Análise da proporção 2D:4D em pacientes com carcinoma oral de células escamosas

Abstract

The 2D:4Dproportion(ratiobetween the length of the index finger relative to the length of the ring finger) for more than two decades has been used as a marker of human behavior, psychological characteristics and susceptibility to various diseases, including malignant neoplasms. The difference between the second and the fourth finger of the hands is a reflection of the intrauterine exposure to sexual hormones, especially estrogen and testosterone. In the differentiation of the fingers in the prenatal period also act genes that are important in the development of organs and mutations in these genes are related to oral carcinogenesis. This work, of case-control design, proposed to investigate the associationbetween the 2D:4D ratio and the presence of squamous cell carcinoma, in addition to verifying the existence of a 2D:4D pattern in individuals presenting this condition. Participated in this study 30 individuals affected by oral squamous cell carcinoma, assisted by the oncology clinic of the Dilson Godinho Hospital and the Santa Casa Hospital from Montes Claros, Minas Gerais, Brazil and a control group formed by 30 subjects, clinically normal, paired by gender, age and that presented smokers and ethylic habits similar to the group with the disease.The data collection involved measuring the lengths of the index finger and ring of both hands, using a digital caliper and 2D:4D averages were compared between the two groups. The difference between the right hand ratio in relation to the left hand was also obtained (DR-L). Initially, univariate statistical analyses were conducted in order to describe the frequencies of the general characteristics of samples and the averages of 2D:4D in groups. Then, to compare the averages of the proportion between the groups, the Student's T-test was used for independent samples. All statistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS®) version 19.0 for Windows®, adopting a significance of 5%. Of the 30 individuals in each group, 25 (83%) were men and 05 (17%) women. The 2D:4D means were higher in the group of oral cancer patients compared to the control group, especially for the right hand (0.975 and 0.957, respectively, p=0.07). When compared by gender, men with cancer presented right 2D:4D higher than healthy men (0.980 and 0.959,p=0.04, respectively). This study reinforces the relationship, built upon previous studies, between 2D:4D as a likely biomarker associated with oral squamous cells carcinoma, suggesting that intrauterine exposure to fetal estrogens could be a likely risk factor for this multifactorial disease.