Tumor Specific 25% AB Flashcards
Skin/Sq, STS, FISS, GI, endocrine
What percentage of cutaneous tumors are malignant?
20-40%
List the top 4 most common skin tumors in cats.
basal cell tumor (~25%) > MST > SCC ? fibrosarcoma
Predisposing factors for SCC of the nasal planum, pinna, head and neck in cats?
white fur, UV light
Human syndrome xeroderma pigmentosum (XP) results in UV-induced skin cancer because it is deficient in what type of DNA repair?
nucleotide excision repair
How does papillomavirus result in neoplastic transformation?
- interaction of papilloma viral proteins with cellular proteins
- destabilization of p53 by viral protein E6 and inhibition of pRB by viral protein E7
How is disruption of p53 with E6 characterized on IHC?
increased levels of p16 protein
E6 protein of HPV types 16 and 18 interacts with the E3 ubiquitin protein ligase, resulting in ubiquitination and proteolysis of tumor protein p53. E7 inactivates retinoblastoma protein (Rb) by phosphorylation followed by an increase of free eukaryotic transcription factor E2F (E2F) in the cell. This leads to an increase of cyclin-dependent kinase inhibitor p16, that is used as an immunohistochemical marker of HPV-associated OSCC
What percentage of cutaneous SCC in cats in “UV-protected” (unexposed) areas are positive for papilloma virus via PCR DNA amplification?
76%
vs 42% in UV exposed areas
(no correlation in cats between virus and UV exposure; different in people)
What is the most common skin tumor in dogs?
MCT (~17%)
Which mutation is most common in human SCC?
p53
30% dogs
feline actinic keratosis 79%
feline Bowen’s in situ carcinoma 18%
Which gene is affected by a loss of function mutation in GSD resulting in nodular dermatofibrosis? Which cancer is this associated with?
- Birt-Hogg-Dube (BHD) have to be heterozygous or will die
- renal cystadenocarcinoma
Which RAF sand VEGF/PDGFR TKI is associated with rapid development of actinic keratosis and invasive SCC in people?
sorafenib
Which epithelial membrane glycoprotein is specific for BCC?
BerEP4
Incidence of BCC in dogs? At risk breeds?
- 6%
- Cocker Spaniel, Poodle
Histologic subtypes of BCC?
solid, keratinizing, clear cell
Behavior of BCC in dogs?
- low grade malignancy
- local recurrence possible
- no mets reported
Incidence of BCC in cats? Breeds?
- 10-26%
- Siamese, Himalayans, DLH, Persain
BCC behavior in cats?
- ~10% may be malignant based on stroll invasion, vascular invasion, high MI, LN mets
- pulmonary mets have been reproted
Recommended margins for BCC removal?
5-10 mm surgical
Growth pattern of papillomas?
exophytic
Surgical excision is often curative for papillomas that do not spontaneously regress. Which drug can be used for patients with multiple lesions?
azithromycin
Define SCC in situ.
carcinoma that has not penetrated the basement membrane of the epithelium
Causative agent of carcinoma in situ in cats?
Felis catus PV type 1
- when multiple present termed Bowen’s carcinoma or multicentric Papilloma virus induced carcinoma
What is identified on histopathology for UV induced SCC?
actinic keratosis
DFI and MST for cats with solitary SCC in situ of the nasal planum/pinna treated with surgery alone?
DFI 594d (19.8 mo)
MST 675d (22.5 mo)
Alternative treatment for solitary SCC in situ in cat nose/face?
Strontium-90 plesiotherapy
14/14 CR, >3000d OST
Cat breeds at decreased risk for cutaneous SCC?
- Siamese, Himalayan, and Persian
Dog breeds at risk for cutaneous SCC?
Labs and goldens - nasal planum SCC
blood hounds, Basset hounds, standard poodles
Paraneoplastic syndrome associated with cutaneous SCC in cats?
hypercalcemia
Metastatic rate of cutaneous SCC in cats?
5.3% ; primarily LN in 66%
(VCO 2023; reported higher if nasal planum in Withrow ~40%)
Metastatic rate of cutaneous SCC in dogs?
