Endocrinologists bring attention to medullary thyroid cancer

BOSTON — Medullary thyroid cancer accounts for just 4% of all thyroid cancer cases, but “these tumors can cause a lot of damage,” according to Richard T. Kloos, MD.

There is very little guidance on how to manage this disease, he told Endocrine Today at the American Thyroid Association Frontiers in Thyroid Cancer meeting.

Medullary thyroid cancer (MTC) presents as a sporadic tumor in three-quarters of patients, or as part of an autosomal dominant inherited disorder in others. The different types include: sporadic, with or without a somatic RET mutation; familial MTC; and multiple endocrine neoplasia 2 type A or B. All patients with this tumor must get genetically tested because it alters their care and others in the family may be at risk of not only MTC, but also pheochromocytoma and primary hyperparathyroidism, he recommended.

“Sadly, our cure of metastatic disease is low,” said Kloos, who is professor in the divisions of endocrinology and metabolism and nuclear medicine at The Ohio State University. Patients with medullary thyroid cancer have a 10-year relative survival of 75% and just under half of all patients present with stage 3 or stage 4 disease and have a much lower survival. Advanced stage at diagnosis, extent of nodal disease and distant metastases are all prognostic factors for adverse outcomes.

With medullary cancer, “we often play a chess game — we need to be strategic because the goal is not to hurt a patient, especially one that we cannot cure, yet get them to live as long as possible, and to know when to be aggressive and when not to,” he said.

Kloos suggested collaboration with oncologists for patients with advanced disease, as very few physicians have enough experience with this cancer or with emerging new treatment options and clinical trials. The ATA is currently developing guidelines to shed light on the management of this disease. – by Katie Kalvaitis

Medullary thyroid cancer is a very small percentage of thyroid cancer. The problem is the average person practicing medicine does not see many cases and physicians do not have a lot of information. To manage this, there needs to be many people involved — we need a multidisciplinary team.

– Ernest L. Mazzaferri, MD

Professor Emeritus of Medicine and Physiology, Ohio State University

For more information:
Kloos RT. MTC genotype-phenotype correlations and their natural history. Presented at: American Thyroid Association Frontiers in Thyroid Cancer; July 11-12, 2008; Boston.