Which term describes the development of new cancer sites within the same breast that contraindicates a lumpectomy?

The development of new cancer sites within the same breast is referred to as multifocality. Multifocality indicates that there are multiple tumor foci located close to one another within a single breast. In cases where multifocality exists, these separate sites can complicate the surgical approach, especially with a lumpectomy, which involves removing only the tumor and a margin of surrounding tissue. If multifocal disease is present, a lumpectomy may not be adequate to ensure clear margins around all cancerous areas, thereby increasing the risk of leaving residual disease behind.

In contrast, metastasis refers to cancer spreading from one part of the body to another, typically indicating the disease has advanced significantly beyond the primary site. Recurrence usually implies that cancer has returned after a period of remission at the same site after treatment, which is separate from the idea of multiple simultaneous lesions. Intraductal carcinoma describes a specific type of cancer that originates within the ducts of the breast but does not exclusively signify multiple sites of cancer within the same breast. Thus, the term that accurately conveys the presence of multiple distinct cancer sites within a breast, leading to contraindications for a lumpectomy, is multifocality.