Cancer develops when a gene is mutated, turning a normal cell into a fast-growing and multiplying cell. These cells will eventually develop into a tumour, an abnormal bundle of cells that grows faster and survives longer. A tumour can be benign or malignant. The difference between these two types is:
- Benign tumours: Usually grow at a slow rate without pushing on vital organs, and rarely spread through the body. Benign tumours can often be removed through surgery or treated with radiation or medication.
- Malignant tumour (cancer): Grows rapidly and may spread to other parts of the body (metastasis). Malignant tumours will push against the body's vital organs wherever they grow, causing strain and damage in the area.
There are many different types of cancers. Here are the most common cancers for people assigned male and female at birth:1
Most Commonly Diagnosed Cancer for People Assigned Male at Birth in 2020
Type of Cancer (% of total cancers)*: Lung (15.4)
Type of Cancer (% of total cancers)*: Prostate (15.1)
Type of Cancer (% of total cancers)*: Colorectal/Bowel (11.4)
Most Commonly Diagnosed Cancer for People Assigned Female at Birth in 2020
Type of Cancer (% of total cancers)**: Breast (25.8)
Type of Cancer (% of total cancers)**: Colorectal (9.9)
Type of Cancer (% of total cancers)**: Lung (8.8)
* based on a total of 9,342,957 patients diagnosed with cancer (non-melanoma)
** based on a total of 8,751,759 patients diagnosed with cancer (non-melanoma)
Cancer rate is rising globally and ranks second leading cause of death, taking the lives of 10 million each year.2 The UK ranked 13th with highest cancer rate in the world with 316,680 people diagnosed with cancer in 2018 – which is approximately 868 cancers diagnosed each day.3 Cancer is a public health priority in the 21st century, particularly in high-income countries such as the UK, South Korea, the US, and Germany.
Early diagnosis is the most important step because the stage at which a patient is diagnosed can dramatically determine how successful treatment can be. The different stages of cancer growth are normally described on a scale of 0-IV.
Beginning cancer treatment at stages I-II roughly gives patients an 80-99% survival rate, depending on the type of cancer. However, treatment at stages III-IV drastically reduces the chance of survival to approximately 5-20%.
In this article, we will discuss systemic cancer treatments: the different types, how they work, and which type of cancers would benefit most from them.
Systemic Cancer Treatment
What are systemic treatments?
The term “systemic” means a condition or disease is affecting the entire body. According to the National Cancer Institute, systemic treatment refers to the use of substances and drugs that travel through a person’s vascular system, affecting cells throughout the body.4
There are four common systemic cancer therapies: chemotherapy, hormonal treatment, targeted therapy and immunotherapy. Patients with cancer may be prescribed one or more systemic treatments depending on numerous factors, such as cancer type and stage.5
What does it mean when cancer is systemic?
There are two ways of seeing cancer as systemic: how it affects a person and how it develops. Cancer affects a patient systemically due to the cancer cells ability to cause a cascade of health problems. On the other hand, cancer as systemic can also mean it developed as an effect of a systemic combination of health problems.
How does systemic cancer treatment work?
The goal of systemic cancer treatment is to eliminate, control, and slow down the growth and spread of cancer cells. This often involves more than one type of treatment. Furthermore, they are prescribed to work alongside and improve other cancer treatments, such as surgical removal of tumour or radiation therapies.
The way systemic cancer treatments work is through the use of powerful drugs. Different systemic treatments may:
- Actively target cancer cells for destruction
- Block necessary materials cancer cells need to grow, such as hormones and blood vessels
- Boost the immune system’s functions to better target cancer cells.
Systemic Anticancer Treatment (SACT) is a collective term to describe the growing number of differing therapies used to treat cancers to achieve palliation, a relief of symptoms and suffering caused by cancer and other life-threatening diseases.6 The primary goal of systemic anticancer treatment is to improve symptoms and quality of life, not increase a patient’s life years.
Types of systemic cancer treatments
Chemotherapy is a drug treatment that utilises a controlled use of powerful chemicals to treat and eliminate both normal and cancerous cells that multiply faster than most other cells in your body.
Chemotherapy (often referred to as chemo) is often paired with other cancer treatments, such as:
- Neoadjuvant chemotherapy: uses chemo to first reduce the tumour size before surgery or radiation treatment.
- Adjuvant chemotherapy: uses chemo to eliminate any remaining cancer cells after surgery or radiation treatment.
- Chemo as a boost for other treatment options and treat cancer recurrence.
Healthy fast-growing cells, such as those that line the mouth, intestines, hair cells, and blood cells, can also be affected by chemotherapy. This is due to chemotherapy not being selective for tumour cells. The most common side effects of chemo are pain, fatigue, nausea, and emotional distress.
To cope with these side effects, a wide range of services and medications are available. Patients with cancer will be thoroughly consulted by a doctor before proceeding with this treatment.
