Cancer Treatment 101: A Primer for Non-Oncologists

Each year in the United States, approximately 1.7 million Americans are diagnosed with a potentially lethal malignancy. Typical therapies of choice include surgery, radiation, and occasionally, toxic chemotherapy (chemo) — approaches that eliminate the cancer in about 1,000,000 of these cases. The remaining 700,000 or so often proceed to chemotherapy either immediately or upon cancer recurrence, spread, or newly recognized metastases. “Cures” after that point are rare.
I’m speaking in generalities, understanding that each cancer and each patient is unique.
Chemotherapy alone can cure a small number of cancer types. When added to radiation or surgery, chemotherapy can help to cure a wider range of cancer types. As an add-on, chemotherapy can extend the length and quality of life for many patients with cancer. Since chemotherapy is by definition, “toxic,” it can also shorten the duration or harm the quality of life and provide false hope. The Table summarizes what chemotherapy can and cannot achieve in selected cancer types.
Careful, compassionate communication between patient and the physician is key. Goals and expectations must be clearly understood.
Organized chemotherapeutic efforts are further categorized as first line, second line, and third line.
First-line treatment. The initial round of recommended chemotherapy for a specific cancer. It is typically considered the most effective treatment for that type and stage of cancer on the basis of current research and clinical trials.
Second-line treatment. This is the treatment used if the first-line chemotherapy doesn’t work as desired. Reasons to switch to second-line chemo include:
Lack of response (the tumor failed to shrink);
Progression (the cancer may have grown or spread further); or
Adverse side effects were too severe to continue.
Third-line treatment. Third-line options come into play when both the initial course of chemo (first line) and the subsequent treatment (second line) have failed to achieve remission or control the cancer’s spread. Owing to the progressive nature of advanced cancers, patients might not be eligible or healthy enough for third-line therapy. Depending on cancer type, the patient’s general health, and response to previous treatments, third-line options could include:
New or different chemotherapy drugs compared with prior lines;
Surgery to debulk the tumor;
Radiation for symptom control;
Targeted therapy: drugs designed to target specific vulnerabilities in cancer cells;
Immunotherapy: agents that help the body’s immune system fight cancer cells; and
Clinical trials testing new or investigational treatments, which may be applicable at any time, depending on the questions being addressed.
It’s important to have realistic expectations about the potential outcomes of third-line therapy. Although remission may be unlikely, third-line therapy can still play a role in managing the disease.
Navigating advanced cancer treatment is very complex. The patient and physician must together consider detailed explanations and clarifications to set expectations and make informed decisions about care.
In traditional clinical oncology practice, other interventions are possible, but these may not be offered until treatment has reached the third line:
Molecular testing;
Palliation;
Clinical trials; or
Innovative testing to guide targeted therapy by ascertaining which agents are most likely (or not likely at all) to be effective.
Molecular testing. The best time for molecular testing of a new malignant tumor is typically at the time of diagnosis. Here’s why:
Molecular testing helps identify specific genetic mutations in the cancer cells. This information can be crucial for selecting targeted therapies that are most effective against those specific mutations. Early detection allows for the most treatment options. For example, for non–small cell lung cancer, early is best because treatment and outcomes may well be changed by test results.
Knowing the tumor’s molecular makeup can help determine whether a patient qualifies for clinical trials of new drugs designed for specific mutations.
Some molecular markers can offer information about the tumor’s aggressiveness and potential for metastasis so that prognosis can be informed.
Palliative care. The ideal time to discuss palliative care with a patient with cancer is early in the diagnosis and treatment process. Palliative care is not the same as hospice care; it isn’t just about end-of-life. Palliative care focuses on improving a patient’s quality of life throughout cancer treatment. Palliative care specialists can address a wide range of symptoms a patient might experience from cancer or its treatment, including pain, fatigue, nausea, and anxiety.
Early discussions allow for a more comprehensive care plan. Open communication about all treatment options, including palliative care, empowers patients to make informed decisions about their care goals and preferences.
Specific situations where discussing palliative care might be appropriate are:
Soon after a cancer diagnosis;
If the patient experiences significant side effects from cancer treatment;
When considering different treatment options, palliative care can complement those treatments; and
In advanced stages of cancer, to focus on comfort and quality of life.
In theory, clinical trials should be an option at any time in the patient’s course. But the organized clinical trial experience may not be available or appropriate. Then, the individual becomes a de facto “clinical trial with an n of 1.” Read this brief open-access blog post at Cancer Commons to learn more about that circumstance.
Innovative testing. The best choice of chemotherapeutic or targeted therapies is often unclear. The clinician is likely to follow published guidelines, often from the National Comprehensive Cancer Network.
These are evidence based and driven by consensus of experts. But guideline-recommended-therapy is not always effective, and weeks or months can pass before this ineffectiveness becomes apparent. Thus, many researchers and companies are seeking methods of testing each patient’s specific cancer to determine in advance, or very quickly, whether a particular drug is likely to be effective.
Read more about these leading innovations:
SAGE Oncotest: Entering the Next Generation of Tailored Cancer Treatment
Alibrex: A New Blood Test to Reveal Whether a Cancer Treatment is Working
PARIS Test Uses Lab-Grown Mini-Tumors to Find a Patient’s Best Treatment
Using Live Cells from Patients to Find the Right Cancer Drug
Treating Pancreatic Cancer: Could Metabolism—Not Genomics—Be the Key?
High-Energy Blue Light Powers a Promising New Treatment to Destroy Cancer Cells
All-Clear Follow-Up: Hydrogen Peroxide Appears to Treat Oral and Skin Lesions
Cancer is a tough nut to crack. Many people and organizations are trying very hard. So much is being learned. Some approaches will be effective. We can all hope.