These guidelines developed by the National Institute for Health and Care Excellence (NICE)  for England, apply to adults who are referred to secondary care with suspected MM and those with newly diagnosed or relapsed MM (including high‑risk MM and primary plasma cell leukaemia). The guidelines are based on the best available evidence of clinical and cost effectiveness with the aim of helping healthcare professionals and patients to make informed choices. The guidelines include the following uses for sFLC:
The guidelines recommend the use of SPE and sFLC analysis to screen for the presence of a monoclonal protein in people with suspected myeloma. In the case of an abnormal SPE, sIFE should be used to confirm the presence of a monoclonal protein. No single method (SPE, sIFE, sFLC or UPE) should be used alone to exclude a diagnosis of myeloma.
It was also noted that even though evidence indicates that urine BJP testing was almost as effective as sFLCs for diagnosing plasma cell disorders, urine testing was done for only a fraction of patients. “This could have resulted in potential missed diagnoses if the sFLC test was not performed as an alternative”. Therefore, urine testing was not included in the recommendations to screen for a monoclonal protein.
The guidelines recommend that sFLC analysis should be performed at myeloma diagnosis, and the sFLC ratio used to assess prognosis.
Further research into the use of Hevylite as a prognostic marker is recommended.
Monitoring SMM and MM
The guidelines recommend monitoring people with SMM every 3 months for the first 5 years, with the frequency of subsequent follow-ups based on the long-term stability of the patient’s disease. People who have completed myeloma treatment and recovered should be monitored at least every 3 months.
Monitoring for MM and SMM should include serum immunoglobulins and SPE, as well as sFLC analysis, if appropriate, alongside other laboratory tests.