Sentinel node status and tumor characteristics: a study of 234 invasive breast carcinomas.

CONTEXT: Axillary lymph node status is the most important prognostic factor in patients with breast cancer. Tumor size and lymph node status, the most reliable pathologic bases of the tumor staging system, are practical parameters for estimating survival status. With the advent of lymphatic mapping and sentinel node (SN) identification, there is potential for a more efficient and sensitive evaluation of the axillary lymph node status.

OBJECTIVE

To correlate SN status with tumor size, grade, and lymphovascular invasion.

DESIGN

We examined 234 patients with unifocal breast carcinomas measuring 25 mm or less as detected by preoperative ultrasound during the period May 1998 through December 2002. Sentinel nodes were examined by frozen section and paraffin section as per protocol.

RESULTS

Of the 234 patients, SN was identified in 221 (94.5%). An average of 1.38 SNs were examined per patient. Seventy-seven of 221 patients were SN positive on paraffin section. Sixty-six (85.7%) of these 77 cases could be correctly diagnosed as positive for metastatic carcinoma on frozen section. Two cases reported as positive on paraffin section were reported as suspicious on frozen section. Logistic regression indicated that tumor size, grade, and lymphovascular invasion were all significantly associated with SN status (P < .001).

CONCLUSIONS

Tumor size, grade, and lymphovascular invasion were significantly associated with SN status in unifocal invasive breast carcinoma.