Beta-2-Microglobulin as a Marker in Patients with Thyroid Cancer


BACKGROUND:Thyroid cancer is consider the most common of the endocrine system malignancies, also itrepresents less than 1% of all tumors in human. Beta-2-microglobulin protein (β2M) is a lowmolecular weight polypeptide (11800 Dalton), it is found on the surface of cells which containsnucleus except red blood cells. It is a small subunit and the light chain of major histocompatibilitycomplex class I ( MHC- 1) also known as human leukocyte antigen (HLA) in human.Aim of study:Detection of the possibility of using Beta-2-Microglobulin protein as a marker for thyroid cancer.METHODS:A total of 49 patients with thyroid cancer, their mean age 37.77±13.84 years ranged (18-76 years)were included in this study and healthy age-matched control group were 32 healthy donors, theirmean age 38.12±12.29 years ranged (19- 69 years) collected from healthy volunteers. Serumcreatinine level was determined by automated clinical chemistry analyzer. In addition to Beta-2-Microglobulin protein was determined by Enzyme-linked Immunosorbent Assay technique.RESULTS:The results of serum creatinine level showed a normal level of serum creatinine for all subjects(healthy control and patients) except 14 patients with thyroid cancer who had a level of serumcreatinine out of normal range were excluded. Also the results showed significant increase (p=0.0000001) in mean value of serum β2M protein in patients with thyroid cancer (group B)compared to healthy control (group A). Also the results showed no significant correlation betweenβ2M protein and age (r= 0.153 , p-value 0.379). Also no significant correlation between β2Mprotein and BMI (r= -0.092, p-value 0.598). Moreover, receiver operating characteristics ROCshowed β2M level excellent predictor in the diagnosis of thyroid cancer (area under the curveAUC= 0.970 p<0.001).CONCLUSION:A level of serum β2M is elevated in thyroid cancer and can be used as a marker for thyroid cancerand an assistant in the diagnosis of this disease.