[Joan M]

Thank you for your replys and insight.

Ceesun, have you had mets any place else besides the lung? Did you have lung surgery to remove the first met or did it go away with systemic therapy?

Sassy, you have a good point about whether a lung nodule can be HER2+. I had also been wondering about that but never asked my onc (I do know that Herceptin was used in lung cancer trials and it failed miserably). Lani seems to have addressed the issue by discussing the different pathways.

Even though the nodule tested HER2 positive (immunostain), the biopsy as well as the surgery pathology reports favored a diagnosis of breast cancer based on the comparison with my original breast cancer slides. The biopsy report read: the tumor cells show immuoreactivity for CK7 and Her-2/neu (c-erb B2) (3+). They are negative for CK20, TTF-1, PE10, ER, PR and Brst-2.

The only difference between the biopsy and the surgery reports was that the surgical report tested positive for Brst-2.

My onc said that TTF-1 is a strong marker for lung cancer. From what I've read, some of the confusion may be related to CK7 testing positive and CK20 testing negative, as I think this is also consistent with lung cancer.

After the surgery, the tumor was also tested for EGFR. That was done by mistake. I had asked for a HER2 FISH test and instead EGFR was done. The results were positive, EGFR gene copy number = high polysomy; total nuclei counted = 60; FISH probes = EGFR CEP7.

When they finally got around to testing for HER2 with FISH, the results were: Interphase FISH results are consistent with HER2 amplification. Between 10 and 27 HER2 signals/cells were detected. These are abnormal and consistent with HER2 amplification.

Lani, You make a good point about RFA, and I've been shying away from that procedure anyway because the outcomes aren't that good. On the other hand, it's an alternative for someone who can't tolerate lung surgery and gives them an option. Thanks for the info about Dr. Herbst. I'm going to check into it.

Joan