Skeletal Events of Hormonal Treatment and Radiotherapy in Patient With Breast Cacer

study of lymphedema and skeletal events in breast cacer patient receiving adjuvant hormonal therapy and radiothearpy

In the United States, it is estimated that there are more than 3.8 million living women has a history of invasive breast cancer, and 268,600 women will be newly diagnosed in 2019. Sixty-four percent of breast cancer survivors (more than 2.4 million women) are ≥ 65 years, whereas 7% are aged younger than 50 years 1.

The most common treatment of early stage (stage I or II) breast cancer is breast-conserving surgery (BCS) with adjuvant radiation therapy (49%) and 34% of patients undergo mastectomy. In contrary, more than two-thirds (68%) of patients with stage III disease undergo mastectomy and most of them receive adjuvant chemotherapy 2.

Some of the most debilitating morbidity after surgery and radiotherapy for breast cancer is related to treatment of the axilla. This includes persistent arm lymphoedema, impaired shoulder mobility and brachial plexopathy. Other exogenous factors have an influence on the risk of radiotherapy-related morbidity as patients' age and obesity 3.

Lymphedema of the arm occurs in 19.9% of women who undergo axillary lymph node dissection and in 5.6% of women who have a sentinel lymph node biopsy 4. Irradiation of the regional lymph nodes may increase the risk, especially among patients receiving axillary lymph node dissection 5.

Early diagnosis of lymphedema is important for optimizing its treatment and preventing its progression 6. Some forms of cancer rehabilitation may reduce the risk and lessen the severity of this condition 7, 8.

Treatment with adjuvant aromatase inhibitors (AI), which is generally reserved for postmenopausal women, can cause osteoporosis 9.

Osteoporosis, a process of bone mineral density (BMD) reduction, is accelerated by estrogen deficiency in postmeno¬pausal women. Tamoxifen reduces BMD in premenopausal women, while promotes bone formation in postmenopausal patients. On the other hand, adjuvant aromatase inhibitors (AIs) therapy enhances the BMD decrease to about 2.5% per year, due to a long lasting significant deprivation of circula¬tory and tissue estrogens 10. In the bone companion study of the MA.17 trial, patients treated with anastrozole reported a significant decreases in BMD (\~4%), compared to those treated with tamoxifen 11.

Dual energies' X ray absorptiometry (DXA) scan is the current validated 'gold standard' for the diagnosis of osteoporosis, fracture risk estimation and follow up of anti osteoporotic treatment 12-14, since it is non invasive, simple, precise, fast, less expensive than other imaging techniques, including computed tomography and magnetic resonance imaging, and more sensitive than quantitative ultrasound (QUS) 15.

Eligibility Criteria:
Inclusion Criteria:

* Postmenopausal patients with positive diagnosis of stage 1-3 breast cancer and planned AI (anastrazole, letrozole) adjuvant treatment will be included in the study.
* Patients without known osteoporosis will included in the study, and before AI treatment began.
* Conventional RT course must be completed (50 Gy/25 fractions, 2 Gy/fraction, 5 days/week).
* Patients continue to receive adjuvant hormonal treatment (aromatase inhibitors) or adjuvant target therapy (trastuzumab) while monitoring late toxicities

Exclusion Criteria:

* Male patients
* Metastatic disease at presentation
* No definitive surgery
* Carcinoma in situ or other rare tumors of the breast as phyllodes tumors.