Lymphoma is a group of blood and lymph tumors that develop from lymphocytes. The name typically refers to just the cancerous versions rather than all such tumours. Signs and symptoms may include enlarged lymph nodes, fever, drenching sweats, unintended weight loss, itching, and constantly feeling tired. The enlarged lymph nodes are usually painless. The sweats are most common at night.
Tumors of the hematopoietic and lymphoid tissues or tumours of the haematopoietic and lymphoid tissues are tumors that affect the blood, bone marrow, lymph, and lymphatic system. Because these tissues are all intimately connected through both the circulatory system and the immune system, a disease affecting one will often affect the others as well, making aplasia, myeloproliferation and lymphoproliferation closely related and often overlapping problems. While uncommon in solid tumors, chromosomal translocations are a common cause of these diseases. This commonly leads to a different approach in diagnosis and treatment of hematological malignancies. Hematological malignancies are malignant neoplasms ("cancer"), and they are generally treated by specialists in hematology and/or oncology. In some centers "hematology/oncology" is a single subspecialty of internal medicine while in others they are considered separate divisions. Not all hematological disorders are malignant ("cancerous"); these other blood conditions may also be managed by a hematologist.
Cutaneous T-cell lymphoma (CTCL) is a class of non-Hodgkin lymphoma, which is a type of cancer of the immune system. Unlike most non-Hodgkin lymphomas, CTCL is caused by a mutation of T cells. The cancerous T cells in the body initially migrate to the skin, causing various lesions to appear. These lesions change shape as the disease progresses, typically beginning as what appears to be a rash which can be very itchy and eventually forming plaques and tumors before spreading to other parts of the body.
Follicular lymphoma (FL) is a cancer that involves certain types of white blood cells known as lymphocytes. The cancer originates from the uncontrolled division of specific types of B-cells known as centrocytes and centroblasts. These cells normally occupy the follicles in the germinal centers of lymphoid tissues such as lymph nodes. The cancerous cells in FL typically form follicular or follicle-like structures in the tissues they invade. These structures are usually the dominant histological feature of this cancer.
The B-cell lymphomas are types of lymphoma affecting B cells. Lymphomas are "blood cancers" in the lymph nodes. They develop more frequently in older adults and in immunocompromised individuals.
Intravascular lymphomas (IVL) are rare cancers in which malignant lymphocytes proliferate and accumulate within blood vessels. Almost all other types of lymphoma involve the proliferation and accumulation of malignant lymphocytes in lymph nodes, other parts of the lymphatic system, and various non-lymphatic organs but not in blood vessels.
Diffuse large B-cell lymphoma (DLBCL) is a cancer of B cells, a type of lymphocyte that is responsible for producing antibodies. It is the most common form of non-Hodgkin lymphoma among adults, with an annual incidence of 7–8 cases per 100,000 people per year in the US and UK. This cancer occurs primarily in older individuals, with a median age of diagnosis at ~70 years, although it can occur in young adults and, in rare cases, children. DLBCL can arise in virtually any part of the body and, depending on various factors, is often a very aggressive malignancy. The first sign of this illness is typically the observation of a rapidly growing mass or tissue infiltration that is sometimes associated with systemic B symptoms, e.g. fever, weight loss, and night sweats.
Lymphoid hyperplasia is the rapid proliferation of normal lymphocytic cells that resemble lymph tissue which may occur with bacterial or viral infections. The growth is termed hyperplasia which may result in enlargement of various tissue including an organ, or cause a cutaneous lesion.
Marginal zone lymphomas, also known as marginal zone B-cell lymphomas (MZLs), are a heterogeneous group of lymphomas that derive from the malignant transformation of marginal zone B-cells. Marginal zone B cells are innate lymphoid cells that normally function by rapidly mounting IgM antibody immune responses to antigens such as those presented by infectious agents and damaged tissues. They are lymphocytes of the B-cell line that originate and mature in secondary lymphoid follicles and then move to the marginal zones of mucosa-associated lymphoid tissue (MALT), the spleen, or lymph nodes. Mucosa-associated lymphoid tissue is a diffuse system of small concentrations of lymphoid tissue found in various submucosal membrane sites of the body such as the gastrointestinal tract, mouth, nasal cavity, pharynx, thyroid gland, breast, lung, salivary glands, eye, skin and the human spleen.
Pagetoid reticulosis is a cutaneous condition, an uncommon lymphoproliferative disorder, sometimes considered a form of mycosis fungoides.
Primary cutaneous immunocytoma was initially regarded as a distinct type of the cutaneous lymphomas of the skin. A 1997 review characterized 16 cases of primary cutaneious immunocytomo as skin lesions located on the arms and legs that in 15 of 16 cases had an excellent responses to, and prognoses after, purely local treatments. On microscopic histological examination, these lesions consisted of B cells and nodular or diffuse infiltrates of lymphoplasmacytoid-like plasma cells located at the periphery of these infiltrates. In 2004, however, the World Health Organization and European Organisation for Research and Treatment of Cancer classified primary cutaneous immunocytoma as one form of the primary cutaneous marginal zone lymphomas or, as they are now termed, primary cutaneous marginal zone lymphoproliferative disorders.
