Thyroid Cancer

The paper by Higgins et al published in this issue highlights the important advances that have been made in the treatment of advanced thyroid cancer over the past few years. Patients with iodine-refractory metastatic thyroid cancer have suffered badly due to the reputation of thyroid cancer as being a “good” cancer to have.

Over the past 3 decades, the incidence rate of testicular seminoma has continually risen, and the majority of cases have been clinical stage I.[1] Nevertheless, the overall survival for all testicular cancers has improved significantly (P < .05) over the same period, from 83% to 96%.[2]

Lawrentschuk and Fleshner accurately depict the difficulty in choosing among observation, prophylactic radiation, and adjuvant chemotherapy for clinical stage I testicular seminoma. The physican has competing priorities of avoiding unnecessary treatment while minimizing the overall burden of both therapy and surveillance testing. The patient has to contend with defined risks that exist with any of the three options.

Patients with papillary thyroid cancer typically undergo a triad of consecutive initial treatments, comprising surgery, radioiodine therapy, and thyroid hormone suppression of serum thyrotropin (thyroid-stimulating hormone, or TSH).

Differentiated thyroid cancer, the most common endocrine malignancy, can touch the lives of young and old individuals. It is generally associated with a normal lifespan whether it is completely eradicated or held in check with judicious medical interventions.

There is uniform agreement that initial treatment of high-risk thyroid cancer should include total thyroidectomy, compartmental neck dissection of clinically involved cervical lymph nodes, and radioactive iodine (RAI) remnant ablation.

Low-risk papillary thyroid carcinoma (PTC), by definition, requires careful balancing of the risks of treatment and the risks of the disease.

Radiation from the 1945 atomic bomb blasts in Hiroshima and Nagasaki, Japan, most likely rearranged chromosomes in some survivors who later developed papillary thyroid cancer as adults, according to a new study out of Japan.

Matthew Ringel, MD, and colleagues have received an $11.9 million NCI grant for their research in thyroid cancer. The 5-year grant will fund the group’s work on genetics and signaling pathways in epithelial thyroid cancer. Dr. Ringel is co-director of the thyroid cancer unit at Ohio State University in Columbus.

Genzyme Corp. recently announced that the US Food and Drug Administration (FDA) has approved a supplemental indication for thyrotropin alfa for injection (Thyrogen) to be used in combination with radioiodine to ablate, or destroy, the remaining thyroid tissue in patients who have had their cancerous thyroids removed.

Axitinib (AG-013736), an oral small molecule tyrosine kinase inhibitor (TKI), yielded a 30% response rate in a phase II study of patients with metastatic or unresectable thyroid cancer unresponsive to or not suitable for standard treatment with radioactive iodine.

Bortezomib (Velcade) stops cancer growth in patients with advanced differentiated thyroid cancer who do not respond to the standard treatment of surgery and radioactive iodine, according to a recent study presented at the 77th Annual Meeting of the American Thyroid Association (ATA) in Phoenix.

Most thyroid cancers are slow-growing, easily treatable tumors with an excellent prognosis after surgical resection and targeted medical therapy. Unfortunately, 10% to 15% of thyroid cancers exhibit aggressive behavior and do not follow an indolent course. Approximately one-third of patients with differentiated thyroid cancers will have tumor recurrences. Distant metastases are present in about 20% of patients with recurrent cancer.

In part 2, we address risk assessment and staging, findings that suggest the presence of aggressive tumors, recurrent/metastatic disease, and treatment with chemotherapy and external-beam radiotherapy. Experimental treatments utilizing molecular targets, redifferentiation agents, and gene therapy are covered briefly as well.

AstraZeneca, Zactima, ZD6474, medullary thyroid cancer

The US Food and Drug Administration (FDA) has granted fast-track designation for the investigation of ZD6474 (Zactima) in treating medullary thyroid carcinoma. For advanced thyroid cancer, there is currently no curative modality or approved chemotherapy. ZD6474 also received orphan drug designation last year for the treatment of patients with follicular, medullary, anaplastic, and locally advanced and metastatic papillary thyroid cancer.

