Significance of Surgery Options for Papillary Thyroid Cancer

Extent of Surgery Affects Survival for Papillary Thyroid Cancer is a paper published in the Annals of Surgery. It is authored by Karl Y. Bilimoria, MD, David J. Bentrem, MD, Clifford Y. Ko, MD, MS, MSHS, Andrew K. Stewart, MA, David P. Winchester, MD, Mark S. Talamonti, MD, and Cord Sturgeon, MD, MS. The paper takes note of the encouraging fact that papillary thyroid cancer is the most common but, at the same time, least aggressive form of thyroid cancer. An excellent prognosis is the norm for PTC.

But the paper also notes a controversy that has centered on surgical options with respect to tumors that are less than 4 centimeters in diameter. It is this controversy about which the referenced study is concerned namely, which of the surgical options is optimal. The study focused on the hypothesis that total thyroidectomy yields improved outcomes compared with lobectomy. 52,173 patients, who underwent surgery for PTC from 1985 to 1998, were the basis for the data generated. The study sought to answer the question of whether total thyroidectomy improved long-term survival rates for PTC patients. Also targeted was the issue of whether total thyroidectomy was associated with a decreased risk of death for tumor sizes exceeding a specified threshold.

The paper noted that, for the sizable group studied, lobectomy procedures on tumors, that were equal to or greater than one centimeter, resulted in a higher risk of death. For tumors smaller than one centimeter the difference between lobectomy and total thyroidectomy with respect to survival was not statistically significant. Note the conclusion in the words of the authors:

The results of this study demonstrate that total thyroidectomy results in lower recurrence rates and improved survival for PTC ≥1.0 cm compared with lobectomy. This is the first study to demonstrate that total thyroidectomy for PTC ≥1.0 cm improves outcomes.

The Thyroid

Endocrine Web is a wonderful information resource. I'll focus on parts of the site providing information about the thyroid in this blog entry. Let's start with Your Thyroid Gland. As the webpage states:

"The function of the thyroid therefore is to regulate the body's metabolism." We notice immediately that the function of the thyroid is essential. Metabolism is a basic function of all life forms. The same web page briefly describes different thyriod disorders in easy to read style.

How Your Thyroid Works is another page at the site. As the author indicates the thyroid gland utilizes iodine, an element found in trace levels in foods we consume. Interestingly thyroid cells are the only ones in our body which absorb iodine. This fact can be exploited in the treatment of certain thyriod disorders. Two important hormones triiodothyronine (T3) and thyroxine (T4) are synthesized within the thyriod, released into our blood and then transported to the cells in our body. Thyriod hormones regulate our metabolism.

Thyroid Nodules is another helpful page. These basic facts are well worth reviewing (quoting):

One in 12 to 15 young women has a thyroid nodule
One in 40 young men has a thyroid nodule
More than 95 percent of all thyroid nodules are benign (non-cancerous growths)
Some are actually cysts which are filled with fluid rather than thyroid tissue
Most people will develop a thyroid nodule by the time they are 50 years old
The incidence of thyroid nodules increases with age
50% of 50 year olds will have at least one thyroid nodule
60% of 60 year olds will have at least one thyroid nodule
70% of 70 year olds will have at least one thyroid nodule

As we have seen thyriod hormones are connected with the function of mitochondria. But what are mitochondria? Mitochondria are organelles (compartments within cells) surrounded by two membranes. Within the inner membrane are contained enzymes vital to energy metabolism (the source of the energy we need to function). Mitochondria are about the size of bacteria, meaning they are much smaller than our own cells. Hundreds of mitochondria are found in each cell. Mitochondria frequently and accurately are dubbed the power plants of eukaryotic cells (the more complex cells composing multi-celluar organisms). Carbohydrates and other constituents of the food we consume are metabolized (broken down chemically) in mitochondria. Energy is stored in that process enabling our cells to call on that stored energy when needed.1



1. Biochemistry by Garrett and Grisham; Chapter One.