Primary cutaneous marginal zone lymphomas represent a heterogeneous group of diseases characterized by solitary or multiple dermal or subcutaneous nodules. Lymphomas included in this group are:
Plasmablastic lymphoma (PBL) is a type of large B-cell lymphoma recognized by the World Health Organization (WHO) in 2017 as belonging to a subgroup of lymphomas termed lymphoid neoplasms with plasmablastic differentiation. The other lymphoid neoplasms within this subgroup are: plasmablastic plasma cell lymphoma ; primary effusion lymphoma that is Kaposi's sarcoma-associated herpesvirus positive or Kaposi's sarcoma-associated Herpesvirus negative; anaplastic lymphoma kinase-positive large B-cell lymphoma; and human herpesvirus 8-positive diffuse large B-cell lymphoma, not otherwise specified. All of these lymphomas are malignancies of plasmablasts, i.e. B-cells that have differentiated into plasmablasts but because of their malignant nature: fail to differentiate further into mature plasma cells; proliferate excessively; and accumulate in and injure various tissues and organs.
Primary cutaneous follicle center lymphoma is a type of lymphoma. It was recognized as a distinct disease entity in the 2008 WHO classification. PCFCL had been previously conceived as a variant of follicular lymphoma (FL).
Epstein–Barr virus positive diffuse large B-cell lymphoma, not otherwise specified is a form of diffuse large B-cell lymphomas (DLBCL) accounting for around 10-15% of DLBCL cases. DLBCL are lymphomas in which B-cell lymphocytes proliferate excessively, invade multiple tissues, and often causes life-threatening tissue damage. EBV+ DLBCL is distinguished from DLBCL in that virtually all the large B cells in the tissue, infiltrates of the Epstien-Barr virus (EBV) express EBV genes characteristic of the virus's latency III or II phase. EBV is a ubiquitous virus, infecting around 95% of the world population.
Epstein–Barr virus–associated lymphoproliferative diseases are a group of disorders in which one or more types of lymphoid cells, i.e. B cells, T cells, NK cells, and histiocytic-dendritic cells, are infected with the Epstein–Barr virus (EBV). This causes the infected cells to divide excessively, and is associated with the development of various non-cancerous, pre-cancerous, and cancerous lymphoproliferative disorders (LPDs). These LPDs include the well-known disorder occurring during the initial infection with the EBV, infectious mononucleosis, and the large number of subsequent disorders that may occur thereafter. The virus is usually involved in the development and/or progression of these LPDs although in some cases it may be an "innocent" bystander, i.e. present in, but not contributing to, the disease.
In situ lymphoid neoplasia is a precancerous condition newly classified by the World Health Organization in 2016. The Organization recognized two subtypes of ISLN: in situ follicular neoplasia (ISFN) and in situ mantle cell neoplasia (ISMCL). ISFN and ISMCL are pathological accumulations of lymphocytes in the germinal centers and mantle zones, respectively, of the follicles that populate lymphoid organs such as lymph nodes. These lymphocytes are monoclonal B-cells that may develop into follicular (FL) and mantle cell (MCL) lymphomas, respectively.
Duodenal-type follicular lymphoma (DFL) is a form of lymphoma in which certain lymphocyte types, the B-cell-derived centrocytes and centroblasts, form lymph node follicle-like structures principally in the duodenum and other parts of the small intestine. It is an indolent disease which on rare occasions progresses to a more aggressive lymphoma that spreads beyond these originally involved sites.
Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) is a cutaneous lymphoma skin disease that occurs mostly in elderly females. In this disease, B cells become malignant, accumulate in the dermis and subcutaneous tissue below the dermis to form red and violaceous skin nodules and tumors. These lesions typically occur on the lower extremities but in uncommon cases may develop on the skin at virtually any other site. In ~10% of cases, the disease presents with one or more skin lesions none of which are on the lower extremities; the disease in these cases is sometimes regarded as a variant of PCDLBL, LT termed primary cutaneous diffuse large B-cell lymphoma, other (PCDLBC-O). PCDLBCL, LT is a subtype of the diffuse large B-cell lymphomas (DLBCL) and has been thought of as a cutaneous counterpart to them. Like most variants and subtypes of the DLBCL, PCDLBCL, LT is an aggressive malignancy. It has a 5-year overall survival rate of 40–55%, although the PCDLBCL-O variant has a better prognosis than cases in which the legs are involved.
Indolent lymphoma, also known as low-grade lymphoma, is a group of slow-growing non-Hodgkin lymphomas (NHLs). Because they spread slowly, they tend to have fewer signs and symptoms when first diagnosed and may not require immediate treatment. Symptoms can include swollen but painless lymph nodes, unexplained fever, and unintended weight loss.