Part 1 of this two-part article describes in detail the distinct types of thyroid cancer, as well as risk factors, outcomes, and prognostic factors, with a focus on thyroid cancers of follicular cell origin.

Combined-modality positronemissiontomography (PET)–computed tomography (CT) isbecoming the imaging method ofchoice for an increasing number ofoncology indications. The goal of thispaper is to review the evidence-basedliterature justifying PET-CT fusion.The best evidence comes from prospectivestudies of integrated PETCTscans compared to other methodsof acquiring images, with histopathologicconfirmation of disease presenceor absence. Unfortunately, veryfew studies provide this kind of data.Retrospective studies with similarcomparisons can be used to provideevidence favoring the use of integratedPET-CT scans in specific clinicalsituations. Also, inferential conclusionscan be drawn from studies whereclinical rather than pathologic dataare used to establish disease presenceor absence.

Medicare will grant limited coverage for the use of positronemissiontomography (PET) for certain of its beneficiariessuffering from thyroid cancer, the Centers for Medicare andMedicaid Services (CMS) recently announced. CMS also said that ithad refused a request to provide PET coverage for soft-tissue sarcomabecause imaging techniques currently covered by Medicare providegood diagnostic results.

NEW YORK-An ongoing trial of thalidomide (Thalomid) in patients with aggressive, advanced papillary and follicular thyroid carcinomas produced an early response rate of 76%, according to a report presented at the Mount Sinai School of Medicine Chemotherapy Foundation Symposium XX.

An advisory group to the Centers for Medicare and Medicaid Services (CMS) has delayed a decision on whether to recommend Medicare coverage for positron-emission tomography (PET) with F-18-fluorodeoxyglucose (FDG) in the

WASHINGTON-An advisory group to the Centers for Medicare and Medicaid Services (CMS) has delayed a decision on whether to recommend Med-icare coverage for positron emission tomography (PET) with the radiopharmaceutical F-18-fluorodeoxyglucose (FDG) in the management of thyroid cancer and soft tissue sarcoma.

WASHINGTON-Scientists have concluded that no increased risk of thyroid disease, including cancer, befell children exposed to Iodine-131 released from the Hanford Nuclear Weapons Production Facility in Washington State. According to

ROCKVILLE, Maryland-The FDA has issued new recommendations for administering potassium iodide to reduce the risk of thyroid cancer in children and adults in emergencies involving the release of radioactive iodine into the environment.

The increasing frequency of diagnosis and death of patients with follicular cell-derived carcinoma of the thyroid substantiates the need for a broad understanding of the optimal diagnostic and treatment strategies for this disease. Dr. Angelos has provided a good overview of the treatment modalities and approaches to follow-up for these patients. However, several points require additional emphasis or detail.

The management of well-differentiated thyroid cancer requires a multidisciplinary approach. The majority of patients are diagnosed only after a nodule is palpable. A cytologic evaluation can readily diagnose a papillary thyroid carcinoma but a follicular carcinoma requires determination of capsular or vascular invasion.

Well-differentiated thyroid cancer is something of an anomaly in the field of oncology for two primary reasons. First, the team of physicians who manage the patient consists primarily of endocrinologists, endocrine surgeons, and nuclear medicine physicians instead of medical oncologists, surgical oncologists, and radiation oncologists. Second, there is an extremely high rate of cure with remarkable 10- and 20-year survival rates due to the indolent nature of the tumor, even in the setting of lymph node metastases.

Fluorodeoxyglucose positron-emission tomography (FDG-PET) detected recurrent cancer 50% more often than did conventional imaging in people with thyroid cancer who had indications that their cancer had recurred, according to results of

Selective neck dissection is a procedure that is primarily indicated in patients with clinically negative nodal disease in which there is a high risk of occult metastases. Others have advocated its use for patients with

NEW YORK-Ernst Wynder, MD, founder of the American Health Foundation and a pioneer in preventive medicine, died July 14 at Memorial Sloan-Kettering Cancer Center. He was 77 years old. The cause was thyroid cancer.