Survival outcomes after contralateral prophylactic mastectomy: a decision analysis

Area of Science:

• Oncology
• Surgical Oncology
• Biostatistics

Background:

• Rising rates of contralateral prophylactic mastectomy (CPM) suggest potential overestimation of benefits.
• Evaluating the survival advantage of CPM in unilateral breast cancer is crucial.

Purpose of the Study:

• To quantify the survival benefit of CPM in women diagnosed with unilateral breast cancer.
• To provide realistic expectations regarding the impact of CPM on life expectancy and survival.

Main Methods:

• A Markov model simulated survival outcomes for CPM versus no CPM in early-stage breast cancer patients (Stage I-II) without BRCA mutations.
• Data on contralateral breast cancer (CBC) incidence, mortality, and age-specific mortality were sourced from published literature.
• Life expectancy (LE) gain, 20-year overall survival, and disease-free survival were calculated for patient cohorts stratified by age, estrogen receptor (ER) status, and cancer stage.

Main Results:

• Predicted LE gain from CPM was minimal, ranging from 0.08 to 0.59 years.
• Absolute 20-year survival differences were less than 1% across all analyzed patient groups.
• CPM showed slightly greater benefit in younger patients, Stage I cancer, and ER-negative tumors.

Conclusions:

• The survival benefit of CPM is less than 1% for most women with unilateral breast cancer, irrespective of age, ER status, or stage.
• Decision-analytic models can help establish more accurate patient expectations regarding CPM outcomes.