[Monoclonal gammopathies of undetermined significance do not systematically require a specialized consultation]

Monoclonal gammopathy of undetermined significance (MGUS) is a frequent entity in the general population. The incidence rate of fortuitous discovery of a monoclonal component in asymptomatic patients is increasing nowadays. The majority of MGUS is being addressed to a hematologist for diagnosis or follow-up by their generalist practitioners. The management of MGUS consists of a clinical and biological surveillance as per published and validated international guidelines available for MGUS diagnosis and follow-up. MGUS thus may not necessarily need a specialized consultation and follow-up in a hematology ward, as we believe it could be performed by generalist practitioners.

We studied 190 patients addressed to our hematology department of Lille for diagnosis or follow-up of MGUS.

Among the patients, 9.5% developed a malignant hemopathy (multiple myeloma or Waldenström macroglobulinemia). Among patients diagnosed with MGUS of IgG isotype and a monoclonal component <15 g/L, 96.2% showed no pejorative outcome: these represent simple and routine prognostic factors that can be assessed at diagnosis in order to predict the risk of progression. Those patients could have easily been followed by their generalist practitioner from the diagnosis of MGUS.

A specialist's consultation would still be recommended for patients with pejorative factors at diagnosis, or if a clinical or biological event that could suggest progression occurs during follow-up, or in case of MGUS with complication, in which cases patients would need a specialized management in a hematology department.