Hormonal treatment is carried out through a drug that halts or interferes with the production of certain hormones needed for cancer cells to grow, and is often paired with other treatments.
Hormonal therapy can lower the risk of cancer recurrence. Patients with breast and prostate cancer often receive this treatment.
In the UK, 1 in 8 individuals assigned male at birth7 and 1 in 7 individuals assigned female at birth will be diagnosed with prostate or breast cancer, respectively, in their lifetime. Furthermore, 30% of those diagnosed with breast cancer will develop metastatic breast cancer, the leading cause of cancer death for those assigned female at birth.9
Metastatic breast cancer commonly spreads to nearby lymph nodes, bones, liver, lungs, and the brain. The survival rate is roughly 26% after stage IV diagnosis of metastatic breast cancer. At this stage, cancer treatment options will most likely be a combination of radiation therapy and chemotherapy with an aim to prolong life and reduce symptoms.
Targeted therapy is a precision medicine method that uses drug treatment to target specific cancer cell proteins that control how it grows, multiplies, and spreads.
Targeted therapy often uses artificially generated protein molecules called monoclonal antibodies that helps with cancer cell destruction. There are many ways in which targeted therapy helps fight cancer, such as by marking cancer cells for easier destruction by the immune system, delivering cytotoxins that cause cell destruction, and signalling for a halt or disruption of essential supplies, such as hormones and blood vessels, for cancer cell growth.
Immunotherapy is a drug treatment or biological therapy that boosts the immune system’s natural function to detect and destroy abnormal cells.
Cancer cells can often avoid detection through mutations, making it more difficult for the immune system to actively detect and destroy cancer cells. Immunotherapy primarily focuses on boosting the immune system's capability and is considered a targeted therapy as well.
Immunotherapy can remove inhibitors that prevent the immune system from responding too strongly to actively destroy cancer cells without limitations. It can also extract and enhance the most active T-cells, which are important to the immune system, and inject them back into the body.
Which type of cancers would benefit from systemic cancer treatment?
Systemic cancer treatment has notably improved the success rate in treating many types of cancers. Unlike the widely prescribed cancer treatments such as surgical removal of tumours and radiation therapies, the systemic cancer treatment has shown promising rates of improving the quality of life, reducing remission rates, and increasing the survival rate of cancer patients.
In the span of 30 to 40 years, systemic cancer treatment contributed to transforming the cancer treatment landscape. For example, Hodgkin’s Lymphoma was once universally fatal. However, with systemic cancer treatment options, 75-80% of patients are cured.10 Patients with other cancers, such as breast and prostate cancer, acute lymphoblastic leukaemia, testicular cancer, and colorectal cancer benefitted similarly through the systemic cancer treatment.
Systemic cancer treatment uses drug treatments to fight cancer through many treatment pathways, such as the direct destruction of cancer cells or boosting the body’s immune system. Systemic cancer treatment has dramatically improved the rate of successful cancer treatment.
While systemic treatments have shown to have a great benefit to cancer patients, there is more work to be done to make systemic cancer treatment more mainstream and to provide a more accessible and effective systemic cancer treatment.
- Worldwide cancer data [Internet]. WCRF International. 2022. Available from: https://www.wcrf.org/dietandcancer/worldwide-cancer-data/
- Roser M, Ritchie H. Cancer [Internet]. Our World in Data. 2015. Available from: https://ourworldindata.org/cancer#cancer-is-one-of-the-leading-causes-of-death
- Cancer registration statistics, England: first release, 2018 [Internet]. GOV.UK. 2020. Available from: https://www.gov.uk/government/statistics/cancer-registration-statistics-england-2018/cancer-registration-statistics-england-first-release-2018
- Systemic Therapy for Breast Cancer [Internet]. Memorial Sloan Kettering Cancer Centre. Available from: https://www.mskcc.org/cancer-care/types/breast/treatment/systemic-therapy
- Systemic treatments [Internet]. The Christie NHS Foundation Trust. 2019 [cited 24 June 2022]. Available from: https://www.christie.nhs.uk/patients-and-visitors/services/clinical-oncology/systemic-treatments
- Usborne CM, Mullard AP. A review of systemic anticancer therapy in disease palliation. British Medical Bulletin. 2017 Nov 28;125(1):43–53.
- About Prostate Cancer [Internet]. Prostate Cancer UK. [cited 24 June 2022]. Available from: https://prostatecanceruk.org/prostate-information/about-prostate-cancer
- Statistics by cancer type [Internet]. Cancer Research UK. [cited 24 June 2022]. Available from: https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/
- Redig A, McAllister S. Breast cancer as a systemic disease: a view of metastasis. Journal of Internal Medicine. 2013;274(2):113-126.
- Palumbo M, Kavan P, Miller W, Panasci L, Assouline S, Johnson N et al. Systemic cancer therapy: achievements and challenges that lie ahead. Frontiers in Pharmacology. 2013;4.