The RD-100i OSNA system and Metasin test are designed to show whether cancer cells have spread from the breast to lymph nodes in the armpits of people diagnosed with invasive breast cancer. During surgery to remove a breast tumour, they are carried out to help the surgeon decide at the time (rather than having to wait for laboratory results) whether the lymph nodes need to be removed as well. This can avoid the need for a second operation, and also allow treatments such as chemotherapy to be started earlier.

NICE recommends the RD-100i OSNA system as an option for detecting cancer cells in armpit lymph nodes during breast surgery in people with early invasive breast cancer. Although the Metasin test shows promise, NICE does not recommend it for use in routine clinical NHS practice, and recommends that more evidence for the test is needed.

Your responsibility

This guidance represents the view of NICE, arrived at after careful consideration of the evidence available. When exercising their judgement, healthcare professionals are expected to take this guidance fully into account. However, the guidance does not override the individual responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or guardian or carer.

Commissioners and/or providers have a responsibility to implement the guidance, in their local context, in light of their duties to have due regard to the need to eliminate unlawful discrimination, advance equality of opportunity, and foster good relations. Nothing in this guidance should be interpreted in a way that would be inconsistent with compliance with those duties.

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