skin malignancies Flashcards
dermatofibrosarcoma have a translocation of which chromosomes?
t (17,22)
whats the most common skin malgnancy in white people?
BCC
70% present on face and head
90% locally invasive only
don’t occur on palm of hand, plantar foot or mucosa
what is the mutation seen in basal cell nevus syndrome (gorlin syndrome)?
germline mutation of the human patched gene 1 (PTCH1)
Major dx criteria: >2 confirmed BCC or 1 bcc <20yrs
keratocystic odontogenic tumors of jaw
>3 palmar and plantar pits
1st degree relative
bimallelar ca of falx cerebri <20yrs
fused, bifid or splayed ribs
multiple BCC few to thousands on face,chest, head flesh colored papules to ulcerating plaques
avoid radiotherapy and sun exposure
deformed w/ macrocephaly, hypertelorism, bifid ribs, palmar and plantar pitting, bone cysts in mandible, flax cerebri calcification, medulloblastoma in demsoplastic subtype 3-5%
what % of BCC have abnormal hedgehog pathway signaling?
90%
hedgehog is targeted in therapy for this reason
What is the surgical margin for BCC <2cm and nonagressive?
4mm
What is the margin for BCC that is >2cm, aggressive, or recurrent?
10mm and CCPDMA + mohs
what does CCPDMA stand for?
complete circumferential peripheral and deep margin assessment
Congenital nevus sebaceous is most likely to transform into what benign neoplasia or malignancy?
Congenital nevus sebaceous
Scalp 60% face 30%
Harmartoma pilosebaceous unit of skin, mutations of the RAS pathway
Associated with HPV transmission from mother to infant
Excise for cosmetic and possible transformation risk
Most common trichoblastoma neoplasia
Most common malignancy is BCC
What margins have the lowest recurrence rate for dermatofibrosarcoma protuberans?
5cm
Using 1-cm margins around the primary tumor leaves residual microscopic tumor in more than 70% of patients, 2-cm margins in 20 to 40% of patients, 3-cm margins in 9 to 15.5% of patients, and 5-cm margins in 5% of patients. Peripheral margins of 5 cm have a close to 0% recurrence rate.