4.39% all LN
Response rate to electrochemotherapy for cats with cutaneous SCC?
82% CR for 2 mo to 3 yr
List the tumors arising from the hair follicle (most are benign).
Infundibular keratinizing Acanthoma
Tricholemmoma
Trichoblastoma
Trichoepithelioma
malignant trichoepithelioma
Pilomatircoma
Malignant pilomatricoma
Treatment for infundibular keratinizing acanthoma when surgery is not possible?
isotretinoin (1.7-3.7 mg/kg/d)
How is malignant trichoepithelioma differentiated from benign?
- invasion into surrounding tissues
- LN involvement
- high MI
- highly metastatic, need wide excision
- AKA matrical carcinoma
How is malignant pilomatricoma differentiated from benign?
- Can be difficult but invasion primarily into bone
- highly metastatic to lungs, LN, bone, mammary gland, and skin
Which breeds are predisposed to sebaceous gland tumors?
Mini schnauzers, beagles, poodles, and cocker spaniels
Which signalment characteristic is common in dogs with sebaceous gland carcinomas?
Intact male
Which proteins have been shown to be expressed in canine cutaneous neuroendocrine carcinoma?
B-catenin and E-cadherin
How do patients with ear canal tumors present?
Mass effect, chronic otitis, partial deafness, pain on opening, mouth, neuro signs
Differentials for tumors of the ear canal.
Ceruminous gland adenocarcinoma (most common in dogs & cats)»_space; SCC, undifferentiated carcinoma, BCC, HSA, MCT, melanoma, and benign fibroma, papilloma, polyps, etc
Predisposed breeds for ceruminous gland adenocarcinoma?
cocker spaniel, GSD
Are benign or maligner ceruminous gland adenocarcinoma more common?
malignant in cat (~70%), unknown in dog
- staging always recommended
Staging scheme for ear canal tumors?
T1 = confined to the external or horizontal canal
T2 = extending beyond the tympanic membrane
T3 = extending beyond the middle ear/bone
Most common surgical procedure for ear canal tumors?
TECA-LBO
cat MST = 42 - 50.3 mo (~4 yr)
dog MST = not reached at 36 mo
PFS for dogs (5) and cats (6) with ear canal tumors treated with 12 x 4 Gy = 48 Gy?
39.5 mo
56% 1 year PFS
Mitosis per 10 hpf associated with more favorable outcome for cats with ear canal tumors?
</=2 MST 180 mo
>/= 3 MST 24 mo
Dog presents with head tilt to the left, bilateral ventral strabismus, OS no menace, elevated 3rd eyelids bilaterally – where is ear tumor?
left middle ear
Dog presents with falling to the left when shaking head, positional nystagmus fast phase to the left and a miotic pupil OD – where is ear tumor?
left brain stem
MST for a cat with ear canal tumor presenting with neurologic signs?
1.5 mo
vs 15.5 mo if not neurologic
List the 3 histologic subtypes described for cats with ear canal tumors and their associated MST.
1) ceruminous gland adenocarcinoma 49 mo
2) SCC 3.8 mo
3) carcinoma of unknown origin 5.7 mo
MST for a cat with an ear canal tumor presenting with extension beyond the ear canal?
4 mo
vs 21.7 mo if no extension
Which factor has been shown to prognostic in dogs with ear canal tumors?
extension beyond the ear canal (T3)
if present MST 6 mo vs 30 mo if not
List the most common malignant digit tumors in dogs?
SCC 47% > melanoma 24% > STS 13% > MCT 8% > OSA 3%
others: round cell sarcoma, adenocarcinoma, malignant adnexal tumor, HSA, LSA, chondrosarcoma, giant cell tumor of bone, synovial cell
What percentage of dogs with digital SCC have multiple digits involved?
3%
Predisposed breeds: standard poodle, black labs, giant schnauzers, setters, rotties
THINK BIG AND BLACK
except doxins and flat coated retrievers
Which limbs are more commonly affected by digit tumors?
thoracic
Predisposed breed to digital melanoma?
Scottish Terrier
Rate of disagreement amongst pathologist when diagnosing digital tumors?
