Theranostic Risk Stratification for Thyroid Cancer in the Genomic Paradigm.

Theranostics define diagnostic evaluations directing patient-specific therapeutic decisions. Molecular theranostics involves genomic, transcriptomic, proteomic, metabolomic and finally phenonic definitions thyroid cancer differentiation. It is the functional differentiation that determines the sensitivity and accuracy of RAI imaging as well as the effectiveness of RAI treatment. Total thyroidectomy is performed to empower an anticipated RAI treatment. A preoperative determination of the genomic and transcriptomic profile of the tumor is a strong predictor of response to therapeutic interventions. This article discusses the oncopathophysiologic basis of the theranostic risk stratification approach.

Molecular Profiling of 50 734 Bethesda III-VI Thyroid Nodules by ThyroSeq v3: Implications for Personalized Management.

CONTEXT: Comprehensive genomic analysis of thyroid nodules for multiple classes of molecular alterations detected in a large series of fine needle aspiration (FNA) samples has not been reported. OBJECTIVE: To determine the prevalence of clinically relevant molecular alterations in Bethesda categories III-VI (BCIII-VI) thyroid nodules. METHODS: This retrospective analysis of FNA samples, tested by ThyroSeq v3 using Genomic Classifier and Cancer Risk Classifier at UPMC Molecular and Genomic Pathology laboratory, analyzed the prevalence of diagnostic, prognostic, and targetable genetic alterations in a total of 50 734 BCIII-VI nodules from 48 225 patients. RESULTS: Among 50 734 informative FNA samples, 65.3% were test-negative, 33.9% positive, 0.2% positive for medullary carcinoma, and 0.6% positive for parathyroid. The benign call rate in BCIII-IV nodules was 68%. Among test-positive samples, 73.3% had mutations, 11.3% gene fusions, and 10.8% isolated copy number alterations. Comparing BCIII-IV nodules with BCV-VI nodules revealed a shift from predominantly RAS-like alterations to BRAF V600E-like alterations and fusions involving receptor tyrosine kinases (RTK). Using ThyroSeq Cancer Risk Classifier, a high-risk profile, which typically included TERT or TP53 mutations, was found in 6% of samples, more frequently BCV-VI. RNA-Seq confirmed ThyroSeq detection of novel RTK fusions in 98.9% of cases. CONCLUSION: In this series, 68% of BCIII-IV nodules were classified as negative by ThyroSeq, potentially preventing diagnostic surgery in this subset of patients. Specific genetic alterations were detected in most BCV-VI nodules, with a higher prevalence of BRAF and TERT mutations and targetable gene fusions compared to BCIII-IV nodules, offering prognostic and therapeutic information for patient management.

Birth of the Beta-knife Thyroidectomy: The Radiance of Saul Hertz.

This is the story of how one man's life's work allowed for Iodine-131 (I-131) to become a therapy for hyperthyroidism and thyroid cancer. What is now a standard in our times arose from Saul Hertz's rather challenging and humble beginnings. Thyroid lobectomy and total thyroidectomy were therapeutic mainstays for thyroid disease until Hertz treated his first patient with radioactive iodine (RAI) ablation therapy at Massachusetts General Hospital (MGH) on March 31, 1941. His concepts for using beta particle emission from RAI to ablate thyroid tissue were revolutionary. Hertz's RAI therapy translated to research with thyroid cancer by the mid-1940s. The high-energy beta particles produced cytolethal effects on remnant thyroid tissue left behind by total thyroidectomy, thereby accomplishing completion thyroidectomy in some patients. Progressive surgeons from the Hertz era incorporated RAI into their practice. MGH surgery resident Francis Moore took sabbatical from clinical training to do translational research with RAI and other radioisotopes. Irving Ariel of New York became known as a nuclear surgeon in the wake of Hertz's work. George Crile Jr of Cleveland became an RAI advocate for the surgical community, implementing several paradigm-changing concepts in thyroid disease along the way. Hertz was a visionary who sparked this movement, predicting many of the molecular dilemmas with RAI-tumor avidity that clinical researchers continue to navigate today. This timely history for surgical oncologists and endocrine surgeons traces the development of RAI therapy through the life of Saul Hertz, a biographical window influenced by social stigma, political controversy, and mainstream media.

