This calculator provides an estimated risk score based on common risk factors. It is not a substitute for professional medical advice.
No
Yes, one relative
Yes, two or more relatives
No
Yes
Your Estimated 5-Year Risk Score:
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Understanding Breast Cancer Risk
Breast cancer is a complex disease, and its risk is influenced by a combination of genetic, lifestyle, and environmental factors. While some risk factors, like age and genetics, cannot be changed, understanding them can empower individuals to make informed decisions about their health and screening.
This calculator uses a simplified model to estimate a woman's risk of developing breast cancer within the next five years. It considers several key factors that are known to be associated with increased risk.
Factors Considered:
Age: The risk of breast cancer increases significantly with age, particularly after 50.
Age at Menarche: Starting menstruation at a younger age (earlier menarche) is associated with a slightly higher risk, likely due to a longer lifetime exposure to estrogen.
Age at First Full-Term Birth: Having a first full-term birth at an older age is associated with a higher risk compared to having a birth at a younger age.
Number of Breast Biopsies with Atypical Hyperplasia: A history of specific benign breast conditions, such as atypical hyperplasia found in a biopsy, significantly increases breast cancer risk.
Family History: Having close relatives (mother, sister, daughter) with breast cancer is a well-established risk factor. The risk is higher with more affected relatives and if they were diagnosed at a younger age.
Hormone Replacement Therapy (HRT): Long-term use of combined estrogen and progestin HRT can increase breast cancer risk.
How the Risk is Calculated (Simplified Model):
This calculator employs a simplified scoring system. Each input is assigned a weight or a multiplier based on its known association with breast cancer risk. These values are then combined to produce a relative risk score.
Note: This is a conceptual representation. Actual clinical risk assessment models (like the Gail Model or Tyrer-Cuzick model) are more complex, often incorporating race/ethnicity, breast density, and specific genetic mutations (like BRCA). This calculator is for educational purposes and does not replicate those sophisticated models.
The calculation logic is as follows:
A base risk is established.
Points are added or multipliers applied based on the input values:
Age: Higher age contributes more to the score.
Age at Menarche: Lower age (e.g., < 12) adds to the score.
Age at First Birth: Higher age (e.g., > 25) adds to the score.
Biopsies: Each biopsy with atypical hyperplasia significantly increases the score.
Family History: More affected relatives increase the score substantially.
HRT: Use of HRT increases the score.
The final score is a relative indicator. A higher score suggests a higher estimated risk compared to the general population or individuals with lower scores.
Interpreting the Results:
The calculated risk score is an estimate. It should be discussed with a healthcare provider who can consider the full clinical picture, including factors not included in this calculator (like breast density, lifestyle, and personal medical history). Your doctor can help you understand what your risk score means for you and recommend appropriate screening and prevention strategies.
Disclaimer: This tool is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.
function calculateRisk() {
var age = parseFloat(document.getElementById("age").value);
var age_menarche = parseFloat(document.getElementById("age_menarche").value);
var age_first_birth = parseFloat(document.getElementById("age_first_birth").value);
var num_biopsies = parseFloat(document.getElementById("num_biopsies").value);
var family_history = parseFloat(document.getElementById("family_history").value);
var hormone_therapy = parseFloat(document.getElementById("hormone_therapy").value);
var riskScore = 0;
var riskCategory = "";
// — Simplified Risk Factor Weighting —
// These are illustrative weights and do not represent a validated clinical model.
// Age Factor (simplified linear increase)
if (age > 40) {
riskScore += (age – 40) * 0.5;
}
// Age at Menarche Factor
if (age_menarche 14) {
riskScore += (age_menarche – 14) * 0.5;
}
// Age at First Birth Factor
if (age_first_birth > 25) {
riskScore += (age_first_birth – 25) * 1.0;
} else if (age_first_birth < 20) {
riskScore += (20 – age_first_birth) * 0.5;
}
// Biopsies Factor
riskScore += num_biopsies * 5.0; // Significant increase per biopsy
// Family History Factor
riskScore += family_history * 3.0; // Add points for family history
// Hormone Therapy Factor
if (hormone_therapy === 1) {
riskScore += 2.5; // Add points for HRT use
}
// — Normalize and Categorize (Illustrative) —
// This is a highly simplified normalization. Real models use complex statistical distributions.
// We'll scale the score to roughly represent a percentage risk.
var normalizedRisk = Math.min(riskScore * 1.5, 25); // Cap illustrative risk at 25% for 5-year period
if (normalizedRisk < 5) {
riskCategory = "Low Risk";
} else if (normalizedRisk < 15) {
riskCategory = "Average Risk";
} else if (normalizedRisk < 25) {
riskCategory = "Moderate Risk";
} else {
riskCategory = "Elevated Risk";
}
// Display the result
document.getElementById("riskScore").innerText = normalizedRisk.toFixed(1) + "%";
document.getElementById("riskCategory").innerText = riskCategory;
}