Surgical Pathology Unknown Conference for the Web
Case 1
Clinical History
This patient presented with splenomegaly
Choose the Correct Diagnosis
A.
B.
C.
D.
Mycobacterium avium intracellulare
Gaucher disease
Whipple disease
Glycogen storage disease type V
Histology
The normal constituents of the spleen are extensively replaced by cells with abundant
pale somewhat granular cytoplasm. A Ziehl-Neelsen stain for acid fast bacilli and
immunostains for the organism that causes Whipple disease (Tropheryma whippelii) were
negative.
Discussion
Gaucher disease is an autosomal recessive disorder caused by inherited mutations in the
gene for glucocerebrosidase. Glucocerebrosidase normally functions to remove a glucose
from ceramide. Loss of glucocerebrosidase function in turn leads to the accumulation of
glucocerebroside in phagocytic cells in the spleen, liver and bone marrow, lymph nodes,
and other organs. The central nervous system is rarely involved (called type II when there
is CNS involvement).
By light microscopy, the Gaucher cells have abundant vacuolated cytoplasm with a
“tissue paper” appearance.
Case 2
Clinical History
This elderly patient presented with diarrhea.
Choose the Correct Diagnosis
A.
B.
C.
D.
Carcinoid tumor with secondary lymphatic obstruction
Adenocarcinoma with secondary lymphatic obstruction
Lymphangiomatosis
Lymphangiosarcoma
Histology
Two processes are seen. The first is a widely disseminated well-differentiated neoplasm
with lymphatic invasion. The second is dilation of the lymphatics in the bowel.
Discussion
This is a dramatic case of a carcinoid tumor extensively involving the lymphatics of the
bowel with secondary lymphostasis. Microscopically, carcinoid tumors are characterized
by nests of well-differentiated cells with uniform round nuclei. The nuclei have a “salt
and pepper” chromatin pattern. Small bowel carcinoids less than 2 cm without
angioinvasion are generally benign, but, as demonstrated in this case, those > 2 cm and
those with angioinvasion can follow a malignant course.
Case 3
Clinical History
This 43 year old presented with weight loss.
Choose the Correct Diagnosis
A.
B.
C.
D.
E.
Cryptosporidiosis
Microsporidiosis
Giardia
Strongyloides
Entamoeba
Histology
Numerous parasites are seen in this biopsy of the gastrointestinal tract.
Discussion
Helininths can cause a variety of diseases in humans. Helminths have complex life cycles,
although most adult worms do not multiphy in humans. Strongyloides is an exception to
this as autoinfection can occur. Strongyloidiasis occurs primarily in tropical and temperate
climates. The free-living adult female measures 1 mm and the parasitic female 2-3 mm in
length. Eggs measures 50 to 60 microns in length. Adult female worms inhabit the crypts
of the small intestine. It is there that the females deposit eggs.
Reference: Pathology of Tropical and Extraordinary Disease, C.H. Binford and D.H.
Conner, Armed Forces Institute of Pathology.
Case 4
Clinical History
This middle aged person presented with a supraclavicular mass.
Choose the Correct Diagnosis
A.
B.
C.
D.
E.
Ectopic hamartomatous thymoma
Metastatic breast carcinoma
Metastatic prostate cancer
Mesothelioma
Synovial sarcoma
Histology
This well-circumscribed lesion is composed of short fascicles of histologically bland
spindle-shaped cells, epithelial cells forming anastomosing cords, and a small amount of
fat.
Discussion
Ectopic hamartomatous thymoma is a rare benign neoplasm composed of a mixture of
epithelial cells, spindle-shaped cells and fat. This lesion can occur in the supraclavicular
area and the lesions typically contain CD99 positive lymphocytes, and the spindle cells
express CD10 and alpha-smooth muscle actin.
References: Lee, SN, et al. Ectopic hamartomatous thymoma: a case report showing
CD99 lymphocytes and a low proliferation index. Arch Pathol Lab Med. 2003; 127:37881.
Fukunaga M. Ectopic hamartomatous thymoma: a case report with immunohistochemical
and ultrastructural studies. APMIS. 2002; 110:565-570.
Case 5
Clinical History
This immunocompromised patient presented with diarrhea.
Choose the Correct Diagnosis
A.
B.
C.
D.
Mycobacterium avium intracellulare
Gaucher disease
Whipple disease
Glycogen storage disease type V
Histology
Numerous foamy macrophages are present within the lamina propria of this biopsy. A
Ziehl-Neelsen stain revealed numerous acid fast organisms.
Discussion
This is a straightforward case of mycobacterium avium-intracellulare complex (MAI)
involving the gut. I put it on to contrast with Case #1, the case of Gaucher disease. Note
the differences in the appearance of the foam cells on hematoxylin and eosin staining. In
Gaucher disease, the foam cells have a “tissue paper” appearance, while in MAI the
cytoplasm is more granular. Special stains are needed to establish the diagnosis.
Case 6
Clinical History
This elderly man presented with a mass in the head of the pancreas.
Choose the Correct Diagnosis
A.
B.
C.
D.
E.
Pancreatic intraepithelial neoplasia-1
Pancreatic intraepithelial neoplasia-2
Pancreatic intraepithelial neoplasia-3
Infiltrating adenocarcinoma
Intraductal papillary mucinous neoplasm
Histology
The lesion highlighted is composed of a well-differentiated glandular epithelium with
minimal atypia. While it could represent a low-grade PanIN, the VVG stain reveals that
these epithelial cells are within a blood vessel.
Discussion
Invasive adenocarcinoma of the pancreas, in addition to invading nerves, often invades
blood vessels. When they do they can form a tumor thrombus or the neoplastic cells can
line the wall of the blood vessel. This latter pattern can be very striking, with the
neoplastic cells appearing to replace the endothelial cells. This pattern of vascular
involvement is important to recognize because it can mimic a PanIN lesion or an IPMN.