Detection of Molecular Alterations in Medullary Thyroid Carcinoma Using Next-Generation Sequencing: an Institutional Experience

Holomics and Artificial Intelligence-Driven Precision Oncology for Medullary Thyroid Carcinoma: Addressing Challenges of a Rare and Aggressive Disease

Background/Objective: Medullary thyroid carcinoma (MTC) is a rare yet aggressive form of thyroid cancer comprising a disproportionate share of thyroid cancer-related mortalities, despite its low prevalence. MTC differs from other differentiated thyroid malignancies due to its heterogeneous nature, presenting complexities in both hereditary and sporadic cases. Traditional management guidelines, which are designed primarily for papillary thyroid carcinoma (PTC), fall short in providing the individualized care required for patients with MTC. In recent years, the sheer volume of data generated from clinical evaluations, radiological imaging, pathological assessments, genetic mutations, and immunological profiles has made it humanly impossible for clinicians to simultaneously analyze and integrate these diverse data streams effectively. This data deluge necessitates the adoption of advanced technologies to assist in decision-making processes. Holomics, which is an integrated approach that combines various omics technologies, along with artificial intelligence (AI), emerges as a powerful solution to address these challenges. Methods: This article reviews how AI-driven precision oncology can enhance the diagnostic workup, staging, risk stratification, management, and follow-up care of patients with MTC by processing vast amounts of complex data quickly and accurately. Articles published in English language and indexed in Pubmed were searched. Results: AI algorithms can identify patterns and correlations that may not be apparent to human clinicians, thereby improving the precision of personalized treatment plans. Moreover, the implementation of AI in the management of MTC enables the collation and synthesis of clinical experiences from across the globe, facilitating a more comprehensive understanding of the disease and its treatment outcomes. Conclusions: The integration of holomics and AI in the management of patients with MTC represents a significant advancement in precision oncology. This innovative approach not only addresses the complexities of a rare and aggressive disease but also paves the way for global collaboration and equitable healthcare solutions, ultimately transforming the landscape of treatment and care of patients with MTC. By leveraging AI and holomics, we can strive toward making personalized healthcare accessible to every individual, regardless of their economic status, thereby improving overall survival rates and quality of life for MTC patients worldwide. This global approach aligns with the United Nations Sustainable Development Goal 3, which aims to ensure healthy lives and promote well-being at all ages.

Unveiling new chapters in medullary thyroid carcinoma therapy: advances in molecular genetics and targeted treatment strategies

Medullary Thyroid Carcinoma (MTC), a neuroendocrine malignancy that arises from the calcitonin-secreting parafollicular C-cells of the thyroid, constitutes a minor yet impactful fraction of thyroid malignancies. Distinguished by its propensity for aggressive growth and a pronounced tendency for metastasis, MTC poses formidable obstacles to the early diagnosis and therapeutic intervention. The molecular genetics of MTC, particularly the role of the RET gene and the RAS gene family, have been extensively studied, offering insights into the pathogenesis of the disease and revealing potential therapeutic targets. This comprehensive review synthesizes the latest advancements in the molecular genetics of MTC, the evolution of precision therapies, and the identification of novel biomarkers. We also discuss the implications of these findings for clinical practice and the future direction of MTC research.

Pre- and Post-operative Circulating Tumoral DNA in Patients With Medullary Thyroid Carcinoma

CONTEXT

Measurement of driver mutations in circulating tumoral DNA (ctDNA) obtained by liquid biopsy has been shown to be a sensitive biomarker in several human tumors.

OBJECTIVE

The aim of this study was to evaluate the clinical relevance of pre- and post-operative ctDNA in sporadic medullary thyroid cancer (sMTC).

METHODS

We studied pre- and post-operative ctDNA in 26 and 23 sMTC patients, respectively. ctDNA results were correlated to serum calcitonin (Ct), carcinoembryonic antigen (CEA), and other clinical/pathological features.

RESULTS

Twenty-six of 29 (89.7%) sMTCs were mutated either for RET or RAS and 3/29 (10.3%) were negative. Four of 26 (15.4%) cases showed positive pre-operative ctDNA with a significantly higher presence of RET M918T mutation (P = 0.0468). Patients with positive pre-operative ctDNA showed a higher variation allele frequency value of the somatic driver mutation (P = 0.0434) and a higher frequency of persistent disease (P = 0.0221). Post-operative ctDNA was positive only in 3/23 (13%) sMTCs and no one was positive for pre-operative ctDNA. Higher values of both Ct (P = 0.0307) and CEA (P = 0.0013) were found in positive ctDNA cases. Finally, the 7 cases harboring either pre- or post-operative positive ctDNA had a persistent disease (P = 0.0005) showing a higher post-operative serum Ct when compared with cases with negative ctDNA (P = 0.0092).

