I spoke with oncologist who actually said that this type of cancer in cats is so very rare there is not much literature or documentation on long term treatment/prognosis. He indicated that in his career he has only treated less than 10 cats with this type (due to rarity) and most were in the rear legs - again Fuzz is weirdo with front right scapula osteosarcoma.  He also went on stating that there is no proof that chemotherapy would or would not be beneficial for a long term treatment perspective.  In addition, he said that most he can recall, surgical amputation was most common and near curative form of treatment and cats died from other medical issues.  The only concern he noted was the chance of microscopic disease in chest wall due to narrow incision and location of tumor. Positive note that again this type is very rarely metastatic in cats.  Fuzz doing well despite me now still being worried and uncertainty.  Below I pasted and copied the actual lab report from his biopsy.  Please feel free to read and comment.. it will greatly be appreciated and wanted!

Note from Laboratory
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OTHERBiopsy Source:
EXCISIONALBiopsy Type:
Clinical History: History of progressive mild forelimb lameness (intermittent). Exam revealed ~4-5 cm firmly affixed mass associated with R scapula that seems to also be palpable on medial aspect of scapula/axilla as well. Mild R forelimb muscle wasting with noticable limp. Cytology of mass was most compatible with a sarcoma (see enclosed). R forelimb amputation performed. Sample submitted- R scapula including proximal humerus.
Pathologist's Report
MICROSCOPIC DESCRIPTION: Right scapula: Bulging from and replacing the pre-existing scapula bone, extending out into the surrounding fibrous connective tissue with compression and mild infiltration of regional musculature, there is a densely cellular, unencapsulated, locally infiltrative neoplasm. The neoplasm comprises cells arranged in streams supported by a moderate fibro-vascular stroma; many cells surround and invest narrow ribbons and trabeculae of of unmineralized to poorly mineralized, pale eosinophilic, hyalinized to finely fibrillar material (osteoid) and occasional thick foci of chondroid matrix. Tumor cells are spindloid or stellate with moderate amounts of eosinophilic, finely fibrillar cytoplasm and distinct cell borders. Nuclei are oval or elongated and vesicular with 1-2 deeply eosinophilic nucleoli. There is moderate anisocytosis and anisokaryosis with greater than 30 mitoses per 10 high power fields (400X). There are occasional multinucleated tumor cells (osteoclasts). Frequently throughout the mass, there are multifocal to coalescing, large zones of intratumoral necrosis with associated hemorrhage and fibrous exudation.
MICROSCOPIC INTERPRETATION: Right scapula: Osteosarcoma, osteoblastic, productive Mitotic count: Greater than 30 per 10 high-power fields Angiolymphatic invasion: Not observed Surgical margins: Closest presumptive proximal margin (including striated muscle), 5.2 mm; closest presumptive mediolateral margin, 3.2 mm
COMMENTS: Histopathological examination of the submitted right scapula revealed an osteoblastic, productive osteosarcoma . Feline osteosarcoma (OSA) is rare though 67-90% of bone tumors in cats are histologically malignant. Cats typically develop OSA at an older average age of 10.5 years. The influence of breed predisposition in undetermined, and male cats appear to be more commonly affected. Tumors occur in long bones approximately twice as often as in axial skeleton sites. The disease in cats differs from that in dogs in that the primary lesions occur more often in hind limbs in cats and the disease is reported to have lower metastatic potential in cats compared to dogs.
Reference: Withrow and MacEwen's Small Animal Clinical Oncology, 5th ed, 2013, pp 463-503 and Thompson KG, Pool RR. Tumors in Domestic Animals, 4th ed, 2002, pp 266-283.
PATHOLOGIST: Mark Chalkley, BVSc (Hons), MANZCVS Diplomate, American College of Veterinary Pathologists Direct: 614-438-6304 1-800-551-0998, x86304 E-mail: Mark-Chalkley@IDEXX.com The patient clinical history provided on the submitted requisition was reported. Veterinarians, please contact the pathologist with any questions. Pet owners need to contact their veterinarian for case advice.