CHOP is the acronym for a

chemotherapy regimen A chemotherapy regimen is a regimen for chemotherapy, defining the drugs to be used, their dosage, the frequency and duration of treatments, and other considerations. In modern oncology, many regimens combine several chemotherapy drugs in combinat ...

used in the treatment of

non-Hodgkin lymphoma Non-Hodgkin lymphoma (NHL), also known as non-Hodgkin's lymphoma, is a group of blood cancers that includes all types of lymphomas except Hodgkin lymphomas. Symptoms include enlarged lymph nodes, fever, night sweats, weight loss, and tiredness. ...

. CHOP consists of: * Cyclophosphamide, an

alkylating agent Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting al ...

which damages DNA by binding to it and causing the formation of cross-links * (also called doxorubicin or adriamycin), an intercalating agent which damages DNA by inserting itself between DNA bases * (

vincristine Vincristine, also known as leurocristine and marketed under the brand name Oncovin among others, is a chemotherapy medication used to treat a number of types of cancer. This includes acute lymphocytic leukemia, acute myeloid leukemia, Hodgkin's ...

), which prevents cells from duplicating by binding to the protein tubulin * or , which are

corticosteroid Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involv ...

s. Sometimes the chimeric anti- CD20 monoclonal antibody,

rituximab Rituximab, sold under the brand name Rituxan among others, is a monoclonal antibody medication used to treat certain autoimmune diseases and types of cancer. It is used for non-Hodgkin lymphoma, chronic lymphocytic leukemia (in non-geriatric p ...

, is added to this treatment regimen to form the R-CHOP regimen.

Dosing regimen

R-Maxi-CHOP is used in mantle cell lymphoma and is given in 21-day intervals, alternating with

R-HDAC R-HDAC, or R-HD-AraC ( (R)ituximab plus (H)igh (D)ose (A)ra-(C)) is a chemotherapy regimen that is used, alternating with R-Maxi-CHOP, as part of so-called "Nordic protocol" of treating mantle cell lymphoma. It consists of monoclonal antibody rit ...

(rituximab + high-dose cytarabine). In most other non-Hodgkin lymphomas (excluding some aggressive forms), standard-dose CHOP is generally used as first-line therapy.

Uses and indications

Normal cells are more able than cancer cells to repair damage from chemotherapy drugs. This regimen can also be combined with the monoclonal antibody

if the lymphoma is of

B cell B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or ...

origin; this combination is called R-CHOP. Typically, courses are administered at an interval of two or three weeks (CHOP-14 and CHOP-21 respectively). A staging

CT scan A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

is generally performed after three cycles to assess whether the disease is responding to treatment. In patients with a history of

cardiovascular disease Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, h ...

, doxorubicin (which is cardiotoxic) is often deemed to be too great a risk and is omitted from the regimen. The combination is then referred to as COP (cyclophosphamide, Oncovin, and prednisone or prednisolone) or CVP (cyclophosphamide, vincristine, and prednisone or prednisolone).

Side-effects and complications

The combination is generally well tolerated.

Chemotherapy-induced nausea and vomiting Chemotherapy-induced nausea and vomiting (CINV) is a common side-effect of many cancer treatments. Nausea and vomiting are two of the most feared cancer treatment-related side effects for cancer patients and their families. In 1983, Coates et al. f ...

may require antiemetics (such as ondansetron), and

hemorrhagic cystitis Hemorrhagic cystitis or haemorrhagic cystitis is an inflammation of the bladder defined by lower urinary tract symptoms that include dysuria, hematuria, and hemorrhage. The disease can occur as a complication of cyclophosphamide, ifosfamide and rad ...

is prevented with administration of mesna. Alopecia (hair loss) is common.

Neutropenia Neutropenia is an abnormally low concentration of neutrophils (a type of white blood cell) in the blood. Neutrophils make up the majority of circulating white blood cells and serve as the primary defense against infections by destroying bacteria ...

generally develops in the second week. During this period, many clinicians recommend

pegfilgrastim Pegfilgrastim, sold under the brand name Neulasta among others, is a PEGylated form of the recombinant human granulocyte colony-stimulating factor (GCSF) analog filgrastim. It serves to stimulate the production of white blood cells (neutrophils) ...

or prophylactic use of

ciprofloxacin Ciprofloxacin is a fluoroquinolone antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra abdominal infections, certain types of infectious diarrhea, respiratory tract infections, skin infec ...

. If a

fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...

develops in the

neutropenic Neutropenia is an abnormally low concentration of neutrophils (a type of white blood cell) in the blood. Neutrophils make up the majority of circulating white blood cells and serve as the primary defense against infections by destroying bacteria ...

period, urgent medical assessment is required for neutropenic sepsis, as infections in patients with low

neutrophil Neutrophils (also known as neutrocytes or heterophils) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. They form an essential part of the innate immune system, with their functions varying in ...

counts may progress rapidly. Allopurinol is typically co-administered prophylactically to prevent hyperuricemia that results from

tumor lysis syndrome Tumor lysis syndrome (TLS) is a group of metabolic abnormalities that can occur as a complication from the treatment of cancer, where large amounts of tumor cells are killed off ( lysed) from the treatment, releasing their contents into the blood ...

, the result of rapid death of tumor cells.

History

A pivotal study published in 1993 compared CHOP to several other chemotherapy regimens (e.g. m-BACOD,

ProMACE-CytaBOM A chemotherapy regimen is a regimen for chemotherapy, defining the drugs to be used, their dosage, the frequency and duration of treatments, and other considerations. In modern oncology, many regimens combine several list of chemotherapeutic agents ...

, MACOP-B) for advanced non-Hodgkin's lymphoma. CHOP emerged as the regimen with the least toxicity but similar efficacy. However, in Germany in 2012,

bendamustine Bendamustine, sold under the brand name Treanda among others, is a chemotherapy medication used in the treatment of chronic lymphocytic leukemia (CLL), multiple myeloma, and non-Hodgkin's lymphoma. It is given by injection into a vein. Common s ...

has displaced -HOP to become the first line treatment of choice for

indolent lymphoma 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. Symp ...

(a less aggressive subset of non-Hodgkin lymphoma).

CHOEP modification

In order to develop more effective first-line chemotherapy regimen for aggressive lymphomas, some researchers tried to add to the standard CHOP regimen. There were also attempts to further improve the efficacy of the CHOEP regimen with escalating the chemotherapy doses. This mode was called High-CHOEP. However, it did not show more effectiveness than standard-dose CHOEP while adding more toxicity and cost. In order to try improving efficacy of the CHOEP, some researchers tried to escalate chemotherapy to very high doses, requiring autologous stem cell support in each cycle. Doses in that regimen were increased from cycle to cycle. This regimen was called MegaCHOEP. But again, such escalation seemed to not improve effectiveness while adding toxicity.

References