20%
75% doesn’t matter except SCC and IKA
Most common digital tumors in cats?
SCC 25% > fibrosarcoma 23% > adenocarcinoma 22% > OSA 8% > HSA 8% > MCT 7%
others: giant cell of bone, fibrous histiocytoma, sarcoma, melanoma
Which tumor types have been reported to affected multiple digits in cats?
fibrosarcoma, adenocarcinoma, SCC
Acrometastatsis AKA
lung digit syndrome
occurs in cats with lung tumors. Case series 88% of cats had acrometastsis and only 13% primary SCC of the digit
MST cats with acrometastasis?
5 weeks
MST cats with digital SCC treated with surgery?
30 weeks
~7 months
Frequency of bone lysis in dogs with digital SCC? Melanoma?
80% - SCC
5-100% - melanoma
Metastatic rate canine digital SCC?
6%-13% at time of diagnosis
9%-17% later
Subungual may be a BETTER prognosis
Metastatic rate canine digital melanoma?
32%-40% at time of diagnosis
additional 10%-26% after definitive treatment
Recommended treatment for most digital tumors?
partial foot amputation
Cytology of SCC + lysis of P3 – what is the metastatic rate?
20-30%
1 year and 2 year survival rate k9 SCC of the digit treated with surgery alone?
1 year = 50-80%
2 year = 18-62%
better if subungual
1 year = 95%
2 year = 74%
1 and 2 year survival rate K9 digital melanoma treated with surgery alone?
mst 12 mths
1 year = 42% - 57%
2 year = 13-36%
- other study added carbo with no difference in survival: 1 year 89%, 2 year 67%, MST 1350d (45 mo)
MST, 1 year, and 2 year survival rate for dogs with melanoma treated with digit amputation and murine xenogeneic vaccine +/- chemo and RT?
JVIM 2011 (Manley et al)
MST 476 days (15.8 mo)
1 year 63%
2 year 32%
Metastasis poor prognosis (distant>local)
Prognostic factors for digital melanoma?
- Distant mets – poor
- Lymphatic invasion – poor
- MI ≥3 in 10 random hpf – poor
- ≥20% nuclear atypia – poor
- Presence of ulceration – poor
- ≥15% Ki67 index – poor
- Extension beyond the dermis – poor
- tumor thickness >0.95 cm - poor
MSU panel from dog with digital melanoma:
- Ki67 10%
- >30% nuclear atypia
- MC >4/10hpf
What is the prognosis and which factor is swaying that?
Poor - both MC and nuclear atypia
ki67 okay >/= 15% assocaited with poor prognosis
Most common location for cutaneous SCC in dogs? Cats?
abdominal skin - dogs
nasal planum - cats
Rate of histologic changes suggestive of solar radiation in cat and dog SCC?
57%
Which histopathologic changes of cutaneous SCC are more likely to be associated with aggressive behavior?
presence of myofibroblasts, desk-plastic reaction, and incomplete margins
(suggest metastasis and poorly differentiated disease)
Which histologic factor has been shown the be associated with a more favorable survival in dogs with cutaneous SCC?
actinic change (solar) MST 1359d (45.3 mo, ~4 yr)
vs no solar changes 608d (20.2 mo, ~1.5 yr)
Which procedure can be used in cats with nasal planum SCC following curative intent surgery (nasal planectomy) to maintain aesthetics?
Lip to nose flap - minimal SE
OST for cats receiving SRT for facial SCC? AE?
118-991 days
Acute: alopecia, epilation, erythema
Late: alopecia, pigmentation, leukotrichia
4 mths to .2.5 year?
Cats with nasal planum SCC treated with strontium 90 have a favorable prognosis with DFI reported of ~2 years. Which protocol has been shown to result in a significantly longer DFI?
fractionated better than single dose protocol
Response rate of nasal planum SCC to Sr90? Local recurrence rate?
~75%
17%
Prognostic factors associated with response to Sr90 in cats with nasal planum SCC?
early stage disease, absence of concurrent problem, CR - favorable
Response rate of feline SCC of the head and neck to photodynamic therapy?
