Free Survival - DFS in arm l was at an average of 10.14 and median DFS was at 10, DFS in arm ll was at an average of 13.39 and median DFS was at 14, in arm lllA was at an average of 9.3 years and median DFS at 9 years, In arm IIIB was at an average of 8.5 years and median DFS at 9 years, In the whole study, ARM II was significant<p=0.541>in comparison with ARM I and ARM IIIA and IIIB. When you compare ARM IIIA and IIIB, there is no significant difference <p<0.103>.
Conclusions: DFS was significantly better in patients receiving RT compared with those not receiving RT when compared with ARM I and ARM II. Thus signifying some beneficial role in T1-2N0M0 . Timing of initiating pmrt did not affect the disease free survival or overall survival. This is a single institution study further meta-analysis is needed to opine regarding timing of starting Radiotherapy and role of PMRT in early stage breast cancer.
Keywords: adjuvant radiotherapy in breast, post mastectomy radiotherapy, early stage breast cancer, PMRT.
