Health

What are the different types of cancer, and how can they be classified?

Cancer is not considered a single disease but several. The classification and types of cancer are based on the site of origin of the illness and its histological characteristics (composition, structure and characteristics) or tissue.

Depending on the site of origin

The primary site of origin gives the classification and types of cancer. They are of a specific kind, such as lung, brain, oral, liver, and kidney cancer.

Depending on the type of fabric

Based on the type of tissue, six main categories of cancer types are classified and identified:

Carcinoma

It is the most common type of cancer and originates in epithelial cells that cover the outside of the body (skin) and internal surfaces (mucosa).

When the carcinoma affects the surface of the organs that have a secretory function in the body, it is called adenocarcinoma (cancer of the breast, lung, colon, pancreas, prostate, etc.)

When the tumour affects the rest of the tissues that line hollow organs and the skin, it is called squamous cell carcinoma or squamous cell carcinoma (cancer of the skin, cervix, bladder, head, neck, vagina, etc.) 

Sarcoma

This type of cancer is widespread in the young population. They are formed in bones (osteosarcoma) and soft tissues (such as muscle, cartilage, adipose or fatty tissue, blood vessels, lymphatic vessels) and fibrous tissues (tendons and ligaments).

Multiple myeloma

This type of cancer starts in the marrow’s plasma cells (a type of white blood cell) in the marrow.

Plasma cells produce antibodies to respond to infections and diseases, so when the DNA of the cells is altered, they accumulate in the bone marrow, forming tumours in many bones.

It is considered a type of blood cancer because the abnormal plasma cells cause the blood to thicken and prevent the bone marrow from generating more healthy blood cells. Leukaemia

This type of cancer I,t does not form solid tumours; they all start in the tissues that form blood in the bone marrow. They are also known as “liquid cancer”.

At present, the marrow produces excess immature white blood cells, which cannot fulfil their function of protection against infections and diseases, making the person more likely to get sick, and the DNA of their healthy cells is altered.

There are several types of leukaemia:

Acute myelocytic leukaemia (AML): It is common in childhood and is a cancer of the myeloid and granulocytic white blood cells.

  • Chronic myelocytic leukaemia (CML): occurs in adulthood and is a cancer of the myeloid and granulocytic white blood cells.
  • Acute lymphocytic, lymphocytic or lymphoblastic leukaemia (ALL): is a malignant neoplasm of lymphoid and lymphocytic white blood cells. It is common during childhood and in young adults.
  • Chronic lymphocytic, lymphocytic, or lymphoblastic leukaemia (CLL): is common in adulthood and is a malignant neoplasm of lymphoid and lymphocytic white blood cells.
  • Polycythemia Vera or erythema is cancer that occurs in the different components of the blood, mainly in the red blood cells.

lymphoma

Cancer originates in the immune system’s cells, specifically in the lymphocytes: T cells or B cells. It belongs to the lymphatic system. Unlike leukaemias, these cancers are “solid” or extranodal lymphomas that affect the lymph nodes in specific organs and places in the body, such as the stomach, brain, intestines, etc.

There are two types of lymphomas: Non-Hodgkin’s lymphoma and Hodgkin’s lymphoma; in the latter, there is the presence of cells called Reed-Sternberg in the tissue, which differentiates it from Non-Hodgkin.

Regarding the recovery prognosis, Hodgkin’s lymphoma has a greater chance of cu. In Non-Hodgkin’s lymphoma it will depend on the specificity of the disease.

Of mixed or rare type

It is when two or more components of cancer, such as a mixed mesodermatumouror, carcinosarcoma, adenosquamous carcinoma, teratocarcinoma, and blastomas, affect effect tissue).

according to grade

The grade of a cancer or tumour is determined from 1 to 4 according to the increase in abnormal cells compared to normal cells. For this, the existence of differentiated or undifferentiated cells in the tissues of and around the tumour is considered:

  • Grade 1 (G1): well-differentiated cells with slight abnormality.
  • Grade 2 (G2): moderately differentiated cells with a slight exception.
  • Grade 3 (G3): poorly differentiated cells with many exceptions.
  • Grade 4 (G4): Cells are immature and primitive, and undifferentiated.

According to the stage or stage

Staging is how cancers are classified individually and the cess of finding out how much cancer is in the body and how much it has spread. Its definition provides essential information for the doctor to plan treatment and determine the prognosis of recovery of the person and the extent of the disease.

There are several methods to perform a staging (TNM) or classification of the state of cancer:

  • Depending on the tumour size (T), which is the most used method, depending on the regional spread or lymph node involvement (N), Distant metastasis (M).

Cancer’s stage is determined by the identified degree (1 to 4) and the location (TNM) in which the disease is found. It is so:

  • T0 means there is no evidence of a tumour.
  • T, from 1 to4, means that the size and involvement of the tumour are increasing.
  • This was hen there is carcinoma in situ or limited to superficial cells.
  • N0 means that there is no lymph node involvement.
  • N, from 1 to 4 are the increasing degrees of involvement in the lymph nodes.
  • This implies that it is impossible to evaluate the lymph nodes’ participation.
  • M0, when there is no evidence of distant spread (metastasis).
  • M1, when there is evidence of distant spread (metastasis).