84% RR (61% CR, 22% PR)
PFS mean 35 mo
Does oclacitinib predispose to cancer?
no
Which pathway has been found to be persistently activated in cutaneous papillomas in dogs?
PI3k/akt/mTOR
True or false: Felis catus papillomaryvirus type 2 virus-like particle vaccine reduces FcaPV-2 viral loads?
False
- but is safe
What is the DFI for cats with incompletely excised sarcoids of the face?
250 d (~8.5 mo)
What is the recurrence rate of feline facial sarcoids following surgery?
40.5%
11.1% even with complete margins
Incidence of STS in dog? Cat?
Dog - 15% all skin/sq tumor
Cat 5%
What are predisposing factors to STS in dogs?
- RT
- Trauma
- foreign body
- orothopedic implatns
- Spirocerca lupi
Subclassifications of STS
fibrosarcoma
perivascular wall tumor
peripheral nerve sheath tumor (non-brachial plexus)
liposarcoma
myxosarcoma
pleomorphic carcoma
malignant mesenchymoma
undifferentiated sarcoma
Biologic behavior of STS
locally aggressive with low to moderate risk of distant metastasis
What is nodular fascitits?
AKA fibrzomatosis, pseuodsarcomatous, fibromatosis
- benign non-neoplastic lesions arising fromt he SQ fascia and superficial portions of the deep fascia in dogs
- Histo: large plump or spindle shaped fibroblast in a stroll network of variable amounts of collagen/reticular fibers
- can be misdiagnosed as fibrosarcomas
- Do not met, local recurrence possible following wide resection
STS grade I
- Differentiation: resembles normal adult mesenchymal tissue
- Mitosis: 0-9/10hpf
- Necrosis: none
cumaltive score </=4 for 3 categories
What is assessed when grading STS?
differentiation, mitosis, necrosis
STS grade II
- Differentiation: specific histologic subtype
- Mitosis: 10-19/10 hpf
- Necrosis: <50%
cumulative score 5-6
STS grade III
- Differentiation: undifferentiated
- Mitosis: >20/10 hpf
- Necrosis: >50%
cumulative score >/=7
Fibrosarcoma: cell type, histo features, IHC
- fibroblast/fibrocyte
- interwoven bundles, herring bone pattern, pronounced collagen stroma
- no IHC
Myxosarcoma: cell type, histo features, IHC
- fibroblast/fibrocyte
- stallate or spindle shaped cells in mucinous stroma
- no IHC
Pleomorphic sarcoma (malignant fibrous histiocytoma): cell type, histo features, IHC
- primitive mesenchymal cells (fibroblasts or myofibroblast)
- mix of fibroblastic cell and karyomegalic, multinucleate historic cells
- IHC +: lysozyme 29-100%, MCH II 70%, desmin 86%, viment
- IHC - : S-100, CD18
Perivascular wall tumo: cell type, histo features, IHC
- pericyte, myopericye, smooth myocyte
- vascular growth pattern
- IHC+: calponis, pan actin, smooth muscle actin 50%
-IHC-: S-100, NSE, GFAP, myoglobin
Peripheral nerve sheath tumor: cell type, histo features, IHC
- Schwann cell, neurofibroblast
- bundles and whorls around collagen bundles, Antoni A and B
- IHC+: NSE 45-82%, S-100 50-100%, neuofilament 82%, NGFR 47%, myoglobin 64%, GFAP 0-35%
Liposarcoma: cell type, histo features, IHC
- lipoblast, lipocyte
- polygonal cells with vacuolated cytoplasm
- IHC+: MDM2 67-75%. CDK4 (variable)
Rhabdomyosarcoma: cell type, histo features, IHC
- skeletal muscle myoblast, skeletal myocyte
- cytoplasmic striation, racket and strap cells
- IHC+: desmin, S-100 75%, NSE 50%, GFAP 50%
Lymphangiosarcoma: cell type, histo features, IHC
- lymph tissue no cell type given
- irregular vascular channels with single layer of plump spine cells and no RBCs
- IHC+ PROX-1 80-88%, Factor VIII related Ag 100%, LYVE-1 80%
Mesenchymoma: cell type, histo features, IHC
- multiple cell types
- multiple soft tissue mesenchyme components
- no IHC
Differentials for S-100 positive STS?
peripheral nerve sheath tumor, rhabomysoarcoma
Signalment differences for fibrosarcomas?
