What are the uses of Letrozole (Femara)?

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From the Guidelines

Letrozole (Femara) is primarily used in the treatment of hormone receptor-positive breast cancer in postmenopausal women.

Uses of Letrozole

  • Adjuvant therapy: Letrozole is used as an adjuvant therapy in postmenopausal women with hormone receptor-positive breast cancer, either as initial therapy or after tamoxifen therapy 1.
  • Extended therapy: Letrozole can be used as extended therapy after 4.5 to 6 years of tamoxifen therapy in postmenopausal women with hormone receptor-positive breast cancer, particularly in those with axillary lymph node-positive disease 1.
  • First-line treatment: Letrozole can be used as first-line treatment in postmenopausal women with hormone receptor-positive, HER2-negative advanced breast cancer, in combination with a CDK 4/6 inhibitor 1.
  • Sequential therapy: Letrozole can be used as sequential therapy after 2 to 3 years of tamoxifen therapy in postmenopausal women with hormone receptor-positive breast cancer 1.

Important Considerations

  • Postmenopausal status: Letrozole is only effective in postmenopausal women, as it works by inhibiting the aromatase enzyme that converts androgens to estrogens in peripheral tissues 1.
  • Hormone receptor-positive status: Letrozole is only effective in women with hormone receptor-positive breast cancer, as it works by reducing estrogen levels in the body 1.
  • Side effects: Letrozole can cause side effects such as hot flashes, night sweats, vaginal dryness, musculoskeletal symptoms, osteoporosis, and increased risk of bone fracture 1.

From the FDA Drug Label

1 INDICATIONS AND USAGE

1.1 Adjuvant Treatment of Early Breast Cancer Letrozole Tablets, USP are indicated for the adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer. 1.2 Extended Adjuvant Treatment of Early Breast Cancer Letrozole Tablets, USP are indicated for the extended adjuvant treatment of early breast cancer in postmenopausal women, who have received 5 years of adjuvant tamoxifen therapy 1.3 First and Second-Line Treatment of Advanced Breast Cancer Letrozole Tablets, USP are indicated for first-line treatment of postmenopausal women with hormone receptor positive or unknown, locally advanced or metastatic breast cancer. Letrozole Tablets, USP are also indicated for the treatment of advanced breast cancer in postmenopausal women with disease progression following antiestrogen therapy

The uses of Letrozole (Femara) are:

  • Adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer
  • Extended adjuvant treatment of early breast cancer in postmenopausal women who have received 5 years of adjuvant tamoxifen therapy
  • First-line treatment of postmenopausal women with hormone receptor positive or unknown, locally advanced or metastatic breast cancer
  • Treatment of advanced breast cancer in postmenopausal women with disease progression following antiestrogen therapy 2

From the Research

Uses of Letrozole (Femara)

Letrozole (Femara) is a nonsteroidal inhibitor of aromatase enzyme complex, used in the treatment of postmenopausal women with breast cancer. The uses of Letrozole include:

  • Treatment of advanced breast cancer in postmenopausal women, with hormone receptor positive or unknown breast cancer, who had failed one prior antiestrogen treatment 3
  • First-line treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer 3, 4, 5
  • Extended adjuvant therapy after completion of tamoxifen therapy in postmenopausal women with hormone-responsive early-stage breast cancer 4, 5, 6
  • Neoadjuvant treatment in postmenopausal women with untreated primary breast cancer 5
  • Second-line therapy for advanced breast cancer in postmenopausal women who have disease progression following anti-estrogen therapy 4, 5, 7

Benefits of Letrozole

The benefits of Letrozole include:

  • Superior efficacy compared to tamoxifen in first-line treatment of advanced breast cancer 3, 4, 5
  • Improved disease-free survival in postmenopausal women with hormone-responsive early-stage breast cancer 4, 5, 6
  • Well-tolerated with a similar tolerability profile to tamoxifen 4, 5, 6
  • Cost-effective alternative to tamoxifen as adjuvant therapy in postmenopausal women with hormone receptor-positive early-stage breast cancer 4

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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