Radiomicrosphere Dosimetry: Principles and Current State of the Art.

Radiomicrosphere Therapy (RMT) refers to a liver-directed therapeutic modality based on the intrahepatic arterial administration of radiolabeled microspheres. There is a need for standardization of the terminology of RMT. A descriptive identifier should first name the radioisotope, then the chemical formulation of the microsphere, and lastly add the term RMT that indicates the therapeutic modality. At present, clinically available options include |Y-90| |Resin| |RMT|, |Y-90| |Glass| |RMT| and |Ho-166| |PLLA| |RMT|. The latter is available in Europe and is being considered for clearance by the FDA in the United States. Preclinical studies with |Re-188| |PLLA| |RMT| are underway. Dosimetric considerations are strongly tied to both the type of the radioisotope and the chemical composition of the microsphere type. This review will focus on Y-90 resin and glass RMT, the history, dosimetry, clinical use, and controversies.

A Joint Statement from the American Thyroid Association, the European Association of Nuclear Medicine, the European Thyroid Association, the Society of Nuclear Medicine and Molecular Imaging on Current Diagnostic and Theranostic Approaches in the Management of Thyroid Cancer.

Background: The American Thyroid Association (ATA), the European Association of Nuclear Medicine, the European Thyroid Association, and the Society of Nuclear Medicine and Molecular Imaging have established an intersocietal working group to address the current controversies and evolving concepts in thyroid cancer management and therapy. The working group annually identifies topics that may significantly impact clinical practice and publishes expert opinion articles reflecting intersocietal collaboration, consensus, and suggestions for further research to address these important management issues. Summary: In 2019, the intersocietal working group identified the following topics for review and interdisciplinary discussion: (i) perioperative risk stratification, (ii) the role of diagnostic radioactive iodine (RAI) imaging in initial staging, and (iii) indicators of response to RAI therapy. Conclusions: The intersocietal working group agreed that (i) initial patient management decisions should be guided by perioperative risk stratification that should include the eighth edition American Joint Committee on Cancer staging system to predict disease specific mortality, the modified 2009 ATA risk stratification system to estimate structural disease recurrence, with judicious incorporation of molecular theranostics to further refine management recommendations; (ii) diagnostic RAI scanning in ATA intermediate risk patients should be utilized selectively rather than being considered mandatory or not necessary for all patients in this category; and (iii) a consistent semiquantitative reporting system should be used for response evaluations after RAI therapy until a reproducible and clinically practical quantitative system is validated.

A Review of the History of Radioactive Iodine Theranostics: The Origin of Nuclear Ontology

Studies on the first years of radioactive iodine (RAI) use in thyroid diseases have focused on hyperthyroidism. Saul Hertz's success with RAI in thyrotoxicosis fueled a seamless transition to Samuel Seidlin's investigations with RAI in thyroid cancer. These landmark events embody nuclear ontology, a philosophical foundation for the creation and existence of radio-therapeutic principles that continue to influence clinical practices today. Laying this ontological foundation, Dr. Saul Hertz who is the founding director of Massachusetts General Hospital Thyroid Clinic, affiliated with Harvard University created a framework for RAI theranostics with preclinical experiments and clinical cases from 1937 to 1942. The first thyroid cancer treatment with RAI was applied in 1942 by Samuel Seidlin. The sensational effect of the first application was interestingly powerful enough to overshadow scientific data. Seidlin and colleagues assembled a sixteen-patient series showcasing a unique entity: functional thyroid metastases that respond to RAI. Other investigations at the time demonstrated that RAI had little efficacy as a therapeutic agent, mainly because most thyroid tumors do not form colloid, and therefore cannot concentrate RAI. These findings were soon overshadowed by a mainstream article in the October 1949 issue of Life that portrayed RAI as a lifesaving therapy for thyroid cancer. The paradigm was set, and later writings by William H. Beierwaltes and other prominent nuclear medicine physicians established the primary goals and principles of RAI therapy. The developments in theoretical physics and nuclear instrumentation and the scientists who made these developments in the early years contributed greatly to the development of the concept. In the field of nuclear medicine, William H. Beierwaltes has gone down in our history as a clinical researcher with his most important contributions. The classical paradigm that started with him has carried us to today's molecular theranoistic viewpoint. This paper examines controversial topics in the advent of thyroid theranostics, and applies historical significance to current discussions on the role of RAI in thyroid cancer management. Another paradigm shift is on the horizon as thyroidology enters the age of genomics. The molecular theranostic profiles will soon be incorporated into a dynamic clinical decision-making and management algorithm for thyroid surgery and RAI therapy. From now on, nuclear oncology will gain a new ontological identity with molecular pathology and new theranostic expansions.

