Thyroid Cancer Breakthroughs: How New Imaging and Targeted Drugs Are Changing Treatment

Thyroid cancer is one of the fastest-growing cancers worldwide, and researchers at major medical centers are now testing innovative treatments that could dramatically improve outcomes for patients with aggressive or treatment-resistant forms of the disease. New clinical trials underway at UCSF and UCSD are evaluating cutting-edge imaging technology and targeted medications designed to make tumors more responsive to radioactive iodine therapy, while also studying the molecular mechanisms that drive cancer growth.

What's Driving the Need for New Thyroid Cancer Treatments?

Traditional thyroid cancer treatment has relied on surgery followed by radioactive iodine ablation, a combination that has been effective for decades. However, this approach has significant limitations. Less than one-quarter of patients with lung metastases (cancer that has spread to the lungs) achieve a complete response to radioactive iodine therapy, and the treatment carries risks including pulmonary fibrosis and secondary malignancies. Additionally, aggressive subtypes like anaplastic carcinoma and radioactive iodine-refractory differentiated thyroid carcinoma currently have no truly effective treatments.

This gap in treatment options has spurred researchers to investigate how cancer cells manipulate their internal biology to resist therapy. Recent research reveals that thyroid cancer cells undergo a process called metabolic reprogramming, where they fundamentally rewire how they use glucose, fats, and amino acids to fuel growth and evade treatment. Understanding this mechanism is opening doors to entirely new therapeutic approaches.

How Are Researchers Improving Thyroid Cancer Detection and Treatment?

Medical centers are pursuing several promising strategies to overcome treatment resistance:

• Advanced Imaging with Iodine-124 PET/CT: UCSF is evaluating a new imaging technique using Iodine-124 (I-124), a radioactive isotope that emits positrons and can be visualized with positron emission tomography (PET) scanning. This approach offers superior detection of metastatic thyroid cancer compared to traditional Iodine-123 and Iodine-131 imaging that has been used for decades.
• Targeted Drugs to Enhance Radioactive Iodine Uptake: Researchers are testing medications like larotrectinib that work by blocking specific genetic drivers of thyroid cancer, making tumor cells "hungry" for radioactive iodine and more responsive to this established therapy. This combination approach addresses a fundamental problem: even when tumors shrink from targeted drugs, they often lose their ability to absorb radioactive iodine.
• Gene-Specific Therapies: Clinical trials are evaluating drugs targeting specific genetic mutations found in thyroid cancer, including RET gene fusions (treated with selpercatinib), NTRK gene fusions (treated with entrectinib), and RAS mutations (treated with naporafenib combined with trametinib).

Understanding the Molecular Basis of Treatment Resistance

A major breakthrough in thyroid cancer research involves understanding how DNA methylation and metabolic reprogramming work together to fuel cancer growth and resistance. DNA methylation is an epigenetic process where chemical tags are added to genes, essentially silencing them without changing the underlying DNA sequence. Researchers have discovered that this process and metabolic reprogramming are not independent events but rather create a "mutually reinforcing network" that drives tumor progression.

This bidirectional relationship works like this: metabolic reprogramming influences which genes get methylated by controlling the availability of key metabolites such as S-adenosylmethionine (SAM) and alpha-ketoglutarate (α-KG). Conversely, DNA methylation directly silences genes involved in metabolism and thyroid function, including genes like FASN (involved in fat synthesis) and GLS (involved in amino acid metabolism), as well as NIS, a critical marker of thyroid differentiation. This creates a self-reinforcing cycle where cancer cells become increasingly aggressive and resistant to treatment.

What Treatment Approaches Are Being Tested?

The emerging understanding of the DNA methylation-metabolism axis is driving development of multimodal therapy approaches. Rather than targeting a single pathway, researchers are designing combination treatments that simultaneously address epigenetic changes, metabolic reprogramming, and immune suppression. These approaches may incorporate biomimetic delivery technologies—systems designed to mimic how the body naturally transports molecules—combined with epigenetic therapies, metabolic inhibitors, and immunotherapies.

Currently, 14 thyroid cancer clinical trials are active at UCSF with 4 open to eligible patients, while UCSD has 6 trials in progress. These trials represent a significant shift in how researchers approach thyroid cancer: instead of relying solely on surgery and radioactive iodine, modern treatment increasingly involves genetic testing to identify specific mutations, followed by targeted medications designed to attack those particular vulnerabilities.

Steps to Take If You Have Thyroid Cancer or Are at Risk

• Genetic Testing: Ask your thyroid cancer specialist whether genetic testing of your tumor is recommended. Identifying specific mutations like RET, NTRK, or RAS can determine whether you're eligible for targeted therapies that may be more effective than traditional approaches.
• Clinical Trial Eligibility: Discuss with your oncologist whether you might qualify for clinical trials testing new imaging techniques or targeted medications. Many trials are actively enrolling patients, and participation may provide access to cutting-edge treatments before they become widely available.
• Multidisciplinary Care: Seek treatment at medical centers with active thyroid cancer research programs, such as UCSF or UCSD, where specialists stay current with the latest advances and can offer comprehensive, evidence-based care combining surgery, nuclear medicine, and targeted therapies.

The landscape of thyroid cancer treatment is evolving rapidly. While traditional surgery and radioactive iodine remain important tools, the emergence of targeted therapies, advanced imaging, and a deeper understanding of cancer biology offer new hope—particularly for patients with aggressive or treatment-resistant disease. If you or a loved one has been diagnosed with thyroid cancer, discussing these newer options with your care team could open doors to more personalized and potentially more effective treatment strategies.