Letter from the Editors

Article Outline

• Copyright

One of the difficulties with nuclear medicine that has often been mentioned in this editorial column is the lack of specificity of the majority of procedures we perform. A notable exception to this, perhaps, is endocrine nuclear medicine, where a wealth of compounds that are aimed at specific diseases have been available for many years. During the last decade, the number of these compounds has increased enormously. Like all other procedures in nuclear medicine, the impact of positron emission tomography (PET) in endocrine nuclear medicine is a powerful one. Several fluorine-labeled compounds are very close to being made generally available so that most clinical practices will have them for routine use.

Dr. Sarkar has reviewed the current status of thyroid disease in nuclear medicine. The single greatest advance in this area has been the introduction of human thyrotrophin, which has altered the way in which patients with thyroid cancer are studied and managed. The increasing role of thyroglobulin has also had a profound effect. Complementing the review of benign thyroid disease is the article by Drs. Lind and Kohlfürst on the respective roles of thyroglobulin, radioiodine imaging, and PET in the assessment of thyroid cancer. The importance of PET in evaluating thyroid cancer has even been acknowledged by Medicare, which has granted a reimbursement for limited indications of PET studies in thyroid cancer. It appears at this time that PET will not replace standard imaging modalities in the management of thyroid cancer, but will assume an important complementary role that is clearly spelled out by Drs. Lind and Kohlfürst.

Focusing again on the neck, Drs. Kettle and O’Doherty have reviewed parathyroid imaging. It appears that the potential for PET here is less promising, since general nuclear medicine approaches to parathyroid imaging have already achieved excellent results. Numerous articles appear on parathyroid imaging every year and Drs. Kettle and O’Doherty have done an excellent job of collating this material and putting together a coherent review of the nuclear medicine approach to parathyroid pathology. The major problems at this point appear to be resolving minor technical details and agreeing on an approach. The role of parathyroid imaging in primary hyperparathyroidism is increasingly appreciated by the parathyroid surgeon and a significant number of contributions to the literature actually come from parathyroid surgeons who have incorporated this procedure into their clinical practice.

The University of Michigan has been a pioneering institution in evaluating the pathology of the adrenal gland and in adrenal gland scintigraphy. Drs. Avram, Fig, and Gross review the current status of adrenal imaging, bringing us up-to-date on this gland, which is responsible for several very different diseases and is imaged with a wide variety of compounds depending upon the underlying pathology. Although biochemistry and computed tomography continue to be the primary modalities for evaluating adrenal gland pathology, the roles of radionuclides and, once again, PET, are prominent ones with the potential to further define the pathology and lead to a correct physiologic diagnosis to complement the anatomic diagnosis.

Closely related to adrenal pathophysiology is the pathophysiology of neuroendocrine tumors, which is reviewed by Drs. Rufini, Calcagni, and Baum. Many neuroendocrine tumors are secretors of hormones that we associate with the adrenal gland. Therefore, the imaging approach to these entities is quite similar. Dr. Rufini and colleagues review their approach to imaging neuroendocrine tumors. In some situations, there is overlap with the procedures described by Dr. Avram and colleagues, but as is the policy of Seminars in Nuclear Medicine, we welcome overlap among the articles so that the reader can be exposed to a wide perspective of approaches to various disease entities. For the most part, the differences in diagnostic approaches between these two articles are minor, but the inclusion of both offers the reader a choice of the best approach for his or her specific clinical practice.

Finally, Drs. Pakzad, Groves, and Ell review the role of diagnostic imaging in pancreatic disease. There still is a considerable amount of work to be done for evaluation of the pancreas to assume a primary role in nuclear medicine; however, there are situations in which fluorodeoxyglucose (FDG)-PET imaging can be of value which are presented in this fine review article. The problem, of course, remains in differentiating inflammation from neoplasm in pancreatic disease.

There are a number of other endocrine organs that are not included in this issue of Seminars. However, the most common entities are thoroughly reviewed in the articles contained here. It is not unlikely that new compounds will be introduced that will give us the capability to play a role in the diagnosis of diseases of the parathyroid and other less common endocrine malfunctions. There even exists the potential to have a role in the evaluation of diabetes. It is likely that the compounds that we will be using and the diagnostic techniques that we will be taking advantage of over the next 5 to 10 years will change dramatically and become increasingly specific.

Nuclear medicine began with endocrine disease in the diagnosis of the thyroid and it is only fitting that endocrine disease continues to be an important part of our practice.