Which of the following is NOT a benign proliferative breast lesion associated with increased risk of cancer?

Ductal carcinoma in situ (DCIS) is classified as a non-invasive form of breast cancer, rather than a benign proliferative lesion. While it is true that DCIS is a precursor to invasive breast cancer and is associated with an increased risk of developing invasive disease, it is fundamentally different from benign lesions that may also raise cancer risk.

In contrast, atypical ductal hyperplasia, lobular carcinoma in situ (LCIS), and atypical lobular hyperplasia are all considered benign proliferative lesions. These conditions indicate abnormal growth of breast cells but do not invade surrounding tissues. They are associated with an increased risk of breast cancer but do not themselves represent cancerous conditions.

Understanding the distinctions among these lesions is crucial for breast cancer screening and management, as the presence of atypical hyperplasia or LCIS may prompt closer surveillance or preventive measures, while the presence of DCIS often requires a more aggressive treatment approach due to its potential to progress to invasive cancer.