Hemangiosarcoma Flashcards
describe the etiology and tumor biology of hemangiosarcoma
cell of origin: endothelial cells
etiology: not completely understood
-dermal HSA: strong link to UV exposure
biology:
-approx 50% have mutations in PTEN (a tumor suppressor)
-high expression of VEGF (pro-angiogenic peptide
describe the anatomic sites where HSA is found
- spleen: COMMON
- skin, right atrium/auricle, and liver: less common
- bone, retroperitoneal: rare
-but IS one of the ddx for a primary bone tumor
describe the biological behavior of HSA
- highly locally invasive
- highly metastatic: origin is endothelial cells that have direct access to blood vessels (hematogenous route)
-exception: stage 1 cutaneous HSA
-target organs of metastasis: lungs, liver, regional lymph nodes, omentum, mesentery (when a splenic mass ruptures, now HSA has access to entire abdomen)
-most common secondary/metastatic brain tumor in dogs!
- rapid growth!
describe the signalment of dogs affected by HSA
- older dogs
- breeds:
-germa shepherds
-goldens
-labradors - cutaneous location: lightly haired, lightly pigmented dogs that like to sunbathe (pitties)
describe the common presenting history of HSA
- vary from mild lethargy/inappetance to collapse and hypovolemic shock
2 +/- intermittent periods (over days to weeks) of lethargy or collapse with recovery
- cutaneous HSA often red, ulcerated, and may bleed frequently
describe physical exam of HSA
- can be normal!
- cranial organomegaly +/- palpable mass possible
- acute to chronic blood loss
-pale MM
-weak to bounding pulses
-tachycardia
-low body temp - muffled heart sounds secondary to pericardial effusion
- cutaneous/SQ mass
describe what to do in the case of hemoabdomen/splenic mass
- stabilize the patient!
- bloodwork:
-CBC: thrombocytopenia, anemia (regen v. nonregen), schistocytes possible
-chem: liver value elevations (poor perfusion v. metastatic disease)
-clotting profile: PT/PTT often prolonged; approx 50% have signs consistent with DIC - abdominocentesis or pericardiocentesis
-ultrasound guided (pericardio, but abdomino can be done blind)
-non-clotting hemorrhagic effusion: PCV fluid = PCV peripheral blood
-fluid cytology usually not helpful - imaging: site dependent
-rads: important for staging (r/o metastasis)
–AXR: peritoneal effusion, cranial abdominal mass effect
–CXR: globoid heart, less likely to help with dx
-abdominal ultrasound
-echocardiography
-cross-sectional imaging (CT/MRI)
describe differential diagnoses for splenic mass
- benign: hematoma, hemangioma
- malignant: HSA vs others
ruptured splenic mass:
-double 2/3s rule is an okay estimate
-step 1: 2/3 malignant, 1/3 benign
-step 2: 2/3 of malignancies are HSA
-may be as high as 65-70% of all are HSA
incidentally noted splenic nodules: 70% benign
only way to know for sure: histopathology
bigger masses may be high % benign (not reliably though)
-higher mass to splenic volume ratio: if whole spleen is a mass, is more likely benign bc has been growing so long and hasn’t killed dog yet
-higher splenic weight as a % of bodyweight: same thought as above
describe clinical staging of HSA
TNM
T: primary tumor
T0: no evidence of tumor
T1: tumor less than 5cm diameter and confined to primary site
T2: tumor 5cm or greater or RUPTURED, invading SQ tissues
T3: tumor invading adjacent structures, including muscle
regional lymph nodes: N
N0: no regional LN involvement
N1: regional LN involvement
N2: distant LN involvement
distant metastasis: M
M0: no evidence of distance metastasis
M1: distant metastasis
stages:
I: T0 ot T1, N0, M0
II: T1 or T2, N0 or N1, M0
III: T2 or T3, N0, N1, or N3, M1
splenic HSA: most have a ruptured mass at initial presentation (T2), making them at least stage II!
important staging distinction in cutaneous HSA: T1 v T2
-T1: isolated to dermis, not invading below basement membrane = stage 1 = good prognosis
-T2: invading into SQ = stage 2 = more guarded prognosis
how do you stage HSA?
- chest rads/CT
-3-view chest rads or thoracic CT
-CXR: can look diffuse interstitial/miliary, harder to interpret in the lungs of older dogs so may make sense to send out for review - abdominal ultrasound (or CT)
-part of complete staging
-key organs: spleen, liver (nodules in older dogs aren’t always metastasis), LNs, omentum and mesentery, kidney, retroperitoneum - echocardiography: up to 24% of splenic HSA have concurrent cardiac mass
describe HSA treatment
- surgery:
-full abdominal explore at time of surgery and biopsy of abnormalities (also part of staging)
-splenic massa: splenectomy
-cutaneous: STS margins (2-3cm, 1 fascial plane deep)
-cardiac: very rarely right auricle mass might be resectable
–pericardectomy: to prevent tamponade, resulting from bleeding events, may prevent acute death but does not extend survival - radiation therapy: if nonsurgical
-palliative protocols for cardiac HSA
-impact relatively unknown
-difficult to treat with high doses due to movement of heart - chemotherapy:
-best outcome: surgery + chemo (exception is stage I cutaneous HSA)
-agent of choice: doxorubicin IV q2-3 weeks 5 times
-chemo alone: no benefit to splenic HSA, but doxorubicin extends survival time in cardiac HSA
describe complementary and alternative therapies for HSA
- yunan baiyao:
-herbal remedy
-mechanism: enhanced surface glycoprotein expression on on platelets, might be mildly cytotoxic to HSA cells
-controversies regarding manufacturing: inclusion of pangolins in product, consistency of product - aminocaproic acid: prevents fibrinolysos
- tranexamic acid: prevents fibrinolysis
might help with small bleeding events but aren’t likely to prevent/stop large bleeds
- polysaccharopeptide (mostly FYI)
-bioactive component of cariolus versicolor (turkey tail) mushroom
-commercial product: I’m Yunity; antitumor activity in vitro
-small double blind clinical trial showed very little toxicity, delayed progression of metastases, improved survival times
-INTERPRET WITH CAUTION (small trial, very expensive product)
describe follow-up for HSA
- splenic HSA: AUS and CXR q2-3 months
- cutaneous: q3m PE and re-staging (AUS/CXR)
-patients with stage I UV-induced lesions: high risk for more lesions (regular PE very important), low risk for metastasis (so +/- on AUS/CXR)
-high risk of local recurrence
describe HSA prognosis
- bleeding splenic mass:
-stage 2:
–surgery alone 2-3 months
–surgery + chemo: 4-6 months
-stage 3: short (usually weeks), may elect euth prior to sx
- cutaneous (completely excised)
-stage 1 (not invasive into SQ): good prognosis (>2 years) but high recurrence rate/new lesion rate
stage 2 (invasive into SQ): good with aggressive tx (surgery + adjuvant chemo) up to 18 months
- cardiac:
-surgery (rare) + chemo: approx 6 months
-chemo alone: 3-6 months
RT: TBD
describe feline HSA
- most commonly skin/SQ and abdominal
- skin/SQ behaves similar to other STS (soft tissue sarcoma)
- spleen (and other abdominal sites): behave similar to dog splenic HSA
