Melanoma Flashcards
Who gets melanoma?
Common is dogs with skin pigmentation, rare in cats
What are the 9 common location for melanoma?
Haired skin, oral cavity, nailbed, footpad, eye, GI tract, nasal cavity, anal sac, or mucocutaneous junction.
5 common sites of metastasis for melanoma?
LNs, lungs, liver, meninges, and adrenal glands
Etiology of melanoma in dogs? In humans?
Etiology in dogs in not established. In humans, cutaneous melanomas arises from exposure to UV light.
Melanoma is the most common oral malignancy, T/F?
True
5 dog breeds commonly affected by melanoma?
Scottish terriers, golden retrievers, Chow Chows, poodles, and daschunds
Found in the following 4 locations in the mouth by order of decreasing frequency?
gingiva, lips, tongue, hard palate
Feline melanoma is rare but malignant in most cases, T/F?
True
Melanoma can masquerade like what tumor?
4 IHC markers useful for diagnosing melanoma?
STS
PNL2 and tyrosinase in addition to Melan A and S-100.
BRAF mutation is common in OMM, T/F?
False
BRAF, member of MAPK signaling pathway that is commonly mutated in human cutaneous melanoma but not in oral human melanomas.
Transcriptome analysis has uncovered new therapeutic targets in canine melanomas
The melanoma-associated genes clustered in the areas of focal adhesion and PI3k-Akt signaling pathways, extracellular matrix-receptor interactions, and protein digestion and absorption.
Small subset have exon 11 c-kit gene mutation, therefore use of KIT small molecule inhibitors (particularly in dogs with advanced stage of disease and/or lack of response to Oncept) should be considered.
Somatic mutations in NRAS and PTEN can be found in canine MM and may represent therapeutic targets in future.
Biologic behaivour of melanoma is based on what 4 factors?
Biologic behavior is variable and based on anatomic site, size, stage, and histologic parameters
Behaivour of haired skin melanomas?
Treatment?
Additional diagnostic to help predict malignancy potential in cutaneous melanoma?
Haired skin melanomas that are not in proximity to mucosal margins behave in benign manner.
Surgical excision is curative but interpret margins and cytologic features.
Ki67 IHC has been reported to reliably predict potential malignant behavior for cutaneous melanoma.
Dogs with digit melanoma without LN or distant metastasis treated with digit amputation have MST of?
Metastasis at time of presentation is seen in?
Prognosis for dogs with melanoma of the foot pad has been reported, however Bergman has found this anatomic site to be similar in metastatic potential and prognosis to digit melanoma
12 months with 1- and 2- year survival rates of 42% to 57% and 11% and 13%
30% to 40% of dogs.
Majority of dogs will develop regional or distant metastatic disease
What is prognostic in oral melanoma in dogs and what is the WHO staging system?
Stage I
Stage II
Stage III
Stage IV
Tumor size
WHO staging scheme is based on local tumor size, regional and distant metastasis
Stage I (<2 cm diameter): nonmetastatic tumor
Stage II (2-4 cm): nonmetastatic tumor
Stage III (>4 cm and local LN metastasis)
Stage IV (distant metastasis)
MST for dogs with oral melanoma treated with surgery are:
Stage I
Stage II
Stage III
Stage I: 511 to 874 days (1.4 years - 2.4years)
Stage II: 160 to 818 days (5 - 27 months)
Stage III: 168 to 207 days (5.6 - 6.9 months)
Recent study suggests dogs with stage I oral melanoma treated with standardized therapies including surgery, RT and/or chemotherapy have MST of?
Most dogs die from?
12 to 14 months with most dogs dying from distant metastasis and not local recurrence.
LN should not be sampled if lymphadenomagaly is not present, T/F?
LN metastasis can be present in __ of dogs with lymphadenomagaly and ___ in normal sized LNs?
False - should always be sampled
70%, 40%
Most effective treatment option for melanoma?
Wide surgical resection with 2-3 cm margins
Melanoma is ____ tumor requiring a _____ dose in each fraction for local control.
Radioresistant, higher
Relative radiosensitivity of melanoma in animals has not been determined and nor has ideal dose per fraction in hypofractionated protocols.
Partial response and complete response to RT are ____ and ____ with overall response rate of ____.
PFS ranges?
25% to 67%
19% to 69%
82% and 94%
PFS ranges from 3.6 to 8.6 months.
MST for dogs treated with RT?
MST for dogs treated with RT range from 4.5 to 14.7 months
Study with 39 dogs with incompletely excised oral melanoma treated with either cisplatin or carboplatin once weekly approximately 1 hr before receiving RT (6 weekly x 6 Gy)
Local recurrence reported in ____ median time to metastasis was ___ months, MST was ____ months.
15% dogs,
10.2 months
MST 11.9 months
Prospective study with 27 dogs with malignant melanoma of oral and nonoral sites, 15 dogs treated with RT (5 fractions of 6 Gy over 2.5 weeks) alone and 12 dogs with RT and temozolomide (60 mg/m2 PO for 5 consecutive days).
Overall response rates for both groups was?
Median time to progression was longer in dogs treated with RT and temozolomide was ___ vs. ___ for RT alone
MST was not significantly different (RT alone 192 days and 402 days for RT and temozolomide).
86.7% and 81.1%
205 days versus 110 days for RT alone