Diagnosis

I was diagnosed with Breast Cancer approx 5 yrs ago and was labeled CUP. I also had several nodules on both lungs but were at the time too small to diagnose. I was treated with heavy chemo. Recently during a follow-up CT Scan the nodules on my lungs have grown and 1 large nodule lit on the PET Scan. I had lung surgery and had 4 areas removed . They believe it is a slow growing form. Recently I had testing done on the old and new tissue and a Molecular test. Both test showed a possibility of Thyroid or Skin cancer, but my blood does not show Thyroid. Because it was in my lungs they are staging it as 4.  They decided to wait on the chemo treatment and monitor the activity with CT Scans every 2 months.  Part of me is nervous about waiting and the necessity of every 2 montsh , but the other part doesnt want to be treated if they are not sure what type of cancer they would treat.  I have been a unique case to them.  I trust my doctor completely, but he too seems a bit perplexed by this.  I would appreciate any feedback I could get. Thank you.

[Kamal S Saini, MD, MRCP (UK), DM]

Hi,
A cancer if unknown primary (CUP) is a diagnosis that is made when a metastatic cancer is detected, but all appropriate tests fail to reveal the primary (original organ where the cancer first started). Metastatic cancer results when cancer cells from the primary organ travel via blood stream or lymph fluid to a distant site and grow into a nodule or cancerous mass. CUP generally tends to be difficult to manage.
Recent tests (perhaps including immunohistochemistry markers) have indicated that the primary or original organ in your case may have been the thyroid or skin. However, these results are only suggestive, not absolute.
A 5-year relapse-free-interval indicates that you have a less aggressive form of cancer. You have done very well so far! You have also had surgery to remove 4 metastatic lung nodules, and I assume that you have no active sites remaining.
There are no firm established guidelines on how to proceed in cases such as yours.  The oncologists' experience and knowlege comes to the fore in such "grey-area" cases. The treating team of oncologists and the patient must together discuss the various options available and select the one that is acceptable.
However, a close watch definitely needs to be kept, and the 2 monthly scanning (with CT or even a PET-CT) is logical.
Please feel free to post a follow-up question if you need more clarity on any issue.
All the best, and God Bless!