Dr.Nazar Jawhar
Dr.Nazar JawharNeoplasia is new, uncontrolled growth of cells that is not under physiologic control. The term "cancer" implies malignancy. There is no single mechanism by which a neoplasm arises. Many different mechanisms give rise to neoplasms, and that is what makes diagnosis and treatment so challenging
Nomenclature of Neoplasia Based upon origin: Malignant epithelial neoplasms (carcinoma) e.g: Squamous cell carcinoma of cervix Adenocarcinoma of stomach Hepatocellular carcinoma Renal cell carcinoma Basal cell carcinoma Malignancies arising from mesenchymal tissue (sarcomas). Examples include: Leiomyosarcoma Chondrosarcoma Osteosarcoma Liposarcoma
Nomenclature of Neoplasia Neoplasms with more than one cell type are called "mixed tumors". The best example is the benign mixed tumor (also called pleomorphic adenoma) of salivary gland. Neoplasms with more than one cell type and arising from more than one germ layer are called teratomas. Such neoplasms are common in the ovary
The first step toward neoplasia is cellular transformation Here, there is normal cervical squamous epithelium at the left, but dysplastic squamous epithelium at the right. The dysplastic epithelial cells are darker, smaller, and more crowded, without an orderly process of maturation. Dysplasia is a disorderly growth of epithelium, but still confined to the epithelium. Dysplasia is still reversible.
At high magnification, the normal cervical squamous epithelium at the left merges into the dysplastic squamous epithelium at the right in which the cells are more disorderly and have darker nuclei with more irregular outlines
When an entire portion of epithelium is composed of abnormal cells and no normal epithelial cells remain, and the process is not potentially reversible, then the process has gone beyond dysplasia and is now neoplasia, which is loss of control of the cellular proliferative process. If the basement membrane is still intact, as shown here, then the process is called "carcinoma in situ" because the carcinoma is still confined to the epithelium
Dr.Nazar Jawhar
Dr.Nazar JawharDr.Nazar Jawhar
Squamous papillomaA benign epithelial tumor arising from surface epithelium. Present as a projection above the epithelial surface.
Dr.Nazar Jawhar
Squamous papillomaMicroscopically , it present as a branching, finger-like projection having a fibrovascular core covered by a benign-squamous epithelium.
Dr.Nazar Jawhar
Here is a benign epithelial neoplasm (Thyroid adenoma). It is rounded, well circumscribed and surrounded by a thin white capsule.Dr.Nazar Jawhar
The follicular adenoma is at the center to upper left. This adenoma is a well- differentiated neoplasm because it closely resemble normal tissue. The follicles of the adenoma contain colloid, but there is greater variability in size than normal. Normal thyroid follicles appear at the lower right.
Here is a small hepatic adenoma, an uncommon benign neoplasm, but one that shows how well-demarcated a benign neoplasm is. It also illustrates how function of the normal tissue can be maintained, because this adenoma is making bile pigment, giving it a green color with formalin fixation.
Dr.Nazar Jawhar
Multiple adenomatous polyps of the cecum are seen.Dr.Nazar Jawhar
Uterus with leiomyomas of varying size, but all benign and well-circumscribed firm white masses.Dr.Nazar Jawhar
The microscopic appearance of a leiomyoma indicates that the cells do not vary greatly in size and shape and closely resemble normal smooth muscle cells. No atypiaDr.Nazar Jawhar
Lipoma: It is a benign stromal tumor of adipose tissue, seen in a variety of locations (subcutaneous tissue & in many organ). Here is a benign lipoma on the serosal surface of the small intestine. It has the characteristics of a benign neoplasm: it is well circumscribed, slow growing, non-invasive, and closely resembles the tissue of origin (fat)..At low power magnification, a lipoma is seen to be well demarcated. This neoplasm is so well-differentiated that, except for its appearance as a localized mass, it is impossible to tell from normal adipose tissue. Benign neoplasms are always well differentiated.
Dr.Nazar Jawhar
Lipoma: Microscopically is show sheets of mature normal looking adipocystesThis schwannoma was resected from a nerve. This neoplasm arises from the Schwann cells that myelinate peripheral nerve fibers. Note the circumscribed nature of this benign neoplasm.
