Tumor tissue structure and cell morphology are different from corresponding normal tissues to varying degrees.

structural heterogeneity

cellular atypia

Tumors with obvious atypia

benign tumors of solid organs

The growth rate is slow. As the size increases, the tumor pushes but does not invade surrounding tissues. It is clearly segmented and can form a complete fibrous capsule around the tumor.

extrusion

Lipoma

Body surface, inner surface of body cavity, ductal and organ cavity surface

growth convex surface

Invasive growth can occur at the base of malignant tumors

Ulcers form after shedding

malignant tumor

The phenomenon of tumor cells growing into and destroying surrounding tissue is called invasion

Based on violation of base membrane

No membrane exists

No clear boundaries with surrounding tissue

The most common metastasis pattern of epithelial malignant tumors

Marginal sinuses that reach regional lymph nodes first

Metastases from veins to the lungs, such as osteosarcoma

Metastases from the portal vein to the liver, such as gastrointestinal cancer

The lungs and liver are most commonly affected

Choriocarcinoma occurs early in blood vessel metastasis

The morphological characteristics are clear boundaries, scattered distribution, and mostly close to the surface of the organ.

primary site

transfer method

Example

Covering epithelium such as squamous epithelium, urothelium

in general

under the mirror

Glandular epithelium, such as intestinal mammary gland thyroid gland

Tubular adenoma (villous adenoma)

cystadenoma

fibroadenoma

papillary adenocarcinoma

cystadenocarcinoma

papillary cystadenocarcinoma

Mucinous carcinoma (colloid carcinoma)

The higher the grade, the more likely it is to relapse and infiltrate deeply.

fibrous tissue hyperplasia

Subcutaneously on limbs and trunk

Nodular shape, clear boundary with surrounding tissue, grayish-white cut surface, visible braided stripes, hard texture

The collagen fibers in the tumor tissue are in the form of bundles and are woven with each other. There are slender fiber cells between the fibers. Generally, there are no mitotic figures.

Slow growth and less likely to relapse after removal

Subcutaneous tissue of back, shoulders and proximal extremities

Most common benign soft tissue tumors

There is a film, the cut surface is yellow, like adipose tissue

Similar to normal adipose tissue, with fibrous membrane

Mostly occur congenitally, often in children, and may resolve spontaneously in adulthood.

capillary hemangioma

cavernous hemangioma

venous hemangioma

Deep, opposite to lipoma distribution

Characterized by the appearance of lipoblasts

Papules or nodules, dark red and gray-white, prone to necrosis and bleeding

Subcutaneous tissue of limbs

infiltrative growth

Grayish white, fish-like, often accompanied by hemorrhage and necrosis

Atypical spindle cell herring bone arrangement

Most common bone malignant tumors

More common in teenagers

The triangular bulge formed between the cortical bone at the upper and lower ends of the tumor and the lifted episteum is the new bone produced by the episteum. Codman's triangle is seen on X-ray.

The periosteum is turned up, and vertical radial reactive new bone trabeculae are formed between the episteum and bone cortex, which appear as sun-ray shadows on X-ray.

Tumor cells have obvious atypia and form tumorous osteoid tissue or bone tissue, which is the most important basis for diagnosis.