CONCLUSIONS

Pre-operative ctDNA in medullary thyroid cancer is not useful for diagnostic purposes, but it can be useful for predicting the outcome of the disease. In our series, post-operative ctDNA showed a potential for monitoring the response to therapies, but further studies are required to confirm our results.

Somatic RET Indels in Sporadic Medullary Thyroid Cancer: Prevalence and Response to Selpercatinib

CONTEXT

Although the majority of RET alterations are single nucleotide variants (SNV), small deletions and/or insertions have been reported at variable prevalence. No information about the efficacy of RET-specific inhibitors in patients harboring RET indels has been provided.

OBJECTIVE

We present an update on the prevalence of RET indels in medullary thyroid cancer (MTC) and describe the efficacy of selpercatinib in patients with advanced MTC with RET indels.

METHODS

The MTC tissues of 287 patients were analyzed using an Ion S5 targeted sequencing. The functional role of the reported indels have been evaluated by MutationTaster. Clinical and pathological data of MTC patients harboring a RET indel were collected and analyzed. Two patients with a RET indel were treated with selpercatinib.

RESULTS

Among 178 RET-positive cases, 147 (82.6%) harbored a SNV and 31 (17.4%) a RET in-frame indel. Nine indels were not previously reported and were found to be disease causing by MutationTaster. Patients harboring an indel were found to have an aggressive disease and 2 of them were treated with selpercatinib, experiencing a good response to the treatment.

CONCLUSION

These data show that RET indels are not infrequent and correlate with an aggressive disease. Two RET indel-positive patients showed a partial response to the treatment with a highly selective RET inhibitor; thus, these RET indels can be considered actionable mutations. In order to not miss these alterations, the analysis of the full gene is recommended.

Distribution of RET proto-oncogene variants in children with appendicitis

Background

In addition to patient‐related systemic factors directing the immune response, the pathomechanisms of appendicitis (AP) might also include insufficient drainage leading to inflammation caused by decreased peristalsis. Genetic predisposition accounts for 30%–50% of AP. M. Hirschsprung (HSCR), also characterized by disturbed peristalsis, is associated with variants in the RET proto‐oncogene. We thus hypothesized that RET variants contribute to the etiology of AP.

Methods

DNA from paraffin‐embedded appendices and clinical data of 264 children were analyzed for the RET c.135A>G variant (rs1800858, NC_000010.11:g.43100520A>G). In 46 patients with gangrenous or perforated AP (GAP), peripheral blood DNA was used for RET sequencing.

Results

Germline mutations were found in 13% of GAP, whereas no RET mutations were found in controls besides the benign variant p.Tyr791Phe (NC_000010.11:g.43118460A>T). In GAP, the polymorphic G‐allele in rs2435352 (NC_000010.11:g.43105241A>G) in intron 4 was underrepresented (p = 0.0317).

Conclusion

Our results suggest an impact of the RET proto‐oncogene in the etiology of AP. Mutations were similar to patients with HSCR but no clinical features of HSCR were observed. The pathological phenotypes in both populations might thus represent a multigenic etiology including RET germline mutations with phenotypic heterogeneity and incomplete penetrance.

MicroRNAs in Medullary Thyroid Carcinoma: A State of the Art Review of the Regulatory Mechanisms and Future Perspectives

Medullary thyroid carcinoma (MTC) is a rare malignant neoplasia with a variable clinical course, with complete remission often difficult to achieve. Genetic alterations lead to fundamental changes not only in hereditary MTC but also in the sporadic form, with close correlations between mutational status and prognosis. In recent years, microRNAs (miRNAs) have become highly relevant as crucial players in MTC etiology. Current research has focused on their roles in disease carcinogenesis and development, but recent studies have expounded their potential as biomarkers and response predictors to novel biological drugs for advanced MTC. One such element which requires greater investigation is their mechanism of action and the molecular pathways involved in the regulation of gene expression. A more thorough understanding of these mechanisms will help realize the promising potential of miRNAs for MTC therapy and management.