- Younger dogs than any other subtype
- oral location possible
Behavior of fibrosarcomas?
- very likely to recur after incomplete excision
- can have high MC but be low grade (HiLo)
Breeds pleomorphic sarcomas or malignant fibrous histiocytoma?
Flat coated retrievers, Rotties, goldens
Characteristic IHC for malignant fibrous histiocytomas?
vimentin +, CD18 -
Aggressive subtype malignant fibrous histiocytoma?
Giant cell pleomorphic tumors
- highly metastatic to SQ, LN, liver, lungs
- MST 61 days
Most common location of myxosarcomas?
- SQ of trunk and limbs but reports from heart, eye, and brain
Perivascular wall tumors can comprise various components of the vascular wall EXCEPT?
endothelial lining - this is HSA
How are perivascular wall tumors diagnosed/differentiated?
vascular growth patters (e.g. staghorn, planetoid, perivascular whirling, bundles of media)
Behavior of perivascular wall tumors?
less aggressive with low rates of local recurrence
Peripheral nerve sheath tumors of macroscopic nerves classification?
- peripheral, root, or plexus
- not considered part of STS of microscopic nerves
- neuro signs
- root or plexus worse prognosis since less ammenable to SX
MST dogs with brachial plexus peripheral nerve sheet tumor treated with limb sparing compartmental resection?
- MST 1303 d (43 mo, ~3.5 yr)
- completeness of excision prognostic: incomplete 487 d (16 mo) vs 2227d (74 mo)
PFS and OST dogs with brachial plexus tumors treated with SRT?
- PFS 240d (8 mo)
- OST 371d (12 mo)
- local progression reported 90% eventually
- dogs die of local disease before mets
Morphologic subtypes of lipomas?
- regular
- infiltrative
- intermuscular
Histo differentiation of lipoma vs liposarcoma?
lipoma- indistinct nuclei and cytoplasm resembling normal fat
liposarcoma- increased cellularity, distinct nuclei, abundant cytoplasm with one or more droplets of fat
Most common location for inter muscular lipomas?
caudal thigh of dogs between semitendinosus and semembranosus
Biologic behavior of inter muscular lipomas?
slow growing, firm, fixed, local recurrence rare after resection
Composition of infiltrative lipomas?
- well differentiated adipose cells without evidence of anaplasia
- cannot be differentiated by cytology or histo from lipomas
- distinguished only by invasiveness to other tissues - CLINICAL DIAGNOSIS
Signalment predisposition infiltrative lipomas?
4:1 female to male ratio
Treatment infiltrative lipomas?
Aggressive surge usually with amputation +/- RT
Biologic behavior of liposarcomas
- locally aggressive with low metastatic rates
- reports to lungs, liver, spleen, and bone
- bone, spleen, and abdominal cavity can also be PRIMARY
How are liposarcomas differentiated from lipomas?
- morphologic appearance
- cyto: OIL RED O to stain lipid
- CT: mixed-attenuating, heterogenous, multi nodular, contrast enhancing masses on PREcontrast CT
Prognosis liposarcoma with surgery?
- wide resection: 1188d (40 mo)
- sig different from marginal 649d (21 mo) or incisional BX (183d)
Histologic subtypes of liposarcomas in people?
- well differentiated, myxoid, round cell, pleomorphic, dedifferentiated
- pleomorphic highly metastatic
*not prognostic in dogs but one study showed metastasis more common with pleomorphic
Revised classification scheme for liposarcomas?
- based on IHC expression MDM2 and CDK4
- Ki67 higher in dedifferentiated than well differentiated
locations of rhabdomyosarcomas?
urinary bladder, retrobulbar musculature, larynx, tongue, myocardium
- locally invasive with low to moderate metastasis to lungs, liver, spleen, kidneys, and adrenals
How are rhabdomyosarcomas classified?
