(P112) Single-Institution Experience With Intrabeam IORT for Treatment of Early-Stage Breast Cancer

April 15, 2014
Volume 28, Issue 1S

Preoperative and postoperative patient and tumor characteristics for breast cancer patients treated at New York Presbyterian Hospital, Weill Cornell Medical College with Intrabeam intraoperative radiation therapy (IORT) are reported.

Himanshu Nagar, MD, Ronnie Li, Paul Christos, DrPH, MS, Suchit H. Patel, PhD, Sam Trichter, PhD, Eugene Nowak, MD, Alex Swistel, MD, Dattatreyudu Nori, MD, K.S. Clifford Chao, MD, Michael Smith, MD, John Ng, MD, Mary Katherine Hayes, MD; New York Presbyterian Hospital, Weill Cornell Medical College

Purpose: Report preoperative and postoperative patient and tumor characteristics for breast cancer patients treated at New York Presbyterian Hospital, Weill Cornell Medical College with Intrabeam intraoperative radiation therapy (IORT).

Methods: Records of all 61 patients treated with Intrabeam IORT from 2012–2013 were retrospectively reviewed.

Results: The median follow-up time was 6.0 months (range: 0.0–18.1 mo), and no patients have developed a local recurrence. The average age was 71.1 ± 8.9 years (range: 53–89 yr). Left-sided breast cancer accounted for 50.8% of the patients. The median applicator size was 3.5 cm (range: 3–5 cm). The median tumor size was 1.0 cm (range: 0.1–2.5 cm). The histology of the tumors was 70.5% invasive ductal carcinoma (IDC), 19.7% invasive lobular carcinoma (ILC), and 9.8% ductal carcinoma in situ (DCIS). Only one patient with ILC was under the age of 65 years. With respect to grade, 26.2% of tumors were high-grade, 50.8% of tumors were intermediate-grade, and 23.0% of tumors were low-grade. Node positivity was seen in five patients (8.2%), and lymphovascular invasion was seen in six patients (9.8%), of whom only three patients were not recommended to undergo external beam RT (EBRT). With respect to receptor status, 91.8% were estrogen receptor (ER)-positive, 77.0% were progesterone receptor (PR)-positive, and 3.3% were human epidermal growth factor receptor 2 (HER2)-positive. All patients underwent same-day surgery, and there were no perioperative or postoperative complications.

Conclusion: Patients treated with Intrabeam IORT at our institution were a more favorable group of patients compared with the TARGIT trial, as they were elderly women with small, hormone receptor-positive, and node-negative tumors. Treatment was well tolerated, with high patient satisfaction.