16.  A 50 year old woman developed a persistent cough.  A plain-film chest radiograph showed a rounded 5 cm. mass in the anterior mediastinum (top left).  After a fine needle aspiration biopsy was done (top right & bottom left), surgical excision was performed (bottom middle & right).

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Diagnosis = Castleman disease, unicentric hyaline-vascular type.

https://en.wikipedia.org/wiki/Castleman's_disease

https://en.wikipedia.org/wiki/Benjamin_Castleman

17.  A 3 year old Mexican immigrant child was brought to medical attention by his parents, because of a rapidly-enlarging mass in the right orbit.  On physical examination, marked right-sided proptosis was apparent, with suffusion of the surrounding soft tissues.  An orbital exenteration was performed, yielding the specimen shown here.

Diagnosis = Retinoblastoma

https://en.wikipedia.org/wiki/Retinoblastoma

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18. A 78 year old man had had annular patches and plaques over much of his body for 5 years. He now presents with nodular and partially necrotic lesions in the skin of the foot.

Diagnosis = Transformed Mycosis Fungoides, Acral Necrotizing Type

http://bloodjournal.hematologylibrary.org/content/95/7/2212.long

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19. A 41 year old woman was given oral trimethoprim-sulfamethoxazole for a urinary tract infection. Five days later, she developed the cutaneous eruption shown here. The skin biopsy specimen is also illustrated.

Dx = Erythema multiforme

http://en.wikipedia.org/wiki/Erythema_multiforme

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20.   44 year old man with right testicular mass, found preoperatively   to have a serum bHCG level of 500 IU/L.  The clinical suspicion was that a choriocarcinomatous component would be present.

  

Dx = "Pure" Seminoma  Containing Scattered Syncytiotrophoblastic Cells ( a Biochemical Simulant of Choriocarcinoma)


http://en.wikipedia.org/wiki/Seminoma

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