Complicated Surgical Removal of an Adherent Port-a-Cath After 11 Years of Implantation.

A 65-year-old woman with a medical history significant for anal cancer was referred by her primary care physician for a port-a-cath removal. The port was placed prior to treatment of squamous cell carcinoma of the anus, 11 years prior to this scheduled removal. She received chemotherapy and radiation in accordance with the Nigro protocol, treating the anal cancer to complete resolution. During port removal, a fibrous capsule was dissected and the port was removed from the left upper breast border along with proximal portion of the catheter. Significant difficulty was found in removing the remaining catheter despite sustained traction and guidewire insertion. Fluoroscopy revealed an intravascular adhesion of the catheter tip in the superior vena cava, which could not be freed. In order to prevent vascular injury, the adhesed portion of the distal catheter was left in place with three large surgical clips placed distally. This case highlights the very rare complication of complete vascular adherence of the terminal catheter tip and extended port intracorporeal time as a risk factor for adhesion. This case also highlights the importance of timely permanent central venous catheter removal following completion of its intended regimen.

Rosai-Dorfman Disease and Unusual Local Invasive Presentation.

Rosai-Dorfman disease (RDD) is a rare medical condition with bilateral painless lymphadenopathy. We present the case of a young man diagnosed with a very unique presentation of Rosai-Dorfman disease. A 40-year-old African-American man presented with a firm, non-tender, progressive chest and neck mass appeared three months ago. Imaging of the neck demonstrated an 8.6-cm anterior neck subcutaneous soft tissue mass extending into the anterior mediastinum through the sternum with erosive changes in the sternum and the lesion is abutting the right common carotid artery and innominate vein and surrounds the medial aspect of the clavicles bilaterally. Ultrasound (US)-guided biopsy showed marked polytypic-appearing plasma cell proliferation associated with relatively prominent histiocytes with hemophagocytosis/emperipolesis and focal neutrophils. There were S100+ histiocytes; however, findings were not typical for RDD. As that biopsy was not diagnostic, incisional biopsy with adequate sampling was performed. Surgical pathology demonstrated a very abnormal infiltrate with prominent histiocytes including areas with the features of extranodal RDD. BRAF V600E immunohistochemistry (IHC) was negative. Modified radical neck dissection, proximal sternal resection and superior mediastinal nodal dissection surgery was recommended. However, the patient refused the procedure. Typical manifestations are lymphadenopathy with fever that our patient did not experience. Bone involvement happens in 5-10% of cases. There is not enough data about blood vessel invasion which make our case unique. Treatment plan is still controversial. Clinical monitoring is recommended if the symptoms are tolerable as regression has been reported in many cases (20-50%). Surgery is reserved for patients with vital organ involvement or extra-nodal disease.

A Case of Papillary Thyroid Carcinoma and Kostmann Syndrome: A Genomic Theranostic Approach for Comprehensive Treatment.