Histologically: embryonic, botryoid, alveolar, and pleomorphic
Rhambomyosarcoma IHC markers?
vimentin, skeletal muscle actin, myoglobin, myogenic, myogenic differfentiation
desmin s-100
Common location of embryonic rhabdo?
head and neck
Common location of botryoid rhabdo?
- urinary bladder of young, female, large breed dogs with St. Bernards over represented
- grape like appearance
Rhabdo metastatic rate based on subtype?
- botyroid 27%
- embryonal and alveolar 50%
- mets more common in dogs < 2 years of age
- in one study all dogs under 4 died of mets or local disease MST 2.5 mo
- no dogs over 4 died d/t tumor
Clinical signs of lymphangiosarcoma?
Usually soft, cystic like, and edematous.
Extensive edema and drainage of lymph through the skin or mass, non healing, discharging wounds
How can you differentiated lyphangiosarcoma from HSA with IHC?
- both CD31 and factor VIII ag +
- lymph LYVE-1 and PROX-1 positive
Prognosis lymphangiosarcomas?
- 3 dogs no treatment MST 168 (range 60-876; 2 - 30 mo)
- 5 dogs with alone MST 487d (range 240-941d; 8-31 mo)
- 2 SX, RT, and chemo MST 574d
- all dogs eventually died d/t tumor (recurrent or PD locally)
Splenic mesenchymoma reported - MST
- better than other types of splenic sarcomas
- MST 12 mo with 50% 1 year survival
Cytologic accuracy of correctly diagnosing STS?
63-97%
- always submit! disproportionate number of FALSE-NEGATIVE cytologic results associated with in-house assessment
Biopsy methods for STS?
- Can do core, punch, incisional or excisional BUT 41% not excision will differ in grade from definitive sample
- histologic grade UNDERESTIMATED in 29%
- OVERESTIMATED in 12%
Why is excisional biopsy not preferred for STS?
- may not be curative increasing morbidity and cost
- multiple attempts at resection before definitive therapy have negative effect on survival time
REFER
When should LN assessment be performed when staging STS?
- if enlarged, known to be grade III, or suspect nonconlvential type
Minimum recommended surgical margins STS?
2-3 cm lateral and 1 fascial plane deep
Alternative margin system for STS?
- proportional similar to MCT
- larger tumors significantly more likely to recur
Likelihood of STS recurrence with incomplete margins compared to wide resection?
10.5x higher
When might marginal excision be okay for STS?
- well circumscribed, non-infiltrative, <5 cm in diameter, located on limbs below the elbow/stifly
STS recurrence rates following incomplete excision based on grade?
I: 7% - 11%
II: 34%
III: 75% (3 of 4 dogs)
Peripheral nerve sheath tumor recurrence rates?
18-20%
- even with 60% being incompletely excised
- size associated with recurrence, 7x more likely if >5 cm diameter
- increasing risk 1.3x for every 1 cm
Recurrence risk STS based on grade?
5.8 fold if grade III compared to grade I & II
When might active surveillance be an appropriate treatment for incompletely excised STS?
grade I +/- II, well circumscribed, <5cm, distal limbs
further treatment may be unnecessary in up to 93% of dogs with incomplete excised grade I tumors
STS surgical scar revised with 0.5 o 3.5 cm lateral margins - frequency of residual disease identified?
22%
Local recurrence rate for intralesional bleomycin electrochemotherapy for incompletely excised STS?
- 36%
- mean time 730d (~24 mo)
- wound dehiscence in 14%
Local recurrence rate, DFI, 1- 2- 3- year disease free rate STS treated with surgery alone?
RR: wide 0-5%, marginal 11-29%
DFI: 368d to not reached
1 yr: 89-93%
2 yr: 78-82%
3 yr: 66-76%
Local recurrence rate, DFI, 1- 2- 3- year disease free rate STS treated with surgery and fractionated RT?
RR: 17-39%
DFI: 421d to not reached
1 yr: 71-84%
2 yr: 60-81%
3 yr: 57-81%
Local recurrence rate, DFI, 1- 2- 3- year disease free rate STS treated with surgery and hypo fractionated RT?
