Top five list of things to consider in cancer treatment

The “Top 5” list prepared by the American Society of Clinical Oncology (ASCO) to prevent the frequent or inappropriate use of medical tests and/or methods that do not benefit cancer patients and may even be harmful, and to improve the quality of cancer treatment, has been published in the Journal of Medical Oncology.

Cancer is a disease for which sometimes aggressive and sometimes non-aggressive treatment methods are applied for various reasons. The treatment methods used may cause some side effects in patients’ general condition and, from time to time, serious consequences. In this regard, all necessary examinations should be performed when planning treatment, and the patient’s age, any other health problems, and the stage and extent of spread of the diagnosed cancer should be taken into consideration. Otherwise, various adverse outcomes may cause difficulties for both the patient and the physician. A correct treatment plan can improve the quality of life by preventing certain problems that cancer patients may experience. For this reason, in order to raise awareness among both patients and the oncology community, the aim has been to reduce as much as possible the inappropriate use of tests and/or methods not supported by clinical research. The “Top 5” list, created for the second time by the American Society of Clinical Oncology (ASCO) as part of the “Choosing Wisely” campaign initiated by the American Board of Internal Medicine, has been published in the Journal of Medical Oncology. This list aims to improve the quality of cancer treatment by preventing the frequent or inappropriate use of medical tests and/or methods that provide little benefit to cancer patients and may even be harmful.

The Top 5 list prepared by ASCO has been presented to the public to identify tests, treatments, or drugs that are frequently used but provide little benefit in cancer care, to make recommendations, and to raise public awareness. Each recommendation on this list, developed by ASCO’s “Cancer Treatment Evaluation Team,” is based on a comprehensive summary of current medical evidence.

