Curing cancer requires eliminating all cells capable of causing cancer recurrence in a person's lifetime. The major modalities of therapy are
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Surgery (for local and local-regional disease)
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Radiation therapy (for local and local-regional disease)
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Systemic cancer therapy (for systemic disease)
Systemic cancer modalities include
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Hormonal therapy (for selected cancers, eg, prostate, breast, endometrium)
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Immune therapy including monoclonal antibodies, interferons, biologic response modifiers, tumor vaccines, and cell therapies (for many different types of cancer)
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Differentiating drugs such as retinoids (for acute promyelocytic leukemia) and isocitrate dehydrogenase-2 (IDH2) inhibitors (for acute myeloid leukemia)
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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, 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, which is given after, and neoadjuvant therapy, which is 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). Disease-free or progression-free survival 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 after 5 years of disease-free survival. However, breast and prostate cancers may recur long after 5 years, an event indicating tumor dormancy (now a major area of research); a 10-year disease-free interval is more indicative of cure in these cancers.
Defining Response to Cancer Treatment
Survival rates with the different modalities, alone and in combination, are listed for selected cancers (see table 5-Year Survival in Various Types of Cancer).
5-Year Survival in Various Types of Cancer
|
Type |
5-year Survival (%) |
|
Acute lymphocytic leukemia (children and adults) |
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 |
90 |
|
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. |
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