Taiwan pioneers non-invasive urine test for thyroid cancer

Taipei, July 31 (CNA) A novel non-invasive method for postoperative monitoring of thyroid cancer using a protein biomarker in urine has the potential to cut detection costs, according to researchers in Taiwan.

Thyroid cancer is the ninth most common cancer among Taiwanese people, according to Wang Chih-yuan (王治元), deputy director at the Department of Internal Medicine at National Taiwan University Hospital and leader of the research team that conducted the groundbreaking study.

"Thyroid cancer has the longest survival rate among thyroid-related cancers, making long-term monitoring an important issue," Wang said at a press conference on Wednesday.

A total thyroidectomy (surgical removal of all the thyroid gland) and radioactive iodine therapy are the two most common treatments for thyroid cancer, explained Wang, adding that the detection of serum thyroglobulin, a protein found in human blood, is the traditional way to monitor patients for residual tumor cells or recurrent cancer.

However, such a detection method is invasive since it requires drawing blood from patients, and can also be affected by anti-thyroglobulin antibodies, Wang noted.

He added that the process also requires the stimulation of recombinant human thyroid-stimulating hormone (rhTSH) to enhance sensitivity, which costs around NT$40,000 (US$1,219) each time.

"Therefore, finding a simple, effective, and non-invasive tracking method (for the patients' conditions) is what we are currently striving to achieve," Wang said.

Dating back to the first batch of 21 patients that joined the study in 2016, the research team found that proteins and peptides in patients' urine, specifically urinary exosomal thyroglobulin (U-Ex Tg) and its associated urinary exosomal peptides panel, can serve as biomarkers that can indicate the recurrence of thyroid cancer.

During the research process, the team collected and analyzed urine samples from patients who had been recently diagnosed with papillary or follicular thyroid cancer before and immediately after a total thyroidectomy, as well as three and six months after surgery.

"The analysis results show a positive correlation between U-Ex Tg levels and tumor size, and provided pathological insights that the traditional method (of serum thyroglobulin detection) cannot achieve," Wang said, noting the new method also has higher sensitivity and accuracy than the traditional one.

To validate the trend changes in the levels of U-Ex Tg, the research team also analyzed galectin-3/TIMP/Angiopoietin-1, another thyroid cancer-related protein in urine.

Wang said that this research approach is why the detection method has obtained patents in Taiwan, Japan, and the United States, as it involves not just a single protein, "but is validated through additional methods."

Following the International Journal of Nanomedicine publishing his research in May this year, Wang said that his team plans to conduct large-scale clinical trials to further understand the effectiveness of detecting the biomarker U-Ex Tg in patients with different types and stages of thyroid cancer.

"We believe that with the accumulation of more clinical data, U-Ex Tg and its associated urinary exosomal peptides panel will become the standard monitoring method for postoperative thyroid cancer in the future," he added.

According to the most recent published data from Health Promotion Administration, the incidence rate of thyroid cancer in Taiwan in 2021 was 4,626 cases per 100,000 people.