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Date of last update: 10/21/2017.

Forum Name: Endocrine Cancers

Question: Thyroid cysts - previous Adenoid Cystic Carcinoma/Breast

 lanesharon - Wed Feb 19, 2003 10:23 pm

In 1998, after 4 years of being told that the lump in my breast was a benign cyst (based on mammogram images and FNA's), I chose to voluntarily have it removed. It was adenoid cystic carcinoma (cylindroma, adenocystic) of the breast. It was a large tumor by then and I wanted to kick myself in the butt for not insisting on having it removed four years earlier (my instincts kept telling me it was cancer). I was told that it must have been popping out of the way when the FNA's were done, but I have since been told that FNA's may not be a large enough sample to diagnose this particular cancer.

Over the last couple of years I have had periods of having a sensation of a lump in my throat and at times I have esophageal restrictions (dilation was done with no resolution). I had cervical spine fusion done this year to correct cervical spine fractures and hoped that the lump feeling would go away. It did not. Over the last couple of months I have had a recurring sore throat and in the last few weeks a hoarseness has developed. I was recently put on synthroid for symptoms of a thyroid condition based on family history and systemic symptoms, not blood test results. At the same time the doctor told me she felt a lump in the left side of my thyroid and ordered an ultrasound.

Report reads "A 5-mm simple cyst of the right lobe is noted. The left lobe of the thyroid has two small cysts with the largest measuring 3 mm. Normal Doppler signal is seen. IMPRESSION: Small cyst-negative for malignancy."

I know that thyroid cysts are common and that I shouldn't be concerned, but my past history of misdiagnosis does concern me. I know that to have AdCC in the thyroid after having it in the breast, has only been reported once before in the literature. But, I have seen lightning strike twice in my job as a cancer advocate. When I asked my PCP today what I should do, he said that I should not worry because the ultrasound can distinguish a cyst from a carcinoma. He also said that the cysts are far too small to biopsy anyway.

I need to ask what you would recommend in this situation if this were your daughter or wife. And I need to ask if cysts are clearly seen in ultrasound? Are they ever misinterpreted? Am I missing something? Thank you for any insight you can give me.
 Dr. Yasser Mokhtar - Mon Mar 03, 2003 10:16 am

User avatar Dear Sharon,

Thank you very much for using our website.

Symptoms of hypothyroidism can be caused by other diseases. That's why to be started on syntroid, you have to have a blood test for the thyroid functions to make sure that you are hypothyroid and that's the symptoms you are having are secondary to hypothyroidism. The importance of obtaining blood tests lies also in the fact that if you will be taking thyroid hormone replacement, this should be monitored and the synthroid dose adjusted accordingly.

About thyroid cysts, the ones that you have are small to be considered for biopsy. The cut off for the size is usually 10 mm for any thyroid lesion to be considered for biopsy even if ultrasound guided. Usually the ultrsound is good at telling if this is a benign looking cyst or not as there are ultrasonographic signs of malignancy that can be detected.

About metastatic disease to the thyroid gland, it is a rare occurence and there are tumours that are known to cause metastases, at top of the list is kidney cancer, breast cancer is one of the malignancies that can cause metastases to the thyroid as well.

You have a history of breast cancer and thyroid disease, how to tell whether the thyroid disease that you have is because of the breast cancer or not?

There are tumour markers that are used to follow-up the recurrence of cancer and they are usually good at that, so if you recurrence of the tumour whether locally in the breast or outside the breast at any site, these markers which can be detected by blood tests are usually elevated. In addition there are more sophisticated x-ray techniques that can be used to check the thyroid gland for any abnormality such as c.t. scans and m.r.i. as well. Recently, the addition of p.e.t scans to the armimentarium of x-ray techniques has served as a great tool to discover metastatic disease to anywhere in the body.

My advice to you is that if you are really worried, wait till you see your oncologist (or go earlier) and ask him about the possibility of you having blood tests for tumour markers for the breast cancer which i suspect you most probably are already having every year or so to make sure that breast cancer is not back and according to what he thinks your risks are (according to the blood tests and other clinical impression) of the cysts in the thyroid being cancer from the breast. If you want to make sure i think the best tool available now is the pet scan which is usually very good at detecting malignancy in the body.

Once more, thank you very much for using our website and i hope that this information helped.

Yasser Mokhtar, M.D.

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