2 Thyroid NoduleNote that the mass is well circumscribed and there is a sharp line of demarcation between the mass and the adjacent thyroid tissue (arrows).
3 High-power view of the border between the tumor mass and adjacent thyroid tissue Note that the mass has compressed the adjacent normal thyroid tissue (arrow). Also note the different morphology between the adenoma (very cellular, dense follicles, little or no colloid) and the adjacent normal thyroid (larger follicles, colloid).
4 Adenoma ThyroidNote the compression of the adjacent normal thyroid and the difference in morphology between the adenoma and the thryoid.
5 Densely packed follicular pattern in the adenoma (left) and the larger colloid-filled follicles of the normal thyroid on the rightAn area of compressed thyroid is present adjacent to the adenoma (arrow).
6 Note that the follicular architecture is well developed and more or less uniform throughout this section of the adenoma.
7 Relatively normal cellular architecture of this follicular adenoma
9 Three ovoid, well-circumscribed nodules surrounded by fibroadipose tissue
10 Higher magnification of one of the three nodules At this power, the nodule seems to be composed of a solid parenchyma with small glandular spaces. The adjacent breast parenchyma consists mostly of fat.
11 FibroadenomaDense stroma of the tumor surrounding the irregularly shaped ductsThe adjacent fibrofatty tissue containing breast ducts and lobules has been compressed by the tumor.
12 Compressed connective tissue (arrow) between two nodules of dense fibrous tissue and ducts
13 FibroadenomaDucts embedded in connective tissue
14 FibroadenomaDense stroma of the tumor surrounding the irregularly shaped ductThe ducts are lined by two cell layers, one of cuboidal, two columnar cells (inner layer), and an outer layer of flattened cells with hyperchromatic nuclei (myoepithelial cells)
15 FibroadenomaIrregularly shaped ducts lined by two cell layers of cells, as previously described
22 Well-differentiated Squamous Cell Carcinoma Note the intracytoplamic keratinization which gives the cells a glassy appearance. The focal accumulations of keratinized cells are called keratin pearls (arrows).
23 Poorly differentiated area of tumor Note the spindle-shaped cells and the irregular pattern of growth.
24 Section of muscle from the lip biopsy Note that the squamous cell carcinoma has infiltrated into the muscle tissue. There are also inflammatory cells within this area of tumor infiltration.
25 Esophagus: Squamous Cell Carcinoma Lab 7, Case 4
26 Luminal surface of esophagus 1: Area of constriction (protrudes into lumen)2: Central area of ulceration
27 Cross-section through esophagus at area of constriction Shows extensive infiltration of the esophageal wall with squamous cell carcinoma (arrows)
28 Normal epithelium undergoing transition to carcinoma (arrows)
29 Invasive squamous cell carcinoma Tongues and islands of tumor cells exhibit areas of central necrosis (arrow).
30 Bands of tumor cells invading into the adjacent tissues (arrows)
31 Bands of tumor cells (arrows) extending between the muscle bundles
32 Tumor cells that have invaded the adjacent muscle tissue
50 Tumor nodule in the lung The tumor cells are infiltrating into the lung parenchyma (1). There is a large area of necrosis in the center of the tumor (2).
51 Edge of the tumor nodule in the lung The tumor cells are infiltrating into the lung parenchyma (1). Even at this power, you can see the glandular formation of this adenocarcinoma. There is a large area of necrosis in the center of the tumor (2).
52 Edge of the tumor nodule in the lung The tumor cells are growing in a glandular pattern. The area of necrosis is evident at the right side of the image.
53 Breast: Infiltrating Ductal Carcinoma Lab 7, Case 7
54 Surgical specimen of breast with infiltrating duct carcinoma Note the tumor tissue under the area of the nipple. The tumor infiltrates in an irregular fashion into the breast parenchyma. Note the nipple retraction caused by this neoplasm.
55 Sections of normal breast (lower) and breast tissue with infiltrating duct carcinoma (upper) Note the increased cellularity (increased blue staining due to the increased number of nuclei) in the tumor tissue.