RET mutated C-cells proliferate more rapidly than non-mutated neoplastic cells

A statistically significant higher prevalence of the RET p.Met918Thr somatic mutation, identified by direct sequencing, was previously reported in MTC > 2 cm than in smaller tumors. Aim of this study was to correlate the full RET and RAS mutation profile, identified by a Next Generation Sequencing approach, with the growth rate, proliferation and tumor size of MTC. Data of 149 sporadic MTC patients were correlated with RET mutations and Ki67 positivity. Eighty-one cases had a somatic RET mutation, 40 had a RAS mutation and 28 were negative. A statistically significant higher prevalence of RET mutations was found in MTC > 2 cm. A higher prevalence of RET more aggressive mutations, higher allelic frequencies and, higher percentage of Ki67 positive cells were found in larger tumors which had also a worse outcome. Our study highlights the predominant role of RET somatic mutations in MTC tumorigenesis. We demonstrate that RET mutation prevalence and allelic frequency (AF) are significantly higher in larger tumors. Based on these results, we can conclude that RET mutated C-cells's growth and proliferation are more rapid than those of non-mutated cells and give origin to bigger and more aggressive MTC.

Role of tissue and circulating microRNAs and DNA as biomarkers in medullary thyroid cancer

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor comprising hereditary or sporadic form with frequent mutations in the rearranged during transfection (RET) or RAS genes. Diagnosis is based on the presence of thyroid tumor mass with altered levels of calcitonin (Ctn) and carcinoembryonal antigen (CEA) in the serum and/or in the cytological smears from fine needle aspiration biopsies. Treatment consists of total thyroidectomy, followed by tyrosine kinase inhibitors (TKi) in case of disease persistence. During TKi treatment, Ctn and CEA levels can fluctuate regardless of tumor volume, metastasis or response to therapy. Research for more reliable non-invasive biomarkers in MTC is still underway. In this context, circulating nucleic acids, namely circulating microRNAs (miRNAs) and cell free DNA (cfDNA), have been evaluated by different research groups. Aiming to shed light on whether miRNAs and cfDNA are suitable as MTC biomarkers we searched three different databases, PubMed, Scopus, WOS and reviewed the literature. We classified 83 publications fulfilling our search criteria and summarized the results. We report data on miRNAs and cfDNA that can be evaluated for validation in independent studies and clinical application.

Updates in the advances of sporadic medullary thyroid carcinoma: from the molecules to the clinic

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine malignancy that originates in parafollicular cells. It is well-known that a quarter of MTC are involved in hereditary multiple endocrine neoplasia type 2 syndromes, whereas most MTC are sporadic. Unlike the commonly encountered gastrointestinal or pulmonary neuroendocrine tumors, most sporadic MTCs have distinct genetic alterations featured by somatic changes of either Rearranged during Transfection (RET) or RAS point mutation. The increasing application of next-generation sequencing, whole-exome sequencing, and other molecular detection techniques enables us to understand MTC comprehensively concerning its detailed molecular changes and their clinical correlations. This article reviews the advances in genetic alterations and their prognostic impact in sporadic MTC among different populations and discusses the associated tumor immune microenvironments and the potential role of immunotherapy targeting PD-L1/PD-1 in treating MTC. Furthermore, the current multikinase inhibitor targeting therapy for sporadic MTC has been summarized here and its efficacy and drug toxicity are discussed. Updates in advance of the role of calcitonin/procalcitonin/calcitonin-related polypeptide alpha (CALCA) gene transcripts in diagnosing and handling MTC are also mentioned. The treatment of advanced MTC is still challenging and might require a combination of several modalities.

Current and Future Role of Tyrosine Kinases Inhibition in Thyroid Cancer: From Biology to Therapy

Thyroid cancer represents a heterogenous disease whose incidence has increased in the last decades. Although three main different subtypes have been described, molecular characterization is progressively being included in the diagnostic and therapeutic algorithm of these patients. In fact, thyroid cancer is a landmark in the oncological approach to solid tumors as it harbors key genetic alterations driving tumor progression that have been demonstrated to be potential actionable targets. Within this promising and rapid changing scenario, current efforts are directed to improve tumor characterization for an accurate guidance in the therapeutic management. In this sense, it is strongly recommended to perform tissue genotyping to patients that are going to be considered for systemic therapy in order to select the adequate treatment, according to recent clinical trials data. Overall, the aim of this article is to provide a comprehensive review on the molecular biology of thyroid cancer focusing on the key role of tyrosine kinases. Additionally, from a clinical point of view, we provide a thorough perspective, current and future, in the treatment landscape of this tumor.

