Pathology Notes

Practice question answers, skin tumors 2 © Jun Wang, MD, PhD 1. A. Dysplasia limited to basal layer is most consistent with actinic keratosis . Basal cell carcinoma has irregular budding, nest, cords of basaloid cells with scant cytoplasm with peripheral palisading. Bowen disease has full thickness dysplasia. Dermatophytosis is fungal infection and has intraepidermal neutrophilic infiltration but not keratinocytic atypia. Melanoma in situ has Pagetoid spread of atypical melanocytes. 2. E. Actinic keratosis is a squamous precancerous lesion and may develop into squamous cell carcinoma or basal cell carcinoma . 3. E. This lesion has irregular nest, cords of basaloid cells with scant cytoplasm with peripheral palisading, characteristic for basal cell carcinoma . The most important carcinogenic factor for melanoma , squamous cell carcinoma or basal cell carcinoma is UV light from sun exposure. Abnormal keratinocytic turnover is seen various lesions, including psoria

Practice questions, skin tumors 2 © Jun Wang, MD, PhD 1. Use this case and this image for the next two questions . A 65-year-old male farmer presents with an incidentally found slightly discolored skin lesion on his forehead. He denies other symptoms. He has a history of multiple squamous cell carcinomas and basal cell carcinomas of skin, all treated with local resections. Physical examination reveals a 2.5 cm slightly erythematous area with a rough surface at his left forehead. No other significant abnormalities are noted. An image of the biopsy is shown. What is the diagnosis? (Image: LWozniak&KWZielinski [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]) A. Actinic keratosis B. Basal cell carcinoma C. Bowen disease D. Dermatophytosis E. Melanoma in situ 2. A 65-year-old male farmer presents with an incidentally found slightly discolored skin lesion on his forehead. He denies other symptoms. He has a history of multiple squamous cell c

Practice question answers, skin tumors 1 © Jun Wang, MD, PhD 1. C. Epidermal proliferation with pseudohorn cysts is most consistent with seborrheic keratosis . Actinic keratosis has dysplasia limited to basal layer, usually not epidermal proliferation or pseudohorn cysts. Merkel cell carcinoma has intradermal sheets of poorly differentiated cells with scant cytoplasm and express neuroendocrine markers such as CD56, synaptophysin and chromogranin. Squamous cell carcinoma has irregular nests or cords of atypical squamous cells with intercellular bridges and/or keratin pearl formation . Verruca vulgaris is caused by human papillomavirus and usually has koilocytes . 2. B. The skin lesion has epidermal proliferation with pseudohorn cysts , most consistent with seborrheic keratosis . Sudden increased number of seborrheic keratosis is suggestive of Leser-Trelat syndrome , associated with internal organ malignancies, especially GI tract. This patient has clinical presentations