TNM staging of cancer indicates the following:

  • Stage 0: The tumour is in situ or limited to superficial cells.
  • Phase I: The cancer is limited to the tissue of origin.
  • Stage II: The cancer is limited locally spread.
  • Stage III: The cancer is locally and extensively regionally disseminated.
  • Stage IV: Advanced cancer that is distantly spread and metastasised.

Depending on location in the body

Cancers can be classified according to where they are in the body, which, in general, are:

  • musculoskeletal system
  • bone cancer
  • Osteosarcoma and bone malignant fibrous histiocytoma
  • Sarcoma de Ewing
  • infantile rhabdomyosarcoma
  • soft tissue sarcoma
  • respiratory system and thorax
  • Blastoma pleuropulmonar infantil
  • Non-small cell lung cancer
  • small cell lung cancer
  • Malignant mesothelioma
  • Thymoma and thymic carcinoma
  • Childhood tracheobronchial tumours
  • Head and neck
  • Mouth cancer
  • Throat cancer
  • salivary gland cancer
  • hypopharyngeal cancer
  • Extracranial germ cell tumour in children
  • Cancer of the lip and oral cavity
  • laryngeal cancer
  • nasopharyngeal cancer
  • oropharyngeal cancer
  • parathyroid cancer
  • Paranasal sinus and nasal cavity cancer
  • Thyroid cancer
  • Metastatic squamous cell carcinoma of the neck with primary tumour
  • germ cell
  • The infantile central nervous system, germ cell tumour
  • Extracranial germ cell tumour in children
  • Extragonadal germ cell tumour
  • Ovarian germ cell tumour
  • Testicular cancer
  • brain and nervous system
  • Primary lymphoma of the central nervous system
  • Neuroblastoma
  • brain tumours in adults
  • Tumor cerebral infantil
  • Childhood astrocytomas
  • Brain and spinal cord, description of the treatment of tumours in children
  • Childhood craniopharyngioma
  • Ependymoma infantile
  • Children’s brainstem glioma
  • Medulloblastoma and other embryonal tumours of the childhood central nervous system
  • Childhood central nervous system atypical teratoid rhabdoid tumour
  • Germ cell tumours of the infantile central nervous system
  • Childhood central nervous system embryonal tumours
  • Primitive supratentorial neuroectodermal tumours
  • Digestive and gastrointestinal anal cancer
  • Colon cancer
  • Oesophagus cancer
  • Stomach (gastric) cancer
  • Liver cancer in adults (primary)
  • childhood liver cancer
  • small intestine cancer
  • Extrahepatic bile duct cancer
  • Pancreatic cancer
  • rectal cancer
  • gallbladder cancer
  • Tumor carcinoide gastrointestinal
  • Childhood gastrointestinal stromal tumours
  • Neuroendocrine tumours of the pancreas (islet cell tumours)
  • endocrine and neuroendocrine
  • Thyroid cancer
  • parathyroid cancer
  • Adrenal cortex carcinoma
  • Merkel cell carcinoma
  • Pheochromocytoma
  • Paraganglioma
  • Tumor carcinoide gastrointestinal
  • pituitary tumour
  • Neuroendocrinetumourr, non-small cell lung
  • Neuroendocrine tumour, small cell lung
  • Pancreatic neuroendocrine tumours (islet cell tumours)
  • Melanoma ocular uveal
  • Retinoblastoma
  • Skin
  • Skin cancer
  • Merkel cell carcinoma

Carcinoma of the unknown primary site

  • AIDS-related cancers
  • AIDS-related lymphoma
  • Primary lymphoma of the central nervous system
  • Kaposi’s sarcoma
  • Kidneys and genitourinary system
  • Renal cell (kidney) cancer
  • Transitional cell cancer of the renal pelvis and ureter
  • penile cancer
  • Prostate cancer
  • Testicular cancer
  • urethral cancer
  • Bladder cancer
  • Wilms tumour and other childhood kidney tumours
  • Blood and haematological system
  • Leukaemia
  • hairy cell leukaemia
  • Acute lymphoblastic leukaemia in adults
  • Childhood acute lymphoblastic leukaemia
  • Chronic lymphocytic leukaemia
  • Chronic myelogenous leukaemia
  • Acute myeloid leukaemia in adults
  • Childhood acute myeloid leukaemia and other myeloid malignancies
  • lymphoma
  • Cutaneous T-cell lymphoma, see Mycosis fungoides and Sézary syndrome
  • Hodgkin lymphoma in adults
  • Childhood Hodgkin lymphoma
  • Non-Hodgkin lymphoma in adults
  • Childhood non-Hodgkin lymphoma
  • Primary lymphoma of the central nervous system
  • AIDS-related lymphoma
  • Mycosis fungoides and Sézary syndrome
  • Waldenström, macroglobulinemia

Others

  • Histiocytosis of Langerhans cells
  • Multiple myeloma and other plasma cell neoplasms
  • Myelodysplastic or myeloproliferative neoplasms
  • Chronic myeloproliferative neoplasms

breast cancer

  • Childhood breast cancer
  • Male breast cancer
  • Pregnancy and breast cancer

Female reproductive system

  • Cervical cancer
  • Endometrial cancer
  • ovarian epithelial cancer
  • fallopian tube cancer
  • vaginal cancer
  • vulvar cancer
  • Primary cancer of the peritoneum
  • Gestational trophoblastic disease
  • Uterine or uterine sarcoma
  • Ovarian germ cell tumour
  • Ovarian low malignant potential tumour