Genetic Landscape of Somatic Mutations in a Large Cohort of Sporadic Medullary Thyroid Carcinomas Studied by Next-Generation Targeted Sequencing

Sporadic Medullary Thyroid Carcinoma (sMTC) is a rare but aggressive thyroid tumor. RET and RAS genes are present in about 50%-80% of cases, but most of the remaining cases are still orphan of a genetic driver. We studied the largest series of sMTC by deep sequencing to define the mutational landscape. With this methodology we greatly reduced the number of RET- or RAS-negative cases and we confirmed the central role of RET and RAS mutations. Moreover, we highlighted the bad prognostic role of RET mutations in sMTC and consolidated the favorable prognostic role of RAS mutations. For the first time, we showed that the variant allele frequency represents an additional prognostic marker inside the group of RET-mutated sMTC.

RET S409Y Germline Mutation and Associated Medullary Thyroid Carcinoma

Background: Inherited medullary thyroid carcinoma (MTC) is primarily caused by RET mutations that are commonly localized in exons 5, 8, 10, 11, and 13-16. In this study, we report pedigrees for individuals with MTC that harbor a germline S409Y variant within exon 6 of the RET proto-oncogene. Methods: Targeted sequencing was used to diagnose four apparently sporadic MTC index cases carrying the germline RET S409Y (c.1226 C>A) variant. Subsequently, 27 relatives of these individuals underwent clinical and genetic assessments and/or thyroid surgery. Furthermore, in silico analyses and in vitro assays were performed to predict or verify the potential oncogenic activity of the S409Y variant. Results: Overall, 15 of 31 participants were found to carry the RET S409Y variant. Of these, 6 presented with isolated MTC (mean age 50.2 years; range 41-75 years), of which 3 presented with neck lymph node metastases and 2 presented with distant liver or lung metastases. Among the remaining 9 carriers, 3 (mean age 56 years; range 41-76 years) had elevated serum calcium-stimulated calcitonin (sCtn) or concurrent marginally elevated serum calcitonin (Ctn) levels, whereas the other 6 (mean age 37.5 years; range 14-52 years) exhibited typical Ctn/sCtn levels (p < 0.05). None of the 15 carriers in these 4 families presented clinical evidence of pheochromocytoma, hyperparathyroidism, or Hirschsprung's disease. In silico analyses revealed that S409Y was a "possibly damaging" mutation that could affect the RET protein inter-domain interface. An in vitro assay revealed that the phosphorylation level of RET tyrosine 905 was relatively higher in the RET S409Y mutant than in wild-type (WT) RET. Moreover, transfection of HEK 293 cells with S409Y enhanced the phosphorylation activity of AKT, ERK pathways, and it increased cell proliferation compared with WT RET, but to a lesser degree than that for the RET C618Y and C634Y mutations. Conclusions: This study demonstrates that the novel germline RET S409Y variant is likely pathogenic and is associated with lower penetrance of MTC than that for the C618Y and C634Y mutations. Individuals with S409Y should be managed using a personalized approach, and additionally, "at-risk" family members should be evaluated. Additional studies are needed to elucidate the correlation between the S409Y mutation and multiple endocrine neoplasia type 2-specific tumors.

Retroposed copies of RET gene: a somatically acquired event in medullary thyroid carcinoma

BACKGROUND

Different pathogenic germline mutations in the RET oncogene are identified in MEN 2, a hereditary syndrome characterized by medullary thyroid carcinoma (MTC) and other endocrine tumors. Although genetic predisposition is recognized, not all RET mutation carriers will develop the disease during their lifetime or, likewise, RET mutation carriers belonging to the same family may present clinical heterogeneity. It has been suggested that a single germline mutation might not be sufficient for development of MEN 2-associated tumors and a somatic bi-allelic alteration might be required. Here we investigated the presence of somatic second hit mutation in the RET gene in MTC.

METHODS

We integrated Multiplex Ligation-dependent Probe Amplification (MLPA) and whole exome sequencing (WES) to search for copy number alteration (CNA) in the RET gene in MTC samples and medullary thyroid cell lines (TT and MZ-CR-1). We next found reads spanning exon-exon boundaries on RET, an indicative of retrocopy. We subsequently searched for RET retrocopies in the human reference genome (GRCh37) and in the 1000 Genomes Project data, by looking for reads reporting joined exons in the RET locus or distinct genomic regions. To determine RET retrocopy specificity and recurrence, DNA isolated from sporadic and MEN 2-associated MTC (n = 37), peripheral blood (n = 3) and papillary thyroid carcinomas with RET fusion (n = 10) samples were tested using PCR-sequencing methodology.

RESULTS

Through MLPA we have found evidence of CNA in the RET gene in MTC samples and MTC cell lines. WES analysis reinforced the presence of the CNA and hinted for a retroposed copy of RET not found in the human reference genome and 1.000 Genomes Project. Extended analysis confirmed the presence of a somatic MTC-related retrocopy of RET in both sporadic and hereditary tumors. We further unveiled a recurrent (28%) novel point mutation (p.G548 V) found exclusively in the retrocopy of RET. The mutation was also found in cDNA of mutated samples, suggesting it might be functional.

CONCLUSION

We here report a somatic specific RET retroposed copy in MTC samples and cell lines. Our results support the idea that generation of retrocopies in somatic cells is likely to contribute to MTC genesis and progression.

[Tumors of the thyroid gland. Proposal for the management and study of samples from patients with thyroid neoplasms]

The recent changes in the classification and staging of thyroid tumors have arisen from the need to provide an adequate response to the exponential increase of thyroid cancer, which, however, has not been accompanied by an increase in mortality. These changes pretend to reduce overdiagnoses of malignancy, unnecessary treatment, side effects as well as cost for the health system. To this end, this article reviews recommendations for the management of thyroid surgical pathology samples with emphasis on the new terminology of the WHO classification. The basic criteria for the diagnosis of malignancy in well-differentiated thyroid carcinomas are reviewed and the criteria for NIFTP (non-invasive follicular tumor with papillary-like nuclear features) diagnosis are updated. Recommendations for the elaboration of the pathological report are also included.

GENETICS IN ENDOCRINOLOGY: Genetic diagnosis of endocrine diseases by NGS: novel scenarios and unpredictable results and risks

The technological advancements in genetics produced a profound impact on the research and diagnostics of non-communicable diseases. The availability of next-generation sequencing (NGS) allowed the identification of novel candidate genes but also an in-depth modification of the understanding of the architecture of several endocrine diseases. Several different NGS approaches are available allowing the sequencing of several regions of interest or the whole exome or genome (WGS, WES or targeted NGS), with highly variable costs, potentials and limitations that should be clearly known before designing the experiment. Here, we illustrate the NGS scenario, describe the advantages and limitations of the different protocols and review some of the NGS results obtained in different endocrine conditions. We finally give insights on the terminology and requirements for the implementation of NGS in research and diagnostic labs.

Salvaging the supernatant: next generation cytopathology for solid tumor mutation profiling

With the expanding role of targeted therapy in patients with solid tumors, pathologists face the daunting task of having to maximize limited volume tissue obtained by fine needle aspiration for a variety of molecular tests. While most molecular studies on fine needle aspiration samples have been reported using cellular material, recent studies have shown that a substantial amount of DNA can be retrieved from the supernatant fluid of aspirate needle rinses after cell pelleting for cytospin or cell block preparations. In routine clinical workflow, the supernatant is discarded; however this fluid may provide a complementary source of DNA for tumor mutational profiling. In this study, we evaluated the post-centrifuged supernatant from 25 malignant and 10 benign fine needle aspiration needle rinses. The mean and median DNA yields from the supernatants were 445 ng and 176.4 ng (range, 15.1-2958 ng), respectively. Next generation sequencing using the Ion AmpliSeq Cancer Hotspot Panel v2 detected somatic mutations in all 25 malignant samples. No mutations were detected in any of the benign samples tested. When available, mutations detected in the supernatant fluid were compared to the next generation sequencing analysis performed on a prior or concurrent surgical specimen from the same patient and showed 100% concordance. In a subset of cases (n = 19) mutations in EGFR, KRAS, BRAF, PIK3CA, and NRAS were successfully confirmed by droplet digital PCR, providing an orthogonal platform for mutation analysis. In summary, in this study we show that post centrifuged supernatants from fine needle aspiration needle rinses can provide a robust substrate for expanded mutation profiling by next generation sequencing, as well as hotspot mutation testing by droplet digital PCR. The ability to detect somatic mutations from otherwise discarded supernatant fluids offers the ability to triage and effectively utilize limited volume fine needle aspiration samples when multiple molecular tests are requested, without the need to re-biopsy for additional tissue samples.