1. When patients are given chemotherapy regimens that carry little risk of nausea or vomiting, antiemetic (vomiting-preventing) drugs used for regimens with a high risk of vomiting and nausea should not be recommended.
   Nausea and vomiting are among the most common side effects of chemotherapy treatment. In systemic chemotherapy treatment, there are some agents that reduce the risk of chemotherapy-related nausea and vomiting. In addition, some chemotherapy drugs cause much more nausea and vomiting than others; these are called emetogenic chemotherapy drugs. ASCO has revised the emetogenic classification of chemotherapy drugs and determined in which treatments stronger antiemetic (nausea- and vomiting-preventing) drugs should be used.
   Antiemetic drugs are used to reduce nausea and vomiting and to improve cancer patients’ quality of life while they are receiving chemotherapy. However, not every patient may need these drugs. These drugs, which may impose an economic burden on cancer patients, have their own side effects. For these reasons, ASCO recommends that such drugs, which may cause serious and persistent side effects, be used together with chemotherapy when deemed necessary. Thus, the patient will not experience additional physical discomfort, and the drugs will not constitute an economic burden.
2. Unless the patient has severe symptoms and these symptoms need to be alleviated, combination chemotherapy (multiple drugs) should not be administered instead of single-agent chemotherapy in patients with metastatic breast cancer.
   Although a chemotherapy combination consisting of multiple drugs may benefit the cancer patient, it can cause serious side effects and negatively affect the patient’s quality of life. In addition, treatments administered one drug at a time reduce the risk of possible side effects, improve the patient’s quality of life, and ensure maximum benefit from each drug.
   Cytotoxic chemotherapy treatment administered for aggressive or recurrent breast cancer that poses a vital risk is one of the methods with which oncologists often achieve success. After chemotherapy, the disease is generally observed to regress in patients with breast cancer. Chemotherapy combined with palliative treatment used to eliminate or reduce symptoms may extend survival before the cancer progresses. However, with the methods used today, metastatic breast cancer is among the diseases that cannot be cured. Therefore, in the treatment of women with metastatic breast cancer, the positive and negative outcomes obtained and treatment-related side effects should be balanced.
   In patients with advanced-stage or metastatic cancer, a combination of two or more cytotoxic drugs may slow tumor growth and delay disease progression more than single-agent treatment, but it increases toxicity (biological harm caused by a chemical or physical factor). It has been observed that combination treatment, which can cause serious side effects and has been found not to prolong survival, provides no benefit to the patient.
   For this reason, ASCO recommends that, unless necessary, combination chemotherapy—which has no effect on overall survival in patients with metastatic breast cancer and causes side effects—not be administered; instead, a single-agent regimen that improves the patient’s quality of life should be preferred.
3. Advanced imaging technologies such as positron emission tomography (PET), CT, and radionuclide bone scans used to image cancer recurrence should not be performed in patients who have completed first-line treatment and subsequently show no signs of cancer unless necessary. Positron emission tomography (PET) and PET-CT (computed tomography) are methods used to diagnose cancer, visualize the stage of cancer and the course of treatment, and develop the best treatment plan. These tests, which are used to image cancer recurrence, are not recommended for this purpose because they do not affect the course or outcome of the disease. False-positive tests may lead to the use of unnecessary and aggressive procedures in the patient, treatment beyond what is necessary, and additional radiation exposure. Therefore, these screening tests should not be used unless there is strong evidence that routine PET or PET-CT imaging techniques benefit the patient.
   In recent years, the potential for unnecessary PET-CT use has been observed in patients who show no signs of disease and undergo observation after completing treatment. For this reason, the latest decision made by the National Oncology PET Department is that PET and CT are not appropriate screening tests for routine observation, except for cancer staging and subsequent follow-up.
   The evidence obtained has shown that PET or PET-CT examinations used to image cancer recurrence in patients who have completed first-line cancer treatment and show no signs of disease do not provide a positive contribution to survival or disease outcome. These methods may produce false-positive results that unnecessarily expose the patient to additional treatment or additional radiation.
4. The prostate-specific antigen (PSA) test used to identify prostate cancer should not be performed in men who are thought to have less than 10 years to live because of various health problems and who show no signs of disease.
   Many doctors frequently recommend PSA testing to men who show no signs of disease, believing that the level of prostate-specific antigen (PSA) in the blood is associated with prostate cancer, in the hope of diagnosing prostate cancer early. Unfortunately, however, the PSA test is not as useful as many people hope. Many men with prostate cancer do not have elevated PSA levels. In addition, PSA levels may increase because of health problems other than cancer, such as benign prostatic hyperplasia. Furthermore, the fact that PSA testing is not very effective in the early diagnosis of prostate cancer may be cited as one reason why no evidence has been found that it prolongs survival.
   PSA is a protein associated with benign or malignant prostatic disorders and is generally associated with the presence of abnormalities occurring in the prostate. PSA is also produced by malignant prostate tissues and is mostly associated with tumor development and disease progression.
   Despite all this, PSA levels have played a decisive role in the early diagnosis and treatment of prostate cancer to date. In fact, PSA testing is the primary reason screening tests play an important role in the early diagnosis of many types of cancer. However, prostate cancer is a heterogeneous disease, and its subtypes may exist for years without threatening life in older men. Although some research findings have determined that screening tests contribute to overall survival, the evidence indicates that PSA testing does not benefit men who show no signs of disease and may even be harmful in older men.
   In conclusion, the prostate-specific antigen (PSA) test performed in men expected to live less than 10 years because of chronic diseases or certain health problems has been found to provide no benefit. This test may sometimes lead to unnecessary biopsy or treatment for the patient.
5. Targeted therapy should not be administered solely because of genetic abnormalities without identifying tumor cells with specific biomarkers that respond to the targeted treatment.
   Unlike chemotherapy, targeted therapy can benefit patients with cancer because it can target the gene products that cause cancer (proteins that promote the development and spread of cancer cells, etc.). The tumor cells of patients who benefit most from targeted therapy contain certain biomarkers that indicate specific genetic changes and are sensitive to the targeted drug. Targeted therapy is more expensive than chemotherapy because it is newer, more costly to produce, and protected by patents. As with all cancer treatments, administering targeted therapy without any evidence to support its use in the patient may entail certain risks. The patient may experience serious side effects, or the treatment may not be more effective compared with other treatment options.
   For this reason, targeted therapy most often benefits patients in whom tumor cells with specific biomarkers have been identified and should be administered only to cancer patients with a treatment plan directed at an identified target.

Advances in cancer treatment have now reached a point at which they can show what type of treatment is likely to benefit the patient most and what type of approach may be harmful. Indeed, potentially effective treatment methods can be identified in advance and a plan can be developed accordingly. In this way, problems the patient may encounter during and after cancer treatment can often be avoided. These encouraging and hopeful advances will continue to guide us oncologists and help our patients get through this difficult process more easily.