|LETTER TO EDITOR
|Year : 2021 | Volume
| Issue : 3 | Page : 602-603
Extending adjuvant endocrine therapy in hormone receptor-positive breast cancer: An Indian perspective
Shuvadeep Ganguly, Ajay Gogia
Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India
|Date of Submission||26-Aug-2021|
|Date of Decision||02-Sep-2021|
|Date of Acceptance||05-Sep-2021|
|Date of Web Publication||08-Oct-2021|
Department of Medical Oncology, Dr. B.R.A. Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi - 110 029
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Ganguly S, Gogia A. Extending adjuvant endocrine therapy in hormone receptor-positive breast cancer: An Indian perspective. Cancer Res Stat Treat 2021;4:602-3
|How to cite this URL:|
Ganguly S, Gogia A. Extending adjuvant endocrine therapy in hormone receptor-positive breast cancer: An Indian perspective. Cancer Res Stat Treat [serial online] 2021 [cited 2021 Dec 9];4:602-3. Available from: https://www.crstonline.com/text.asp?2021/4/3/602/327789
For women with early hormone receptor-positive breast cancer, the optimal duration of adjuvant hormonal therapy remains debatable. Among post-menopausal women, the choice between tamoxifen and aromatase inhibitors and the proper strategy of sequencing them is also unclear. As there is a persistent risk of recurrence of breast cancer even 5 years after the initial diagnosis, studies have evaluated the benefit of extending adjuvant endocrine therapy; the salient findings of some of these studies are summarized in [Table 1].,,,
|Table 1: Comparative studies evaluating different strategies of extending adjuvant hormonal therapy|
Click here to view
A patient level meta-analysis suggested that the benefit of aromatase inhibitors in preventing recurrence was more than that of tamoxifen, especially in the initial duration of adjuvant therapy. However, on extended use, it is unclear whether this benefit is offset by an increased burden of adverse events. It was conclusively observed in the ATLAS trial that extending the duration of adjuvant tamoxifen from 5 to 10 years not only decreased the breast cancer recurrence rate and prolonged survival, but the effect was more pronounced in the second decade after the completion of therapy. On the other hand, studies which evaluated the benefit of extending the duration of aromatase inhibitors, failed to demonstrate an overall survival advantage [Table 1].,, Indeed, in the recent study by Gnant et al. among post-menopausal women with early hormone receptor positive breast cancer post 5 years of adjuvant endocrine therapy, there was no benefit of extending the use of aromatase inhibitors for 5 years over 2 years.
The use of aromatase inhibitors for an extended duration is also associated with clinically significant adverse events, especially an increased incidence of osteoporosis and bone fractures.,, It is important to note that aromatase inhibitors affect the patient's quality of life and may accelerate neurocognitive decline. Poor adherence to therapy also remains a potential concern with 33% patients discontinuing therapy by 5 years in the trial by Gnant et al.
In India, the breast cancer incidence peaks at 45–49 years of age, a whole decade earlier than in the Western population. Vitamin D deficiency is also prevalent in a significant proportion of the population,, which makes the skeletal adverse effects of aromatase inhibitors more concerning. Considering the above factors, as well as the challenges in ensuring good compliance to aromatase inhibitors, the use of tamoxifen as the choice for adjuvant endocrine therapy appears reasonable, especially in the Indian context. The overall survival advantage of adjuvant tamoxifen as well as the carry-over effect of protection against breast cancer recurrence even after the completion of therapy makes it a more attractive option.
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Conflicts of interest
There are no conflicts of interest.
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