Squamous Cell Carcinoma Flashcards
SCC
2nd most common type, can mets, common in light skin, found on sun exposed areas
Risk factors SCC
UV exposure, tanning bed, therapeutic UV exposure for psoriasis, radiation therapy, arsenic exposure, smoking, immunosuppression, fitzpatrick 1&2
Pathogenesis of SCC
Keratinocytes become transformed d/t the mutation of the p53 gene which becomes resistent to cell death and replicates rapidly
Where can it develop
Skin, mouth, esophagus, vagina, anus
Clinical features SCCIS
Erythematous scaly patch
Erythroplasia of Queyrat location
penis
Bowenoid papulosis
genital condyloma a/w HPV 16 & 18
Cutenous horn
horn like projection from skin often on the face with rapid growth
Location
bald scalp, face, neck, dorsal arms and hands, pretibial
Clinical Variants of SCC
1) Pigmented 2) KA 3) Verrucuous with subtypes a) Epithelioma cuniculatium on the plantar foot b) Giant condyloma acuminatum of genitalia (buscke-lowenstein tumor) and c) oral papillomatosus (oral HPV)
Pathology well differentiated v poorly differentiated
well: atypical keratinocytes with nucleus atypia. poorly: no keratinocytes, nucleus atypia, spindle cell morphology
mets risks
tumor thickness > 2mm, diameter > 2cm. locations of ears, lips, penis, vulva, occurence in a prior radiated area, poorly differentiated type, those on immunosuppressives
mets starts with
lymphatics with the organ involvement of lungs or bone
tx SCCIS
Excision, ED&C, 5FU BID X 4-8 weeks or Imiquimod once daily x 4 weeks
tx SCC invasive
radiation when surgery cannot be performed, wide excision 4mm-6mm margins, MOHS is gold standard, refer to onc for mets