Mast cell tumors in cats behave very differently from dogs - cutaneous MCT is often benign and self-resolving, while visceral (intestinal/splenic) forms are aggressive. Splenic MCT is the most common splenic tumor in cats. Splenectomy costs $1,500-$2,500 with 12-19 month median survival.
Cutaneous MCT: small firm skin bumps; typically benign and regress spontaneously. Histiocytic MCT is unique to cats. Visceral MCT: intestinal (most common) and splenic forms; more aggressive. Splenic MCT is the most common splenic tumor in cats.
Cutaneous: firm skin bumps, may itch. Intestinal: weight loss, vomiting, diarrhea (mimics IBD). Splenic: weight loss, enlarged abdomen, pale gums. Histamine release causes GI ulcers.
FNA: mast cells identified quickly ($100-$200). Skin: FNA or excisional biopsy + histopathology ($200-$400). Intestinal/splenic: abdominal ultrasound ($200-$400) + guided FNA. Blood panel for anemia. Endoscopy + biopsy for intestinal MCT.
Cutaneous: excision ($500-$1,200), often curative. Splenic: splenectomy ($1,500-$2,500), median survival 12-19 months. Intestinal: surgery + chemotherapy, guarded prognosis. H2 blockers manage histamine-related GI ulcers ($10-$20/month).
Cutaneous: $700-$1,500 for diagnosis + excision. Splenic: $2,000-$4,000 for diagnosis + splenectomy + follow-up. Intestinal: $2,000-$5,000+ with chemo.
Siamese cats are at elevated risk for cutaneous MCT, particularly the histiocytic (benign) form. Histiocytic MCT is almost exclusive to young Siamese cats and often spontaneously regresses. Visceral MCT has no clear breed predisposition.
Cutaneous MCT (non-Siamese): good with excision. Siamese histiocytic MCT: excellent - often self-resolves. Splenic MCT: median survival 12-19 months with splenectomy. Intestinal MCT: guarded to poor.
Cats with splenic MCT: monitor for intestinal involvement (common concurrent finding). Check for GI ulcers. Post-splenectomy: follow-up blood panels every 3 months. Biopsy all new skin lumps to distinguish MCT from other tumors.
02/04
Diagnosis + splenectomy + follow-up for splenic MCT.
MCT is covered as cancer by most policies. Covered: FNA, excisional biopsy, surgery (splenectomy), post-operative chemotherapy. Cutaneous MCT excision is covered as cancer treatment; histopathology confirms diagnosis.
Any skin lump documented before enrollment can deny coverage if it later proves MCT. Splenic masses on pre-enrollment imaging are another trap. Enroll before lumps are documented and insist on fresh health documentation at enrollment.
Intestinal MCT and IBD overlap and are hard to distinguish on biopsy. If your cat has prior IBD diagnosis, an insurer may deny MCT coverage as a pre-existing gastrointestinal condition. Common contested dispute in feline oncology.
Splenic MCT surgery + workup reaches $3,000-$4,000; chemotherapy adds more. Verify your policy's annual or per-condition cancer limit covers full treatment. $5,000+ cancer limits provide best feline MCT coverage.
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