The schwannoma is seen microscopically to be composed of spindle cells (like most neoplasms of mesenchymal origin), but the cells are fairly uniform and there is plenty of pink cytoplasm. These are characteristics for a benign neoplasm..
Dr.Nazar Jawhar
HEMANGIOMA: The most common vascular neoplasm, mostly localized, the majority are superficial lesions often in the head and neck, but may occur internally (commonly in the liver). Common in infancy and childhood, most are present from birth and expand with the growth of the child, but some may regress spontaneously before puberty.Dr.Nazar Jawhar
Capillary hemangioma: The most common type. Mostly in the skin and mucous membrane of the head and neck.( e.g strawberry type ( 1 in 200 birhts), presents at birth, grow rapidly and then fades when the child is 1-3 years old.)Dr.Nazar Jawhar
Dr.Nazar Jawhar
Capillary hemangioma: M.I: Composed of closely packed thin-walled capillaries filled with blood.
Dr.Nazar Jawhar
Cavernous hemangioma: Less common than capillary type. characterized by the formation of large, dilated and intercommunicating vascular channels filled with blood. Mostly seen in the deep structure & liver.Dr.Nazar Jawhar
LymphangiomaRemember that the most common neoplasm is a benign nevus (pigmented mole) of the skin, and most people have several, as seen here over the skin of the chest. It is a benign tumor of melanocytic cells.
Dr.Nazar Jawhar
Benign Tumor: Fibroadenoma, an example of mixed tumorHere is a small, round fibroadenoma of the breast, a benign neoplasm most commonly diagnosed in younger women of reproductive age.It is a benign mixed tumor
Dr.Nazar Jawhar
Here is the microscopic appearance of a fibroadenoma. To the right is compressed breast connective tissue forming a "capsule" to this mass. The neoplasm itself is composed of a fibroblastic stroma in which are located elongated compressed ducts lined by benign appearing epithelium.Dr.Nazar Jawhar
Dr.Nazar JawharHepatocellular carcinoma is not well circumscribed (note the infiltration of tumor off to the lower right) nor uniform in consistency. It is also arising in a cirrhotic (nodular) liver.
Dr.Nazar Jawhar
This infiltrating ductal carcinoma of the breast is definitely infiltrating the surrounding breast. The central white area is very hard and gritty, because the neoplasm is producing a desmoplastic reaction with lots of collagen. This is often called a "scirrhous" appearance.Dr.Nazar Jawhar
Dr.Nazar JawharThis is a squamous cell carcinoma arising on the dorsum of the hand
Dr.Nazar Jawhar
The normal squamous epithelium at the left merges into the squamous cell carcinoma at the right, which is infiltrating downward. The neoplastic squamous cells are still similar to the normal squamous cells, but are less orderly. This is a well-differentiated squamous cell carcinoma
Dr.Nazar Jawhar
A squamous cell carcinoma is seen at medium power. Note the pleomorphism of the cells. A "squamous eddy" is seen at the upper left, but some of the cells at the right show little keratinization.Dr.Nazar Jawhar
Here is a moderately differentiated squamous cell carcinoma in which some, but not all, of the neoplastic cells in nests have pink keratin. In general, neoplasms with less differentiation are more aggressive.This is a neoplasm arising in the epithelium of the uterine cervix.( squamous cell carcinoma).Ill-defined fungating mass.
This is the microscopic appearance of carcinoma in the uterine cervix. It is arising in the cervical squamous epithelium. Here, the neoplasm is infiltrating into the underlying cervical stroma.
This is a squamous cell carcinoma. Note the disorderly growth of the squamous epithelial cells in these large nests with pink keratin in the centers. Thus, these neoplastic cells retain the ability to make keratin, similar to normal squamous epithelial cells. Neoplasms may retain characteristics of their cell of origin.
