APCON 2010 Hyderabad
NATIONAL PATHOLOGY QUIZ – 2
Answers
Q 9: Jackalope. Mythical creature; stories inspired by rabbits infected with Shope papilloma virus.
Rabbits with antlers is a myth prevalent in Europe and North America from medieval times. Computer geeks would recognize it as the mascot of the free software Ubuntu 9.04, codenamed ‘Jaunty Jackalope’.
The myth was probably inspired by sightings of rabbits infected with the cottontail rabbit papilloma virus (CRPV) made familiar to pathologists by Richard Shope.
Shope begins his famous article of 1933 – the first demonstration of a transmissible tumor in mammals – thus. “Our attention was recently called to a disease occurring in wild cottontail rabbits in northwestern Iowa. Rabbits shot there by hunters were said to have numerous horn-like protuberances on the skin over various parts of their bodies. The animals were referred to popularly as "horned" or "warty" rabbits.”
R
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Shope is a great figure in the history of medicine. This is what
Peyton Rous – another pioneer – had to say while presenting him
with the New York Academy medal.
“Thus did Dr. Shope begin the huge task at which he has toiled ever since: to find and control the virus diseases of animals. He has dealt not only with diseases of the farm but of wild creatures as well. Within two years after his work on influenza he found in the cottontail rabbits of the Southwest the first virus causing tumors in a mammal. This discovery still resounds, as bearing directly on the cancer problem. For the virus not only induces and actuates benign tumors of the epidermis,but it initiates carcinomas that originate from the cells of these growths. The parallel with the consecutive neoplastic changes occurring in certain human instances of cancer is complete.”
Correct answers: 53.7%
Links
1. Full text of 1933 article by Richard Shope
2. Richard E Shope – short biography
Q 10: Laryngeal edema in systemic anaphylaxis
Respiratory epithelium with mucous glands and cartilage. The subepithelial tissue is edematous; you can see the pale pink edema fluid best in the third picture. Eosinophils predominate the inflammatory infiltrate. As a cause of death, this can only be laryngeal edema in a systemic anaphylactic reaction. As a matter of fact, this was a case of fatal drug reaction.
Some of you have given acute asthma or status asthmaticus as the answer. I agree that histologically the two conditions can be very similar and of course one may be forgiven for thinking that the section is from the lower respiratory tract. So, full credit is given for this response as well.
Correct answers: 52.1%
Links
1. Autopsy findings in systemic anaphylaxis
Q 11: Cavernous hemangioma, liver
In retrospect, it seems that recognition of the organ as liver is difficult; though I thought liver tissue was discernable at the periphery.
It is a fairly well defined mass lesion with a fibrous demarcation. There are spaces of varying sizes from very tiny to much larger ones, all filled with dark reddish brown material. The larger spaces are surrounded by fibrosis.
Melanoma mets have been suggested by some. These would be of a much blacker hue and would be discrete nodules separated by normal liver tissue without fibrosis.
In peliosis hepatis, the blood-filled cavities or cysts (0.2 to 5cm) do not have any particular zonal distribution within liver parenchyma and so would not be seen as a mass lesion. Rare cases of focal peliosis with pseudotumoral appearance have been described. I suppose, in such rare cases, the gross appearance could be similar.
Correct answers: 10.1%
Links
Q 12: Glucagonoma syndrome
The skin lesion is quite characteristic when seen in context. They are scaly, erythematous and hyperpigmented. The biopsy shows parakeratosis and necrosis of the superficial layers of the epidermis with intact deeper layers.
The MRI shows a contrast enhancing lesion of the tail of pancreas (arrow). The excised tumor along with the spleen is seen in the next picture. The histology depicts a typical neuroendocrine tumor having trabecular and sinusoidal patterns.
This patient was diabetic and had stomatitis and glossitis, features highly suggestive of glucagonoma.
The skin biopsy of ‘Necrolytic migratory erythema’ shows mainly involvement of superficial layers of the epidermis. The cells become vacuolated and the nuclei pyknotic. Later the upper layers become necrotic. Similar appearance can be seen in pellagra and zinc deficiency; but seen in the proper setting there can be no mistake.
Correct answers: 55.3%
Links
1. Necrolytic migratory erythema
Q 13: Adrenal medulla. Sustentacular cells stained with S-100
Large cells clustered together in a nesting pattern, surrounded by positively stained flattened cells arranged in a circumferential manner. Paraganglia will have an identical appearance.
Many of you thought they were endothelial cells in the liver. But hepatocytes would have a trabecular rather than nested arrangement. The endothelial cells lining sinusoids would not be curved and arranged in this pattern.
Correct answers: 38.3%
Links:
1. Histogenesis of adrenal medulla
Q 14: Superficial spreading melanoma with regressive changes
Lesion on the skin of the breast occupying a wide area. The color is blackish interspersed with hypopigmentation.
Being the breast, the immediate reaction on seeing the histology is to say ‘Ah! Paget’s’. But that diagnosis would not explain the black and white speckled lesion. Nor would it account for the intense inflammation and prominent telengectasia in the sub-epidermal region.
The routine IHC stains the epidermal cells but not the large tumor cells. It is cytokeratin cocktail. Some have postulated it being different CK subtypes; but those would hardly be called routine!
The intense inflammation, telengectasia and hypopigmentation are regressive changes similar to those seen in halo nevi.
Correct answers: 14.9%
Links:
1. Primary cutaneous melanoma of breast
2. Histologic criteria for cutaneous malignant melanoma
Q 15: Sickled erythrocytes in the inter-villous space of placenta. The red cells within villi are normal.
The tissue can be recognized as placenta by the syncytiotrophoblast (dark aggregated nuclei) and the inter-villous spaces containing red cells. Almost all the erythrocytes in the inter-villous spaces are sickled, in great contrast to those lying within the villi. The maternal red cells are sickling, indicating that the mother is either homozygote or heterozygote for HbS. The baby’s status would be unknown since the erythrocytes would not sickle - whatever the genotype – due to the high content of HbF.
Correct answers: 54.3%
Links:
1. Placenta in sickle cell disease
Q 16: Lupus panniculitis (Lupus profundus)
The histology can be summarized as a panniculitis with intense lymphoid infiltration and lymphoid follicles with germinal centers. Lipophagic giant cells seen are secondary to the panniculitis and fat destruction.
The most common answer was ‘subcutaneous panniculitis like T cell lymphoma’. But, there is no hemophagocytosis and no atypical lymphoid cells are seen. Moreover, lymphoid follicles – well seen in the H&E and CD-20 stained slides – are not a feature of this condition. Lymphoid follicles with germinal centers in a setting of panniculitis is virtually diagnostic of Lupus erythematosis.
Lupus profundus may appear in patients with discoid lupus erythematosus and systemic lupus erythematosus, but also as the unique manifestation of lupus erythematosus, and in such cases the diagnosis may be problematic. In this patient, the serological profile was diagnostic of SLE.
Correct answers: 19.1%
Links: