Contrast-enhanced spectral mammography for breast cancer

Level of innovation

Three experts considered the technology to be well established in practice and no longer new; 2 experts believed contrast-enhanced spectral mammography (CESM) to be already available in at least 10 UK centres. Three experts considered the technology to be a minor variation on an existing procedure, which is unlikely to alter the procedure safety and efficacy.

Potential patient impact

Three experts said that CESM could support quicker diagnosis or earlier treatment, and 3 experts mentioned existing long waiting times for MRI. One expert said that CESM is more sensitive than standard mammography, and 1 expert said that CESM is more accurate than standard mammography, and could guide more accurate surgical planning. Two clinical experts said that CESM could help to improve detection of certain types of breast cancer (lobular breast cancer and multifocal disease). Four clinical experts stated particular benefits in people with dense breast tissue. One expert noted that CESM could be offered to women aged over 40 with a symptomatic, clinically classified cancer, or women aged under 40 with a potentially malignant abnormality detected by ultrasound. Three clinical experts and both patient groups noted that these technologies may be used in people who are contraindicated for MRI (for example, because of a pacemaker or metal implant) or are unable to have MRI because of claustrophobia. One of the patient groups noted CESM could be used when MRI is contraindicated in patients with a high body mass index (BMI) or certain body habitus.

Three experts commented on the patient experience of CESM compared with MRI, with 1 saying CESM is more tolerable, 1 saying CESM has greater patient acceptability, and 2 saying CESM is a more pleasant experience. Three experts said CESM could reduce hospital visits, by avoiding a separate visit for MRI. One expert added that CESM images are easier to explain to people than MRI images.

Potential system impact

Four experts thought that the technology had the potential to replace MRI or reduce its use, with 3 experts commenting that clinical indications for CESM and MRI are similar. Three experts thought that it would be used in addition to standard care, and 1 considered it a significant variation from the current standard of care. One expert said the technology would be unlikely to replace standard mammography or digital breast tomosynthesis (DBT). Three experts said that CESM is also quicker than MRI, with 1 expert estimating the times to be approximately 25 minutes for CESM, compared with 45 minutes for MRI. One expert said that CESM would improve the workflow and shorten the diagnostic pathway. Two experts also said that MRI can produce false-positive results, which can lead to extra unnecessary visits, investigations and biopsies. One expert mentioned CESM-guided biopsy is now commercially available, and may further reduce MRI waiting times. Two experts thought that using CESM could speed up the patient journey along the diagnostic pathway with potentially fewer clinic visits, because of fewer false-positive results when compared with MRI.

General comments

Three experts said that the CESM technology would be used in addition to standard care. The other 3 experts thought that CESM has the potential to replace breast MRI scanning. One expert cited a lack of good quality comparative evidence from the UK to support the accuracy and efficacy of CESM. They noted concerns around lack of long-term follow up for surgical treatment planning and overtreatment based on CESM result. One expert also mentioned accuracy, lesion size, extent and multi-focality assessment, and post-operative and long-term outcomes in terms of extent and recurrence.

One clinical expert estimated that their centre did approximately 150 CESM examinations per year when used in a symptomatic setting. Another estimated that the same number of patients would need CESM as currently have MRI, which was 150 per year in their hospital. Two experts also suggested that CESM exams would replace MRI pending additional evaluation; 1 expert suggested that CESM could replace MRI, and estimated between 6,000 and 10,000 CESM exams across the UK each year. One expert estimated that between 10,000 and 20,000 people across the UK would be eligible for CESM, if used in selected breast cancer patients. One clinical expert stated that people eligible for dynamic contrast-enhanced MRI would also be eligible for CESM, however reported that the number of patients would vary depending on the individual breast unit.

All 6 experts noted the additional staff training needed to handle contrast agents, cannulate patients or use a powered injection pump. One referred to a learning curve, but noted that staff can adapt quickly. All 6 experts highlighted a risk of adverse events, including allergic reaction to the contrast agent. Five experts commented on the increased radiation dose, with 1 stating it is similar to that delivered by DBT. Two experts mentioned the risk of kidney injury in people with impaired renal function. One expert stated that availability of contrast and consumables, maintenance on machines, and delays from waiting for kidney function test results in those at risk of kidney damage from the contrast injection, may present as practical issues when implementing CESM in the NHS. One expert stated that cost may be a barrier to implementation.