Those with a first-degree relative diagnosed with certain blood cancers may be at an increased risk for developing the disease themselves.
Individuals with a parent, sibling or child with blood cancer appear to have a higher likelihood of also being diagnosed with the disease, according to study results published in Blood.
Moreover, age of diagnosis; whether the relative is a parent, sibling or child; and the number of affected first-degree relatives were substantially associated with familial risk for certain blood cancers.
“Although many hematological malignancies are individually rare, collectively they contribute significantly to the overall cancer burden in the population,” the researchers wrote, adding that the etiological basis of most blood cancers is poorly understood.
Therefore, they analyzed data from over 16 million individuals from the Swedish Family-Cancer Database to determine the familial risk of the different blood cancer and their possible inter-relationship.
Those with a familial link to the disease represented 4.1% of all blood cancer diagnoses — higher than patients with cancers of the nervous system, kidney and pancreas. However, this was lower than those with cancers of the breast, colon and prostate, which ranged from 8% to 15%.
In total, the researchers identified 153,115 patients who were diagnosed with a primary blood cancer, including myeloproliferative neoplasms (MPN; polycythemia vera, essential thrombocythemia, myelofibrosis and MPN not otherwise specified), chronic myeloid leukemia, myelodysplastic syndrome, acute myeloid leukemia, acute lymphocytic leukemia, Hodgkin lymphoma, non-Hodgkin lymphoma, diffuse large B cell lymphoma, follicular lymphoma, mantle cell lymphoma, marginal zone lymphoma, Burkitt lymphoma, small lymphocytic lymphoma, hairy cell leukemia, chronic lymphocytic leukemia and multiple myeloma.
The researchers found the highest relative risks for familial risk among patients with certain Hodgkin lymphoma subtypes (lymphoplasmacytic lymphoma and mantle cell lymphoma) and with polycythemia vera, myelodysplasia and essential thrombocythemia.
“This information improves our understanding of the causes of — and potential inherited predisposition to – blood cancers and should inform the identification and characterization of genetic risk factors for blood cancer, as well as how we best clinically manage patients and their relatives,” lead study author Dr. Amit Sud, from The Institute of Cancer Research in London, said in a press release. “The results should also encourage conversations among families, clinicians and patients about familial risk.”
The researchers noted that these results underscore the need for further examination to better understand familial risk and, in turn, develop definitive screening protocols for these individuals and their families.
“We hope these robust data will be used to inform guidelines on genetic testing and screening,” Sud said in the release. “Certainly there are a number of individuals, such as those with a relative diagnosed at a young age and or with more than one affected first-degree relatives, for whom counseling, genetic testing, and surveillance may be appropriate.”