Medullary Thyroid Cancer: Clinical Characteristics and New Insights into Therapeutic Strategies Targeting Tyrosine Kinases

Medullary thyroid carcinoma (MTC) is a hyperplasia of thyroid C-cells, accounting for 5-10% of all thyroid cancers. MTCs may appear as sporadic or hereditary forms, and several molecules and signaling pathways have been found to function defectively in MTC cells. Tyrosine kinases are the most well-studied molecules that have abnormal function in these tumor cells. Due to their limited response, chemotherapeutic agents and radiation therapy are not effective in treating patients with advanced metastatic MTC. In the past decade, significant attention has been given to the utilization of multikinase inhibitors as targeted therapeutic agents for treating MTC patients, with the most promising results arising from the study of tyrosine kinase inhibitors, which generally bind to the ATP binding sites of these kinases. Two drugs-vandetanib and cabozantinib-are approved for the treatment of aggressive advanced MTC; however, the potential for toxicities and adverse effects of these agents on patient quality of life need to be considered against any therapeutic gain. According to recent data, it appears that inhibition of only one receptor or molecule in a pathway is not as effective as simultaneous inhibition of different pathways, indicating the need to use combination therapy. The main purpose of this review is to describe the clinical characteristics, molecular mechanisms, and current molecular and targeted therapeutic strategies active in clinical trials for advanced MTC treatment.

RET mutation heterogeneity in primary advanced medullary thyroid cancers and their metastases

Purpose

Medullary Thyroid Cancer (MTC) whose pathogenesis is strictly related to RET proto-oncogene alterations, has been shown to have a heterogenic RET mutation profile in subpopulations of MTC. The aim of our study was to investigate the RET somatic mutation profile in primary MTC and in the corresponding metastatic tissues in a series of advanced metastatic cases.

Results

This study demonstrated that in about 20% of cases a different RET mutation profile can be found when comparing primary tumor and its corresponding metastases. Furthermore in 8% of tumors, RET intratumor heterogeneity was observed We also showed that in some cases an imbalance of RET copy number was present. We confirmed a high prevalence (90%) of RET somatic mutations in advanced tumors.

Materials and Methods

Fifty-six MTC patients (50 somatic and 6 hereditary cases) have been included in the study and a total of 209 specimens have been analysed by direct sequencing. Multiplex ligation-dependent probe amplification (MLPA) has been used to investigate amplification/deletion of RET alleles.

Conclusions

In conclusion, this study showed a genetic intra- and intertumor heterogeneity in MTC, But in only 20% of CASES These results could justify the relatively moderate level of aggressiveness of the disease with respect to more aggressive human tumors that are characterized by a high rate of mutation and heterogeneity.

Advances and controversies in the management of medullary thyroid carcinoma

PURPOSE OF REVIEW

Medullary thyroid carcinoma (MTC) comprises approximately 4% of all malignant thyroid neoplasms. Although the majority of patients have a good prognosis, a subgroup of patients develops progressive disease and requires systemic therapy. Here, we focused on the current MTC therapeutic approaches and discussed the advantages and disadvantages of molecular targeted therapies.

RECENT FINDINGS

Targeted molecular therapies that inhibit RET and other tyrosine kinase receptors involved in angiogenesis have been shown to improve progression-free survival in patients with advanced MTC. Two drugs, vandetanib and cabozantinib, have been approved for the treatment of progressive or symptomatic MTC, and several others have exhibited variable efficacy. No tyrosine kinase inhibitor has been shown to improve survival. Although no definitive recommendation can currently be made, cumulative data indicate that knowledge of the tumor mutational profile may facilitate improvements in targeted therapy for MTC.

SUMMARY

Tyrosine kinase inhibitors are effective therapeutic agents for the treatment of progressive MTC. Nevertheless, it is not clear who will benefit the most from therapy, and the decision regarding when and how to initiate the treatment should be made based on the patient's medical history and tumor behavior. Hopefully, in the near future, molecular profiling of MTC can be used to determine the most effective molecular therapeutic target.