I'm sorry to hear that you are in such a complicated and worrisome situation. I really have no answers to the technical questions, such as what the mass in your atrium might be if it is not a blood clot or a tumor. Answering that question is the purpose of further testing, and as difficult as it is to be patient, I do not see any alternative to taking things as they come, step by step. It is the same with the absence of blood draws. I have not had cancer and am not a doctor, so I think your own oncologist is the best source to clarify that issue for you.
If you do not get a good answer about the blood draws from your own oncologist, consider getting a second opinion from a different oncologist -- or perhaps just ask your PCP to help you understand the situation better. There are also books available that might help, such as The Breast Cancer Survival Manual, by John Link MD, and there are specialized online support forums on breast cancer.
Certainly, you do not want your disease to advance to stage 4, but if it does, it is not an automatic death sentence. Breast cancer is one of the most-researched types of cancer, and treatment strategies are advancing every day. There now are patients who were diagnosed with stage 4 breast cancer who have recovered and have lived for a long time with no evidence of disease.
Please continue reaching out for support, both from your own medical experts and from your real-life and online peers. There is a Breast Cancer Community here on Medhelp that looks to be fairly active. There are a lot of other breast cancer patient forums on other sites on the internet. I believe that somewhere out there is a patient who has successfully gone through exactly what you are going through now.
Last but not least, please consider getting treatment for anxiety. When people have a lot of "what if" type questions, it is a tip-off that anxiety is an issue, in and of itself. I'm not minimizing the very real problems that you are trying to deal with in your life, but the anxiety causes additional suffering, and you don't need that. There are psychotherapeutic and pharmaceutical treatments that can be very helpful in coping with the emotional stress of even an extreme situation. Good luck.
Thank you so much for responding to my post. In regards to my receiving chemo, at the present time I am only receiving Herceptin. This is because I started receiving it in February of 2014, along with all of the other needed chemo drugs. I completed the full regimen in August except for the Herceptin. I go every three weeks to receive the Herceptin until February 2015. My oncologist said that she feels I no longer need blood draws because I am only receiving the Herceptin. I just wonder how I would know if the cancer has returned if no one is monitoring my markers? When I was first diagnosed with stage 3 breast cancer my Oncologist said that I would have to be monitored closely because she said there is a good chance of the cancer coming back, and if it moved beyond the breasts that I would be classified as stage 4, which is incurable? I also completed 33 rounds of radiation. In the past I have never had a problem with high blood pressure but at one of my most recent visits to the heart doctor, he checked my blood pressure three times, and said it was high. He said they would have to keep an eye on my blood pressure in the future. I wonder if it is caused by all of the stress from this blood clot. I am afraid that if they remove my port or reposition it I may have a stroke or it will cause the blood clot to move? I just wonder if it turns out that it is not a blood clot or cancer in my heart , then what could it possibly be? Please respond back if you have any answers or suggestions.
I'm so sorry you are having these problems. The best advice I can give you is to take one step at at time, and go ahead and have the test where the doctor puts the tube down your throat and gets a better look at the clot. I think the test that he is probably wanting to do is a trans-esophageal echocardiogram (TEE). If I'm right, it will be an echo wand that he puts down your throat. Images of the heart from a TEE are clearer and more detailed than those from the echocardiogram that you had before, where I assume a technician moved an echo wand around the outside of your chest. (That kind of echo is called a trans-thoracic echocardiogram, because the echo wand is sending sound waves through your chest wall.)
It is vanishingly rare, almost unheard of, for cancer to metastasize to the heart itself. Heart muscle cells do not multiply, at least not to any significant degree, and so there is little potential for them to multiply out of control. Sometimes a primary cancer will metastasize to the pericardium (which is an enclosed "sac" of tissue that contains the heart), but pericardial tumors are found on the outside of the heart, and if I understand you correctly, your doctors can clearly see that this mass is inside one of the heart chambers. So it is probably not a cancerous tumor that is inside your atrium. If, after you have this next test, your cardiologist is still not sure what the mass is, I would ask for a consultation with a radiologist.
The most obvious explanation of what is going on, to my mind, is what has already been mentioned: that the catheter has moved down into the right atrium and is rubbing on the interior wall of the atrium and has caused a clot. Assuming it is a clot, the doctors will probably want to reposition or replace the catheter. If they don't propose that, I would directly ask about it, because it stands to reason that until it is repositioned or replaced, it will continue to cause a problem.
If your cardiologist has no answer as to why the clot is not dissolving by means of coumadin, I would ask for a consultation with a hematologist. As for your oncologist's not wanting to do blood tests for your cancer markers in the meantime, may I ask if your chemo been suspended until the issue of the blood clot is resolved? If so, then the lack of blood draws is probably because the purpose of the blood draws is to monitor the progress of the chemo, and there is no need to monitor the progress of the chemo until the chemo can be resumed.
I hope that all of your questions can be quickly answered by your doctors and that the obstacles to your treatment are quickly removed. Good luck.