EXPERT ANALYSIS FROM ASBS 2017
LAS VEGAS (FRONTLINE MEDICAL NEWS) – Although mastectomy is the standard of care for tumor recurrence following lumpectomy and whole breast irradiation, a second lumpectomy with partial breast irradiation is a sound alternative under certain circumstances, according to Manjeet Chadha, MD , professor of radiation oncology and director of the department of radiation oncology at Icahn School of Medicine at Mount Sinai, New York.
It depends on whether the new lesion is a true recurrence, or simply another primary tumor. In the absence of a genetic footprint to compare the two, Dr. Chadha and her colleagues use several of what she called “soft criteria” to make the call and counsel women.
True ipsilateral recurrence of an aggressive tumor tends to happen early, and in the same quadrant. However, if breast cancer recurs more than 3 years after treatment of the primary tumor and in a different quadrant, and if the patient is negative for BRCA mutation, and if the new growth is small, localized on MRI, histologically different from the primary tumor, and likely to be resected with clean margins, Dr. Chadha said she is comfortable offering a second lumpectomy and partial breast radiation – usually multicatheter brachytherapy – to women who do not want a mastectomy.
“Second cancer in a previously irradiated breast is not an uncommon clinical entity. Based on patient preference, the option of repeat breast conservation and reirradiation may be offered selectively as an alternative to mastectomy,” followed by systemic therapy, she said at the annual meeting of the American Society of Breast Surgeons.
“I think all of us across the country are discussing presentations like this in tumor boards,” but it’s not always offered as an option. Sometimes, “the mindset of the treating surgeon is ‘oh, this breast has had radiation; I can’t give radiation again.’ Clearly, whole breast reirradiation is not recommended,” but it seems possible based on a growing body of literature to differentiate new primaries with new biology from true recurrences, and to treat them safely with breast conserving surgery and partial irradiation, she said.
The largest series to date of salvage lumpectomy with multicatheter brachytherapy followed 217 women for a median of 3.9 years. Median tumor size was 1.2 cm. The 5-year local control rate – effectively, the mastectomy-free survival – was 94.4%, and the overall survival was 88.7%, which mirrors the success of first-time lumpectomy with whole breast irradiation, and lends support to the notion that some recurrences are, in fact, entirely new disease. The European team reported excellent or good cosmetic results in 85% of women ( Radiother Oncol. 2013 Aug;108[2]:226-31 ).
The series used high-dose radiation. Dr. Chadha said she and her colleagues have had similar success with low-dose multicatheter brachytherapy, with similarly good aesthetic results. To avoid cosmetic impact, however, she noted it’s important to work with radiation oncologists “mindful of the nuances of what’s needed,” including how far to separate the skin from the radiation.
Brachytherapy has the most support in the literature, but external beam therapy is also an option. “Whatever technique you use, the delineation of the target and the geometric coverage of the lumpectomy cavity [must be] complete in all cases,” she said.
Dr. Chadha had no financial conflicts of interest.
