Can the Serum Level of Myostatin be Considered as an Informative Factor for Cachexia Prevention in Patients with Medullary Thyroid Cancer?

Thyroid cancer, the most common endocrine neoplasia, consists of four main types of carcinomas: papillary, follicular, and anaplastic, all with thyroid follicular origin, and medullary thyroid cancer (MTC) related to para-follicular cells. Cronic diseases such as diverse cancers may be associated with cachexia, especially at advanced stage. Cancer-induced cachexia is associated with diminished quality of life, functional performance, reduced response to antitumor therapy, and increased morbidity and mortality. Myostatin (Mst) is one of the outstanding molecules in the skeletal muscle loss process in cancer and it may be released by both skeletal muscle and cachexia-inducing tumors. Recently changes in serum levels of Mst have been identified as an important factor of cancer-induced cachexia. The goal of this study was to assessserum Mst levels in MTC patients. In this descriptive and case-control study, 90 participants were selected, comprising 45 MTC patients (20 males, $29{\pm}13.9years$, 25 females, $29{\pm}14.5years$) and 45 control individuals (25 males, $23.1{\pm}11.6years$, 20 females, $31.5{\pm}14.4years$). Serum Mst was determined using an ELISA kit and body mass index (BMI) was calculated by weight and height measurements. The Kolmogorov Simonov test showed a normal distribution for log transformed Mst serum levels in both case and control groups. Geometric means were 5.9 and 8.2 ng/ml respectively, and a significant difference was found according to the independent t-test results (P<0.01). There was also a significant difference mean of Mst between females in control and MTC groups, but not for the males. Pearson correlation test showed no correlation between age and BMI with Mst serum levels. The findings of this study support the hypothesis that Mst serum levels may have a potential ability for early diagnosis of cachexia in MTC patients, especially in females.