A modest abnormality of the blood can lead insidiously to a cancer 30 years after

Health 23 January, 2018


Published the 23.01.2018 to 23h52


Keywords :

gammapathie monoclonaltransformation malignemyélome

The monoclonal gammopathies of undetermined significance (MGUS or MGUS in English) are a mild form of anomaly in the rate of a protein in the blood, an immunoglobulin. This anomaly means an abnormality in the production of antibodies, blood proteins that play a role in the immune defense system, either qualitative or quantitative.
This condition is generally benign, but it may lead to a cancer of the blood, with complications (bleeding, anemia). A new study, published in the New England Journal of Medicine, shows that according to its type, the risk of transformation to cancer of the blood are very different depending on the type of immunoglobulin and the association of risk factors associated with it.

The fault is gradually moving towards the disease

The researchers followed 1384 persons with monoclonal gammopathy of undetermined significance diagnosed between the years 1960 and 1994, and residing in the State of Minnesota, in the United States. The follow-up of these people is spread over a period of 34 years on average.
The researchers are particularly focused on the transformation of the gammapathie monoclonal in a cancer of the blood (a blood disease) : a multiple myeloma or a disorder of cell widgets or lymphoid.

The presence of risk factors

The risk of transformation to cancer of the blood, the monoclonal gammopathy is of 10% at 10 years, 18% at 20 years, 28% at age 30, 36% at age 35 and 36% in 40 years. But depending on the type of gammapathie monoclonal, the risk is not the same. The risk is higher if it is an immunoglobulin of the type IgM only if this is not an IgM (IgG or IgA) and the risk is modulated as a function of the existence of risk factors (ratio of channels of light in the blood and rate of immunoglobulin)
In the end, the life expectancy is reduced in the case of gammapathie monoclonal of undetermined significance compared to the normal population (8,1 versus 12.4 years in average), but the risk of transformation to cancer at 20 years old is very different depending on the type of gammapathie monoclonal of 7% in the case of gammapathie non-IgM without risk factor at 55% in the case of gammapathie IgM with 2 risk factors.