AT ASBS 2017

LAS VEGAS (FRONTLINE MEDICAL NEWS) – Radiation oncologists at the University of Texas MD Anderson Cancer Center, Houston, were able to complete 98% of their radiotherapy plans when women received temporary tissue expanders, instead of immediate reconstructions, at the time of skin-sparing mastectomy, in a series of 384 women, most with stage 2-3 breast cancer.

The expanders – saline-filled bags commonly used in plastic surgery to create new skin – were kept in place but deflated for radiotherapy, which allowed for optimal access to treatment fields; the final reconstruction, successful in 90% of women, came a median of 7 months following radiation.

MD Anderson started offering the approach after the realization that more than 50% of radiation plans were compromised when breasts were reconstructed beforehand, at the time of mastectomy ( Int J Radiat Oncol Biol Phys. 2006 Sep 1;66[1]:76-82 ).

“The shape and volume of the reconstruction” – and the need to avoid damaging the new breast – “got in the way of putting radiation where we wanted it to be. We ended up having bad radiotherapy plans, patients not getting skin-sparing mastectomies, and high probabilities of radiation complications to the reconstruction,” said investigator Eric Strom, MD, professor of radiation oncology at MD Anderson.

Radiologists and plastic and oncologic surgeons collaborated to try tissue expanders instead. “We wanted the advantage of skin-sparing mastectomy without the disadvantages” of immediate reconstruction, Dr. Strom said at the American Society of Breast Surgeons annual meeting.

With the new approach, “radiotherapy is superior. We don’t have to compromise our plans. I can put radiation everywhere it needs to be, without frying the heart” and almost completely avoiding the lungs, he said.

The 5-year rates of locoregional control, disease-free survival, and overall survival were 99.2%, 86.1%, and 92.4%, respectively, which “is extraordinary” in patients with stage 2-3 breast cancer, and likely due at least in part to optimal radiotherapy, he said.

Tissue expanders also keep the skin envelope open so it’s able to receive a graft at final reconstruction; abdominal skin doesn’t have to brought up to recreate the breast.

“This approach lessens negative interactions between breast reconstruction and [radiotherapy] and offers patients what they most desire: a high probability of freedom from cancer and optimal final aesthetic outcome,” said Zeina Ayoub, MD, a radiation oncology fellow at Anderson who presented the findings.

The median age of the women was 44 years, and almost all were node positive. Radiation was delivered to the chest wall and regional lymphatics, including the internal mammary chain.

Fifty women (13.0%) required explantation after radiation but before reconstruction, most commonly because of cellulitis; even so, more than half went on to final reconstruction.

Abdominal autologous reconstruction was the most common type, followed by latissimus dorsi–based reconstruction, and exchange of the tissue expander with an implant.

Dr. Ayoub and Dr. Strom had no relevant disclosures.