BACKGROUND Theranostics is a combined diagnostic and treatment approach to individualized patient care. Kostmann syndrome, or severe congenital neutropenia, is an autosomal recessive disease that affects the production of neutrophils. Papillary thyroid carcinoma (PTC) is the most common type of thyroid malignancy associated with gene alterations, including in the mitogen-activated protein kinase (MAPK) signaling pathway gene. Translocation of the ETS variant 6/neurotrophic receptor tyrosine kinase 3 (ETV6/NTRK3) gene has been implicated in radiation-induced and pediatric forms of thyroid carcinoma but has rarely been described in sporadic PTC. This report is of a case of PTC in a patient with Kostmann syndrome associated with ETV6/NTRK3 gene translocation. CASE REPORT A 32-year-old woman with a history of Kostmann syndrome, acute myeloid leukemia (AML), and chronic graft versus host disease (GVHD) was diagnosed with PTC with cervical lymph node metastases and soft tissue invasion following total thyroidectomy and bilateral modified radical neck dissection. Her postoperative radioactive iodine (RAI) scan confirmed lymph node metastasis. Gene expression studies identified increased expression of iodine-handling genes and ETV6/NTRK3 gene fusion. Because of the bone marrow compromise due to Kostmann syndrome and AML, a careful genomic and molecular analysis was performed to guide therapy. CONCLUSIONS This is the first reported case of the association between PTC, Kostmann syndrome, and ETV6/NTRK3 gene translocation in which multimodality treatment planning was optimized by genomic profiling.

90 Y SPECT/CT quantitative study and comparison of uptake with pretreatment 99 m Tc-MAA SPECT/CT in radiomicrosphere therapy.

INTRODUCTION: Yttrium-90 (90 Y) microsphere post-treatment imaging reflects the true distribution characteristics of microspheres in the tumor and liver compartments. However, due to its decay spectra profile lacking a pronounced photopeak, the bremsstrahlung imaging for 90 Y has inherent limitations. The absorbed dose calculations for 90 Y microspheres radiomicrosphere therapy (RMT) sustain a limitation due to the poor quality of 90 Y imaging. The aim of this study was to develop quantitative methods to improve the post-treatment 90 Y bremsstrahlung single photon emission tomography (SPECT)/computed tomography (CT) image analysis for dosimetric purposes and to perform a quantitative comparison with the 99m Tc-MAA SPECT/CT images, which is used for theranostics purposes for liver and tumor dosimetry. METHODS: Pre and post-treatment SPECT/CT data of patients who underwent RMT for primary or metastatic liver cancer were acquired. A Jasczak phantom with eight spherical inserts of various sizes was used to obtain optimal iteration number for the contrast recovery algorithm for improving 90 Y bremsstrahlung SPECT/CT images. Comparison of uptake on 99m Tc-MAA and 90 Y microsphere SPECT/CT images was assessed using tumor to healthy liver ratios (TLRs). The voxel dosimetry technique was used to estimate absorbed doses. Absorbed doses within the tumor and healthy part of the liver were also investigated for correlation with administered activity. RESULTS: Improvement in CNR and contrast recovery coefficients on patient and phantom 90 Y bremsstrahlung SPECT/CT images respectively were achieved. The 99m Tc-MAA and 90 Y microspheres SPECT/CT images showed significant uptake correlation (r = 0.9, P = 0.05) with mean TLR of 9.4 ± 9.2 and 5.0 ± 2.2, respectively. The correlation between the administered activity and tumor absorbed dose was weak (r = 0.5, P > 0.05), however, healthy liver absorbed dose increased with administered activity (r = 0.8, P = 0.0). CONCLUSIONS: This study demonstrated correlation in mean TLR between 99m Tc-MAA and 90 Y microsphere SPECT/CT.

The Art and Science of Thyroid Surgery in the Age of Genomics: 100 years after Theodor Kocher.

Cancer is a disorder of the genome. The thyroid cancer genome is being decoded. Recent studies have identified a mutation or a genetic alteration in 95% of thyroid cancers. The National Cancer Institute initiated the Cancer Genome Atlas project in 2006 to catalogue genetic mutations associated with cancer, using genome sequencing and bioinformatics. The project has expanded to carry out genomic characterization and sequence analysis of thyroid cancer. The concept of risk stratification based on traditional parameters will soon vacate their role for clear molecular markers of non-invasive/focal, invasive/metastatic and systemic stages/phases of neoplastic disorder. A refined classification scheme based on genomics and its phenotypic expressions will accurately reflect the biologic differences between the different morphologic definitions we use today. Tumor differentiation/de-differentiation, and clinical behavior of an individual cancer will be defined by molecular markers, in addition to standard morpho-pathology. Empiricism in science of medicine and surgery has acquired a new method for testing the appropriate treatment for individual patients; that is molecular pathology, governed by genomics. The technology is present and rapidly evolving. The surgeons will determine the extent of interventions with molecular evidence and guidance.

