Really Large Melanoma Tumors...??

Does anyone have experience with really large melanoma tumors rather than many small ones (especially on the liver)?

BACKSTORY: My 32-year old sister was diagnosed with ocular melanoma four years ago and had her eye removed at the time. A few months ago, she started having mild seizures and other signs that something might be wrong with her brain. An MRI revealed a 6 cm round mass in her brain. After two brain surgeries, we've been told they've successfully removed all of the tumor and she will start radiation as soon as she is well enough.

However, our biggest concern is her liver, which the PET scan revealed is overwhelmingly consumed by active cancer. The disease/tumor seems to be larger than the liver itself (from the scan pictures). My sister appears to be about 8-months pregnant and we now suspect it's a result of the enormous mass on her liver, not, as we previously thought, the remainder of her "baby-weight" from delivering her third child seven months ago. (She has three kids under five, so she really wants to beat the odds and kick some serious melanoma butt!)

After receiving the PET scan results, we were told that this presentation of melanoma was unusual--in fact, the oncologist said it was a first in his career. He'd never seen such a large melanoma tumor. He seemed to indicate she'd need to start chemo ASAP, but we weren't given any specifics. At the time, the attention seemed to be completely focused on my sister's large brain tumor (understandably).

So far, it seems as though most individuals have experienced several small tumors, not one or two extremely large ones. Has anyone heard of/experienced having very large melanoma tumors in their liver or elsewhere in their body?

As others have previously stated, this forum is about the only encouraging thing I've found online when it comes to metastatic melanoma and I really appreciate all of the support.

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