56 Section of breast with small groups of carcinoma cells throughout the breast tissue and invading through the dermis
57 Abundant groups of tumor cells dissecting through the breast parenchyma Tumor infiltration (infiltrating duct cell carcinoma)
58 Cellular and nuclear features of the tumor cells The large epithelial cells form glands and are medium-sized with a moderate amount of cytoplasm, vesicular nuclei, and nucleoli.
59 Breast tissue with abundant fibrous tissue throughout the tumor (desmoplasia, scirrhous carcinoma)
60 Periphery of tumorBands of tumor cells infiltrating into the fat tissue
61 Growth pattern of the tumor The tumor consists of malignant duct-lining cells growing in cords, solid cell nests, tubules, and glands. The cytologic detail of tumor cells varies from small cells with moderately hyperchromatic, regular nuclei to large cells with large, irregular, hyperchromatic nuclei.
63 Skin with melanomaNote the black pigment, multiple satellite nodules, and focal ulceration. Some of the satellite nodules affect the nipple.
64 Lymph nodes almost entirely replaced with black pigment (melanin)
65 This lymph node has a capsule (1) and some remaining lymphocytes (2) but the remainder of the node is replaced by tumor cells.
66 Remaining portion of lymph node (arrow) The rest of the lymph node is invaded by a neoplasm composed of cells with lighter eosinophilic cytoplasm and pigment
67 Abundant extracellular melanin (arrows) surrounding the tumor cells This section of neoplasm shows the numerous cells with abundant cytoplasm and brown pigment within the cytoplasm of some of these cells.
68 Abundant extracellular melanin (brown pigment) surrounding the tumor cells
69 Main tumor mass with the cells growing as poorly formed nests and sheets of cells There is little if any pigment in this section.
70 Main tumor massThe individual melanoma cells contain large nuclei with irregular contours having chromatin clumped at the periphery of the nuclear membrane and prominent red (eosinophilic) nucleoli.
72 Bronchogenic Carcinoma The large tumor mass can be seen adjacent to the bronchus (1). Note that the epithelium surface of the bronchus is rough and irregular (2). The first branch off of the right main stem bronchus is partially occluded by the thickened mucosa and submucosa (3).
73 Normal mucosa (1) with transition to carcinoma (2) Note the bronchial cartilage (3) and the invasion of tumor through the entire wall of the bronchus with tumor extending to the serosal surface (4).
74 Bronchus1: Ulcerated mucosal surface2: The submucosa is completely filled with tumor down to the cartilage
75 Bronchus with ulcerated mucosal surface on the right and tumor underneath
76 Mucosal surface (right) with an area of hemorrhage (arrow) and underlying tumor (left)
77 Area of invasion with compression of fibrous stroma and focal necrosis
78 Cytologic detail of tumor 1: Area of necrosis2: A more differentiated area with keratin pearl formation
84 Tumor growth pattern: Cells form discrete islands, trabeculae, and glands
85 The tumor cells are monotonously similar with scant, pink, granular cytoplasm and a round-to-oval stippled nucleus. As in most carcinoid tumors, there is minimal variation in cell and nuclear size, and mitoses are infrequent or absent.
86 Subcutaneous masses in cecum Note that the mucosa (1) is mostly normal and the tumor cells are in the submucosa (2).
87 Higher power of previous image Intact mucosa (right) and the submucosal carcinoid tumor
88 Subcutaneous mass in cecum The mucosa is normal and the tumor cells are in the submucosa.
89 1: Intact mucosa2: A gland3: Submucosal carcinoid tumor cells
90 Cecum containing tumor stained to demonstrate the secretory granules in these tumor cells (brown-colored stain)The blue color is the mucin in the glands just under the mucosal surface.
91 Higher power view of previous image Brown: Carcinoid tumor cellsBlue: Glands
92 Section from previous images stained with silver to delineate carcinoid tumor cells