Dr.Nazar Jawhar
This is a basal cell carcinoma:Grossly, they are pearly white nodules of varying size, often with a central area of ulceration and telangiectatic blood vessels around themDr.Nazar Jawhar
This is a basal cell carcinoma of the lower lip. It has a pearly pink border and an ulcerated center
Dr.Nazar Jawhar
The cells of a basal cell carcinoma are dark blue and oblong with scant cytoplasm. They resemble the cells along the basal layer of normal epidermis.Dr.Nazar Jawhar
Nests of basaloid cells are dropping off into the upper dermis in this example of a basal cell carcinoma of the skinDr.Nazar Jawhar
This is an adenocarcinoma of the colon. The surface of the neoplasm is polypoid and reddish pink.Dr.Nazar Jawhar
Here is a gastric adenocarcinoma. A fungating mass.Dr.Nazar Jawhar
A moderately differentiated gastric adenocarcinoma is infiltrating up and into the submucosa below the squamous mucosa of the esophagus. The neoplastic glands are variably sized.Dr.Nazar Jawhar
The infiltrating glands of this colonic adenocarcinoma demonstrate less differentiation , although they still resemble glands. In general, less differentiation means a greater likelihood of malignant behavior.Dr.Nazar Jawhar
At higher magnification, the neoplastic glands of adenocarcinoma demonstrate mitoses, increased nuclear/cytoplasmic ratios, and hyperchromatism. There is a desmoplastic stromal reaction to the infiltrating glands.This renal cell carcinoma: demonstrates distortion and displacement of the normal renal parenchyma by the tumor mass in the lower pole of this kidney. This malignant neoplasm has a variegated appearance on its cut surface, with yellow to white to red to brown areas.
This excision of skin demonstrates a malignant melanoma, which is much larger and more irregular than a benign nevus. From the history provided by the patient, we know that it grew quickly in size in 3 months. In contrast, a benign nevus hardly seems to change at all over many years..
Dr.Nazar Jawhar
This large fleshy mass is an example of a sarcoma. Sarcomas arise from mesenchymal tissues. Sarcomas are big and bad.Here is a fleshy mass arising in the soft tissues of the lower leg. The tibia and the fibula are seen in cross section. This neoplasm proved to be a high-grade undifferentiated pleomorphic sarcoma (HGUPS), a designation replacing the prior term malignant fibrous histiocytoma. Sarcomas tend to invade locally, as can be seen here by the ill-defined margins of the mass..
Sarcomas tend to have a spindle cell pattern. Note that some of these neoplastic cells are much larger than others, and thus very pleomorphic..
This sarcoma seen at medium magnification is composed of pleomorphic cells that vary markedly in size and shape. Note the increased amounts of nuclear DNA, making them hyperchromatic.
This sarcoma has many mitoses. A very large abnormal mitotic figure is seen at the right..
Here is an osteosarcoma of bone. The large, bulky mass arises in the cortex of the bone and extends outward..This large mass lesion is a liposarcoma. Common sites are the retroperitoneum and thigh, and they occur in middle aged to older adults. This one is yellowish, like adipose tissue, and is well-differentiated. Though indolent, it continues growing to reach a large size, and following excision, it has a tendency to recur.
This liposarcoma has enough differentiation to determine the cell of origin (adipocyte), but there is still significant pleomorphism of these neoplastic cells (lipoblasts.
At high magnification, large bizarre lipoblasts are seen in this liposarcoma. Sarcomas are best treated surgically. The response of sarcomas to chemotherapy and/or radiation is variable..
