title: Clinical recognition of actinic keratoses in a high-risk population: how good are we?
abstract: BACKGROUND
  Actinic keratoses (AKs) are dysplastic epidermal lesions considered to be potential precursors of squamous cell carcinoma. Most AKs are diagnosed clinically and are rarely confirmed histologically. High interobserver variation exists among dermatologists for the diagnosis of AKs. Previous studies of the positive predictive value of the diagnosis of AKs have yielded rates as high as 94%. This study evaluates the rate at which histologic analysis confirms the clinical impression (positive predictive value) of AKs in patients with a history of skin cancer.
  
  
  METHODS
  Seventeen (74%) of 23 lesions with classic features of AKs, as determined by 3 dermatologists, were confirmed as AKs histologically. These were lesions that would ordinarily not be biopsied. Of the 6 misdiagnoses, 5 (83%) were skin cancer, most often squamous cell carcinoma.
  
  
  CONCLUSIONS
  The positive predictive value of 74% for the diagnosis of AKs in this study is substantially lower than that of 2 previous studies, suggesting that physicians may be misdiagnosing many patients with classic features of AKs. Most misdiagnosed cases were forms of skin cancer. These preliminary data suggest that the threshold for biopsy of suspect lesions in patients with a history of skin cancer should be low and warrant further evaluation.
authors.affiliation: Department of Dermatology, Dermatologic Surgery, and Pathology, Tufts University School of Medicine, Boston, Mass, USA.
authors.forename: Suraj S
authors.initials: SS
authors.lastname: Venna
authors.forename: Dennis
authors.initials: D
authors.lastname: Lee
authors.forename: Miguel J
authors.initials: MJ
authors.lastname: Stadecker
authors.forename: Gary S
authors.initials: GS
authors.lastname: Rogers
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D001707:Biopsy, Needle; D002280:Basal Cell Carcinoma / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D015994:Incidence; D007642:Keratosis / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery; D008297:Male; D008545:Melanoma / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D010865:Pilot Projects; D011230:Precancerous Conditions / Q000473:pathology*; D011379:Prognosis; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D012878:Skin Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery*