THYROID CANCER DOESN'T ALWAYS LEAD TO SURGERY
How is thyroid cancer treated? Does it always require taking out the thyroid? When is iodine treatment used, and how does that work?
Treatment for thyroid cancer usually involves removing all or part of the thyroid gland. In cases where thyroid cancer is advanced or aggressive, radioactive iodine treatment may be recommended after surgery to destroy any cancer cells that couldn't be removed during surgery. For very small papillary thyroid cancers (less than 1 centimeter in diameter and completely confined to the thyroid on ultrasound examination), it may be reasonable to avoid surgery and monitor them periodically without treatment. This is termed "surveillance" and requires annual imaging of the thyroid with high-quality ultrasound. These small thyroid cancers are low risk for progression, especially in people over 60.
The thyroid is a butterfly-shaped gland in the midline of your neck, about halfway between your Adam's apple and your breastbone. Your thyroid gland produces two main hormones: thyroxine, or T4, and triiodothyronine, or T3.
Thyroid hormones impact many cells within your body. They maintain the rate at which your body uses fats and carbohydrates, help control your body temperature, affect the working of your nervous system and influence your heart rate. Your thyroid gland also produces calcitonin, a hormone that helps regulate the amount of calcium in your blood.
Thyroid cancer is not common in the United States. When it is found, though, most cases can be cured. Surgery to remove all or most of the thyroid, a procedure called a thyroidectomy, is often the first step in treatment.
Thyroidectomy typically involves making an incision in the center of the neck to access the thyroid gland directly. In addition to removing the thyroid, the surgeon may remove lymph nodes near the thyroid gland if the cancer is known or suspected to be spreading outside the thyroid. Then, those lymph nodes will be checked for cancer cells. An ultrasound exam of the neck before surgery can help doctors determine if lymph node removal is necessary.
When thyroid cancer is found in its earliest stage, and the cancer is very small, it may only be necessary to remove one side, or lobe, of the thyroid, and leave the rest in place. In that situation, the thyroid still can function and produce hormones.
When the entire thyroid is removed, lifelong thyroid hormone therapy is required to replace the thyroid's natural hormones and regulate the body's metabolism. In addition to supplying the missing hormone the thyroid normally makes, this medication also suppresses the pituitary gland's production of thyroid-stimulating hormone, or TSH. That's useful, because there's a possibility that high TSH levels could foster the growth of any remaining cancer cells.
If thyroid cancer is found in its later stages, if it's a more aggressive form of cancer or if it is cancer that has come back after earlier treatment, then radioactive iodine therapy may be recommended after the thyroid has been removed.
Radioactive iodine comes in a capsule or liquid that's swallowed. The therapy works because thyroid cells naturally absorb iodine. So when the medicine is taken up by any remaining thyroid cells or thyroid cancer, the radioactivity destroys those cells. Because the thyroid is the primary site where iodine is absorbed by the body, there's a low risk of harming other cells with this treatment. Afterward, the radioactive iodine leaves the body through urine.
If thyroid cancer is not cured with a combination of surgery and radioactive iodine therapy, then chemotherapy, external radiation therapy or other treatment may be necessary. Fortunately, surgery cures most cases of thyroid cancer, and the long-term outlook after the procedure is usually excellent.
John Morris III, M.D., Endocrinology, Mayo Clinic, Rochester, Minn.
SIZING UP KIDNEY STONES
How do doctors decide on the best treatment for kidney stones? When I had a calcium stone, my doctor gave me medication and told me to drink plenty of water until it passed. What makes these stones so painful?
Treatment for kidney stones depends on a stone's size, type and location. As in your case, extra fluids and medication may be all that's needed for some small stones. Other treatment may be necessary when a stone is larger. The pain associated with kidney stones usually is the result of spasms triggered by a stone stuck in the ureter, coupled with pressure in the kidney from urine backup.
Kidney stones form from minerals and acid salts. About 85 percent of kidney stones are calcium-based, typically calcium oxalate. Less common are uric acid stones, struvite stones and cystine stones. Doctors use blood and urine tests to find out what kind of stones are present. If you have passed a stone, a laboratory analysis also can reveal the makeup of the stone.
Many uric acid and cystine stones can be dissolved by taking medication and drinking extra fluids. Calcium-based stones are different, because they don't dissolve. You have to get them to pass through your urinary system or have them removed.
Drinking extra water can help flush out the urinary system, making it easier for a small stone to pass. Medication to relax the muscles in your ureter, the tube that connects your kidney to your bladder, also can help a stone pass more quickly and with less pain.
Kidney stones often can be quite painful. There are several reasons for that. First, the ureter is small and inflexible, so it can't stretch to accommodate a stone. Second, when a stone gets into the ureter, the ureter reacts by clamping down on the stone in an attempt to squeeze it out. Those spasms can lead to significant pain. Third, if the stone is blocking the ureter, urine backs up into the kidney, causing pressure within the kidney.
People often describe kidney stone pain as flank pain that starts under the rib cage and goes down toward the testicles in men or the labia in women. To ease pain, health care providers often recommend over-the-counter pain relievers for those who are waiting for a kidney stone to pass. Sometimes, narcotics also are prescribed.
Stones that are too large to pass through the urinary tract on their own or stones that are causing other problems, such as bleeding, kidney damage or urinary tract infections, usually require more invasive treatment.
One procedure that can break up a kidney stone is called extracorporeal shock wave lithotripsy. It uses sound waves to create strong vibrations that break the stones into tiny pieces. Those pieces then pass out of the body in urine.
Another option to remove a stone in the ureter or kidney is a procedure in which a thin, lighted tube, called a ureteroscope, equipped with a camera is passed through the urethra and bladder to the ureter. Once the stone is located, special tools can snare the stone or break it into pieces that pass in the urine.
If a stone is particularly large, minimally invasive surgery may be necessary. A procedure called percutaneous nephrolithotomy involves surgically removing a kidney stone using small telescopes and instruments inserted through a small half-inch incision in the back.
Because you have a history of kidney stones, if you haven't already done so, talk with your health care provider about strategies you can use to help prevent stones in the future. In many cases, dietary changes, an increase in fluids and, sometimes, medication can help reduce the risk of kidney stones.
David E. Patterson, M.D., Urology, Mayo Clinic, Rochester, Minn.
Mayo Clinic Q & A is an educational resource and doesn't replace regular medical care. Email a question to MayoClinicQ&A@mayo.edu. For more information, visit mayoclinic.org. © 2017 Mayo Foundation for Medical Education and Research. Distributed by Tribune Content Agency LLC. All rights reserved.