What are the breast tumor indications for sentinel lymph node biopsy (SLNB)?

Sentinel lymph node biopsy (SLNB) is indicated in specific scenarios related to breast tumors, particularly for those tumors that carry a risk of metastasis and where the need for surgical staging is warranted. The correct choice involves ductal carcinoma in situ (DCIS) with certain characteristics, such as comedo necrosis and a malignant tumor larger than 1 cm.

Invasive ductal carcinoma (IDC) greater than 1 cm or with specific features suggests a higher likelihood of lymphatic spread. Therefore, SLNB is essential for determining whether cancer has spread to the lymph nodes. In cases of DCIS, particularly when there are high-risk features like comedo necrosis, the surgical management typically involves breast-conserving surgery followed by radiotherapy. Still, SLNB can help in identifying any unexpected invasiveness or lymphatic involvement.

In contrast, benign tumors with atypical hyperplasia do not warrant SLNB because they generally do not exhibit lymphatic spread. Similarly, invasive lobular carcinoma under 1 cm may not meet the necessary threshold for SLNB unless there are specific clinical indications due to its tendency to be non-palpable or associated with multifocality but is often managed in a conservative manner when small. Stage III breast cancers typically