Stanford Medicine breast surgeons are the first in the US to use a new technology that lights up cancer cells left behind when a tumour is removed.
Surgeons can use a fluorescent imaging system to see whether cancer cells remain after a tumour is removed while still in the operating room. If so, they can remove the residual cancer immediately.
The new technology, LumiSystem, was approved by the US Food and Drug Administration in 2024.
Stanford Medicine is the first hospital system to integrate it into its breast cancer treatment programme. Stanford surgeons Irene Wapnir, Kimberly Stone, and Jacqueline Tsai have begun using the system on eligible lumpectomy patients who opt to receive it.
In an interview with Sarah Williams for Stanford Medicine, Irene Wapnir, a senior investigator in a pivotal national trial of this technology, discussed how it works and who benefits from it.
She explained that surgeons aim to remove breast tumours during lumpectomy while preserving healthy tissue completely.
However, determining tumour boundaries is difficult, and traditional pathology examines less than 1% of the tissue surface, which can miss remaining cancer cells.
The new imaging system uses a fluorescent dye that lights up cancer-specific enzymes, allowing real-time visualisation of residual cancer in the surgical cavity.
This technology helps surgeons identify and remove remaining cancer during the initial surgery, reducing the need for follow-up procedures.
In the clinical trial with 357 patients, the system identified cancer in 14.5% of cases that would have otherwise required another surgery.
It also showed strong accuracy when no cancer was present. The process adds only five to seven minutes to the operation and is currently offered to select patients, with hopes to expand its use.
She explained: ‘Patients receive the injection of dye about two hours before surgery. After we remove the tumour, it takes just a few minutes to scan the cavity with the imaging device. If needed, we remove additional “shaves” of tissue. On average, the technology added about five to seven minutes to the operation.
‘We offer it to eligible patients and explain how it works. Most are enthusiastic about it – they’re on board once they hear it might avoid a second surgery. We’re careful to be transparent about its limitations. For now, we offer it only to patients with a single breast lesion who haven’t had previous radiation, chemotherapy or lumpectomy. But we’re starting to look at it in patients with recurrences or post-chemotherapy surgeries. I think this kind of technology is helping surgeons, pathologists, and patients achieve better outcomes.’