Dr.Nazar Jawhar
Dr.Nazar Jawhar
Adenomatous polyp of the colon. Well differentiated tumor.Note the difference in staining quality between the epithelial cells of the adenoma at the top and the normal glandular epithelium of the colonic mucosa below.Dr.Nazar Jawhar
At high magnification, the normal colonic epithelium at the left contrasts with the atypical epithelium of the adenomatous polyp at the right. Nuclei are darker and more irregularly sized and closer together in the adenomatous polyp than in the normal mucosa. However, the overall difference between them is not great, so this benign neoplasm mimics the normal tissue quite well and this, therefore, well-differentiatedDr.Nazar Jawhar
The infiltrating glands of this colonic adenocarcinoma demonstrate less differentiation than the adenomatous polyp, although they still resemble glands. In general, less differentiation means a greater likelihood of malignant behavior.Dr.Nazar Jawhar
The normal squamous epithelium at the left merges into the squamous cell carcinoma at the right, which is infiltrating downward. The neoplastic squamous cells are still similar to the normal squamous cells, but are less orderly. This is a well-differentiated squamous cell carcinomaDr.Nazar Jawhar
Here is a moderately differentiated squamous cell carcinoma in which some, but not all, of the neoplastic cells in nests have pink keratin. In general, neoplasms with less differentiation are more aggressive.Dr.Nazar Jawhar
This neoplasm is so poorly differentiated that it is difficult to tell what the cell of origin is. It is probably a carcinoma because of the polygonal nature of the cells. Note that nucleoli are numerous and large in this neoplasm. Neoplasms with no differentiation are said to be anaplastic.Dr.Nazar Jawhar
This is a poorly differentiated tumor. Note the marked pleomorphism.Dr.Nazar Jawhar
Mitotic figure is seen in the center, surrounded by malignant squamous cell carcinoma with pleomorphism and minimal pink keratinization. In general, mitoses are more likely to be seen in malignant neoplasms. Remember, though, that normally cells are actively dividing in bone marrow, gonads, and gastrointestinal tract.Dr.Nazar Jawhar
Here are three abnormal mitoses. Mitoses by themselves are not indicators of malignancy. However, abnormal mitoses are highly indicative of malignancy. The marked pleomorphism and hyperchromatism of surrounding cells also favors malignancy.Dr.Nazar Jawhar
This sarcoma has many mitoses. A very large abnormal mitotic figure is seen at the right.Dr.Nazar Jawhar
Dr.Nazar JawharHere is the normal appearance of a benign reactive lymph node. At the top is the capsule and just under that a subcapsular sinus where lymphatics enter that drain tissues peripheral to the node. Beneath the capsule is the paracortical zone with lymphoid follicles having a pale germinal center in which the immune responses are often generated. Beneath this are sinusoids extending to the center of the node.
Dr.Nazar Jawhar
Tumors invade lymphatics and spread to the local draining lymph node. •Here, colonization occurs first underneath the capsule in the marginal sinus. •Subsequently, the entire lymph node may be involvedDr.Nazar Jawhar
Microscopically, metastatic adenocarcinoma is seen in a lymph node here. It is common for carcinomas to metastasize to lymph nodes. The first nodes involved are those draining the site of the primary.Dr.Nazar Jawhar
This is an example of metastases to the liver. Note that the tan-white masses are multiple and irregularly sized. A primary neoplasm is more likely to be a solitary mass. Metastasis is the best indication that a neoplasm is malignant
Malignant neoplasms are capable of metastasizing. A metastasis represents a malignant neoplasm that has traveled from its primary site of origin to a distant site. This is an example of metastases to the liver. Note that the tan-white masses are multiple and irregularly sized. Like many large metastatic lesions, there is central necrosis.
Dr.Nazar Jawhar
Microscopically, metastatic infiltrating ductal carcinoma from breast is seen on the right, with normal liver parenchyma on the leftDr.Nazar Jawhar
Malignant neoplasms characterized by the tendency to invade surrounding tissues. Here, a lung cancer is seen to extend to surrounding lung parenchyma.Dr.Nazar Jawhar
Both lymphatic and hematogenous spread of malignant neoplasms is possible to distant sites. Here, a breast carcinoma has spread to the lung.Dr.Nazar Jawhar
Neoplasms can spread by seeding along body cavities, and this pattern is more typical for carcinomas than other neoplasms. Note the multitude of small tan tumor nodules seen over the peritoneal surface of the mesentery shown here.Branches of peripheral nerve are invaded by nests of malignant cells. This is termed perineural invasion. This is often the reason why there is pain associated with cancers and why that pain is unrelenting..
Neoplasia in the pediatric age range is not common. Childhood malignancies are rare, but those that occur often have the appearance of primitive "small round blue cell tumors" such as the neuroblastoma seen here.