RR: 18-21%
DFI: 698d to not reached
1 yr: 81%
2 yr: 73%
3 yr: 73%
Local recurrence rate, DFI, 1- 2- 3- year disease free rate STS treated with marginal excision and electrochemotherapy?
RR: 17-31% (higher for grade III)
DFI: 264d to not reached
1 yr: 81-100%
2 yr:69-89%
3 yr: 69-84%
What is the earliest RT should be considered follow STS resection?
7 days to limit AE
- other weird study found that waiting at least 4 weeks to start hypo fractionated RT improved survival
Recommended RT for STS?
- full course, fractionated schedule
- optimal not defined but should be >50 Gy total
- better local control associated with higher cumulative doses
MST for incompletely excised STS (non oral) treated with fractionated RT?
MST 2270 d (75 mo)
1 yr 80-87%
2 yr 72-87%
3 yr 92%
5 yr 76%
What histologic findings in STS has been associated with recurrence when treated with RT?
MC > 9/10 hpf
Recurrence rate of STS to hypo fractionated RT (24-36 Gy) following incomplete or close resection?
18-21% - majority small ~ 3-4 cm, and low grade I -II (83%)
What should you consider when treating STS with hypo fractionated protocols?
patient age/expected survival time - risk of late toxicity increases if living long
PSF and likelihood to be tumor free following hypoRT for incompletely resected STS?
PFS: 698d (23 mo) - not reached
1 yr - 81%
2 yr -73%
3 yr - 73%
Prognosis for STS incompletely excised treated with hypofractionated RT to scar based on grade?
I:
- PFS 1904 d (63 mo)
- OST not reached
II:
- PFS 582d (~20 mo)
- OST not reached
III:
- PFS 292d (~10 mo)
- OST 940d (31 mo)
RT for gross STS tumor control rates?
- dose >50 Gy
- 1 yr 50%
- 2 yr 33%
Hypofractionated RT for gross STS
- 20-36 Gy
- ORR 46-50% (many SD)
- PFI 155-419 d (5-14 mo)
- prognostic factors: tumor location (better for limb 466d vs 110d) and previous surgery (more than 1 did worse 105d vs 420d)
- MST 206-513 d (~7-17 mo)
- MC used in this study did not improve PFI but did MST (757d vs 518d)
When can RT be considered preop for STS?
1) radiation field is smaller because, after surgery, the entire surgical site must be included in the field plus normal tissue margin
2) a larger number of peripheral tumor cells are inactivated with reduced contamination at surgery site
3) tumor volume reduction may make surgical resection less difficult
- lower doses recommended <50 Gy, wound healing may be harder (is in human med)
Metastatic rates for STS based on grade?
I: 0-13%
II: 7-27%
III 22-44%
Median time for metastasis STS?
365 d
MTD chemo protocols for STS?
- DOX
- DOX alternating ifosfamide
- neither shown to improve survival in dogs with grade III STS
How does MC work for STS? Dose?
- inhibiting tumor angiogenesis and suppressing regulatory T cells
- shown at 15 mg/m2/d but NOT 12.5 mg/m2/d
cyclophosphamide
Wound complication rate following intralesional chemotherapy for STS?
47-84%
Poor prognostic factors for local tumor control for STS?
large tumor >5 cm, infiltrative tumors. tumor in locations other than distal limbs, high grade, incomplete margins
What is the median post STS recurrence for dogs who are euthanized due to their tumors?
- 256 days (8.5 mo) vs 945 days (31 mo) median post recurrence for those who died of other caused
- importance of wide resection
Proliferative markers associated with STS survival?
AgNOR - increased 77 times more likely to die as a result of disease
ki 67- increased 12 times more likely to die from disease
You perform an FNA of a mass that is consistent with STS what are the next steps?
biopsy, chest rads, +/- referral
Incompletely excised STS grade II and owner cannot afford definitive RT. What is the recurrence rate? Alternative treatment options?
- recurrence <10%
- MC, hypo fractionated RT, electrochemotherapy, monitor
What is the survival time STS with >20MI, 10-19MI, <10MI in STS?
> 20 MST 236days (8 mo)
10-19 MST532 (18 mo)
<10 MST 1444 (48 mo)