Quick synopsis:

Limping in September followed by multiple vet visits and finally a referral to an ortho specialist who did a biopsy.

May 2, amputation.  Diagnosis--histiocytic cell sarcoma (a "nasty, nasty" cancer according to the ortho vet and the oncologist).  Spread to lymph node.

May 10 first round of chemo.  2 weeks later, I dose him the oral chemo.

June 10 third round of chemo.  2 weeks later, I dose him the oral chemo.

July 11 fifth round of chemo.  Lab tests are wonderful!  His white cells are up.  His red cells are up.  He has experienced no vomiting, no diarrhea, and no loss of appetite.  His oncologist wanted him to gain weight, and gain he did--he's up to 74 pounds (although I think he looks better at 70).  But the oncologist said that if he loses weight it usually means the cancer is winning.

Next appointment is August 10.  Keep your fingers crossed for another good checkup.  Perhaps he'll outlive his prognosis (which isn't good).  The oncologist said he's seen only one dog with this cancer survive as long as a year.  He said people that get this cancer are given only 90 days.  Chico has passed the human survival period.  Let's hope he passes the oncologists other patient.