Merck Manual

Please confirm that you are a health care professional

Loading

Overview of Cancer Therapy

By

Robert Peter Gale

, MD, PhD, Imperial College London

Last full review/revision Jul 2018| Content last modified Jul 2018
Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Topic Resources

Curing cancer requires eliminating all cells capable of causing cancer recurrence in a person's lifetime. The major modalities of therapy are

Systemic antineoplastic modalities include

  • Hormonal therapy (for selected cancers, eg, prostate, breast, endometrium)

  • Immunotherapy including monoclonal antibodies, interferons, biologic response modifiers, tumor vaccines, and cell therapies (for many different types of cancer)

  • Differentiating drugs such as retinoids (for acute promyelocytic leukemia) and isocitrate dehydrogenase-2 (IDH2) inhibitors (for acute myeloid leukemia)

  • Targeted drugs that exploit the growing knowledge of genomics and cellular and molecular biology (eg, imatinib for chronic myeloid leukemia)

Often, modalities are combined to create a treatment program that is appropriate for the patient and based on patient and tumor characteristics as well as patient preferences. These modalities can be combined with the primary treatment at the same time or used before or after. The primary purpose of adjuvant therapy given after and neoadjuvant therapy given beforehand is to prevent cancer recurrence and increase survival.

Overall treatment should be coordinated among a radiation oncologist, surgeon, and medical oncologist, where appropriate. Choice of modalities constantly evolves, and numerous controlled research trials continue. When available and appropriate, clinical trial participation should be considered and discussed with patients.

Treatment decisions should weigh the likelihood of adverse effects against the likelihood of benefit; these decisions require frank communication and possibly the involvement of a multidisciplinary cancer team. Patient preferences for how to live out the end of life (see Advance Directives) should be established early in the course of cancer treatment despite the difficulties of discussing death at such a sensitive time.

Response to cancer treatment

Various terms are used to describe the response to treatment (see table Defining Response to Cancer Treatment). The disease-free or progression-free interval often serves as an indicator of cure and varies with cancer type. For example, lung, colon, bladder, large cell lymphomas, and testicular cancers are usually cured if a 5-yr disease-free interval occurs. However, breast and prostate cancers may recur long after 5 yr, an event defining tumor dormancy (now a major area of research); a 10-yr disease-free interval is more indicative of cure in these cancers.

Table
icon

Defining Response to Cancer Treatment

Term

Definition

Cure

Long-term absence of symptoms or signs of a disease, although patients who appear to be cured may still have cancer cells that could eventually cause relapse

Complete remission (complete response)

Disappearance of clinical evidence of disease

Partial response

> 50% reduction in size of a cancer mass or masses, sometimes leading to significant palliation and prolongation of life but with inevitable regrowth of the tumor

Stable disease

Neither improvement nor worsening

Disease-free survival (disease-free interval)

Interval between disappearance of the tumor and relapse

Progression-free interval

Time from initiation of treatment to time of progression

Survival time

Time from diagnosis to death

Survival rates with the different modalities, alone and in combination, are listed for selected cancers (see table Median 5-Yr Survival in Various Types of Cancer).

Table
icon

Median 5-Yr Survival in Various Types of Cancer

Type

Median 5-yr Survival (%)

Acute lymphocytic leukemia

68

Acute myeloid leukemia

26

Bladder

67

Bones and joints

67

Brain and other nervous system

33

Breast (female)

89

Cervix

68

Chronic lymphocytic leukemia

18

Chronic myeloid leukemia

63

Colon and rectum

69

Esophagus

18

Eye and orbit

82

Gallbladder

77

Hodgkin lymphoma

86

Kidney and renal pelvis

73

Larynx

61

Liver and intrahepatic bile duct

17

Lung and bronchus

17

Melanoma

92

Myeloma

47

Non-Hodgkin lymphoma

70

Oral cavity and pharynx

63

Ovary

46

Pancreas

7

Prostate

99

Soft tissue

65

Small intestine

66

Stomach

29

Testis

95

Thyroid

98

Uterus

82

Data from American Cancer Society: Cancer Treatment & Survivorship Facts & Figures 2016-2017. Atlanta, American Cancer Society; 2016.

Drugs Mentioned In This Article

Drug Name Select Trade
GLEEVEC
Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Professionals also read

Also of Interest

Videos

View All
Overview of Disseminated Intravascular Coagulation...
Video
Overview of Disseminated Intravascular Coagulation...
Overview of Acute Leukemia
Video
Overview of Acute Leukemia

SOCIAL MEDIA

TOP