Why is the first surgery you best chance to cure/ remove cancer? (4)
- less time to metastasis
- less seeding
- microscopic disease (dirty margins- cells left behind and regrowth of cancer)
- more tissue for closure (if you have to go back and remove more, you have less tissue)
What are overarching surgical principals for oncologic surgery? (6)
- remove biopsy tract (b/c it's contaminated with cancer cells)
- early vascular ligation (so cancer cells don't disseminated through venous system)
- surgical planning
- wide margins
- gentle tissue handling
- change instruments/ gloves after touching cancer (cancer is like contamination)
Measure lateral margins in ____________; measure deep margins in ____________.
centimeters; terms of fascial planes
What are the principals of biopsy techniques? (6)
- don't place a drain in a biopsy site! remove the biopsy tract (contaminated)
- incisions of the extremities should be made longitudinally
- take large pieces to optimize chance of getting an answer
- no cautery or laser (ruins tissue for pathologist to assess)
- don't deform sample
- properly fix biopsy in formalin
What are types of incisional biopsies? (5)
- wedge biopsy
- punch biopsy
- jamshidi biopsy
- michele trephine
You ____________ before an excisional biopsy.
should have a diagnosis (by FNA or punch)
When can you utilize a tru-cut biopsy?
palpable lesion OR by US or CT-guided technique
Describe a tru-cut biopsy needle.
- needle with slot, sheath that cuts
- insert entire sheath, then exit slotted needle from sheath, traps biopsy, return needle to sheath
When can you do a wedge biopsy?
visible, superficial lesion [create wedge with scalpel]
When can you perform a punch biopsy?
visible, superficial lesion
What is jamshidi biopsy useful for?
bone biopsy; must be palpable lesion, found by radiography/ fluoroscopy/ US/ CT-guided
What is michele trephine used for?
- visible lesion, guide with imagining
- used in large animal
Once you identify a mass, what is the next important step before surgery?
stage the lesion- what is it, where is it, how bad is it, TNM system
What is debulking?
- margins: intracapsular, removed in pieces--> macro- and microscopic disease left behind
- least ideal way to treat cancer
- usually just palliative OR combined with adjunctive therapy
What is marginal surgery?
- margins: outside the pseudocapsule--> microscopic disease usually left behind
- ideal way to treat benign cancers
What is wide excisional surgery?
- margins: rim of lateral and deep margins around the tumor--> usually no local disease left behind
- ideal for malignant cancer tumors
What is radical surgery?
- margins: structure or compartment removed (limb amputation, organ removed)--> no local disease left behind
- altered cosmesis
When you remove a mass from a patients, ALWAYS...
- submit for histopathology (diagnosis, margins, grading)
- don't leave this decision up to the owner.... JUST SUBMIT IT (build it into your surgery cost)
What ways are mammary tumors approached? (5)
- regional or radical mastectomy (cats- ALWAYS radical mastectomy)
- may also want to remove regional lymph nodes
- mammary tumors have 50% chance of being malignant in dogs; almost always malignant in cats
Inflammatory mammary carcinomas are managed by...
NOT SURGERY CANDIDATES; managed medically.
What are ways to approach oral cancer?
- [based on how much bone we are removing]
- mandibulectomy, maxillectomy (rim excision, rostral, segmental, caudal, total unilateral)
Oral neoplasia surgical dose is based upon... (4)
tumor type, location, extent of local disease, metastasis [dogs do wonderful after oral surgery, cats are much harder to manage]
Benign cutaneous lesions are treated with ___________.
Cutaneous mast cell tumors need what margins?
- wider lateral margins with higher grade of tumor
- 1 fascial plane deep
Soft tissue sarcomas margins are...
- 3cm lateral
- 1-2 fascial planes deep
Vaccine-associated fibrosarcomas in cats margins are...
- 3-5cm lateral margins
- 2-3 fascial planes deep
- [very extensive surgery]
GI tumors usually require __________ margins.
wide (6cm lateral margins on either side)
Lung neoplasia treated by surgery is usually...
primary lung tumors only (we don't remove lung mets)
What are indications for lymph node removal? (3)
metastasis, inconclusive FNA results, part of a radical surgery
What are indications for benign tumor removal? (6)
- mechanical obstruction
- rapid growth
What elective procedures can prevent cancer? (3)
- spay: decreased mammary cancer if spayed young
- castration: decreased testicular cancer, perianal adenoma
- cryptorchid castration: crypts have higher risk of cancer