Histologic geographic variability of diffuse intrinsic pontine glioma (DIPG) - Fonc-02-00205-g003 (cropped)

pathology Pathology is the study of the causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in ...

, grading is a measure of the cell appearance in

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s and other

neoplasm A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s. Some pathology grading systems apply only to

malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

neoplasms (

cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...

); others apply also to

benign Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

neoplasms. The neoplastic grading is a measure of cell

anaplasia Anaplasia (from grc, ἀνά ''ana'', "backward" + πλάσις ''plasis'', "formation") is a condition of cells with poor cellular differentiation, losing the morphological characteristics of mature cells and their orientation with respect to e ...

(reversion of differentiation) in the sampled tumor and is based on the resemblance of the tumor to the tissue of origin. Grading in cancer is distinguished from

staging Staging may refer to: Computing * Staging (cloud computing), a process used to assemble, test, and review a new solution before it is moved into production and the existing solution is decommissioned * Staging (data), intermediately storing data b ...

, which is a measure of the extent to which the cancer has

spread Spread may refer to: Places * Spread, West Virginia Arts, entertainment, and media * ''Spread'' (film), a 2009 film. * ''$pread'', a quarterly magazine by and for sex workers * "Spread", a song by OutKast from their 2003 album ''Speakerboxxx/T ...

. Pathology grading systems classify the microscopic cell appearance abnormality and deviations in their rate of growth with the goal of predicting developments at tissue level (see also the 4 major histological changes in

dysplasia Dysplasia is any of various types of abnormal growth or development of cells (microscopic scale) or organs ( macroscopic scale), and the abnormal histology or anatomical structure(s) resulting from such growth. Dysplasias on a mainly microscopi ...

). Cancer is a disorder of cell life cycle alteration that leads (non-trivially) to excessive

cell proliferation Cell proliferation is the process by which ''a cell grows and divides to produce two daughter cells''. Cell proliferation leads to an exponential increase in cell number and is therefore a rapid mechanism of tissue growth. Cell proliferation r ...

rates, typically longer cell lifespans and poor differentiation. The grade score (numerical: G1 up to G4) increases with the lack of cellular differentiation - it reflects how much the tumor cells differ from the cells of the normal tissue they have originated from (see 'Categories' below). Tumors may be graded on four-tier, three-tier, or two-tier scales, depending on the institution and the tumor type. The histologic tumor grade score along with the

metastatic Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, ...

(whole-body-level cancer-spread) staging are used to evaluate each specific cancer patient, develop their individual treatment strategy and to predict their prognosis. A cancer that is very poorly differentiated is called ''

anaplastic Anaplasia (from grc, ἀνά ''ana'', "backward" + πλάσις ''plasis'', "formation") is a condition of cells with poor cellular differentiation, losing the morphological characteristics of mature cells and their orientation with respect to e ...

''.

Categories

Grading systems are also different for many common types of cancer, though following a similar pattern with grades being increasingly malignant over a range of 1 to 4. If no specific system is used, the following general grades are most commonly used, and recommended by the American Joint Commission on Cancer and other bodies: *GX Grade cannot be assessed *G1 Well differentiated (Low grade) *G2 Moderately differentiated (Intermediate grade) *G3 Poorly differentiated (High grade) *G4 Undifferentiated (High grade)

Specific systems

Of the many cancer-specific schemes, the Gleason system, named after Donald Floyd Gleason, used to grade the adenocarcinoma cells in

prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that su ...

is the most famous. This system uses a grading score ranging from 2 to 10. Lower Gleason scores describe well-differentiated less aggressive tumors. Other systems include the Bloom-Richardson grading system for

breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or ...

and the Fuhrman system for

kidney cancer Kidney cancer, also known as renal cancer, is a group of cancers that starts in the kidney. Symptoms may include blood in the urine, lump in the abdomen, or back pain. Fever, weight loss, and tiredness may also occur. Complications can include sp ...

. Invasive-front grading is useful as well in oral squamous cell carcinoma. For

soft-tissue sarcoma A soft-tissue sarcoma (STS) is a malignant tumour, a type of cancer, that develops in soft tissue. A soft tissue sarcoma is often a painless mass that grows slowly over months or years. They may be superficial or deep-seated. Any such unexplaine ...

two histological grading systems are used : the National Cancer Institute (NCI) system and the French Federation of Cancer Centers Sarcoma Group (FNCLCC) system.Free full text

Examples of grading schemes

References

External links

CancerWeb

{{Tumors Oncology Pathology

Categories

Specific systems

Examples of grading schemes

See also

References

External links