What is the percentage risk of recurrence for a patient with early-stage hormone receptor-positive breast cancer who undergoes lumpectomy (breast-conserving surgery) without adjuvant antihormonal therapy or radiation therapy?

From the Guidelines

The risk of recurrence for a patient with early-stage hormone-positive breast cancer who undergoes only a lumpectomy without antihormonal therapy or radiation is approximately 30-40% over 10 years, although this figure can vary based on individual factors such as tumor size, grade, and patient age. This relatively high recurrence risk is why standard treatment typically includes additional therapies beyond surgery alone. Without radiation therapy after lumpectomy, local recurrence rates (cancer returning in the same breast) increase significantly, as radiation reduces this risk by about two-thirds, as seen in studies where locoregional recurrence rates were 1% in the lumpectomy, radiation, and tamoxifen arm and 4% in the lumpectomy plus tamoxifen arm 1. Similarly, omitting antihormonal therapy (such as tamoxifen or aromatase inhibitors) leaves the patient vulnerable to both local and distant recurrence, as these medications block the growth-stimulating effects of estrogen on remaining cancer cells.

Some key points to consider in managing early-stage hormone-positive breast cancer include:

• The importance of radiation therapy in reducing local recurrence rates, with studies showing a statistically significant reduction in ipsilateral breast tumor recurrence with radiation therapy 1.
• The role of antihormonal therapy in blocking the growth-stimulating effects of estrogen on cancer cells, which is crucial for reducing both local and distant recurrence.
• The variation in recurrence risk based on individual factors including tumor size, grade, lymph node involvement, patient age, and specific biological characteristics of the tumor.
• The recommendation for a complete treatment regimen that typically includes lumpectomy followed by radiation therapy and 5-10 years of appropriate antihormonal therapy, which together can reduce the recurrence risk to approximately 5-15% over 10 years, as supported by guidelines such as those from the NCCN 1.

Given the evidence, it is clear that omitting both radiation and antihormonal therapy significantly increases the risk of recurrence, making it essential to consider these treatments as part of a comprehensive management plan for early-stage hormone-positive breast cancer. The decision to use these treatments should be individualized based on discussion between the patient and her care team, taking into account the patient's specific circumstances and the potential benefits and risks of each treatment option, as recommended by guidelines such as those from the NCCN 1.

From the Research

Recurrence Risk for Early Stage Hormone Positive Breast Cancer

• The provided studies do not directly address the specific scenario of a patient with early stage hormone positive breast cancer who only gets a lumpectomy but does not take antihormonal therapy or radiation.
• However, study 2 reports on patients who received breast-conserving surgery, axillary lymph node dissection, and radiation, with a 10-year risk of locoregional recurrence of 2.5%, and a 10-year risk of distant metastasis of 4.4%.
• Study 3 reports a 5-year probability of breast cancer recurrence or death of 17.2% for node-positive patients with HR-positive, HER2-negative early breast cancer receiving adjuvant endocrine therapy.
• Study 4 reports that the 10-year recurrence risk was < 10% with stage I cancer (any grade) and for stage II (node-negative and node-positive), grade I cancer, among women who received adjuvant hormone therapy.
• Study 5 reports that after a median follow-up of 13.3 years, 341 (13.8%) women had recurrences, including 181 (53.7%) with late recurrence, among women with stage I-IIB estrogen receptor-positive breast cancer.
• Study 6 reports that women mostly receiving aromatase inhibitors (AI) had the best recurrence-free survival, compared to those receiving AI and tamoxifen for a similar duration, and those mostly using tamoxifen, among perimenopausal women with early, estrogen receptor-positive breast cancer who received adjuvant chemotherapy and endocrine treatment.

Factors Influencing Recurrence Risk

• Higher stage and grade were associated with recurrence regardless of timing, whereas progesterone receptor negativity was associated with early but not late recurrence 5.
• Receipt of endocrine therapy was associated with reduced risk of overall recurrence 5.
• Minoritized racial and ethnic groups had higher risk of early but not late recurrence compared to non-Hispanic White women 5.