Plasmacytoma or Myeloma

Im a little confused as to the difference between a solitary
plasmacytoma and Myeloma, Im of the understanding that a plasmacytoma
is caused by a defective plasma cell in the bone marrow, that self
replicates and forms a lesion of the bone, these defective cells
collect as a tumour that in itself is often radiation responsive.

Upon successful destruction of the plasmacytoma, I assume chemotherapy
is not applied until the plasma cell count in the bone marrow is above
a certain threshold, when does this then become MM and what is the
specific difference,

One more thing, is it possible that MM could already be present when
only one lesion is found?

Sorry if it seems like a thousand and one questions, but Im just
getting ready incase my Dad is hungry for information.
Last week I had never even looked at Cancer now its my lifes work. I
wish to hell it wasnt but this is real and I feel I owe it to my Dad
to help as much as I can.

"Ricardo" <richard3009650@hotmail.com> wrote in message
news:1180694680.690688.175330@m36g2000hse.googlegr oups.com...
> Im a little confused as to the difference between a solitary
> plasmacytoma and Myeloma, Im of the understanding that a plasmacytoma
> is caused by a defective plasma cell in the bone marrow, that self
> replicates and forms a lesion of the bone, these defective cells
> collect as a tumour that in itself is often radiation responsive.
>
> Upon successful destruction of the plasmacytoma, I assume chemotherapy
> is not applied until the plasma cell count in the bone marrow is above
> a certain threshold, when does this then become MM and what is the
> specific difference,
>
> One more thing, is it possible that MM could already be present when
> only one lesion is found?
>
> Sorry if it seems like a thousand and one questions, but Im just
> getting ready incase my Dad is hungry for information.
> Last week I had never even looked at Cancer now its my lifes work. I
> wish to hell it wasnt but this is real and I feel I owe it to my Dad
> to help as much as I can.
>

They are the same disease. MM is generalised, with multiple lesions, and
usually involving the bone marrow. Plasmacytoma is, if you like,
"non-multiple myeloma"

Treatment for plasmacytoma is radiation, and a proportion of patients are
cured.
Treatment for MM is chemo, +/- radiation, and is not curable.