Skin and Soft Tissue Flashcards
risk factors for melanoma
dysplastic/atypical congenital levi (10% lifetime risk for melanoma), familial BK mole syndrome 100% lifetime risk, xeroderma pigmentosum, 10% are familial; fair complexion, easy sunburn, intermittent sunburns, previous skin Ca, previous XRT
where are melanocytes from?
neural crest cells in basal layer of epidermis
most common location for distant melanoma metastasis
lung
most common metastasis to small bowel
melanoma
most common type of melanoma? most aggressive?
most common type is superficial spreading melanoma, most aggressive is nodular
recommended margins for melanoma?
in situ 0.5-1cm, <1 mm = 1 cm, 1-2mm = 1-2 cm margins, >2mm = 2 cm margins
what is the difference between an in transit lesion and satellite?
intransit lesions are > 2 cm from primary lesion but not beyond the nodal basin, satellite lesions are <2 cm
what are the boundaries of a pelvic lymph node dissection
superiorly inguinal ligament, medially the fem vessels and adductor longus, laterally sartorius, inferiorly the adductor hiatus
indication for SLNBx in melanoma?
for all melanoma >1mm deep or with overlying ulceration regardless of depth
what is an important step for all anterior head/neck melanomas >1mm deep?
superficial parotidectomy
most common malignancy in the US?
basal cell ca; 4x more common than squamous cell ca
skin bx shows peripheral palisading nuclei and stromal reaction
basal cell ca
most common soft tissue sarcoma
malignant fibrous histiosarcoma»_space; liposarcoma
staging of sarcoma is based on…?
grade
what chemo agents used in sarcoma?
doxorubicin based
most common soft tissue sarcoma in children? most common type? worst prognosis?
rhabdomyosarcoma; most common type is embryonal (has good prognosis), worst prognosis is the alveolar type
CNS tumors, peripheral sheath tumors, pheochromocytoma
neurofibromatosis
merkel cell carcinoma: features and tx
rare neuroendocrine skin ca, pink nodule that progresses to blue color w/ or w/o ulceration, occurs in elderly light skinned pt w/ sun exposure or immunosuppression: AEIOU - asymptomatic, expanding rapidly, immunosuppression, over 50, UV exposed area – Merkel cell polyomavirus, WLE with 1-2 cm negative margins + SLNBx and adjuvant XRT
most common location of a desmoid tumor
anterior abdominal wall
Bowen’s disease?
SCCA in situ of perianal margin, 10% turn to invasive SCCA, associated with HPV 16 and 18, tx w/ Imiquimod, cautery ablation, topical 5FU, avoid WLE
lab value used in melanoma staging?
LDH
most common cutaneous soft tissue sarcomas? #1? #2?
Kaposi sarcoma > dermatofibrosarcoma protuberans (DFSP)
result of the MSLT-1 trial
no survival benefit in patients w/ positive SLNBx who underwent completion lymphadenectomy vs observation
slow growing soft tissue mass subscapular/infrascapular region: dx, imaging findings, tx
elastofibroma dorsi, MRI shows mass w/ streaks of fibrous and fatty tissue located beneath scapula; symptomatic pt undergo simple excision (otherwise observe, no malig potential)