Radioactive Iodine Remnant Ablation: The Beta-knife Completion Thyroidectomy.

The rationale and objectives for radioactive iodine (RAI) ablation remain perplexing to many. This review addresses the meaning, clinical context and the goals of "ablation": the RAI treatment after a total thyroidectomy. This article also aims to clarify the definition of a total thyroidectomy and how a thyroid remnant can introduce a confounding factor in the postoperative management of patients with differentiated thyroid cancer. The implications of an existing thyroid remnant on RAI diagnostic imaging and serum thyroglobulin levels are discussed. This review provides a rational approach validating the utility of RAI remnant ablation regardless of the patient's risk stratification.

Genomic Profiling of Thyroid Nodules: Current Role for ThyroSeq Next-Generation Sequencing on Clinical Decision-Making.

In recent years there has been an increased awareness of the genetic alterations underlying both benign and malignant neoplasms of the thyroid. Next-generation sequencing (NGS) is an emerging technology that allows for rapid detection of a large number of genetic mutations in thyroid fine-needle aspiration (FNA) specimens. NGS for targeted mutational analysis in thyroid tumors has been proposed as a tool to assist in the diagnosis of thyroid nodules with indeterminate FNA cytology. Results of genomic testing of thyroid nodules and thyroid cancers could also have prognostic implications and play a role in determining optimal treatment strategies including targeted therapies. We provide a critical review of existing studies assessing the performance of the ThyroSeq NGS test for the diagnosis and management of patients with thyroid nodules with indeterminate cytopathology and discuss the applicability of findings from these studies to clinical practice. While there are early indications to suggest a possible utility of data obtained from NGS to aid in prognostication and therapeutic decision-making in thyroid cancer, we recommend judicious use and cautious interpretation of such molecular testing until results of ongoing clinical trials become available. Lastly, we discuss recommendations provided from clinical practice guidelines regarding the use of mutation detection via NGS in the diagnostic evaluation of thyroid nodules.

I-124 Imaging and Dosimetry.

Although radioactive iodine imaging and therapy are one of the earliest applications of theranostics, there still remain a number of unresolved clinical questions as to the optimization of diagnostic techniques and dosimetry protocols. I-124 as a positron emission tomography (PET) radiotracer has the potential to improve the current clinical practice in the diagnosis and treatment of differentiated thyroid cancer. The higher sensitivity and spatial resolution of PET/computed tomography (CT) compared to standard gamma scintigraphy can aid in the detection of recurrent or metastatic disease and provide more accurate measurements of metabolic tumor volumes. However the complex decay schema of I-124 poses challenges to quantitative PET imaging. More prospective studies are needed to define optimal dosimetry protocols and to improve patient-specific treatment planning strategies, taking into account not only the absorbed dose to tumors but also methods to avoid toxicity to normal organs. A historical perspective of I-124 imaging and dosimetry as well as future concepts are discussed.

A Concise Atlas of Thyroid Cancer Next-Generation Sequencing Panel ThyroSeq v.2.

The next-generation sequencing technology allows high out-put genomic analysis. An innovative assay in thyroid cancer, ThyroSeq® was developed for targeted mutation detection by next generation sequencing technology in fine needle aspiration and tissue samples. ThyroSeq v.2 next generation sequencing panel offers simultaneous sequencing and detection in >1000 hotspots of 14 thyroid cancer-related genes and for 42 types of gene fusions known to occur in thyroid cancer. ThyroSeq is being increasingly used to further narrow the indeterminate category defined by cytology for thyroid nodules. From a surgical perspective, genomic profiling also provides prognostic and predictive information and closely relates to determination of surgical strategy. Both the genomic analysis technology and the informatics for the cancer genome data base are rapidly developing. In this paper, we have gathered existing information on the thyroid cancer-related genes involved in the initiation and progression of thyroid cancer. Our goal is to assemble a glossary for the current ThyroSeq genomic panel that can help elucidate the role genomics play in thyroid cancer oncogenesis.