Diagnosis

Atypical hyperplasia is usually discovered after a biopsy to evaluate a suspicious area found during a clinical breast exam or on an imaging test, such as a mammogram or ultrasound.

To further evaluate atypical hyperplasia, your doctor may recommend surgery to remove a larger sample of tissue to look for breast cancer. A diagnosis of atypical hyperplasia may lead to a surgical biopsy (wide local excision or lumpectomy) to remove all of the affected tissue. The pathologist looks at the larger specimen for evidence of in situ or invasive cancer.