A 60 year old male had a chronic history of exposure of asbestosis. He now presents with a mass in the apex of right lung. Which of the following would be seen on electron microscopy of a biopsy from the lesion?
Ans. (c) Numerous long slender microvilli(Ref: Robbins 9th/pg 723-724; 8th/pg 733-734)Prolonged asbestos exposure increases the risk of mesothelioma, which presents as a localized gray-white pleural mass.FeaturesAdenocarcinomaMalignant MesotheliomaImmunohistochemistryCarcinoembryonic antigen (CEA), CD15, Ber-EP4, MUC4, thyroid transcription factor 1 (TTF-1), Napsin ACalretinin, WT1, keratin 5/6, claudin-4,thrombomodulin, D2-40/podoplanin, h-caldesmon, caveolin-1, vimentinElectron microscopyShort & plump microvillilonger and more slender microvillAbout other options,A. Melanosomes: Seen in Malignant MelanomaB. Neurosecretory granules: Seen in Small Cell Carcinoma of lungD. Desmosomes with secretory endoplasmic reticulum: can suggest Adenocarcinoma
Melanosomes
Neurosecretory granules
Numerous long slender microvilli
Desmosomes with secretory endoplasmic reticulum
Respiration